[RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

 Hi all, 
   
 I want to hear your opinions about this proposal for consistency of
 mount directory to mount debugfs filesystem that need  by ftrace infrastructure.
 Um... I appended "RFC" word in the subject because this mail is my proposal just.  


commit 1766a83645706100b1829bb422f852ec757c6f4b
Author: GeunSik,Lim <leemgs1@gmail.com>
Date:   Tue May 26 13:49:23 2009 +0900

    Fix terminology inconsistency of dir name to mount debugfs filesystem.
    
      Many developers use "/debug/" directory name to mount debugfs filesystem
      for ftrace according to ./Documentation/tracers/ftrace.txt file.
    
      But, two directory names(ex:/debug/, /debugfs/) is existed in kernel source
      like ftrace, DRM, Wireless, Network[sky2]files to mount debugfs filesystem.
      I think that we don't have to select either "/debug/" directory name or
      "/debugfs/" directory name for terminology consistency.
    
      debugfs means debug filesystem for debugging easy to use by greg kroah
      hartman. "/debug/" name is suitable as directory name of debugfs for
      tracing using ftrace like "/sys/" of sysfs(system filesystem).
      -debugfs related reference: http://lwn.net/Articles/115405/
    
      Fix inconsistency of directory name according to duplicated expression
      to mount debugfs.
    
         Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
---
 Documentation/DocBook/debugobjects.tmpl |    2 +-
 drivers/block/pktcdvd.c                 |    2 +-
 drivers/gpu/drm/drm_debugfs.c           |   12 ++++++------
 drivers/gpu/drm/drm_drv.c               |    2 +-
 drivers/gpu/drm/drm_stub.c              |    2 +-
 drivers/net/Kconfig                     |    4 ++--
 drivers/net/wimax/i2400m/i2400m.h       |    2 +-
 drivers/net/wireless/libertas/README    |   12 ++++++------
 include/linux/kernel.h                  |    2 +-
 kernel/trace/Kconfig                    |   10 +++++-----
 kernel/trace/trace.c                    |    2 +-
 11 files changed, 26 insertions(+), 26 deletions(-)


diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl
index 7f5f218..9beb77a 100644
--- a/Documentation/DocBook/debugobjects.tmpl
+++ b/Documentation/DocBook/debugobjects.tmpl
@@ -106,7 +106,7 @@
       number of errors are printk'ed including a full stack trace.
     </para>
     <para>
-      The statistics are available via debugfs/debug_objects/stats.
+      The statistics are available via /debug/debug_objects/stats.
       They provide information about the number of warnings and the
       number of successful fixups along with information about the
       usage of the internal tracking objects and the state of the
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index dc7a8c3..36989b0 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -430,7 +430,7 @@ static void pkt_sysfs_cleanup(void)
 /********************************************************************
   entries in debugfs
 
-  /debugfs/pktcdvd[0-7]/
+  /debug/pktcdvd[0-7]/
 			info
 
  *******************************************************************/
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index c77c6c6..04a2ccf 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -105,7 +105,7 @@ int drm_debugfs_create_files(struct drm_info_list *files, int count,
 		ent = debugfs_create_file(files[i].name, S_IFREG | S_IRUGO,
 					  root, tmp, &drm_debugfs_fops);
 		if (!ent) {
-			DRM_ERROR("Cannot create /debugfs/dri/%s/%s\n",
+			DRM_ERROR("Cannot create /debug/dri/%s/%s\n",
 				  name, files[i].name);
 			drm_free(tmp, sizeof(struct drm_info_node),
 				 _DRM_DRIVER);
@@ -133,9 +133,9 @@ EXPORT_SYMBOL(drm_debugfs_create_files);
  * \param minor device minor number
  * \param root DRI debugfs dir entry.
  *
- * Create the DRI debugfs root entry "/debugfs/dri", the device debugfs root entry
- * "/debugfs/dri/%minor%/", and each entry in debugfs_list as
- * "/debugfs/dri/%minor%/%name%".
+ * Create the DRI debugfs root entry "/debug/dri", the device debugfs root entry
+ * "/debug/dri/%minor%/", and each entry in debugfs_list as
+ * "/debug/dri/%minor%/%name%".
  */
 int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		     struct dentry *root)
@@ -148,7 +148,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 	sprintf(name, "%d", minor_id);
 	minor->debugfs_root = debugfs_create_dir(name, root);
 	if (!minor->debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri/%s\n", name);
+		DRM_ERROR("Cannot create /debug/dri/%s\n", name);
 		return -1;
 	}
 
@@ -165,7 +165,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		ret = dev->driver->debugfs_init(minor);
 		if (ret) {
 			DRM_ERROR("DRM: Driver failed to initialize "
-				  "/debugfs/dri.\n");
+				  "/debug/dri.\n");
 			return ret;
 		}
 	}
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 019b7c5..5472e67 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -339,7 +339,7 @@ static int __init drm_core_init(void)
 
 	drm_debugfs_root = debugfs_create_dir("dri", NULL);
 	if (!drm_debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri\n");
+		DRM_ERROR("Cannot create /debug/dri\n");
 		ret = -1;
 		goto err_p3;
 	}
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index b9631e3..9488769 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -328,7 +328,7 @@ static int drm_get_minor(struct drm_device *dev, struct drm_minor **minor, int t
 #if defined(CONFIG_DEBUG_FS)
 	ret = drm_debugfs_init(new_minor, minor_id, drm_debugfs_root);
 	if (ret) {
-		DRM_ERROR("DRM: Failed to initialize /debugfs/dri.\n");
+		DRM_ERROR("DRM: Failed to initialize /debug/dri.\n");
 		goto err_g2;
 	}
 #endif
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 214a92d..898c269 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2200,7 +2200,7 @@ config SKGE_DEBUG
        depends on SKGE && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/skge/ethX displays the state of the internal
+	 The file /debug/skge/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
@@ -2226,7 +2226,7 @@ config SKY2_DEBUG
        depends on SKY2 && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/sky2/ethX displays the state of the internal
+	 The file /debug/sky2/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
diff --git a/drivers/net/wimax/i2400m/i2400m.h b/drivers/net/wimax/i2400m/i2400m.h
index 3ae2df3..2366696 100644
--- a/drivers/net/wimax/i2400m/i2400m.h
+++ b/drivers/net/wimax/i2400m/i2400m.h
@@ -389,7 +389,7 @@ struct i2400m {
 	unsigned ready:1;		/* all probing steps done */
 	unsigned rx_reorder:1;		/* RX reorder is enabled */
 	u8 trace_msg_from_user;		/* echo rx msgs to 'trace' pipe */
-					/* typed u8 so debugfs/u8 can tweak */
+					/* typed u8 so /debug/u8 can tweak */
 	enum i2400m_system_state state;
 	wait_queue_head_t state_wq;	/* Woken up when on state updates */
 
diff --git a/drivers/net/wireless/libertas/README b/drivers/net/wireless/libertas/README
index d860fc3..11616ba 100644
--- a/drivers/net/wireless/libertas/README
+++ b/drivers/net/wireless/libertas/README
@@ -72,7 +72,7 @@ rdrf
 	location that is to be read.  This parameter must be specified in
 	hexadecimal (its possible to preceed preceding the number with a "0x").
 
-	Path: /debugfs/libertas_wireless/ethX/registers/
+	Path: /debug/libertas_wireless/ethX/registers/
 
 	Usage:
 		echo "0xa123" > rdmac ; cat rdmac
@@ -95,7 +95,7 @@ wrrf
 sleepparams
 	This command is used to set the sleepclock configurations
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /debug/libertas_wireless/ethX/
 
 	Usage:
 		cat sleepparams: reads the current sleepclock configuration
@@ -115,7 +115,7 @@ subscribed_events
 	The subscribed_events directory contains the interface for the
 	subscribed events API.
 
-	Path: /debugfs/libertas_wireless/ethX/subscribed_events/
+	Path: /debug/libertas_wireless/ethX/subscribed_events/
 
 	Each event is represented by a filename. Each filename consists of the
 	following three fields:
@@ -165,7 +165,7 @@ subscribed_events
 extscan
 	This command is used to do a specific scan.
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /debug/libertas_wireless/ethX/
 
 	Usage: echo "SSID" > extscan
 
@@ -179,7 +179,7 @@ getscantable
 	Display the current contents of the driver scan table (ie. get the
 	scan results).
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /debug/libertas_wireless/ethX/
 
 	Usage:
 		cat getscantable
@@ -188,7 +188,7 @@ setuserscan
 	Initiate a customized scan and retrieve the results
 
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /debug/libertas_wireless/ethX/
 
     Usage:
        echo "[ARGS]" > setuserscan
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 883cd44..7ffa753 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -406,7 +406,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
  *
  * Use tracing_on/tracing_off when you want to quickly turn on or off
  * tracing. It simply enables or disables the recording of the trace events.
- * This also corresponds to the user space debugfs/tracing/tracing_on
+ * This also corresponds to the user space /debug/tracing/tracing_on
  * file, which gives a means for the kernel and userspace to interact.
  * Place a tracing_off() in the kernel where you want tracing to end.
  * From user space, examine the trace, and then echo 1 > tracing_on
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 417d198..7fcc3d6 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -120,7 +120,7 @@ config IRQSOFF_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the preempt-off timing option can be
@@ -141,7 +141,7 @@ config PREEMPT_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the irqs-off timing option can be
@@ -213,7 +213,7 @@ config TRACE_BRANCH_PROFILING
 	  This tracer profiles all the the likely and unlikely macros
 	  in the kernel. It will display the results in:
 
-	  /debugfs/tracing/profile_annotated_branch
+	  /debug/tracing/profile_annotated_branch
 
 	  Note: this will add a significant overhead, only turn this
 	  on if you need to profile the system's use of these macros.
@@ -228,7 +228,7 @@ config PROFILE_ALL_BRANCHES
 	  taken in the kernel is recorded whether it hit or miss.
 	  The results will be displayed in:
 
-	  /debugfs/tracing/profile_branch
+	  /debug/tracing/profile_branch
 
 	  This configuration, when enabled, will impose a great overhead
 	  on the system. This should only be enabled when the system
@@ -276,7 +276,7 @@ config STACK_TRACER
 	select KALLSYMS
 	help
 	  This special tracer records the maximum stack footprint of the
-	  kernel and displays it in debugfs/tracing/stack_trace.
+	  kernel and displays it in /debug/tracing/stack_trace.
 
 	  This tracer works by hooking into every function call that the
 	  kernel executes, and keeping a maximum stack depth value and
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index cda81ec..b474e8c 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -335,7 +335,7 @@ static raw_spinlock_t ftrace_max_lock =
 /*
  * Copy the new maximum trace into the separate maximum-trace
  * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /debugfs/tracing/latency_trace)
+ * for later retrieval via /debug/tracing/latency_trace)
  */
 static void
 __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)


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GeunSik Lim (ELS - OS Group - S/W Lab - SAIT - SAMSUNG)
e-Mail  :1) geunsik.lim@samsung.com
         2) leemgs@gmail.com , leemgs1@gmail.com
HomePage: http://intomail.dnip.net/invain/me/
-----------------------------------------------

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Iñaky Pérez-González]

On Monday 25 May 2009, GeunSik Lim wrote:
>  Hi all,
>
>  I want to hear your opinions about this proposal for consistency of
>  mount directory to mount debugfs filesystem that need  by ftrace
> infrastructure. Um... I appended "RFC" word in the subject because this
> mail is my proposal just.
>
>
> commit 1766a83645706100b1829bb422f852ec757c6f4b
> Author: GeunSik,Lim <leemgs1@gmail.com>
> Date:   Tue May 26 13:49:23 2009 +0900
>
>     Fix terminology inconsistency of dir name to mount debugfs filesystem.
>
>       Many developers use "/debug/" directory name to mount debugfs
> filesystem for ftrace according to ./Documentation/tracers/ftrace.txt file.
>
>       But, two directory names(ex:/debug/, /debugfs/) is existed in kernel
> source like ftrace, DRM, Wireless, Network[sky2]files to mount debugfs
> filesystem. I think that we don't have to select either "/debug/" directory
> name or "/debugfs/" directory name for terminology consistency.
>
>       debugfs means debug filesystem for debugging easy to use by greg
> kroah hartman. "/debug/" name is suitable as directory name of debugfs for
> tracing using ftrace like "/sys/" of sysfs(system filesystem). -debugfs
> related reference: http://lwn.net/Articles/115405/
>
>       Fix inconsistency of directory name according to duplicated
> expression to mount debugfs.
>
>          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>

For the WiMAX part, not really an issue:

Acked-By: Inaky Perez-Gonzalez <inaky@linux.intel.com>

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Tue, 26 May 2009, GeunSik Lim wrote:

> 
> 
>  Hi all, 
>    
>  I want to hear your opinions about this proposal for consistency of
>  mount directory to mount debugfs filesystem that need  by ftrace infrastructure.
>  Um... I appended "RFC" word in the subject because this mail is my proposal just.  
> 
> 
> commit 1766a83645706100b1829bb422f852ec757c6f4b
> Author: GeunSik,Lim <leemgs1@gmail.com>
> Date:   Tue May 26 13:49:23 2009 +0900
> 
>     Fix terminology inconsistency of dir name to mount debugfs filesystem.
>     
>       Many developers use "/debug/" directory name to mount debugfs filesystem
>       for ftrace according to ./Documentation/tracers/ftrace.txt file.
>     
>       But, two directory names(ex:/debug/, /debugfs/) is existed in kernel source
>       like ftrace, DRM, Wireless, Network[sky2]files to mount debugfs filesystem.
>       I think that we don't have to select either "/debug/" directory name or
>       "/debugfs/" directory name for terminology consistency.
>     
>       debugfs means debug filesystem for debugging easy to use by greg kroah
>       hartman. "/debug/" name is suitable as directory name of debugfs for
>       tracing using ftrace like "/sys/" of sysfs(system filesystem).
>       -debugfs related reference: http://lwn.net/Articles/115405/
>     
>       Fix inconsistency of directory name according to duplicated expression
>       to mount debugfs.
>     
>          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>

I'm guilty of using both /debug and /debugfs in comments. In practice, I 
only use /debug.

But...

The filesystem Nazi's out there will argue that the proper place to mount 
the debugfs filesystem is /sys/kernel/debug. I personally find that 
location annoying.

-- Steve

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Greg KH]

On Tue, May 26, 2009 at 04:44:49PM -0400, Steven Rostedt wrote:
> 
> On Tue, 26 May 2009, GeunSik Lim wrote:
> 
> > 
> > 
> >  Hi all, 
> >    
> >  I want to hear your opinions about this proposal for consistency of
> >  mount directory to mount debugfs filesystem that need  by ftrace infrastructure.
> >  Um... I appended "RFC" word in the subject because this mail is my proposal just.  
> > 
> > 
> > commit 1766a83645706100b1829bb422f852ec757c6f4b
> > Author: GeunSik,Lim <leemgs1@gmail.com>
> > Date:   Tue May 26 13:49:23 2009 +0900
> > 
> >     Fix terminology inconsistency of dir name to mount debugfs filesystem.
> >     
> >       Many developers use "/debug/" directory name to mount debugfs filesystem
> >       for ftrace according to ./Documentation/tracers/ftrace.txt file.
> >     
> >       But, two directory names(ex:/debug/, /debugfs/) is existed in kernel source
> >       like ftrace, DRM, Wireless, Network[sky2]files to mount debugfs filesystem.
> >       I think that we don't have to select either "/debug/" directory name or
> >       "/debugfs/" directory name for terminology consistency.
> >     
> >       debugfs means debug filesystem for debugging easy to use by greg kroah
> >       hartman. "/debug/" name is suitable as directory name of debugfs for
> >       tracing using ftrace like "/sys/" of sysfs(system filesystem).
> >       -debugfs related reference: http://lwn.net/Articles/115405/
> >     
> >       Fix inconsistency of directory name according to duplicated expression
> >       to mount debugfs.
> >     
> >          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
> 
> I'm guilty of using both /debug and /debugfs in comments. In practice, I 
> only use /debug.
> 
> But...
> 
> The filesystem Nazi's out there will argue that the proper place to mount 
> the debugfs filesystem is /sys/kernel/debug. I personally find that 
> location annoying.

Why?

When I created debugfs, I was told that I had to pick a place to mount
it so that everyone could write scripts that "knew" where it would be.

So we picked /sys/kernel/debug/ and the code creates the mount point to
put it there.  Now distros actually mount debugfs at that location.

So, now you don't like this?  After it's become a standard?  Ick.

Becides, /debug/ is pretty presumptious, it's as if debugging the kernel
is a system-wide thing :)

So please, don't use /debug/ use the standard, defined, and ACTUALLY
USED BY DISTROS TODAY mount point of /sys/kernel/debug/

If you want to create your own symlink from /debug/ to that location to
make it easier to type, feel free, but do not hard code any scripts to
use that location, or they are going to break.

thanks,

greg k-h

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Tue, 26 May 2009, Greg KH wrote:
> > 
> > The filesystem Nazi's out there will argue that the proper place to mount 
> > the debugfs filesystem is /sys/kernel/debug. I personally find that 
> > location annoying.
> 
> Why?

Because it is too much to type ;-)

> 
> When I created debugfs, I was told that I had to pick a place to mount
> it so that everyone could write scripts that "knew" where it would be.
> 
> So we picked /sys/kernel/debug/ and the code creates the mount point to
> put it there.  Now distros actually mount debugfs at that location.
> 
> So, now you don't like this?  After it's become a standard?  Ick.
> 
> Becides, /debug/ is pretty presumptious, it's as if debugging the kernel
> is a system-wide thing :)
> 
> So please, don't use /debug/ use the standard, defined, and ACTUALLY
> USED BY DISTROS TODAY mount point of /sys/kernel/debug/
> 
> If you want to create your own symlink from /debug/ to that location to
> make it easier to type, feel free, but do not hard code any scripts to
> use that location, or they are going to break.

All my scripts search /proc/mounts to find where debugfs is mounted, then 
it uses that.

Hmm, Not sure what packages in the distros use the default. I don't see 
the debugfs in /etc/fstab in any of my machines.

-- Steve

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Greg KH]

On Tue, May 26, 2009 at 05:15:09PM -0400, Steven Rostedt wrote:
> All my scripts search /proc/mounts to find where debugfs is mounted, then 
> it uses that.

Good.

> Hmm, Not sure what packages in the distros use the default. I don't see 
> the debugfs in /etc/fstab in any of my machines.

It's in mine, I don't know what packages use it at the moment.

thanks,

greg k-h

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

On Wed, May 27, 2009 at 6:15 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Tue, 26 May 2009, Greg KH wrote:
>> >
>> > The filesystem Nazi's out there will argue that the proper place to mount
>> > the debugfs filesystem is /sys/kernel/debug. I personally find that
>> > location annoying.
>>
>> Why?
>
> Because it is too much to type ;-)
I think so. But, when we consider many developers that use linux kernel
source all over the world, I think that a regular rules or consistency
is important
as greg k-h explained.

Recently, I read "ftrace-world.odp" presentation file  of steven rostedt.

For example, about Mounting debugfs...
#> mount -t debugfs nodev /sys/kernel/debug
OR
#> mkdir /debug
#> mount -t debugfs nodev /debug

I want that we will reach a consensus about mount directory name of
debugfs filesystem to avoid confusing among the kernel developers.

/debug/ ?
or   /sys/kernel/debug/?
 .....

Frankly speaking, I like /sys/kernel/debug/ rule is better than /debug/ rule
for consistency.

>
>>
>> When I created debugfs, I was told that I had to pick a place to mount
>> it so that everyone could write scripts that "knew" where it would be.
>>
>> So we picked /sys/kernel/debug/ and the code creates the mount point to
>> put it there.  Now distros actually mount debugfs at that location.
>>
>> So, now you don't like this?  After it's become a standard?  Ick.
>>
>> Becides, /debug/ is pretty presumptious, it's as if debugging the kernel
>> is a system-wide thing :)
>>
>> So please, don't use /debug/ use the standard, defined, and ACTUALLY
>> USED BY DISTROS TODAY mount point of /sys/kernel/debug/
>>
>> If you want to create your own symlink from /debug/ to that location to
>> make it easier to type, feel free, but do not hard code any scripts to
>> use that location, or they are going to break.
>
> All my scripts search /proc/mounts to find where debugfs is mounted, then
> it uses that.
>
> Hmm, Not sure what packages in the distros use the default. I don't see
> the debugfs in /etc/fstab in any of my machines.
>
Yes.. In my case, I use linux distributions like Ubuntu 8.10, Fedora
9/10, CENTOS 5.3 currently. This distributions  use proc , tmpfs,
devpts, sysfs for official release
by default.

> -- Steve
>
>



-- 
Regards,
GeunSik Lim
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Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

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On Wed, 27 May 2009, GeunSik Lim wrote:

> On Wed, May 27, 2009 at 6:15 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > On Tue, 26 May 2009, Greg KH wrote:
> >> >
> >> > The filesystem Nazi's out there will argue that the proper place to mount
> >> > the debugfs filesystem is /sys/kernel/debug. I personally find that
> >> > location annoying.
> >>
> >> Why?
> >
> > Because it is too much to type ;-)
> I think so. But, when we consider many developers that use linux kernel
> source all over the world, I think that a regular rules or consistency
> is important
> as greg k-h explained.
> 
> Recently, I read "ftrace-world.odp" presentation file  of steven rostedt.
> 
> For example, about Mounting debugfs...
> #> mount -t debugfs nodev /sys/kernel/debug
> OR
> #> mkdir /debug
> #> mount -t debugfs nodev /debug
> 
> I want that we will reach a consensus about mount directory name of
> debugfs filesystem to avoid confusing among the kernel developers.
> 
> /debug/ ?
> or   /sys/kernel/debug/?
>  .....
> 
> Frankly speaking, I like /sys/kernel/debug/ rule is better than /debug/ rule
> for consistency.

And this is why I always mention that directory.

> 
> >
> >>
> >> When I created debugfs, I was told that I had to pick a place to mount
> >> it so that everyone could write scripts that "knew" where it would be.
> >>
> >> So we picked /sys/kernel/debug/ and the code creates the mount point to
> >> put it there.  Now distros actually mount debugfs at that location.
> >>
> >> So, now you don't like this?  After it's become a standard?  Ick.
> >>
> >> Becides, /debug/ is pretty presumptious, it's as if debugging the kernel
> >> is a system-wide thing :)
> >>
> >> So please, don't use /debug/ use the standard, defined, and ACTUALLY
> >> USED BY DISTROS TODAY mount point of /sys/kernel/debug/
> >>
> >> If you want to create your own symlink from /debug/ to that location to
> >> make it easier to type, feel free, but do not hard code any scripts to
> >> use that location, or they are going to break.
> >
> > All my scripts search /proc/mounts to find where debugfs is mounted, then
> > it uses that.
> >
> > Hmm, Not sure what packages in the distros use the default. I don't see
> > the debugfs in /etc/fstab in any of my machines.
> >
> Yes.. In my case, I use linux distributions like Ubuntu 8.10, Fedora
> 9/10, CENTOS 5.3 currently. This distributions  use proc , tmpfs,
> devpts, sysfs for official release
> by default.
> 

The key thing is not to have scripts depend on a path. When debugfs is 
enabled in a kernel, you automatically get /sys/kernel/debug, so that is a 
natural place to mount it.

I have also suggested to people (as Greg suggested earlier to me) that you 
can mount it there and then make a soft link to it. Which also works.

I personally just mount it at /debug.

To handle the scripts problem, all my scripts start with:

# grep debugfs /proc/mounts | cut -d ' ' -f 2

I also have a C function to do a search for debugfs in /proc/mounts.

If you look in Documentation/trace/ftrace.txt I have:

===
To mount the debugfs system:

  # mkdir /debug
  # mount -t debugfs nodev /debug

( Note: it is more common to mount at /sys/kernel/debug, but for
  simplicity this document will use /debug)
===

Thus it is a personal preference of mine to put it at /debug. But I do not 
hide the fact that it is recommended to be in /sys/kernel/debug. Heck, I'm 
the one that brought to light that path in this thread. I just curse it 
everytime I have to say it ;-)

-- Steve

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

On Wed, May 27, 2009 at 11:38 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
>
>
>
> On Wed, 27 May 2009, GeunSik Lim wrote:
>
>> On Wed, May 27, 2009 at 6:15 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
>> >
>> > On Tue, 26 May 2009, Greg KH wrote:
>> >> >
>> >> > The filesystem Nazi's out there will argue that the proper place to mount
>> >> > the debugfs filesystem is /sys/kernel/debug. I personally find that
>> >> > location annoying.
>> >>
>> >> Why?
>> >
>> > Because it is too much to type ;-)
>> I think so. But, when we consider many developers that use linux kernel
>> source all over the world, I think that a regular rules or consistency
>> is important
>> as greg k-h explained.
>>
>> Recently, I read "ftrace-world.odp" presentation file  of steven rostedt.
>>
>> For example, about Mounting debugfs...
>> #> mount -t debugfs nodev /sys/kernel/debug
>> OR
>> #> mkdir /debug
>> #> mount -t debugfs nodev /debug
>>
>> I want that we will reach a consensus about mount directory name of
>> debugfs filesystem to avoid confusing among the kernel developers.
>>
>> /debug/ ?
>> or   /sys/kernel/debug/?
>>  .....
>>
>> Frankly speaking, I like /sys/kernel/debug/ rule is better than /debug/ rule
>> for consistency.
>
> And this is why I always mention that directory.
>
>>
>> >
>> >>
>> >> When I created debugfs, I was told that I had to pick a place to mount
>> >> it so that everyone could write scripts that "knew" where it would be.
>> >>
>> >> So we picked /sys/kernel/debug/ and the code creates the mount point to
>> >> put it there.  Now distros actually mount debugfs at that location.
>> >>
>> >> So, now you don't like this?  After it's become a standard?  Ick.
>> >>
>> >> Becides, /debug/ is pretty presumptious, it's as if debugging the kernel
>> >> is a system-wide thing :)
>> >>
>> >> So please, don't use /debug/ use the standard, defined, and ACTUALLY
>> >> USED BY DISTROS TODAY mount point of /sys/kernel/debug/
>> >>
>> >> If you want to create your own symlink from /debug/ to that location to
>> >> make it easier to type, feel free, but do not hard code any scripts to
>> >> use that location, or they are going to break.
>> >
>> > All my scripts search /proc/mounts to find where debugfs is mounted, then
>> > it uses that.
>> >
>> > Hmm, Not sure what packages in the distros use the default. I don't see
>> > the debugfs in /etc/fstab in any of my machines.
>> >
>> Yes.. In my case, I use linux distributions like Ubuntu 8.10, Fedora
>> 9/10, CENTOS 5.3 currently. This distributions  use proc , tmpfs,
>> devpts, sysfs for official release
>> by default.
>>
>
> The key thing is not to have scripts depend on a path. When debugfs is
> enabled in a kernel, you automatically get /sys/kernel/debug, so that is a
> natural place to mount it.
>
> I have also suggested to people (as Greg suggested earlier to me) that you
> can mount it there and then make a soft link to it. Which also works.
>
> I personally just mount it at /debug.
>
> To handle the scripts problem, all my scripts start with:
>
> # grep debugfs /proc/mounts | cut -d ' ' -f 2
>
> I also have a C function to do a search for debugfs in /proc/mounts.
>
> If you look in Documentation/trace/ftrace.txt I have:
>
> ===
> To mount the debugfs system:
>
>  # mkdir /debug
>  # mount -t debugfs nodev /debug
>
> ( Note: it is more common to mount at /sys/kernel/debug, but for
>  simplicity this document will use /debug)
> ===
>
> Thus it is a personal preference of mine to put it at /debug. But I do not
> hide the fact that it is recommended to be in /sys/kernel/debug. Heck, I'm
> the one that brought to light that path in this thread. I just curse it
> everytime I have to say it ;-)

Thank you for explanation about history of  "/debug/" and "/sys/kernel/debug/"
in the ./Documentations/trace/ftrace.txt file.

Do I have to change contents of patch file from "/debug/***" to "debug/***"
to consider both "/debug/"directory and
"/sys/kernel/debug/ (initial directory by debugfs)" directory in the
my patch file?

Or,
Do I have to keep  "/"  character of "/debug" in my patch file that I proposed
because many contributors  already use  "/debugfs/" or "/debug/"
in their patch files?

Steven, Can you advise me?

>
> -- Steve
>



-- 
Regards,
GeunSik Lim ( SAMSUNG ELECTRONICS)
Blog : http://blog.naver.com/invain/
e-Mail: geunsik.lim@samsung.com
           leemgs@gmail.com , leemgs1@gmail.com
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Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Jaswinder Singh Rajput]

Hello Steve,

On Tue, 2009-05-26 at 22:38 -0400, Steven Rostedt wrote:

> If you look in Documentation/trace/ftrace.txt I have:
> 
> ===
> To mount the debugfs system:
> 
>   # mkdir /debug
>   # mount -t debugfs nodev /debug
> 
> ( Note: it is more common to mount at /sys/kernel/debug, but for
>   simplicity this document will use /debug)
> ===
> 

Please standardize Documentation/trace/ftrace.txt and avoid confusion to
users:

===
To mount the debugfs system:

  # mount -t debugfs nodev /sys/kernel/debug
===

Thanks,
--
JSR

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Wed, 27 May 2009, Jaswinder Singh Rajput wrote:

> Hello Steve,
> 
> On Tue, 2009-05-26 at 22:38 -0400, Steven Rostedt wrote:
> 
> > If you look in Documentation/trace/ftrace.txt I have:
> > 
> > ===
> > To mount the debugfs system:
> > 
> >   # mkdir /debug
> >   # mount -t debugfs nodev /debug
> > 
> > ( Note: it is more common to mount at /sys/kernel/debug, but for
> >   simplicity this document will use /debug)
> > ===
> > 
> 
> Please standardize Documentation/trace/ftrace.txt and avoid confusion to
> users:
> 
> ===
> To mount the debugfs system:
> 
>   # mount -t debugfs nodev /sys/kernel/debug
> ===

I really don't want to do that. Then I would need to show

 # echo function_graph > /sys/kernel/debug/current_trace

Which I really do not like. I state that the common place to mount it is 
in /sys/kernel/debug, But my examples are much easier to understand if
I just do: # echo function_graph > /debug/current_trace

-- Steve

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Greg KH]

On Wed, May 27, 2009 at 02:22:37PM -0400, Steven Rostedt wrote:
> 
> On Wed, 27 May 2009, Jaswinder Singh Rajput wrote:
> 
> > Hello Steve,
> > 
> > On Tue, 2009-05-26 at 22:38 -0400, Steven Rostedt wrote:
> > 
> > > If you look in Documentation/trace/ftrace.txt I have:
> > > 
> > > ===
> > > To mount the debugfs system:
> > > 
> > >   # mkdir /debug
> > >   # mount -t debugfs nodev /debug
> > > 
> > > ( Note: it is more common to mount at /sys/kernel/debug, but for
> > >   simplicity this document will use /debug)
> > > ===
> > > 
> > 
> > Please standardize Documentation/trace/ftrace.txt and avoid confusion to
> > users:
> > 
> > ===
> > To mount the debugfs system:
> > 
> >   # mount -t debugfs nodev /sys/kernel/debug
> > ===
> 
> I really don't want to do that. Then I would need to show
> 
>  # echo function_graph > /sys/kernel/debug/current_trace
> 
> Which I really do not like. I state that the common place to mount it is 
> in /sys/kernel/debug, But my examples are much easier to understand if
> I just do: # echo function_graph > /debug/current_trace

It's not just the "common" place, it is the DOCUMENTED PLACE.

I'm sorry you have to type a long path, perhaps you wish to invest in a
tab key for auto-completion :)

Again, distros already mount debugfs at this location, please don't
confuse people just because you are annoyed at the length of the path.

thanks,

greg k-h

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Wed, 27 May 2009, Greg KH wrote:
> > > > 
> > > > ( Note: it is more common to mount at /sys/kernel/debug, but for
> > > >   simplicity this document will use /debug)
> > > > ===

> > 
> > I really don't want to do that. Then I would need to show
> > 
> >  # echo function_graph > /sys/kernel/debug/current_trace
> > 
> > Which I really do not like. I state that the common place to mount it is 
> > in /sys/kernel/debug, But my examples are much easier to understand if
> > I just do: # echo function_graph > /debug/current_trace
> 
> It's not just the "common" place, it is the DOCUMENTED PLACE.

I can change the wording to be "documented" or "distro mounted".

> 
> I'm sorry you have to type a long path, perhaps you wish to invest in a
> tab key for auto-completion :)
> 
> Again, distros already mount debugfs at this location, please don't
> confuse people just because you are annoyed at the length of the path.

Have you found which packages do that?

The point is that the document is more interested in showing the files 
that are being used, and if I add /sys/kernel/debug/ in front of every 
file, that just distracts from the eye. As stated:

  "but for simplicity this document will use /debug"

I'll update ftrace.txt to explain it better.

Something like:

=====
Debugfs is mounted by some packages at /sys/kernel/debugfs. If it is not 
you can mount it by adding

 debugfs   /sys/kernel/debug  debugfs   defaults   0   0

to your /etc/fstab, or by manually mounting it:

 # mount -t debugfs nodev /sys/kernel/debugfs

For simplicity, this document will assume that you also added the 
following symbolic link:

 # ln -s /sys/kernel/debugfs /debug
=====

Then I can keep the document simplistic and still have the "DOCUMENTED" 
locating specified.

-- Steve

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Greg KH]

On Thu, May 28, 2009 at 09:45:51AM -0400, Steven Rostedt wrote:
> > I'm sorry you have to type a long path, perhaps you wish to invest in a
> > tab key for auto-completion :)
> > 
> > Again, distros already mount debugfs at this location, please don't
> > confuse people just because you are annoyed at the length of the path.
> 
> Have you found which packages do that?

The base system packages on all openSUSE and SLE11 releases.  Possibly
SLE10 also does it, but I don't have a running instance of that at the
moment.

> The point is that the document is more interested in showing the files 
> that are being used, and if I add /sys/kernel/debug/ in front of every 
> file, that just distracts from the eye. As stated:
> 
>   "but for simplicity this document will use /debug"

Sorry for the "distraction", but that goes against documentation on your
machine:
	$ man mount | grep -A 3 "Mount options for debugfs"
	Mount options for debugfs
	       The debugfs file system is a pseudo file system, traditionally  mounted
	       on /sys/kernel/debug.  There are no mount options.

It's not only a documented standard, it's a "tradition" :)

Please fix your documentation.

thanks,

greg k-h

Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

On Thu, May 28, 2009 at 10:45 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Wed, 27 May 2009, Greg KH wrote:
>> > > >
>> > > > ( Note: it is more common to mount at /sys/kernel/debug, but for
>> > > >   simplicity this document will use /debug)
>> > > > ===
>
>> >
>> > I really don't want to do that. Then I would need to show
>> >
>> >  # echo function_graph > /sys/kernel/debug/current_trace
>> >
>> > Which I really do not like. I state that the common place to mount it is
>> > in /sys/kernel/debug, But my examples are much easier to understand if
>> > I just do: # echo function_graph > /debug/current_trace
>>
>> It's not just the "common" place, it is the DOCUMENTED PLACE.
>
> I can change the wording to be "documented" or "distro mounted".
>
>>
>> I'm sorry you have to type a long path, perhaps you wish to invest in a
>> tab key for auto-completion :)
>>
>> Again, distros already mount debugfs at this location, please don't
>> confuse people just because you are annoyed at the length of the path.
>
> Have you found which packages do that?
>
> The point is that the document is more interested in showing the files
> that are being used, and if I add /sys/kernel/debug/ in front of every
> file, that just distracts from the eye. As stated:
>
>  "but for simplicity this document will use /debug"
>
> I'll update ftrace.txt to explain it better.
Thank you for the decision to update  debufs filesystem realted contents.
>
> Something like:
>
> =====
> Debugfs is mounted by some packages at /sys/kernel/debugfs. If it is not
> you can mount it by adding
>
>  debugfs   /sys/kernel/debug  debugfs   defaults   0   0
>
> to your /etc/fstab, or by manually mounting it:
>
>  # mount -t debugfs nodev /sys/kernel/debugfs
>
> For simplicity, this document will assume that you also added the
> following symbolic link:
>
>  # ln -s /sys/kernel/debugfs /debug
> =====
About typo in the above statements.
/sys/kernel/debugfs --> /sys/kenrel/debug
Default directory of debugfs filesystem is /sys/kernel/debug/ as you know.

>
> Then I can keep the document simplistic and still have the "DOCUMENTED"
> locating specified.
>
> -- Steve
>
>



-- 
Regards,
GeunSik Lim ( SAMSUNG ELECTRONICS)
Blog : http://blog.naver.com/invain/
e-Mail: geunsik.lim@samsung.com
           leemgs@gmail.com , leemgs1@gmail.com
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[RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

Dear Greg and Steen,

Thanks your advices and opinions about a confusion according to  
too many mount directory names for debugfs. I made rfc v2 patch file again like belows.
Can I hear your advices about below patch contents?.  

* ref: 
http://groups.google.com/group/linux.kernel/browse_thread/thread/c34e386587979340/dc52317f888e78b6?#dc52317f888e78b6


Regards,
GeunSik Lim.

Subject: [PATCH]   Fix terminology inconsistency of dir name to mount debugfs filesystem.

      Many developers use "/debug/" or "/debugfs/ directory name to mount
      debugfs filesystem for ftrace according to
      ./Documentation/tracers/ftrace.txt file.

      And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
      existed in kernel source like ftrace, DRM, Wireless, Network[sky2]files
      to mount debugfs filesystem.

      debugfs means debug filesystem for debugging easy to use by greg kroah
      hartman. "/sys/kernel/debug/" name is suitable as directory name
      of debugfs filesystem.
      -debugfs related reference: http://lwn.net/Articles/115405/

      Fix inconsistency of directory name to mount debugfs filesystem.

         Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
         Acked-By: Inaky Perez-Gonzalez <inaky@linux.intel.com>
         CC: Greg KH <greg@kroah.com>
         CC: Steven Rostedt <rostedt@goodmis.org>
         CC: linux-kernel <linux-kernel@vger.kernel.org>
---
 Documentation/DocBook/debugobjects.tmpl           |    2 +-
 Documentation/cdrom/packet-writing.txt            |    2 +-
 Documentation/fault-injection/fault-injection.txt |   70 +++++-----
 Documentation/kprobes.txt                         |    6 +-
 Documentation/trace/ftrace.txt                    |  166 ++++++++++----------
 Documentation/trace/mmiotrace.txt                 |   26 ++--
 drivers/block/pktcdvd.c                           |    2 +-
 drivers/gpu/drm/drm_debugfs.c                     |   12 +-
 drivers/gpu/drm/drm_drv.c                         |    2 +-
 drivers/gpu/drm/drm_stub.c                        |    2 +-
 drivers/net/Kconfig                               |    4 +-
 drivers/net/wimax/i2400m/i2400m.h                 |    2 +-
 drivers/net/wireless/ath5k/Kconfig                |    6 +-
 drivers/net/wireless/libertas/README              |   12 +-
 drivers/scsi/lpfc/lpfc_debugfs.c                  |    4 +-
 include/linux/kernel.h                            |    2 +-
 include/linux/tracepoint.h                        |    4 +-
 kernel/trace/Kconfig                              |   10 +-
 kernel/trace/trace.c                              |   24 ++--
 scripts/tracing/draw_functrace.py                 |    8 +-
 20 files changed, 183 insertions(+), 183 deletions(-)

diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl
index 7f5f218..08ff908 100644
--- a/Documentation/DocBook/debugobjects.tmpl
+++ b/Documentation/DocBook/debugobjects.tmpl
@@ -106,7 +106,7 @@
       number of errors are printk'ed including a full stack trace.
     </para>
     <para>
-      The statistics are available via debugfs/debug_objects/stats.
+      The statistics are available via /sys/kernel/debug/debug_objects/stats.
       They provide information about the number of warnings and the
       number of successful fixups along with information about the
       usage of the internal tracking objects and the state of the
diff --git a/Documentation/cdrom/packet-writing.txt b/Documentation/cdrom/packet-writing.txt
index cf1f812..1c40777 100644
--- a/Documentation/cdrom/packet-writing.txt
+++ b/Documentation/cdrom/packet-writing.txt
@@ -117,7 +117,7 @@ Using the pktcdvd debugfs interface
 
 To read pktcdvd device infos in human readable form, do:
 
-	# cat /debug/pktcdvd/pktcdvd[0-7]/info
+	# cat /sys/kernel/debug/pktcdvd/pktcdvd[0-7]/info
 
 For a description of the debugfs interface look into the file:
 
diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt
index 4bc374a..0793056 100644
--- a/Documentation/fault-injection/fault-injection.txt
+++ b/Documentation/fault-injection/fault-injection.txt
@@ -29,16 +29,16 @@ o debugfs entries
 fault-inject-debugfs kernel module provides some debugfs entries for runtime
 configuration of fault-injection capabilities.
 
-- /debug/fail*/probability:
+- /sys/kernel/debug/fail*/probability:
 
 	likelihood of failure injection, in percent.
 	Format: <percent>
 
 	Note that one-failure-per-hundred is a very high error rate
 	for some testcases.  Consider setting probability=100 and configure
-	/debug/fail*/interval for such testcases.
+	/sys/kernel/debug/fail*/interval for such testcases.
 
-- /debug/fail*/interval:
+- /sys/kernel/debug/fail*/interval:
 
 	specifies the interval between failures, for calls to
 	should_fail() that pass all the other tests.
@@ -46,18 +46,18 @@ configuration of fault-injection capabilities.
 	Note that if you enable this, by setting interval>1, you will
 	probably want to set probability=100.
 
-- /debug/fail*/times:
+- /sys/kernel/debug/fail*/times:
 
 	specifies how many times failures may happen at most.
 	A value of -1 means "no limit".
 
-- /debug/fail*/space:
+- /sys/kernel/debug/fail*/space:
 
 	specifies an initial resource "budget", decremented by "size"
 	on each call to should_fail(,size).  Failure injection is
 	suppressed until "space" reaches zero.
 
-- /debug/fail*/verbose
+- /sys/kernel/debug/fail*/verbose
 
 	Format: { 0 | 1 | 2 }
 	specifies the verbosity of the messages when failure is
@@ -65,17 +65,17 @@ configuration of fault-injection capabilities.
 	log line per failure; '2' will print a call trace too -- useful
 	to debug the problems revealed by fault injection.
 
-- /debug/fail*/task-filter:
+- /sys/kernel/debug/fail*/task-filter:
 
 	Format: { 'Y' | 'N' }
 	A value of 'N' disables filtering by process (default).
 	Any positive value limits failures to only processes indicated by
 	/proc/<pid>/make-it-fail==1.
 
-- /debug/fail*/require-start:
-- /debug/fail*/require-end:
-- /debug/fail*/reject-start:
-- /debug/fail*/reject-end:
+- /sys/kernel/debug/fail*/require-start:
+- /sys/kernel/debug/fail*/require-end:
+- /sys/kernel/debug/fail*/reject-start:
+- /sys/kernel/debug/fail*/reject-end:
 
 	specifies the range of virtual addresses tested during
 	stacktrace walking.  Failure is injected only if some caller
@@ -84,26 +84,26 @@ configuration of fault-injection capabilities.
 	Default required range is [0,ULONG_MAX) (whole of virtual address space).
 	Default rejected range is [0,0).
 
-- /debug/fail*/stacktrace-depth:
+- /sys/kernel/debug/fail*/stacktrace-depth:
 
 	specifies the maximum stacktrace depth walked during search
 	for a caller within [require-start,require-end) OR
 	[reject-start,reject-end).
 
-- /debug/fail_page_alloc/ignore-gfp-highmem:
+- /sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:
 
 	Format: { 'Y' | 'N' }
 	default is 'N', setting it to 'Y' won't inject failures into
 	highmem/user allocations.
 
-- /debug/failslab/ignore-gfp-wait:
-- /debug/fail_page_alloc/ignore-gfp-wait:
+- /sys/kernel/debug/failslab/ignore-gfp-wait:
+- /sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:
 
 	Format: { 'Y' | 'N' }
 	default is 'N', setting it to 'Y' will inject failures
 	only into non-sleep allocations (GFP_ATOMIC allocations).
 
-- /debug/fail_page_alloc/min-order:
+- /sys/kernel/debug/fail_page_alloc/min-order:
 
 	specifies the minimum page allocation order to be injected
 	failures.
@@ -166,13 +166,13 @@ o Inject slab allocation failures into module init/exit code
 #!/bin/bash
 
 FAILTYPE=failslab
-echo Y > /debug/$FAILTYPE/task-filter
-echo 10 > /debug/$FAILTYPE/probability
-echo 100 > /debug/$FAILTYPE/interval
-echo -1 > /debug/$FAILTYPE/times
-echo 0 > /debug/$FAILTYPE/space
-echo 2 > /debug/$FAILTYPE/verbose
-echo 1 > /debug/$FAILTYPE/ignore-gfp-wait
+echo Y > /sys/kernel/debug/$FAILTYPE/task-filter
+echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+echo -1 > /sys/kernel/debug/$FAILTYPE/times
+echo 0 > /sys/kernel/debug/$FAILTYPE/space
+echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
 
 faulty_system()
 {
@@ -217,20 +217,20 @@ then
 	exit 1
 fi
 
-cat /sys/module/$module/sections/.text > /debug/$FAILTYPE/require-start
-cat /sys/module/$module/sections/.data > /debug/$FAILTYPE/require-end
+cat /sys/module/$module/sections/.text > /sys/kernel/debug/$FAILTYPE/require-start
+cat /sys/module/$module/sections/.data > /sys/kernel/debug/$FAILTYPE/require-end
 
-echo N > /debug/$FAILTYPE/task-filter
-echo 10 > /debug/$FAILTYPE/probability
-echo 100 > /debug/$FAILTYPE/interval
-echo -1 > /debug/$FAILTYPE/times
-echo 0 > /debug/$FAILTYPE/space
-echo 2 > /debug/$FAILTYPE/verbose
-echo 1 > /debug/$FAILTYPE/ignore-gfp-wait
-echo 1 > /debug/$FAILTYPE/ignore-gfp-highmem
-echo 10 > /debug/$FAILTYPE/stacktrace-depth
+echo N > /sys/kernel/debug/$FAILTYPE/task-filter
+echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+echo -1 > /sys/kernel/debug/$FAILTYPE/times
+echo 0 > /sys/kernel/debug/$FAILTYPE/space
+echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
+echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth
 
-trap "echo 0 > /debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
+trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
 
 echo "Injecting errors into the module $module... (interrupt to stop)"
 sleep 1000000
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt
index 1e7a769..053037a 100644
--- a/Documentation/kprobes.txt
+++ b/Documentation/kprobes.txt
@@ -507,9 +507,9 @@ http://www.linuxsymposium.org/2006/linuxsymposium_procv2.pdf (pages 101-115)
 Appendix A: The kprobes debugfs interface
 
 With recent kernels (> 2.6.20) the list of registered kprobes is visible
-under the /debug/kprobes/ directory (assuming debugfs is mounted at /debug).
+under the /sys/kernel/debug/kprobes/ directory (assuming debugfs is mounted at //sys/kernel/debug).
 
-/debug/kprobes/list: Lists all registered probes on the system
+/sys/kernel/debug/kprobes/list: Lists all registered probes on the system
 
 c015d71a  k  vfs_read+0x0
 c011a316  j  do_fork+0x0
@@ -525,7 +525,7 @@ virtual addresses that correspond to modules that've been unloaded),
 such probes are marked with [GONE]. If the probe is temporarily disabled,
 such probes are marked with [DISABLED].
 
-/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
+/sys/kernel/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
 
 Provides a knob to globally and forcibly turn registered kprobes ON or OFF.
 By default, all kprobes are enabled. By echoing "0" to this file, all
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..cbc6cca 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -35,11 +35,11 @@ well as the files to display output.
 
 To mount the debugfs system:
 
-  # mkdir /debug
-  # mount -t debugfs nodev /debug
+  # mkdir /sys/kernel/debug
+  # mount -t debugfs nodev /sys/kernel/debug
 
 ( Note: it is more common to mount at /sys/kernel/debug, but for
-  simplicity this document will use /debug)
+  simplicity this document will use /sys/kernel/debug)
 
 That's it! (assuming that you have ftrace configured into your kernel)
 
@@ -389,18 +389,18 @@ trace_options
 The trace_options file is used to control what gets printed in
 the trace output. To see what is available, simply cat the file:
 
-  cat /debug/tracing/trace_options
+  cat /sys/kernel/debug/tracing/trace_options
   print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
   noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj
 
 To disable one of the options, echo in the option prepended with
 "no".
 
-  echo noprint-parent > /debug/tracing/trace_options
+  echo noprint-parent > /sys/kernel/debug/tracing/trace_options
 
 To enable an option, leave off the "no".
 
-  echo sym-offset > /debug/tracing/trace_options
+  echo sym-offset > /sys/kernel/debug/tracing/trace_options
 
 Here are the available options:
 
@@ -476,11 +476,11 @@ sched_switch
 This tracer simply records schedule switches. Here is an example
 of how to use it.
 
- # echo sched_switch > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo sched_switch > /sys/kernel/debug/tracing/current_tracer
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/trace
 
 # tracer: sched_switch
 #
@@ -574,13 +574,13 @@ new trace is saved.
 To reset the maximum, echo 0 into tracing_max_latency. Here is
 an example:
 
- # echo irqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo irqsoff > /sys/kernel/debug/tracing/current_tracer
+ # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/latency_trace
 # tracer: irqsoff
 #
 irqsoff latency trace v1.1.5 on 2.6.26
@@ -681,13 +681,13 @@ Like the irqsoff tracer, it records the maximum latency for
 which preemption was disabled. The control of preemptoff tracer
 is much like the irqsoff tracer.
 
- # echo preemptoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptoff > /sys/kernel/debug/tracing/current_tracer
+ # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/latency_trace
 # tracer: preemptoff
 #
 preemptoff latency trace v1.1.5 on 2.6.26-rc8
@@ -828,13 +828,13 @@ tracer.
 Again, using this trace is much like the irqsoff and preemptoff
 tracers.
 
- # echo preemptirqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptirqsoff > /sys/kernel/debug/tracing/current_tracer
+ # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/latency_trace
 # tracer: preemptirqsoff
 #
 preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
@@ -990,12 +990,12 @@ slightly differently than we did with the previous tracers.
 Instead of performing an 'ls', we will run 'sleep 1' under
 'chrt' which changes the priority of the task.
 
- # echo wakeup > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo wakeup > /sys/kernel/debug/tracing/current_tracer
+ # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # chrt -f 5 sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/latency_trace
 # tracer: wakeup
 #
 wakeup latency trace v1.1.5 on 2.6.26-rc8
@@ -1105,11 +1105,11 @@ can be done from the debug file system. Make sure the
 ftrace_enabled is set; otherwise this tracer is a nop.
 
  # sysctl kernel.ftrace_enabled=1
- # echo function > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo function > /sys/kernel/debug/tracing/current_tracer
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1146,7 +1146,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1155,7 +1155,7 @@ int main(int argc, char *argv[]) {
 }
 
 Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
+guaranteed to be at /sys/kernel/debug (and is more commonly at
 /sys/kernel/debug). For simple one time traces, the above is
 sufficent. For anything else, a search through /proc/mounts may
 be needed to find where the debugfs file-system is mounted.
@@ -1164,16 +1164,16 @@ be needed to find where the debugfs file-system is mounted.
 Single thread tracing
 ---------------------
 
-By writing into /debug/tracing/set_ftrace_pid you can trace a
+By writing into /sys/kernel/debug/tracing/set_ftrace_pid you can trace a
 single thread. For example:
 
-# cat /debug/tracing/set_ftrace_pid
+# cat /sys/kernel/debug/tracing/set_ftrace_pid
 no pid
-# echo 3111 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/set_ftrace_pid
+# echo 3111 > /sys/kernel/debug/tracing/set_ftrace_pid
+# cat /sys/kernel/debug/tracing/set_ftrace_pid
 3111
-# echo function > /debug/tracing/current_tracer
-# cat /debug/tracing/trace | head
+# echo function > /sys/kernel/debug/tracing/current_tracer
+# cat /sys/kernel/debug/tracing/trace | head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1184,8 +1184,8 @@ no pid
      yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base <-hrtimer_try_to_cancel
      yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
      yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
-# echo -1 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/trace |head
+# echo -1 > /sys/kernel/debug/tracing/set_ftrace_pid
+# cat /sys/kernel/debug/tracing/trace |head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1217,12 +1217,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;
 
-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd = open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);
 
-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid", O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);
 
@@ -1374,22 +1374,22 @@ want, depending on your needs.
   tracing_cpu_mask file) or you might sometimes see unordered
   function calls while cpu tracing switch.
 
-	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
-	show: echo funcgraph-cpu > /debug/tracing/trace_options
+	hide: echo nofuncgraph-cpu > /sys/kernel/debug/tracing/trace_options
+	show: echo funcgraph-cpu > /sys/kernel/debug/tracing/trace_options
 
 - The duration (function's time of execution) is displayed on
   the closing bracket line of a function or on the same line
   than the current function in case of a leaf one. It is default
   enabled.
 
-	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
-	show: echo funcgraph-duration > /debug/tracing/trace_options
+	hide: echo nofuncgraph-duration > /sys/kernel/debug/tracing/trace_options
+	show: echo funcgraph-duration > /sys/kernel/debug/tracing/trace_options
 
 - The overhead field precedes the duration field in case of
   reached duration thresholds.
 
-	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
-	show: echo funcgraph-overhead > /debug/tracing/trace_options
+	hide: echo nofuncgraph-overhead > /sys/kernel/debug/tracing/trace_options
+	show: echo funcgraph-overhead > /sys/kernel/debug/tracing/trace_options
 	depends on: funcgraph-duration
 
   ie:
@@ -1418,8 +1418,8 @@ want, depending on your needs.
 - The task/pid field displays the thread cmdline and pid which
   executed the function. It is default disabled.
 
-	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
-	show: echo funcgraph-proc > /debug/tracing/trace_options
+	hide: echo nofuncgraph-proc > /sys/kernel/debug/tracing/trace_options
+	show: echo funcgraph-proc > /sys/kernel/debug/tracing/trace_options
 
   ie:
 
@@ -1442,8 +1442,8 @@ want, depending on your needs.
   system clock since it started. A snapshot of this time is
   given on each entry/exit of functions
 
-	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
-	show: echo funcgraph-abstime > /debug/tracing/trace_options
+	hide: echo nofuncgraph-abstime > /sys/kernel/debug/tracing/trace_options
+	show: echo funcgraph-abstime > /sys/kernel/debug/tracing/trace_options
 
   ie:
 
@@ -1540,7 +1540,7 @@ listed in:
 
    available_filter_functions
 
- # cat /debug/tracing/available_filter_functions
+ # cat /sys/kernel/debug/tracing/available_filter_functions
 put_prev_task_idle
 kmem_cache_create
 pick_next_task_rt
@@ -1552,12 +1552,12 @@ mutex_lock
 If I am only interested in sys_nanosleep and hrtimer_interrupt:
 
  # echo sys_nanosleep hrtimer_interrupt \
-		> /debug/tracing/set_ftrace_filter
- # echo ftrace > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+		> /sys/kernel/debug/tracing/set_ftrace_filter
+ # echo ftrace > /sys/kernel/debug/tracing/current_tracer
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/trace
 # tracer: ftrace
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1568,7 +1568,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt:
 
 To see which functions are being traced, you can cat the file:
 
- # cat /debug/tracing/set_ftrace_filter
+ # cat /sys/kernel/debug/tracing/set_ftrace_filter
 hrtimer_interrupt
 sys_nanosleep
 
@@ -1588,7 +1588,7 @@ Note: It is better to use quotes to enclose the wild cards,
       otherwise the shell may expand the parameters into names
       of files in the local directory.
 
- # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' > /sys/kernel/debug/tracing/set_ftrace_filter
 
 Produces:
 
@@ -1609,7 +1609,7 @@ Produces:
 
 Notice that we lost the sys_nanosleep.
 
- # cat /debug/tracing/set_ftrace_filter
+ # cat /sys/kernel/debug/tracing/set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1635,17 +1635,17 @@ To append to the filters, use '>>'
 To clear out a filter so that all functions will be recorded
 again:
 
- # echo > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo > /sys/kernel/debug/tracing/set_ftrace_filter
+ # cat /sys/kernel/debug/tracing/set_ftrace_filter
  #
 
 Again, now we want to append.
 
- # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo sys_nanosleep > /sys/kernel/debug/tracing/set_ftrace_filter
+ # cat /sys/kernel/debug/tracing/set_ftrace_filter
 sys_nanosleep
- # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' >> /sys/kernel/debug/tracing/set_ftrace_filter
+ # cat /sys/kernel/debug/tracing/set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1668,7 +1668,7 @@ hrtimer_init_sleeper
 The set_ftrace_notrace prevents those functions from being
 traced.
 
- # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+ # echo '*preempt*' '*lock*' > /sys/kernel/debug/tracing/set_ftrace_notrace
 
 Produces:
 
@@ -1758,13 +1758,13 @@ the effect on the tracing is different. Every read from
 trace_pipe is consumed. This means that subsequent reads will be
 different. The trace is live.
 
- # echo function > /debug/tracing/current_tracer
- # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+ # echo function > /sys/kernel/debug/tracing/current_tracer
+ # cat /sys/kernel/debug/tracing/trace_pipe > /tmp/trace.out &
 [1] 4153
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+ # cat /sys/kernel/debug/tracing/trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1800,7 +1800,7 @@ number listed is the number of entries that can be recorded per
 CPU. To know the full size, multiply the number of possible CPUS
 with the number of entries.
 
- # cat /debug/tracing/buffer_size_kb
+ # cat /sys/kernel/debug/tracing/buffer_size_kb
 1408 (units kilobytes)
 
 Note, to modify this, you must have tracing completely disabled.
@@ -1808,18 +1808,18 @@ To do that, echo "nop" into the current_tracer. If the
 current_tracer is not set to "nop", an EINVAL error will be
 returned.
 
- # echo nop > /debug/tracing/current_tracer
- # echo 10000 > /debug/tracing/buffer_size_kb
- # cat /debug/tracing/buffer_size_kb
+ # echo nop > /sys/kernel/debug/tracing/current_tracer
+ # echo 10000 > /sys/kernel/debug/tracing/buffer_size_kb
+ # cat /sys/kernel/debug/tracing/buffer_size_kb
 10000 (units kilobytes)
 
 The number of pages which will be allocated is limited to a
 percentage of available memory. Allocating too much will produce
 an error.
 
- # echo 1000000000000 > /debug/tracing/buffer_size_kb
+ # echo 1000000000000 > /sys/kernel/debug/tracing/buffer_size_kb
 -bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/buffer_size_kb
+ # cat /sys/kernel/debug/tracing/buffer_size_kb
 85
 
 -----------
diff --git a/Documentation/trace/mmiotrace.txt b/Documentation/trace/mmiotrace.txt
index 5731c67..162effb 100644
--- a/Documentation/trace/mmiotrace.txt
+++ b/Documentation/trace/mmiotrace.txt
@@ -32,41 +32,41 @@ is no way to automatically detect if you are losing events due to CPUs racing.
 Usage Quick Reference
 ---------------------
 
-$ mount -t debugfs debugfs /debug
-$ echo mmiotrace > /debug/tracing/current_tracer
-$ cat /debug/tracing/trace_pipe > mydump.txt &
+$ mount -t debugfs debugfs /sys/kernel/debug
+$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
+$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
 Start X or whatever.
-$ echo "X is up" > /debug/tracing/trace_marker
-$ echo nop > /debug/tracing/current_tracer
+$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
+$ echo nop > /sys/kernel/debug/tracing/current_tracer
 Check for lost events.
 
 
 Usage
 -----
 
-Make sure debugfs is mounted to /debug. If not, (requires root privileges)
-$ mount -t debugfs debugfs /debug
+Make sure debugfs is mounted to /sys/kernel/debug. If not, (requires root privileges)
+$ mount -t debugfs debugfs /sys/kernel/debug
 
 Check that the driver you are about to trace is not loaded.
 
 Activate mmiotrace (requires root privileges):
-$ echo mmiotrace > /debug/tracing/current_tracer
+$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
 
 Start storing the trace:
-$ cat /debug/tracing/trace_pipe > mydump.txt &
+$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
 The 'cat' process should stay running (sleeping) in the background.
 
 Load the driver you want to trace and use it. Mmiotrace will only catch MMIO
 accesses to areas that are ioremapped while mmiotrace is active.
 
 During tracing you can place comments (markers) into the trace by
-$ echo "X is up" > /debug/tracing/trace_marker
+$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
 This makes it easier to see which part of the (huge) trace corresponds to
 which action. It is recommended to place descriptive markers about what you
 do.
 
 Shut down mmiotrace (requires root privileges):
-$ echo nop > /debug/tracing/current_tracer
+$ echo nop > /sys/kernel/debug/tracing/current_tracer
 The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
 pressing ctrl+c.
 
@@ -78,10 +78,10 @@ to view your kernel log and look for "mmiotrace has lost events" warning. If
 events were lost, the trace is incomplete. You should enlarge the buffers and
 try again. Buffers are enlarged by first seeing how large the current buffers
 are:
-$ cat /debug/tracing/buffer_size_kb
+$ cat /sys/kernel/debug/tracing/buffer_size_kb
 gives you a number. Approximately double this number and write it back, for
 instance:
-$ echo 128000 > /debug/tracing/buffer_size_kb
+$ echo 128000 > /sys/kernel/debug/tracing/buffer_size_kb
 Then start again from the top.
 
 If you are doing a trace for a driver project, e.g. Nouveau, you should also
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index dc7a8c3..9aa8932 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -430,7 +430,7 @@ static void pkt_sysfs_cleanup(void)
 /********************************************************************
   entries in debugfs
 
-  /debugfs/pktcdvd[0-7]/
+  /sys/kernel/debug/pktcdvd[0-7]/
 			info
 
  *******************************************************************/
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index c77c6c6..6ce0e26 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -105,7 +105,7 @@ int drm_debugfs_create_files(struct drm_info_list *files, int count,
 		ent = debugfs_create_file(files[i].name, S_IFREG | S_IRUGO,
 					  root, tmp, &drm_debugfs_fops);
 		if (!ent) {
-			DRM_ERROR("Cannot create /debugfs/dri/%s/%s\n",
+			DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s/%s\n",
 				  name, files[i].name);
 			drm_free(tmp, sizeof(struct drm_info_node),
 				 _DRM_DRIVER);
@@ -133,9 +133,9 @@ EXPORT_SYMBOL(drm_debugfs_create_files);
  * \param minor device minor number
  * \param root DRI debugfs dir entry.
  *
- * Create the DRI debugfs root entry "/debugfs/dri", the device debugfs root entry
- * "/debugfs/dri/%minor%/", and each entry in debugfs_list as
- * "/debugfs/dri/%minor%/%name%".
+ * Create the DRI debugfs root entry "/sys/kernel/debug/dri", the device debugfs root entry
+ * "/sys/kernel/debug/dri/%minor%/", and each entry in debugfs_list as
+ * "/sys/kernel/debug/dri/%minor%/%name%".
  */
 int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		     struct dentry *root)
@@ -148,7 +148,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 	sprintf(name, "%d", minor_id);
 	minor->debugfs_root = debugfs_create_dir(name, root);
 	if (!minor->debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri/%s\n", name);
+		DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s\n", name);
 		return -1;
 	}
 
@@ -165,7 +165,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		ret = dev->driver->debugfs_init(minor);
 		if (ret) {
 			DRM_ERROR("DRM: Driver failed to initialize "
-				  "/debugfs/dri.\n");
+				  "/sys/kernel/debug/dri.\n");
 			return ret;
 		}
 	}
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 019b7c5..1bf7efd 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -339,7 +339,7 @@ static int __init drm_core_init(void)
 
 	drm_debugfs_root = debugfs_create_dir("dri", NULL);
 	if (!drm_debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri\n");
+		DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
 		ret = -1;
 		goto err_p3;
 	}
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index b9631e3..b2a93c4 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -328,7 +328,7 @@ static int drm_get_minor(struct drm_device *dev, struct drm_minor **minor, int t
 #if defined(CONFIG_DEBUG_FS)
 	ret = drm_debugfs_init(new_minor, minor_id, drm_debugfs_root);
 	if (ret) {
-		DRM_ERROR("DRM: Failed to initialize /debugfs/dri.\n");
+		DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
 		goto err_g2;
 	}
 #endif
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 214a92d..a170cea 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2200,7 +2200,7 @@ config SKGE_DEBUG
        depends on SKGE && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/skge/ethX displays the state of the internal
+	 The file /sys/kernel/debug/skge/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
@@ -2226,7 +2226,7 @@ config SKY2_DEBUG
        depends on SKY2 && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/sky2/ethX displays the state of the internal
+	 The file /sys/kernel/debug/sky2/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
diff --git a/drivers/net/wimax/i2400m/i2400m.h b/drivers/net/wimax/i2400m/i2400m.h
index 3ae2df3..da2e8f2 100644
--- a/drivers/net/wimax/i2400m/i2400m.h
+++ b/drivers/net/wimax/i2400m/i2400m.h
@@ -389,7 +389,7 @@ struct i2400m {
 	unsigned ready:1;		/* all probing steps done */
 	unsigned rx_reorder:1;		/* RX reorder is enabled */
 	u8 trace_msg_from_user;		/* echo rx msgs to 'trace' pipe */
-					/* typed u8 so debugfs/u8 can tweak */
+					/* typed u8 so /sys/kernel/debug/u8 can tweak */
 	enum i2400m_system_state state;
 	wait_queue_head_t state_wq;	/* Woken up when on state updates */
 
diff --git a/drivers/net/wireless/ath5k/Kconfig b/drivers/net/wireless/ath5k/Kconfig
index 75383a5..fdfa708 100644
--- a/drivers/net/wireless/ath5k/Kconfig
+++ b/drivers/net/wireless/ath5k/Kconfig
@@ -27,11 +27,11 @@ config ATH5K_DEBUG
 	  Say Y, if and you will get debug options for ath5k.
 	  To use this, you need to mount debugfs:
 
-	  mkdir /debug/
-	  mount -t debugfs debug /debug/
+	  mkdir /sys/kernel/debug/
+	  mount -t debugfs debug /sys/kernel/debug/
 
 	  You will get access to files under:
-	  /debug/ath5k/phy0/
+	  /sys/kernel/debug/ath5k/phy0/
 
 	  To enable debug, pass the debug level to the debug module
 	  parameter. For example:
diff --git a/drivers/net/wireless/libertas/README b/drivers/net/wireless/libertas/README
index d860fc3..ab6a2d5 100644
--- a/drivers/net/wireless/libertas/README
+++ b/drivers/net/wireless/libertas/README
@@ -72,7 +72,7 @@ rdrf
 	location that is to be read.  This parameter must be specified in
 	hexadecimal (its possible to preceed preceding the number with a "0x").
 
-	Path: /debugfs/libertas_wireless/ethX/registers/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/registers/
 
 	Usage:
 		echo "0xa123" > rdmac ; cat rdmac
@@ -95,7 +95,7 @@ wrrf
 sleepparams
 	This command is used to set the sleepclock configurations
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage:
 		cat sleepparams: reads the current sleepclock configuration
@@ -115,7 +115,7 @@ subscribed_events
 	The subscribed_events directory contains the interface for the
 	subscribed events API.
 
-	Path: /debugfs/libertas_wireless/ethX/subscribed_events/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/subscribed_events/
 
 	Each event is represented by a filename. Each filename consists of the
 	following three fields:
@@ -165,7 +165,7 @@ subscribed_events
 extscan
 	This command is used to do a specific scan.
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage: echo "SSID" > extscan
 
@@ -179,7 +179,7 @@ getscantable
 	Display the current contents of the driver scan table (ie. get the
 	scan results).
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage:
 		cat getscantable
@@ -188,7 +188,7 @@ setuserscan
 	Initiate a customized scan and retrieve the results
 
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
     Usage:
        echo "[ARGS]" > setuserscan
diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index 52be564..9112380 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -51,8 +51,8 @@
  * debugfs interface
  *
  * To access this interface the user should:
- * # mkdir /debug
- * # mount -t debugfs none /debug
+ * # mkdir /sys/kernel/debug
+ * # mount -t debugfs none /sys/kernel/debug
  *
  * The lpfc debugfs directory hierarchy is:
  * lpfc/lpfcX/vportY
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 883cd44..99b7aad 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -406,7 +406,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
  *
  * Use tracing_on/tracing_off when you want to quickly turn on or off
  * tracing. It simply enables or disables the recording of the trace events.
- * This also corresponds to the user space debugfs/tracing/tracing_on
+ * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
  * file, which gives a means for the kernel and userspace to interact.
  * Place a tracing_off() in the kernel where you want tracing to end.
  * From user space, examine the trace, and then echo 1 > tracing_on
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index d35a7ee..9c9ac7d 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -197,7 +197,7 @@ static inline void tracepoint_synchronize_unregister(void)
  *	* This is how the trace record is structured and will
  *	* be saved into the ring buffer. These are the fields
  *	* that will be exposed to user-space in
- *	* /debug/tracing/events/<*>/format.
+ *	* /sys/kernel/debug/tracing/events/<*>/format.
  *	*
  *	* The declared 'local variable' is called '__entry'
  *	*
@@ -257,7 +257,7 @@ static inline void tracepoint_synchronize_unregister(void)
  * tracepoint callback (this is used by programmatic plugins and
  * can also by used by generic instrumentation like SystemTap), and
  * it is also used to expose a structured trace record in
- * /debug/tracing/events/.
+ * /sys/kernel/debug/tracing/events/.
  */
 
 #define TRACE_EVENT(name, proto, args, struct, assign, print)	\
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 417d198..e5ce28f 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -120,7 +120,7 @@ config IRQSOFF_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the preempt-off timing option can be
@@ -141,7 +141,7 @@ config PREEMPT_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the irqs-off timing option can be
@@ -213,7 +213,7 @@ config TRACE_BRANCH_PROFILING
 	  This tracer profiles all the the likely and unlikely macros
 	  in the kernel. It will display the results in:
 
-	  /debugfs/tracing/profile_annotated_branch
+	  /sys/kernel/debug/tracing/profile_annotated_branch
 
 	  Note: this will add a significant overhead, only turn this
 	  on if you need to profile the system's use of these macros.
@@ -228,7 +228,7 @@ config PROFILE_ALL_BRANCHES
 	  taken in the kernel is recorded whether it hit or miss.
 	  The results will be displayed in:
 
-	  /debugfs/tracing/profile_branch
+	  /sys/kernel/debug/tracing/profile_branch
 
 	  This configuration, when enabled, will impose a great overhead
 	  on the system. This should only be enabled when the system
@@ -276,7 +276,7 @@ config STACK_TRACER
 	select KALLSYMS
 	help
 	  This special tracer records the maximum stack footprint of the
-	  kernel and displays it in debugfs/tracing/stack_trace.
+	  kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
 
 	  This tracer works by hooking into every function call that the
 	  kernel executes, and keeping a maximum stack depth value and
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index cda81ec..9b94d57 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -335,7 +335,7 @@ static raw_spinlock_t ftrace_max_lock =
 /*
  * Copy the new maximum trace into the separate maximum-trace
  * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /debugfs/tracing/latency_trace)
+ * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
  */
 static void
 __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
@@ -2366,21 +2366,21 @@ static const struct file_operations tracing_iter_fops = {
 
 static const char readme_msg[] =
 	"tracing mini-HOWTO:\n\n"
-	"# mkdir /debug\n"
-	"# mount -t debugfs nodev /debug\n\n"
-	"# cat /debug/tracing/available_tracers\n"
+	"# mkdir /sys/kernel/debug\n"
+	"# mount -t debugfs nodev /sys/kernel/debug\n\n"
+	"# cat /sys/kernel/debug/tracing/available_tracers\n"
 	"wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
-	"# cat /debug/tracing/current_tracer\n"
+	"# cat /sys/kernel/debug/tracing/current_tracer\n"
 	"nop\n"
-	"# echo sched_switch > /debug/tracing/current_tracer\n"
-	"# cat /debug/tracing/current_tracer\n"
+	"# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
+	"# cat /sys/kernel/debug/tracing/current_tracer\n"
 	"sched_switch\n"
-	"# cat /debug/tracing/trace_options\n"
+	"# cat /sys/kernel/debug/tracing/trace_options\n"
 	"noprint-parent nosym-offset nosym-addr noverbose\n"
-	"# echo print-parent > /debug/tracing/trace_options\n"
-	"# echo 1 > /debug/tracing/tracing_enabled\n"
-	"# cat /debug/tracing/trace > /tmp/trace.txt\n"
-	"# echo 0 > /debug/tracing/tracing_enabled\n"
+	"# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
+	"# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
+	"# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
+	"# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
 ;
 
 static ssize_t
diff --git a/scripts/tracing/draw_functrace.py b/scripts/tracing/draw_functrace.py
index 902f9a9..66f4d1b 100644
--- a/scripts/tracing/draw_functrace.py
+++ b/scripts/tracing/draw_functrace.py
@@ -12,10 +12,10 @@ calls. Only the functions's names and the the call time are provided.
 
 Usage:
 	Be sure that you have CONFIG_FUNCTION_TRACER
-	# mkdir /debugfs
-	# mount -t debug debug /debug
-	# echo function > /debug/tracing/current_tracer
-	$ cat /debug/tracing/trace_pipe > ~/raw_trace_func
+	# mkdir /sys/kernel/debug
+	# mount -t debug debug /sys/kernel/debug
+	# echo function > /sys/kernel/debug/tracing/current_tracer
+	$ cat /sys/kernel/debug/tracing/trace_pipe > ~/raw_trace_func
 	Wait some times but not too much, the script is a bit slow.
 	Break the pipe (Ctrl + Z)
 	$ scripts/draw_functrace.py < raw_trace_func > draw_functrace
-- 
1.6.3.1

 
-----------------------------------------------
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GeunSik Lim (  S A M S U N G     E L E C T R O N I C S  )
e-Mail  :1) geunsik.lim@samsung.com
         2) leemgs@gmail.com , leemgs1@gmail.com
HomePage: http://blog.naver.com/invain/
-----------------------------------------------

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Sat, 30 May 2009, GeunSik Lim wrote:
> diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
> index fd9a3e6..cbc6cca 100644
> --- a/Documentation/trace/ftrace.txt
> +++ b/Documentation/trace/ftrace.txt
> @@ -35,11 +35,11 @@ well as the files to display output.
>  
>  To mount the debugfs system:
>  
> -  # mkdir /debug
> -  # mount -t debugfs nodev /debug
> +  # mkdir /sys/kernel/debug

If you configure debugfs into the kernel, the directory /sys/kernel/debug 
will automatically be created. Remember, /sys is a psuedo filesystem as 
well.

> +  # mount -t debugfs nodev /sys/kernel/debug
>  
>  ( Note: it is more common to mount at /sys/kernel/debug, but for
> -  simplicity this document will use /debug)
> +  simplicity this document will use /sys/kernel/debug)

LOL!

>  
>  That's it! (assuming that you have ftrace configured into your kernel)
>  
> @@ -389,18 +389,18 @@ trace_options
>  The trace_options file is used to control what gets printed in
>  the trace output. To see what is available, simply cat the file:
>  
> -  cat /debug/tracing/trace_options
> +  cat /sys/kernel/debug/tracing/trace_options
>    print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
>    noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj
>  
>  To disable one of the options, echo in the option prepended with
>  "no".
>  
> -  echo noprint-parent > /debug/tracing/trace_options
> +  echo noprint-parent > /sys/kernel/debug/tracing/trace_options
>  
>  To enable an option, leave off the "no".
>  
> -  echo sym-offset > /debug/tracing/trace_options
> +  echo sym-offset > /sys/kernel/debug/tracing/trace_options
>  
>  Here are the available options:
>  
> @@ -476,11 +476,11 @@ sched_switch
>  This tracer simply records schedule switches. Here is an example
>  of how to use it.
>  
> - # echo sched_switch > /debug/tracing/current_tracer
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo sched_switch > /sys/kernel/debug/tracing/current_tracer
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # sleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/trace
>  
>  # tracer: sched_switch
>  #
> @@ -574,13 +574,13 @@ new trace is saved.
>  To reset the maximum, echo 0 into tracing_max_latency. Here is
>  an example:
>  
> - # echo irqsoff > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo irqsoff > /sys/kernel/debug/tracing/current_tracer
> + # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # ls -ltr
>   [...]
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/latency_trace
>  # tracer: irqsoff
>  #
>  irqsoff latency trace v1.1.5 on 2.6.26
> @@ -681,13 +681,13 @@ Like the irqsoff tracer, it records the maximum latency for
>  which preemption was disabled. The control of preemptoff tracer
>  is much like the irqsoff tracer.
>  
> - # echo preemptoff > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo preemptoff > /sys/kernel/debug/tracing/current_tracer
> + # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # ls -ltr
>   [...]
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/latency_trace
>  # tracer: preemptoff
>  #
>  preemptoff latency trace v1.1.5 on 2.6.26-rc8
> @@ -828,13 +828,13 @@ tracer.
>  Again, using this trace is much like the irqsoff and preemptoff
>  tracers.
>  
> - # echo preemptirqsoff > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo preemptirqsoff > /sys/kernel/debug/tracing/current_tracer
> + # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # ls -ltr
>   [...]
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/latency_trace
>  # tracer: preemptirqsoff
>  #
>  preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
> @@ -990,12 +990,12 @@ slightly differently than we did with the previous tracers.
>  Instead of performing an 'ls', we will run 'sleep 1' under
>  'chrt' which changes the priority of the task.
>  
> - # echo wakeup > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo wakeup > /sys/kernel/debug/tracing/current_tracer
> + # echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled

Egad! This is exactly why I hate the path name. It distracts so much from 
the eyes to what you want to accomplish. It seems that because it is a 
tradition to use this /sys/kernel/debug path, that I'm destine to fail in 
my discuss for it. I will ask that this document suggest the following at 
the beginning.

===
When debugfs is configured into the kernel (which selecting any ftrace 
option will do) the directory /sys/kernel/debug will be created. To mount 
this directory, you can add to your /etc/fstab file:

  debugfs	/debug		debugfs	defaults	0	0

Or you can mount it at run time with:

  mount -t debugfs nodev /sys/kernel/debug

For quicker access to that directory you may want to make a soft link to 
it:

 ln -s /sys/kernel/debug /debug

Any selected ftrace option will also create a directory called tracing 
within the debugfs. The rest of the document will assume that you are in 
the ftrace directory (cd /sys/kernel/debugfs) and will only concentrate
on the files within that directory and not distract from the content with 
the extended "/sys/kernel/debug/tracing" path name.
===

And then we can change all your other changes in this file as:

  s,/sys/kernel/debug/tracing,,


-- Steve

>   # chrt -f 5 sleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/latency_trace
>  # tracer: wakeup
>  #
>  wakeup latency trace v1.1.5 on 2.6.26-rc8
> @@ -1105,11 +1105,11 @@ can be done from the debug file system. Make sure the
>  ftrace_enabled is set; otherwise this tracer is a nop.
>  
>   # sysctl kernel.ftrace_enabled=1
> - # echo function > /debug/tracing/current_tracer
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo function > /sys/kernel/debug/tracing/current_tracer
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # usleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/trace
>  # tracer: function
>  #
>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
> @@ -1146,7 +1146,7 @@ int trace_fd;
>  [...]
>  int main(int argc, char *argv[]) {
>  	[...]
> -	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
> +	trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
>  	[...]
>  	if (condition_hit()) {
>  		write(trace_fd, "0", 1);
> @@ -1155,7 +1155,7 @@ int main(int argc, char *argv[]) {
>  }
>  
>  Note: Here we hard coded the path name. The debugfs mount is not
> -guaranteed to be at /debug (and is more commonly at
> +guaranteed to be at /sys/kernel/debug (and is more commonly at
>  /sys/kernel/debug). For simple one time traces, the above is
>  sufficent. For anything else, a search through /proc/mounts may
>  be needed to find where the debugfs file-system is mounted.
> @@ -1164,16 +1164,16 @@ be needed to find where the debugfs file-system is mounted.
>  Single thread tracing
>  ---------------------
>  
> -By writing into /debug/tracing/set_ftrace_pid you can trace a
> +By writing into /sys/kernel/debug/tracing/set_ftrace_pid you can trace a
>  single thread. For example:
>  
> -# cat /debug/tracing/set_ftrace_pid
> +# cat /sys/kernel/debug/tracing/set_ftrace_pid
>  no pid
> -# echo 3111 > /debug/tracing/set_ftrace_pid
> -# cat /debug/tracing/set_ftrace_pid
> +# echo 3111 > /sys/kernel/debug/tracing/set_ftrace_pid
> +# cat /sys/kernel/debug/tracing/set_ftrace_pid
>  3111
> -# echo function > /debug/tracing/current_tracer
> -# cat /debug/tracing/trace | head
> +# echo function > /sys/kernel/debug/tracing/current_tracer
> +# cat /sys/kernel/debug/tracing/trace | head
>   # tracer: function
>   #
>   #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
> @@ -1184,8 +1184,8 @@ no pid
>       yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base <-hrtimer_try_to_cancel
>       yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
>       yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
> -# echo -1 > /debug/tracing/set_ftrace_pid
> -# cat /debug/tracing/trace |head
> +# echo -1 > /sys/kernel/debug/tracing/set_ftrace_pid
> +# cat /sys/kernel/debug/tracing/trace |head
>   # tracer: function
>   #
>   #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
> @@ -1217,12 +1217,12 @@ int main (int argc, char **argv)
>                  char line[64];
>                  int s;
>  
> -                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
> +                ffd = open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
>                  if (ffd < 0)
>                          exit(-1);
>                  write(ffd, "nop", 3);
>  
> -                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
> +                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid", O_WRONLY);
>                  s = sprintf(line, "%d\n", getpid());
>                  write(fd, line, s);
>  
> @@ -1374,22 +1374,22 @@ want, depending on your needs.
>    tracing_cpu_mask file) or you might sometimes see unordered
>    function calls while cpu tracing switch.
>  
> -	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
> -	show: echo funcgraph-cpu > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-cpu > /sys/kernel/debug/tracing/trace_options
> +	show: echo funcgraph-cpu > /sys/kernel/debug/tracing/trace_options
>  
>  - The duration (function's time of execution) is displayed on
>    the closing bracket line of a function or on the same line
>    than the current function in case of a leaf one. It is default
>    enabled.
>  
> -	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
> -	show: echo funcgraph-duration > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-duration > /sys/kernel/debug/tracing/trace_options
> +	show: echo funcgraph-duration > /sys/kernel/debug/tracing/trace_options
>  
>  - The overhead field precedes the duration field in case of
>    reached duration thresholds.
>  
> -	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
> -	show: echo funcgraph-overhead > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-overhead > /sys/kernel/debug/tracing/trace_options
> +	show: echo funcgraph-overhead > /sys/kernel/debug/tracing/trace_options
>  	depends on: funcgraph-duration
>  
>    ie:
> @@ -1418,8 +1418,8 @@ want, depending on your needs.
>  - The task/pid field displays the thread cmdline and pid which
>    executed the function. It is default disabled.
>  
> -	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
> -	show: echo funcgraph-proc > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-proc > /sys/kernel/debug/tracing/trace_options
> +	show: echo funcgraph-proc > /sys/kernel/debug/tracing/trace_options
>  
>    ie:
>  
> @@ -1442,8 +1442,8 @@ want, depending on your needs.
>    system clock since it started. A snapshot of this time is
>    given on each entry/exit of functions
>  
> -	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
> -	show: echo funcgraph-abstime > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-abstime > /sys/kernel/debug/tracing/trace_options
> +	show: echo funcgraph-abstime > /sys/kernel/debug/tracing/trace_options
>  
>    ie:
>  
> @@ -1540,7 +1540,7 @@ listed in:
>  
>     available_filter_functions
>  
> - # cat /debug/tracing/available_filter_functions
> + # cat /sys/kernel/debug/tracing/available_filter_functions
>  put_prev_task_idle
>  kmem_cache_create
>  pick_next_task_rt
> @@ -1552,12 +1552,12 @@ mutex_lock
>  If I am only interested in sys_nanosleep and hrtimer_interrupt:
>  
>   # echo sys_nanosleep hrtimer_interrupt \
> -		> /debug/tracing/set_ftrace_filter
> - # echo ftrace > /debug/tracing/current_tracer
> - # echo 1 > /debug/tracing/tracing_enabled
> +		> /sys/kernel/debug/tracing/set_ftrace_filter
> + # echo ftrace > /sys/kernel/debug/tracing/current_tracer
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # usleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/trace
>  # tracer: ftrace
>  #
>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
> @@ -1568,7 +1568,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt:
>  
>  To see which functions are being traced, you can cat the file:
>  
> - # cat /debug/tracing/set_ftrace_filter
> + # cat /sys/kernel/debug/tracing/set_ftrace_filter
>  hrtimer_interrupt
>  sys_nanosleep
>  
> @@ -1588,7 +1588,7 @@ Note: It is better to use quotes to enclose the wild cards,
>        otherwise the shell may expand the parameters into names
>        of files in the local directory.
>  
> - # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
> + # echo 'hrtimer_*' > /sys/kernel/debug/tracing/set_ftrace_filter
>  
>  Produces:
>  
> @@ -1609,7 +1609,7 @@ Produces:
>  
>  Notice that we lost the sys_nanosleep.
>  
> - # cat /debug/tracing/set_ftrace_filter
> + # cat /sys/kernel/debug/tracing/set_ftrace_filter
>  hrtimer_run_queues
>  hrtimer_run_pending
>  hrtimer_init
> @@ -1635,17 +1635,17 @@ To append to the filters, use '>>'
>  To clear out a filter so that all functions will be recorded
>  again:
>  
> - # echo > /debug/tracing/set_ftrace_filter
> - # cat /debug/tracing/set_ftrace_filter
> + # echo > /sys/kernel/debug/tracing/set_ftrace_filter
> + # cat /sys/kernel/debug/tracing/set_ftrace_filter
>   #
>  
>  Again, now we want to append.
>  
> - # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
> - # cat /debug/tracing/set_ftrace_filter
> + # echo sys_nanosleep > /sys/kernel/debug/tracing/set_ftrace_filter
> + # cat /sys/kernel/debug/tracing/set_ftrace_filter
>  sys_nanosleep
> - # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
> - # cat /debug/tracing/set_ftrace_filter
> + # echo 'hrtimer_*' >> /sys/kernel/debug/tracing/set_ftrace_filter
> + # cat /sys/kernel/debug/tracing/set_ftrace_filter
>  hrtimer_run_queues
>  hrtimer_run_pending
>  hrtimer_init
> @@ -1668,7 +1668,7 @@ hrtimer_init_sleeper
>  The set_ftrace_notrace prevents those functions from being
>  traced.
>  
> - # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
> + # echo '*preempt*' '*lock*' > /sys/kernel/debug/tracing/set_ftrace_notrace
>  
>  Produces:
>  
> @@ -1758,13 +1758,13 @@ the effect on the tracing is different. Every read from
>  trace_pipe is consumed. This means that subsequent reads will be
>  different. The trace is live.
>  
> - # echo function > /debug/tracing/current_tracer
> - # cat /debug/tracing/trace_pipe > /tmp/trace.out &
> + # echo function > /sys/kernel/debug/tracing/current_tracer
> + # cat /sys/kernel/debug/tracing/trace_pipe > /tmp/trace.out &
>  [1] 4153
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo 1 > /sys/kernel/debug/tracing/tracing_enabled
>   # usleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > /sys/kernel/debug/tracing/tracing_enabled
> + # cat /sys/kernel/debug/tracing/trace
>  # tracer: function
>  #
>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
> @@ -1800,7 +1800,7 @@ number listed is the number of entries that can be recorded per
>  CPU. To know the full size, multiply the number of possible CPUS
>  with the number of entries.
>  
> - # cat /debug/tracing/buffer_size_kb
> + # cat /sys/kernel/debug/tracing/buffer_size_kb
>  1408 (units kilobytes)
>  
>  Note, to modify this, you must have tracing completely disabled.
> @@ -1808,18 +1808,18 @@ To do that, echo "nop" into the current_tracer. If the
>  current_tracer is not set to "nop", an EINVAL error will be
>  returned.
>  
> - # echo nop > /debug/tracing/current_tracer
> - # echo 10000 > /debug/tracing/buffer_size_kb
> - # cat /debug/tracing/buffer_size_kb
> + # echo nop > /sys/kernel/debug/tracing/current_tracer
> + # echo 10000 > /sys/kernel/debug/tracing/buffer_size_kb
> + # cat /sys/kernel/debug/tracing/buffer_size_kb
>  10000 (units kilobytes)
>  
>  The number of pages which will be allocated is limited to a
>  percentage of available memory. Allocating too much will produce
>  an error.
>  
> - # echo 1000000000000 > /debug/tracing/buffer_size_kb
> + # echo 1000000000000 > /sys/kernel/debug/tracing/buffer_size_kb
>  -bash: echo: write error: Cannot allocate memory
> - # cat /debug/tracing/buffer_size_kb
> + # cat /sys/kernel/debug/tracing/buffer_size_kb
>  85
>  
>  -----------
> diff --git a/Documentation/trace/mmiotrace.txt b/Documentation/trace/mmiotrace.txt
> index 5731c67..162effb 100644
> --- a/Documentation/trace/mmiotrace.txt
> +++ b/Documentation/trace/mmiotrace.txt
> @@ -32,41 +32,41 @@ is no way to automatically detect if you are losing events due to CPUs racing.
>  Usage Quick Reference
>  ---------------------
>  
> -$ mount -t debugfs debugfs /debug
> -$ echo mmiotrace > /debug/tracing/current_tracer
> -$ cat /debug/tracing/trace_pipe > mydump.txt &
> +$ mount -t debugfs debugfs /sys/kernel/debug
> +$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
> +$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
>  Start X or whatever.
> -$ echo "X is up" > /debug/tracing/trace_marker
> -$ echo nop > /debug/tracing/current_tracer
> +$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
> +$ echo nop > /sys/kernel/debug/tracing/current_tracer
>  Check for lost events.
>  
>  
>  Usage
>  -----
>  
> -Make sure debugfs is mounted to /debug. If not, (requires root privileges)
> -$ mount -t debugfs debugfs /debug
> +Make sure debugfs is mounted to /sys/kernel/debug. If not, (requires root privileges)
> +$ mount -t debugfs debugfs /sys/kernel/debug
>  
>  Check that the driver you are about to trace is not loaded.
>  
>  Activate mmiotrace (requires root privileges):
> -$ echo mmiotrace > /debug/tracing/current_tracer
> +$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
>  
>  Start storing the trace:
> -$ cat /debug/tracing/trace_pipe > mydump.txt &
> +$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
>  The 'cat' process should stay running (sleeping) in the background.
>  
>  Load the driver you want to trace and use it. Mmiotrace will only catch MMIO
>  accesses to areas that are ioremapped while mmiotrace is active.
>  
>  During tracing you can place comments (markers) into the trace by
> -$ echo "X is up" > /debug/tracing/trace_marker
> +$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
>  This makes it easier to see which part of the (huge) trace corresponds to
>  which action. It is recommended to place descriptive markers about what you
>  do.
>  
>  Shut down mmiotrace (requires root privileges):
> -$ echo nop > /debug/tracing/current_tracer
> +$ echo nop > /sys/kernel/debug/tracing/current_tracer
>  The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
>  pressing ctrl+c.
>  
> @@ -78,10 +78,10 @@ to view your kernel log and look for "mmiotrace has lost events" warning. If
>  events were lost, the trace is incomplete. You should enlarge the buffers and
>  try again. Buffers are enlarged by first seeing how large the current buffers
>  are:
> -$ cat /debug/tracing/buffer_size_kb
> +$ cat /sys/kernel/debug/tracing/buffer_size_kb
>  gives you a number. Approximately double this number and write it back, for
>  instance:
> -$ echo 128000 > /debug/tracing/buffer_size_kb
> +$ echo 128000 > /sys/kernel/debug/tracing/buffer_size_kb
>  Then start again from the top.
>  
>  If you are doing a trace for a driver project, e.g. Nouveau, you should also
> diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
> index dc7a8c3..9aa8932 100644
> --- a/drivers/block/pktcdvd.c
> +++ b/drivers/block/pktcdvd.c
> @@ -430,7 +430,7 @@ static void pkt_sysfs_cleanup(void)
>  /********************************************************************
>    entries in debugfs
>  
> -  /debugfs/pktcdvd[0-7]/
> +  /sys/kernel/debug/pktcdvd[0-7]/
>  			info
>  
>   *******************************************************************/
> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
> index c77c6c6..6ce0e26 100644
> --- a/drivers/gpu/drm/drm_debugfs.c
> +++ b/drivers/gpu/drm/drm_debugfs.c
> @@ -105,7 +105,7 @@ int drm_debugfs_create_files(struct drm_info_list *files, int count,
>  		ent = debugfs_create_file(files[i].name, S_IFREG | S_IRUGO,
>  					  root, tmp, &drm_debugfs_fops);
>  		if (!ent) {
> -			DRM_ERROR("Cannot create /debugfs/dri/%s/%s\n",
> +			DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s/%s\n",
>  				  name, files[i].name);
>  			drm_free(tmp, sizeof(struct drm_info_node),
>  				 _DRM_DRIVER);
> @@ -133,9 +133,9 @@ EXPORT_SYMBOL(drm_debugfs_create_files);
>   * \param minor device minor number
>   * \param root DRI debugfs dir entry.
>   *
> - * Create the DRI debugfs root entry "/debugfs/dri", the device debugfs root entry
> - * "/debugfs/dri/%minor%/", and each entry in debugfs_list as
> - * "/debugfs/dri/%minor%/%name%".
> + * Create the DRI debugfs root entry "/sys/kernel/debug/dri", the device debugfs root entry
> + * "/sys/kernel/debug/dri/%minor%/", and each entry in debugfs_list as
> + * "/sys/kernel/debug/dri/%minor%/%name%".
>   */
>  int drm_debugfs_init(struct drm_minor *minor, int minor_id,
>  		     struct dentry *root)
> @@ -148,7 +148,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
>  	sprintf(name, "%d", minor_id);
>  	minor->debugfs_root = debugfs_create_dir(name, root);
>  	if (!minor->debugfs_root) {
> -		DRM_ERROR("Cannot create /debugfs/dri/%s\n", name);
> +		DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s\n", name);
>  		return -1;
>  	}
>  
> @@ -165,7 +165,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
>  		ret = dev->driver->debugfs_init(minor);
>  		if (ret) {
>  			DRM_ERROR("DRM: Driver failed to initialize "
> -				  "/debugfs/dri.\n");
> +				  "/sys/kernel/debug/dri.\n");
>  			return ret;
>  		}
>  	}
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 019b7c5..1bf7efd 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -339,7 +339,7 @@ static int __init drm_core_init(void)
>  
>  	drm_debugfs_root = debugfs_create_dir("dri", NULL);
>  	if (!drm_debugfs_root) {
> -		DRM_ERROR("Cannot create /debugfs/dri\n");
> +		DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
>  		ret = -1;
>  		goto err_p3;
>  	}
> diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
> index b9631e3..b2a93c4 100644
> --- a/drivers/gpu/drm/drm_stub.c
> +++ b/drivers/gpu/drm/drm_stub.c
> @@ -328,7 +328,7 @@ static int drm_get_minor(struct drm_device *dev, struct drm_minor **minor, int t
>  #if defined(CONFIG_DEBUG_FS)
>  	ret = drm_debugfs_init(new_minor, minor_id, drm_debugfs_root);
>  	if (ret) {
> -		DRM_ERROR("DRM: Failed to initialize /debugfs/dri.\n");
> +		DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
>  		goto err_g2;
>  	}
>  #endif
> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> index 214a92d..a170cea 100644
> --- a/drivers/net/Kconfig
> +++ b/drivers/net/Kconfig
> @@ -2200,7 +2200,7 @@ config SKGE_DEBUG
>         depends on SKGE && DEBUG_FS
>         help
>  	 This option adds the ability to dump driver state for debugging.
> -	 The file debugfs/skge/ethX displays the state of the internal
> +	 The file /sys/kernel/debug/skge/ethX displays the state of the internal
>  	 transmit and receive rings.
>  
>  	 If unsure, say N.
> @@ -2226,7 +2226,7 @@ config SKY2_DEBUG
>         depends on SKY2 && DEBUG_FS
>         help
>  	 This option adds the ability to dump driver state for debugging.
> -	 The file debugfs/sky2/ethX displays the state of the internal
> +	 The file /sys/kernel/debug/sky2/ethX displays the state of the internal
>  	 transmit and receive rings.
>  
>  	 If unsure, say N.
> diff --git a/drivers/net/wimax/i2400m/i2400m.h b/drivers/net/wimax/i2400m/i2400m.h
> index 3ae2df3..da2e8f2 100644
> --- a/drivers/net/wimax/i2400m/i2400m.h
> +++ b/drivers/net/wimax/i2400m/i2400m.h
> @@ -389,7 +389,7 @@ struct i2400m {
>  	unsigned ready:1;		/* all probing steps done */
>  	unsigned rx_reorder:1;		/* RX reorder is enabled */
>  	u8 trace_msg_from_user;		/* echo rx msgs to 'trace' pipe */
> -					/* typed u8 so debugfs/u8 can tweak */
> +					/* typed u8 so /sys/kernel/debug/u8 can tweak */
>  	enum i2400m_system_state state;
>  	wait_queue_head_t state_wq;	/* Woken up when on state updates */
>  
> diff --git a/drivers/net/wireless/ath5k/Kconfig b/drivers/net/wireless/ath5k/Kconfig
> index 75383a5..fdfa708 100644
> --- a/drivers/net/wireless/ath5k/Kconfig
> +++ b/drivers/net/wireless/ath5k/Kconfig
> @@ -27,11 +27,11 @@ config ATH5K_DEBUG
>  	  Say Y, if and you will get debug options for ath5k.
>  	  To use this, you need to mount debugfs:
>  
> -	  mkdir /debug/
> -	  mount -t debugfs debug /debug/
> +	  mkdir /sys/kernel/debug/
> +	  mount -t debugfs debug /sys/kernel/debug/
>  
>  	  You will get access to files under:
> -	  /debug/ath5k/phy0/
> +	  /sys/kernel/debug/ath5k/phy0/
>  
>  	  To enable debug, pass the debug level to the debug module
>  	  parameter. For example:
> diff --git a/drivers/net/wireless/libertas/README b/drivers/net/wireless/libertas/README
> index d860fc3..ab6a2d5 100644
> --- a/drivers/net/wireless/libertas/README
> +++ b/drivers/net/wireless/libertas/README
> @@ -72,7 +72,7 @@ rdrf
>  	location that is to be read.  This parameter must be specified in
>  	hexadecimal (its possible to preceed preceding the number with a "0x").
>  
> -	Path: /debugfs/libertas_wireless/ethX/registers/
> +	Path: /sys/kernel/debug/libertas_wireless/ethX/registers/
>  
>  	Usage:
>  		echo "0xa123" > rdmac ; cat rdmac
> @@ -95,7 +95,7 @@ wrrf
>  sleepparams
>  	This command is used to set the sleepclock configurations
>  
> -	Path: /debugfs/libertas_wireless/ethX/
> +	Path: /sys/kernel/debug/libertas_wireless/ethX/
>  
>  	Usage:
>  		cat sleepparams: reads the current sleepclock configuration
> @@ -115,7 +115,7 @@ subscribed_events
>  	The subscribed_events directory contains the interface for the
>  	subscribed events API.
>  
> -	Path: /debugfs/libertas_wireless/ethX/subscribed_events/
> +	Path: /sys/kernel/debug/libertas_wireless/ethX/subscribed_events/
>  
>  	Each event is represented by a filename. Each filename consists of the
>  	following three fields:
> @@ -165,7 +165,7 @@ subscribed_events
>  extscan
>  	This command is used to do a specific scan.
>  
> -	Path: /debugfs/libertas_wireless/ethX/
> +	Path: /sys/kernel/debug/libertas_wireless/ethX/
>  
>  	Usage: echo "SSID" > extscan
>  
> @@ -179,7 +179,7 @@ getscantable
>  	Display the current contents of the driver scan table (ie. get the
>  	scan results).
>  
> -	Path: /debugfs/libertas_wireless/ethX/
> +	Path: /sys/kernel/debug/libertas_wireless/ethX/
>  
>  	Usage:
>  		cat getscantable
> @@ -188,7 +188,7 @@ setuserscan
>  	Initiate a customized scan and retrieve the results
>  
>  
> -	Path: /debugfs/libertas_wireless/ethX/
> +	Path: /sys/kernel/debug/libertas_wireless/ethX/
>  
>      Usage:
>         echo "[ARGS]" > setuserscan
> diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
> index 52be564..9112380 100644
> --- a/drivers/scsi/lpfc/lpfc_debugfs.c
> +++ b/drivers/scsi/lpfc/lpfc_debugfs.c
> @@ -51,8 +51,8 @@
>   * debugfs interface
>   *
>   * To access this interface the user should:
> - * # mkdir /debug
> - * # mount -t debugfs none /debug
> + * # mkdir /sys/kernel/debug
> + * # mount -t debugfs none /sys/kernel/debug
>   *
>   * The lpfc debugfs directory hierarchy is:
>   * lpfc/lpfcX/vportY
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index 883cd44..99b7aad 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -406,7 +406,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
>   *
>   * Use tracing_on/tracing_off when you want to quickly turn on or off
>   * tracing. It simply enables or disables the recording of the trace events.
> - * This also corresponds to the user space debugfs/tracing/tracing_on
> + * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
>   * file, which gives a means for the kernel and userspace to interact.
>   * Place a tracing_off() in the kernel where you want tracing to end.
>   * From user space, examine the trace, and then echo 1 > tracing_on
> diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
> index d35a7ee..9c9ac7d 100644
> --- a/include/linux/tracepoint.h
> +++ b/include/linux/tracepoint.h
> @@ -197,7 +197,7 @@ static inline void tracepoint_synchronize_unregister(void)
>   *	* This is how the trace record is structured and will
>   *	* be saved into the ring buffer. These are the fields
>   *	* that will be exposed to user-space in
> - *	* /debug/tracing/events/<*>/format.
> + *	* /sys/kernel/debug/tracing/events/<*>/format.
>   *	*
>   *	* The declared 'local variable' is called '__entry'
>   *	*
> @@ -257,7 +257,7 @@ static inline void tracepoint_synchronize_unregister(void)
>   * tracepoint callback (this is used by programmatic plugins and
>   * can also by used by generic instrumentation like SystemTap), and
>   * it is also used to expose a structured trace record in
> - * /debug/tracing/events/.
> + * /sys/kernel/debug/tracing/events/.
>   */
>  
>  #define TRACE_EVENT(name, proto, args, struct, assign, print)	\
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index 417d198..e5ce28f 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -120,7 +120,7 @@ config IRQSOFF_TRACER
>  	  disabled by default and can be runtime (re-)started
>  	  via:
>  
> -	      echo 0 > /debugfs/tracing/tracing_max_latency
> +	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
>  
>  	  (Note that kernel size and overhead increases with this option
>  	  enabled. This option and the preempt-off timing option can be
> @@ -141,7 +141,7 @@ config PREEMPT_TRACER
>  	  disabled by default and can be runtime (re-)started
>  	  via:
>  
> -	      echo 0 > /debugfs/tracing/tracing_max_latency
> +	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
>  
>  	  (Note that kernel size and overhead increases with this option
>  	  enabled. This option and the irqs-off timing option can be
> @@ -213,7 +213,7 @@ config TRACE_BRANCH_PROFILING
>  	  This tracer profiles all the the likely and unlikely macros
>  	  in the kernel. It will display the results in:
>  
> -	  /debugfs/tracing/profile_annotated_branch
> +	  /sys/kernel/debug/tracing/profile_annotated_branch
>  
>  	  Note: this will add a significant overhead, only turn this
>  	  on if you need to profile the system's use of these macros.
> @@ -228,7 +228,7 @@ config PROFILE_ALL_BRANCHES
>  	  taken in the kernel is recorded whether it hit or miss.
>  	  The results will be displayed in:
>  
> -	  /debugfs/tracing/profile_branch
> +	  /sys/kernel/debug/tracing/profile_branch
>  
>  	  This configuration, when enabled, will impose a great overhead
>  	  on the system. This should only be enabled when the system
> @@ -276,7 +276,7 @@ config STACK_TRACER
>  	select KALLSYMS
>  	help
>  	  This special tracer records the maximum stack footprint of the
> -	  kernel and displays it in debugfs/tracing/stack_trace.
> +	  kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
>  
>  	  This tracer works by hooking into every function call that the
>  	  kernel executes, and keeping a maximum stack depth value and
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index cda81ec..9b94d57 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -335,7 +335,7 @@ static raw_spinlock_t ftrace_max_lock =
>  /*
>   * Copy the new maximum trace into the separate maximum-trace
>   * structure. (this way the maximum trace is permanently saved,
> - * for later retrieval via /debugfs/tracing/latency_trace)
> + * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
>   */
>  static void
>  __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
> @@ -2366,21 +2366,21 @@ static const struct file_operations tracing_iter_fops = {
>  
>  static const char readme_msg[] =
>  	"tracing mini-HOWTO:\n\n"
> -	"# mkdir /debug\n"
> -	"# mount -t debugfs nodev /debug\n\n"
> -	"# cat /debug/tracing/available_tracers\n"
> +	"# mkdir /sys/kernel/debug\n"
> +	"# mount -t debugfs nodev /sys/kernel/debug\n\n"
> +	"# cat /sys/kernel/debug/tracing/available_tracers\n"
>  	"wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
> -	"# cat /debug/tracing/current_tracer\n"
> +	"# cat /sys/kernel/debug/tracing/current_tracer\n"
>  	"nop\n"
> -	"# echo sched_switch > /debug/tracing/current_tracer\n"
> -	"# cat /debug/tracing/current_tracer\n"
> +	"# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
> +	"# cat /sys/kernel/debug/tracing/current_tracer\n"
>  	"sched_switch\n"
> -	"# cat /debug/tracing/trace_options\n"
> +	"# cat /sys/kernel/debug/tracing/trace_options\n"
>  	"noprint-parent nosym-offset nosym-addr noverbose\n"
> -	"# echo print-parent > /debug/tracing/trace_options\n"
> -	"# echo 1 > /debug/tracing/tracing_enabled\n"
> -	"# cat /debug/tracing/trace > /tmp/trace.txt\n"
> -	"# echo 0 > /debug/tracing/tracing_enabled\n"
> +	"# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
> +	"# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
> +	"# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
> +	"# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
>  ;
>  
>  static ssize_t
> diff --git a/scripts/tracing/draw_functrace.py b/scripts/tracing/draw_functrace.py
> index 902f9a9..66f4d1b 100644
> --- a/scripts/tracing/draw_functrace.py
> +++ b/scripts/tracing/draw_functrace.py
> @@ -12,10 +12,10 @@ calls. Only the functions's names and the the call time are provided.
>  
>  Usage:
>  	Be sure that you have CONFIG_FUNCTION_TRACER
> -	# mkdir /debugfs
> -	# mount -t debug debug /debug
> -	# echo function > /debug/tracing/current_tracer
> -	$ cat /debug/tracing/trace_pipe > ~/raw_trace_func
> +	# mkdir /sys/kernel/debug
> +	# mount -t debug debug /sys/kernel/debug
> +	# echo function > /sys/kernel/debug/tracing/current_tracer
> +	$ cat /sys/kernel/debug/tracing/trace_pipe > ~/raw_trace_func
>  	Wait some times but not too much, the script is a bit slow.
>  	Break the pipe (Ctrl + Z)
>  	$ scripts/draw_functrace.py < raw_trace_func > draw_functrace
> -- 
> 1.6.3.1
> 
>  
> -----------------------------------------------
> To unsubscribe from this list: send the line "unsubscribe linux-***" 
> in the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 
> GeunSik Lim (  S A M S U N G     E L E C T R O N I C S  )
> e-Mail  :1) geunsik.lim@samsung.com
>          2) leemgs@gmail.com , leemgs1@gmail.com
> HomePage: http://blog.naver.com/invain/
> -----------------------------------------------
> 
> 

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Fri, 29 May 2009, Steven Rostedt wrote:
> ===
> When debugfs is configured into the kernel (which selecting any ftrace 
> option will do) the directory /sys/kernel/debug will be created. To mount 
> this directory, you can add to your /etc/fstab file:
> 
>   debugfs	/debug		debugfs	defaults	0	0

s,/debug,/sys/kernel/debug,

> 
> Or you can mount it at run time with:
> 
>   mount -t debugfs nodev /sys/kernel/debug
> 
> For quicker access to that directory you may want to make a soft link to 
> it:
> 
>  ln -s /sys/kernel/debug /debug
> 
> Any selected ftrace option will also create a directory called tracing 
> within the debugfs. The rest of the document will assume that you are in 
> the ftrace directory (cd /sys/kernel/debugfs) and will only concentrate
> on the files within that directory and not distract from the content with 
> the extended "/sys/kernel/debug/tracing" path name.
> ===

-- Steve

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Fri, 29 May 2009, Steven Rostedt wrote:
> ===
> When debugfs is configured into the kernel (which selecting any ftrace 
> option will do) the directory /sys/kernel/debug will be created. To mount 
> this directory, you can add to your /etc/fstab file:
> 
>   debugfs	/debug		debugfs	defaults	0	0
> 
> Or you can mount it at run time with:
> 
>   mount -t debugfs nodev /sys/kernel/debug
> 
> For quicker access to that directory you may want to make a soft link to 
> it:
> 
>  ln -s /sys/kernel/debug /debug
> 
> Any selected ftrace option will also create a directory called tracing 
> within the debugfs. The rest of the document will assume that you are in 
> the ftrace directory (cd /sys/kernel/debugfs) and will only concentrate

s,/sys/kernel/debugfs,/sys/kernel/debug/tracing,

> on the files within that directory and not distract from the content with 
> the extended "/sys/kernel/debug/tracing" path name.
> ===

-- Steve

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Sat, 30 May 2009, GeunSik Lim wrote:

> 
> 
> Dear Greg and Steen,
> 
> Thanks your advices and opinions about a confusion according to  
> too many mount directory names for debugfs. I made rfc v2 patch file again like belows.
> Can I hear your advices about below patch contents?.  
> 
> * ref: 
> http://groups.google.com/group/linux.kernel/browse_thread/thread/c34e386587979340/dc52317f888e78b6?#dc52317f888e78b6
> 
> 
> Regards,
> GeunSik Lim.
> 
> Subject: [PATCH]   Fix terminology inconsistency of dir name to mount debugfs filesystem.
> 
>       Many developers use "/debug/" or "/debugfs/ directory name to mount
>       debugfs filesystem for ftrace according to
>       ./Documentation/tracers/ftrace.txt file.
> 
>       And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
>       existed in kernel source like ftrace, DRM, Wireless, Network[sky2]files
>       to mount debugfs filesystem.
> 
>       debugfs means debug filesystem for debugging easy to use by greg kroah
>       hartman. "/sys/kernel/debug/" name is suitable as directory name
>       of debugfs filesystem.
>       -debugfs related reference: http://lwn.net/Articles/115405/

Note, LWN has an update this week:

 http://lwn.net/Articles/334546/

But it currently is subscriber only. Others would need to either buy a 
subscription (plug) or wait a week for it to become open.

Still for some aspects, just having "debugfs" without the leading "/" 
might just be self explanatory. We can assume the user already knows where 
debugfs is mounted.

-- Steve


> 
>       Fix inconsistency of directory name to mount debugfs filesystem.
> 
>          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
>          Acked-By: Inaky Perez-Gonzalez <inaky@linux.intel.com>
>          CC: Greg KH <greg@kroah.com>
>          CC: Steven Rostedt <rostedt@goodmis.org>
>          CC: linux-kernel <linux-kernel@vger.kernel.org>

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

Thanks your advice. I agree with your reply about this patch.
I updated contents that you advised like belows.
If I mistake, Please correct me.

And, I also need your review  about below 2 contents in the ftrace.txt file.

Thanks,
GeunSik Lim.


1)
@@ -1146,7 +1158,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1154,26 +1166,23 @@ int main(int argc, char *argv[]) {
 	[...]
 }


@@ -1217,12 +1226,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;

-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd =
open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);

-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid",
O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);
-Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
-/sys/kernel/debug). For simple one time traces, the above is
-sufficent. For anything else, a search through /proc/mounts may
+Note: Here we hard coded the path name. A search through /proc/mounts may
 be needed to find where the debugfs file-system is mounted.

2)
More details can be found in the source code, in the
-kernel/tracing/*.c files.
+kernel/trace/*.c files



* about ftrace.txt file
---
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..790199b 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
                (dual licensed under the GPL v2)
 Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
 	     John Kacur, and David Teigland.
-
 Written for: 2.6.28-rc2

 Introduction
@@ -33,13 +32,26 @@ The File System
 Ftrace uses the debugfs file system to hold the control files as
 well as the files to display output.

-To mount the debugfs system:
+When debugfs is configured into the kernel (which selecting any ftrace
+option will do) the directory /sys/kernel/debug will be created. To mount
+this directory, you can add to your /etc/fstab file:
+
+ debugfs       /sys/kernel/debug          debugfs defaults        0       0
+
+Or you can mount it at run time with:
+
+ mount -t debugfs nodev /sys/kernel/debug
+
+For quicker access to that directory you may want to make a soft link to
+it:

-  # mkdir /debug
-  # mount -t debugfs nodev /debug
+ ln -s /sys/kernel/debug /debug

-( Note: it is more common to mount at /sys/kernel/debug, but for
-  simplicity this document will use /debug)
+Any selected ftrace option will also create a directory called tracing
+within the debugfs. The rest of the document will assume that you are in
+the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
+on the files within that directory and not distract from the content with
+the extended "/sys/kernel/debug/tracing" path name.

 That's it! (assuming that you have ftrace configured into your kernel)

@@ -389,18 +401,18 @@ trace_options
 The trace_options file is used to control what gets printed in
 the trace output. To see what is available, simply cat the file:

-  cat /debug/tracing/trace_options
+  cat ./trace_options
   print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
   noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj

 To disable one of the options, echo in the option prepended with
 "no".

-  echo noprint-parent > /debug/tracing/trace_options
+  echo noprint-parent > ./trace_options

 To enable an option, leave off the "no".

-  echo sym-offset > /debug/tracing/trace_options
+  echo sym-offset > ./trace_options

 Here are the available options:

@@ -476,11 +488,11 @@ sched_switch
 This tracer simply records schedule switches. Here is an example
 of how to use it.

- # echo sched_switch > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo sched_switch > ./current_tracer
+ # echo 1 > ./tracing_enabled
  # sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > ./tracing_enabled
+ # cat ./trace

 # tracer: sched_switch
 #
@@ -574,13 +586,13 @@ new trace is saved.
 To reset the maximum, echo 0 into tracing_max_latency. Here is
 an example:

- # echo irqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo irqsoff > ./current_tracer
+ # echo 0 > ./tracing_max_latency
+ # echo 1 > ./tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > ./tracing_enabled
+ # cat ./latency_trace
 # tracer: irqsoff
 #
 irqsoff latency trace v1.1.5 on 2.6.26
@@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum
latency for
 which preemption was disabled. The control of preemptoff tracer
 is much like the irqsoff tracer.

- # echo preemptoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptoff > ./current_tracer
+ # echo 0 > ./tracing_max_latency
+ # echo 1 > ./tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > ./tracing_enabled
+ # cat ./latency_trace
 # tracer: preemptoff
 #
 preemptoff latency trace v1.1.5 on 2.6.26-rc8
@@ -828,13 +840,13 @@ tracer.
 Again, using this trace is much like the irqsoff and preemptoff
 tracers.

- # echo preemptirqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptirqsoff > ./current_tracer
+ # echo 0 > ./tracing_max_latency
+ # echo 1 > ./tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > ./tracing_enabled
+ # cat ./latency_trace
 # tracer: preemptirqsoff
 #
 preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
@@ -990,12 +1002,12 @@ slightly differently than we did with the
previous tracers.
 Instead of performing an 'ls', we will run 'sleep 1' under
 'chrt' which changes the priority of the task.

- # echo wakeup > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo wakeup > ./current_tracer
+ # echo 0 > ./tracing_max_latency
+ # echo 1 > ./tracing_enabled
  # chrt -f 5 sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > ./tracing_enabled
+ # cat ./latency_trace
 # tracer: wakeup
 #
 wakeup latency trace v1.1.5 on 2.6.26-rc8
@@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
 ftrace_enabled is set; otherwise this tracer is a nop.

  # sysctl kernel.ftrace_enabled=1
- # echo function > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo function > ./current_tracer
+ # echo 1 > ./tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > ./tracing_enabled
+ # cat ./trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1146,7 +1158,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1154,26 +1166,23 @@ int main(int argc, char *argv[]) {
 	[...]
 }

-Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
-/sys/kernel/debug). For simple one time traces, the above is
-sufficent. For anything else, a search through /proc/mounts may
+Note: Here we hard coded the path name. A search through /proc/mounts may
 be needed to find where the debugfs file-system is mounted.


 Single thread tracing
 ---------------------

-By writing into /debug/tracing/set_ftrace_pid you can trace a
+By writing into ./set_ftrace_pid you can trace a
 single thread. For example:

-# cat /debug/tracing/set_ftrace_pid
+# cat ./set_ftrace_pid
 no pid
-# echo 3111 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/set_ftrace_pid
+# echo 3111 > ./set_ftrace_pid
+# cat ./set_ftrace_pid
 3111
-# echo function > /debug/tracing/current_tracer
-# cat /debug/tracing/trace | head
+# echo function > ./current_tracer
+# cat ./trace | head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1184,8 +1193,8 @@ no pid
      yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base
<-hrtimer_try_to_cancel
      yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
      yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
-# echo -1 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/trace |head
+# echo -1 > ./set_ftrace_pid
+# cat ./trace |head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1217,12 +1226,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;

-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd =
open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);

-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid",
O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);

@@ -1374,22 +1383,22 @@ want, depending on your needs.
   tracing_cpu_mask file) or you might sometimes see unordered
   function calls while cpu tracing switch.

-	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
-	show: echo funcgraph-cpu > /debug/tracing/trace_options
+	hide: echo nofuncgraph-cpu > ./trace_options
+	show: echo funcgraph-cpu > ./trace_options

 - The duration (function's time of execution) is displayed on
   the closing bracket line of a function or on the same line
   than the current function in case of a leaf one. It is default
   enabled.

-	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
-	show: echo funcgraph-duration > /debug/tracing/trace_options
+	hide: echo nofuncgraph-duration > ./trace_options
+	show: echo funcgraph-duration > ./trace_options

 - The overhead field precedes the duration field in case of
   reached duration thresholds.

-	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
-	show: echo funcgraph-overhead > /debug/tracing/trace_options
+	hide: echo nofuncgraph-overhead > ./trace_options
+	show: echo funcgraph-overhead > ./trace_options
 	depends on: funcgraph-duration

   ie:
@@ -1418,8 +1427,8 @@ want, depending on your needs.
 - The task/pid field displays the thread cmdline and pid which
   executed the function. It is default disabled.

-	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
-	show: echo funcgraph-proc > /debug/tracing/trace_options
+	hide: echo nofuncgraph-proc > ./trace_options
+	show: echo funcgraph-proc > ./trace_options

   ie:

@@ -1442,8 +1451,8 @@ want, depending on your needs.
   system clock since it started. A snapshot of this time is
   given on each entry/exit of functions

-	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
-	show: echo funcgraph-abstime > /debug/tracing/trace_options
+	hide: echo nofuncgraph-abstime > ./trace_options
+	show: echo funcgraph-abstime > ./trace_options

   ie:

@@ -1540,7 +1549,7 @@ listed in:

    available_filter_functions

- # cat /debug/tracing/available_filter_functions
+ # cat ./available_filter_functions
 put_prev_task_idle
 kmem_cache_create
 pick_next_task_rt
@@ -1552,12 +1561,12 @@ mutex_lock
 If I am only interested in sys_nanosleep and hrtimer_interrupt:

  # echo sys_nanosleep hrtimer_interrupt \
-		> /debug/tracing/set_ftrace_filter
- # echo ftrace > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+		> ./set_ftrace_filter
+ # echo ftrace > ./current_tracer
+ # echo 1 > ./tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > ./tracing_enabled
+ # cat ./trace
 # tracer: ftrace
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1568,7 +1577,7 @@ If I am only interested in sys_nanosleep and
hrtimer_interrupt:

 To see which functions are being traced, you can cat the file:

- # cat /debug/tracing/set_ftrace_filter
+ # cat ./set_ftrace_filter
 hrtimer_interrupt
 sys_nanosleep

@@ -1588,7 +1597,7 @@ Note: It is better to use quotes to enclose the
wild cards,
       otherwise the shell may expand the parameters into names
       of files in the local directory.

- # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' > ./set_ftrace_filter

 Produces:

@@ -1609,7 +1618,7 @@ Produces:

 Notice that we lost the sys_nanosleep.

- # cat /debug/tracing/set_ftrace_filter
+ # cat ./set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1635,17 +1644,17 @@ To append to the filters, use '>>'
 To clear out a filter so that all functions will be recorded
 again:

- # echo > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo > ./set_ftrace_filter
+ # cat ./set_ftrace_filter
  #

 Again, now we want to append.

- # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo sys_nanosleep > ./set_ftrace_filter
+ # cat ./set_ftrace_filter
 sys_nanosleep
- # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' >> ./set_ftrace_filter
+ # cat ./set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1668,7 +1677,7 @@ hrtimer_init_sleeper
 The set_ftrace_notrace prevents those functions from being
 traced.

- # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+ # echo '*preempt*' '*lock*' > ./set_ftrace_notrace

 Produces:

@@ -1758,13 +1767,13 @@ the effect on the tracing is different. Every read from
 trace_pipe is consumed. This means that subsequent reads will be
 different. The trace is live.

- # echo function > /debug/tracing/current_tracer
- # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+ # echo function > ./current_tracer
+ # cat ./trace_pipe > /tmp/trace.out &
 [1] 4153
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo 1 > ./tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > ./tracing_enabled
+ # cat ./trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1800,7 +1809,7 @@ number listed is the number of entries that can
be recorded per
 CPU. To know the full size, multiply the number of possible CPUS
 with the number of entries.

- # cat /debug/tracing/buffer_size_kb
+ # cat ./buffer_size_kb
 1408 (units kilobytes)

 Note, to modify this, you must have tracing completely disabled.
@@ -1808,21 +1817,21 @@ To do that, echo "nop" into the current_tracer. If the
 current_tracer is not set to "nop", an EINVAL error will be
 returned.

- # echo nop > /debug/tracing/current_tracer
- # echo 10000 > /debug/tracing/buffer_size_kb
- # cat /debug/tracing/buffer_size_kb
+ # echo nop > ./current_tracer
+ # echo 10000 > ./buffer_size_kb
+ # cat ./buffer_size_kb
 10000 (units kilobytes)

 The number of pages which will be allocated is limited to a
 percentage of available memory. Allocating too much will produce
 an error.

- # echo 1000000000000 > /debug/tracing/buffer_size_kb
+ # echo 1000000000000 > ./buffer_size_kb
 -bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/buffer_size_kb
+ # cat ./buffer_size_kb
 85

 ---

On Sat, May 30, 2009 at 1:48 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
>
>
>
> On Sat, 30 May 2009, GeunSik Lim wrote:
>
>>
>>
>> Dear Greg and Steen,
>>
>> Thanks your advices and opinions about a confusion according to
>> too many mount directory names for debugfs. I made rfc v2 patch file again like belows.
>> Can I hear your advices about below patch contents?.
>>
>> * ref:
>> http://groups.google.com/group/linux.kernel/browse_thread/thread/c34e386587979340/dc52317f888e78b6?#dc52317f888e78b6
>>
>>
>> Regards,
>> GeunSik Lim.
>>
>> Subject: [PATCH]   Fix terminology inconsistency of dir name to mount debugfs filesystem.
>>
>>       Many developers use "/debug/" or "/debugfs/ directory name to mount
>>       debugfs filesystem for ftrace according to
>>       ./Documentation/tracers/ftrace.txt file.
>>
>>       And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
>>       existed in kernel source like ftrace, DRM, Wireless, Network[sky2]files
>>       to mount debugfs filesystem.
>>
>>       debugfs means debug filesystem for debugging easy to use by greg kroah
>>       hartman. "/sys/kernel/debug/" name is suitable as directory name
>>       of debugfs filesystem.
>>       -debugfs related reference: http://lwn.net/Articles/115405/
>
> Note, LWN has an update this week:
>
>  http://lwn.net/Articles/334546/
>
> But it currently is subscriber only. Others would need to either buy a
> subscription (plug) or wait a week for it to become open.
>
> Still for some aspects, just having "debugfs" without the leading "/"
> might just be self explanatory. We can assume the user already knows where
> debugfs is mounted.
>
> -- Steve
>
>
>>
>>       Fix inconsistency of directory name to mount debugfs filesystem.
>>
>>          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
>>          Acked-By: Inaky Perez-Gonzalez <inaky@linux.intel.com>
>>          CC: Greg KH <greg@kroah.com>
>>          CC: Steven Rostedt <rostedt@goodmis.org>
>>          CC: linux-kernel <linux-kernel@vger.kernel.org>
>



-- 
Regards,
GeunSik Lim ( SAMSUNG ELECTRONICS)
Blog : http://blog.naver.com/invain/
e-Mail: geunsik.lim@samsung.com
           leemgs@gmail.com , leemgs1@gmail.com
--
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Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 21851 bytes --]


On Sat, 30 May 2009, GeunSik Lim wrote:

> Thanks your advice. I agree with your reply about this patch.
> I updated contents that you advised like belows.
> If I mistake, Please correct me.
> 
> And, I also need your review  about below 2 contents in the ftrace.txt file.
> 
> Thanks,
> GeunSik Lim.
> 
> 
> 1)
> @@ -1146,7 +1158,7 @@ int trace_fd;
>  [...]
>  int main(int argc, char *argv[]) {
>  	[...]
> -	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
> +	trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
>  	[...]
>  	if (condition_hit()) {
>  		write(trace_fd, "0", 1);
> @@ -1154,26 +1166,23 @@ int main(int argc, char *argv[]) {
>  	[...]
>  }
> 
> 
> @@ -1217,12 +1226,12 @@ int main (int argc, char **argv)
>                  char line[64];
>                  int s;
> 
> -                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
> +                ffd =
> open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
>                  if (ffd < 0)
>                          exit(-1);
>                  write(ffd, "nop", 3);
> 
> -                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
> +                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid",
> O_WRONLY);
>                  s = sprintf(line, "%d\n", getpid());
>                  write(fd, line, s);
> -Note: Here we hard coded the path name. The debugfs mount is not
> -guaranteed to be at /debug (and is more commonly at
> -/sys/kernel/debug). For simple one time traces, the above is
> -sufficent. For anything else, a search through /proc/mounts may
> +Note: Here we hard coded the path name. A search through /proc/mounts may
>  be needed to find where the debugfs file-system is mounted.

Here's the function I use:

#define _STR(x) x
#define STR(x) _STR(x)
#define MAX_PATH 256

const char *find_debugfs(void)
{
	static char debugfs[MAX_PATH+1];
	static int debugfs_found;
	char type[100];
	FILE *fp;

	if (debugfs_found)
		return debugfs;


	if ((fp = fopen("/proc/mounts","r")) == NULL) {
		perror("/proc/mounts");
		return NULL;
	}

	while (fscanf(fp, "%*s %"
		      STR(MAX_PATH)
		      "s %99s %*s %*d %*d\n",
		      debugfs, type) == 2) {
		if (strcmp(type, "debugfs") == 0)
			break;
	}
	fclose(fp);

	if (strcmp(type, "debugfs") != 0) {
		fprintf(stderr, "debugfs not mounted");
		return NULL;
	}

	debugfs_found = 1;

	return debugfs;
}

This might be a good idea to show it. This is the most robust since it 
does not hard code the debugfs directory.

> 
> 2)
> More details can be found in the source code, in the
> -kernel/tracing/*.c files.
> +kernel/trace/*.c files
> 
> 
> 
> * about ftrace.txt file
> ---
> diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
> index fd9a3e6..790199b 100644
> --- a/Documentation/trace/ftrace.txt
> +++ b/Documentation/trace/ftrace.txt
> @@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
>                 (dual licensed under the GPL v2)
>  Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
>  	     John Kacur, and David Teigland.
> -
>  Written for: 2.6.28-rc2
> 
>  Introduction
> @@ -33,13 +32,26 @@ The File System
>  Ftrace uses the debugfs file system to hold the control files as
>  well as the files to display output.
> 
> -To mount the debugfs system:
> +When debugfs is configured into the kernel (which selecting any ftrace
> +option will do) the directory /sys/kernel/debug will be created. To mount
> +this directory, you can add to your /etc/fstab file:
> +
> + debugfs       /sys/kernel/debug          debugfs defaults        0       0
> +
> +Or you can mount it at run time with:
> +
> + mount -t debugfs nodev /sys/kernel/debug
> +
> +For quicker access to that directory you may want to make a soft link to
> +it:
> 
> -  # mkdir /debug
> -  # mount -t debugfs nodev /debug
> + ln -s /sys/kernel/debug /debug
> 
> -( Note: it is more common to mount at /sys/kernel/debug, but for
> -  simplicity this document will use /debug)
> +Any selected ftrace option will also create a directory called tracing
> +within the debugfs. The rest of the document will assume that you are in
> +the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
> +on the files within that directory and not distract from the content with
> +the extended "/sys/kernel/debug/tracing" path name.
> 
>  That's it! (assuming that you have ftrace configured into your kernel)
> 
> @@ -389,18 +401,18 @@ trace_options
>  The trace_options file is used to control what gets printed in
>  the trace output. To see what is available, simply cat the file:
> 
> -  cat /debug/tracing/trace_options
> +  cat ./trace_options

Please remove the "./", it is also distracting. We state that we "cd" to 
the location. "cat trace_options" is good enough.

Same for the all the others below.

Also, since I'm the most picky about this, you may want to remove the 
ftrace files from the patch and move it to another patch. That way the 
owners of the other files can ack them and get those changes in. When we 
have something for ftrace, I'll give my ack. But lets not hold up the 
other changes because of me ;-)

-- Steve

>    print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
>    noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj
> 
>  To disable one of the options, echo in the option prepended with
>  "no".
> 
> -  echo noprint-parent > /debug/tracing/trace_options
> +  echo noprint-parent > ./trace_options
> 
>  To enable an option, leave off the "no".
> 
> -  echo sym-offset > /debug/tracing/trace_options
> +  echo sym-offset > ./trace_options
> 
>  Here are the available options:
> 
> @@ -476,11 +488,11 @@ sched_switch
>  This tracer simply records schedule switches. Here is an example
>  of how to use it.
> 
> - # echo sched_switch > /debug/tracing/current_tracer
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo sched_switch > ./current_tracer
> + # echo 1 > ./tracing_enabled
>   # sleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > ./tracing_enabled
> + # cat ./trace
> 
>  # tracer: sched_switch
>  #
> @@ -574,13 +586,13 @@ new trace is saved.
>  To reset the maximum, echo 0 into tracing_max_latency. Here is
>  an example:
> 
> - # echo irqsoff > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo irqsoff > ./current_tracer
> + # echo 0 > ./tracing_max_latency
> + # echo 1 > ./tracing_enabled
>   # ls -ltr
>   [...]
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > ./tracing_enabled
> + # cat ./latency_trace
>  # tracer: irqsoff
>  #
>  irqsoff latency trace v1.1.5 on 2.6.26
> @@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum
> latency for
>  which preemption was disabled. The control of preemptoff tracer
>  is much like the irqsoff tracer.
> 
> - # echo preemptoff > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo preemptoff > ./current_tracer
> + # echo 0 > ./tracing_max_latency
> + # echo 1 > ./tracing_enabled
>   # ls -ltr
>   [...]
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > ./tracing_enabled
> + # cat ./latency_trace
>  # tracer: preemptoff
>  #
>  preemptoff latency trace v1.1.5 on 2.6.26-rc8
> @@ -828,13 +840,13 @@ tracer.
>  Again, using this trace is much like the irqsoff and preemptoff
>  tracers.
> 
> - # echo preemptirqsoff > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo preemptirqsoff > ./current_tracer
> + # echo 0 > ./tracing_max_latency
> + # echo 1 > ./tracing_enabled
>   # ls -ltr
>   [...]
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > ./tracing_enabled
> + # cat ./latency_trace
>  # tracer: preemptirqsoff
>  #
>  preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
> @@ -990,12 +1002,12 @@ slightly differently than we did with the
> previous tracers.
>  Instead of performing an 'ls', we will run 'sleep 1' under
>  'chrt' which changes the priority of the task.
> 
> - # echo wakeup > /debug/tracing/current_tracer
> - # echo 0 > /debug/tracing/tracing_max_latency
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo wakeup > ./current_tracer
> + # echo 0 > ./tracing_max_latency
> + # echo 1 > ./tracing_enabled
>   # chrt -f 5 sleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/latency_trace
> + # echo 0 > ./tracing_enabled
> + # cat ./latency_trace
>  # tracer: wakeup
>  #
>  wakeup latency trace v1.1.5 on 2.6.26-rc8
> @@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
>  ftrace_enabled is set; otherwise this tracer is a nop.
> 
>   # sysctl kernel.ftrace_enabled=1
> - # echo function > /debug/tracing/current_tracer
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo function > ./current_tracer
> + # echo 1 > ./tracing_enabled
>   # usleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > ./tracing_enabled
> + # cat ./trace
>  # tracer: function
>  #
>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
> @@ -1146,7 +1158,7 @@ int trace_fd;
>  [...]
>  int main(int argc, char *argv[]) {
>  	[...]
> -	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
> +	trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
>  	[...]
>  	if (condition_hit()) {
>  		write(trace_fd, "0", 1);
> @@ -1154,26 +1166,23 @@ int main(int argc, char *argv[]) {
>  	[...]
>  }
> 
> -Note: Here we hard coded the path name. The debugfs mount is not
> -guaranteed to be at /debug (and is more commonly at
> -/sys/kernel/debug). For simple one time traces, the above is
> -sufficent. For anything else, a search through /proc/mounts may
> +Note: Here we hard coded the path name. A search through /proc/mounts may
>  be needed to find where the debugfs file-system is mounted.
> 
> 
>  Single thread tracing
>  ---------------------
> 
> -By writing into /debug/tracing/set_ftrace_pid you can trace a
> +By writing into ./set_ftrace_pid you can trace a
>  single thread. For example:
> 
> -# cat /debug/tracing/set_ftrace_pid
> +# cat ./set_ftrace_pid
>  no pid
> -# echo 3111 > /debug/tracing/set_ftrace_pid
> -# cat /debug/tracing/set_ftrace_pid
> +# echo 3111 > ./set_ftrace_pid
> +# cat ./set_ftrace_pid
>  3111
> -# echo function > /debug/tracing/current_tracer
> -# cat /debug/tracing/trace | head
> +# echo function > ./current_tracer
> +# cat ./trace | head
>   # tracer: function
>   #
>   #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
> @@ -1184,8 +1193,8 @@ no pid
>       yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base
> <-hrtimer_try_to_cancel
>       yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
>       yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
> -# echo -1 > /debug/tracing/set_ftrace_pid
> -# cat /debug/tracing/trace |head
> +# echo -1 > ./set_ftrace_pid
> +# cat ./trace |head
>   # tracer: function
>   #
>   #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
> @@ -1217,12 +1226,12 @@ int main (int argc, char **argv)
>                  char line[64];
>                  int s;
> 
> -                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
> +                ffd =
> open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
>                  if (ffd < 0)
>                          exit(-1);
>                  write(ffd, "nop", 3);
> 
> -                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
> +                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid",
> O_WRONLY);
>                  s = sprintf(line, "%d\n", getpid());
>                  write(fd, line, s);
> 
> @@ -1374,22 +1383,22 @@ want, depending on your needs.
>    tracing_cpu_mask file) or you might sometimes see unordered
>    function calls while cpu tracing switch.
> 
> -	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
> -	show: echo funcgraph-cpu > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-cpu > ./trace_options
> +	show: echo funcgraph-cpu > ./trace_options
> 
>  - The duration (function's time of execution) is displayed on
>    the closing bracket line of a function or on the same line
>    than the current function in case of a leaf one. It is default
>    enabled.
> 
> -	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
> -	show: echo funcgraph-duration > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-duration > ./trace_options
> +	show: echo funcgraph-duration > ./trace_options
> 
>  - The overhead field precedes the duration field in case of
>    reached duration thresholds.
> 
> -	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
> -	show: echo funcgraph-overhead > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-overhead > ./trace_options
> +	show: echo funcgraph-overhead > ./trace_options
>  	depends on: funcgraph-duration
> 
>    ie:
> @@ -1418,8 +1427,8 @@ want, depending on your needs.
>  - The task/pid field displays the thread cmdline and pid which
>    executed the function. It is default disabled.
> 
> -	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
> -	show: echo funcgraph-proc > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-proc > ./trace_options
> +	show: echo funcgraph-proc > ./trace_options
> 
>    ie:
> 
> @@ -1442,8 +1451,8 @@ want, depending on your needs.
>    system clock since it started. A snapshot of this time is
>    given on each entry/exit of functions
> 
> -	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
> -	show: echo funcgraph-abstime > /debug/tracing/trace_options
> +	hide: echo nofuncgraph-abstime > ./trace_options
> +	show: echo funcgraph-abstime > ./trace_options
> 
>    ie:
> 
> @@ -1540,7 +1549,7 @@ listed in:
> 
>     available_filter_functions
> 
> - # cat /debug/tracing/available_filter_functions
> + # cat ./available_filter_functions
>  put_prev_task_idle
>  kmem_cache_create
>  pick_next_task_rt
> @@ -1552,12 +1561,12 @@ mutex_lock
>  If I am only interested in sys_nanosleep and hrtimer_interrupt:
> 
>   # echo sys_nanosleep hrtimer_interrupt \
> -		> /debug/tracing/set_ftrace_filter
> - # echo ftrace > /debug/tracing/current_tracer
> - # echo 1 > /debug/tracing/tracing_enabled
> +		> ./set_ftrace_filter
> + # echo ftrace > ./current_tracer
> + # echo 1 > ./tracing_enabled
>   # usleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > ./tracing_enabled
> + # cat ./trace
>  # tracer: ftrace
>  #
>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
> @@ -1568,7 +1577,7 @@ If I am only interested in sys_nanosleep and
> hrtimer_interrupt:
> 
>  To see which functions are being traced, you can cat the file:
> 
> - # cat /debug/tracing/set_ftrace_filter
> + # cat ./set_ftrace_filter
>  hrtimer_interrupt
>  sys_nanosleep
> 
> @@ -1588,7 +1597,7 @@ Note: It is better to use quotes to enclose the
> wild cards,
>        otherwise the shell may expand the parameters into names
>        of files in the local directory.
> 
> - # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
> + # echo 'hrtimer_*' > ./set_ftrace_filter
> 
>  Produces:
> 
> @@ -1609,7 +1618,7 @@ Produces:
> 
>  Notice that we lost the sys_nanosleep.
> 
> - # cat /debug/tracing/set_ftrace_filter
> + # cat ./set_ftrace_filter
>  hrtimer_run_queues
>  hrtimer_run_pending
>  hrtimer_init
> @@ -1635,17 +1644,17 @@ To append to the filters, use '>>'
>  To clear out a filter so that all functions will be recorded
>  again:
> 
> - # echo > /debug/tracing/set_ftrace_filter
> - # cat /debug/tracing/set_ftrace_filter
> + # echo > ./set_ftrace_filter
> + # cat ./set_ftrace_filter
>   #
> 
>  Again, now we want to append.
> 
> - # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
> - # cat /debug/tracing/set_ftrace_filter
> + # echo sys_nanosleep > ./set_ftrace_filter
> + # cat ./set_ftrace_filter
>  sys_nanosleep
> - # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
> - # cat /debug/tracing/set_ftrace_filter
> + # echo 'hrtimer_*' >> ./set_ftrace_filter
> + # cat ./set_ftrace_filter
>  hrtimer_run_queues
>  hrtimer_run_pending
>  hrtimer_init
> @@ -1668,7 +1677,7 @@ hrtimer_init_sleeper
>  The set_ftrace_notrace prevents those functions from being
>  traced.
> 
> - # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
> + # echo '*preempt*' '*lock*' > ./set_ftrace_notrace
> 
>  Produces:
> 
> @@ -1758,13 +1767,13 @@ the effect on the tracing is different. Every read from
>  trace_pipe is consumed. This means that subsequent reads will be
>  different. The trace is live.
> 
> - # echo function > /debug/tracing/current_tracer
> - # cat /debug/tracing/trace_pipe > /tmp/trace.out &
> + # echo function > ./current_tracer
> + # cat ./trace_pipe > /tmp/trace.out &
>  [1] 4153
> - # echo 1 > /debug/tracing/tracing_enabled
> + # echo 1 > ./tracing_enabled
>   # usleep 1
> - # echo 0 > /debug/tracing/tracing_enabled
> - # cat /debug/tracing/trace
> + # echo 0 > ./tracing_enabled
> + # cat ./trace
>  # tracer: function
>  #
>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
> @@ -1800,7 +1809,7 @@ number listed is the number of entries that can
> be recorded per
>  CPU. To know the full size, multiply the number of possible CPUS
>  with the number of entries.
> 
> - # cat /debug/tracing/buffer_size_kb
> + # cat ./buffer_size_kb
>  1408 (units kilobytes)
> 
>  Note, to modify this, you must have tracing completely disabled.
> @@ -1808,21 +1817,21 @@ To do that, echo "nop" into the current_tracer. If the
>  current_tracer is not set to "nop", an EINVAL error will be
>  returned.
> 
> - # echo nop > /debug/tracing/current_tracer
> - # echo 10000 > /debug/tracing/buffer_size_kb
> - # cat /debug/tracing/buffer_size_kb
> + # echo nop > ./current_tracer
> + # echo 10000 > ./buffer_size_kb
> + # cat ./buffer_size_kb
>  10000 (units kilobytes)
> 
>  The number of pages which will be allocated is limited to a
>  percentage of available memory. Allocating too much will produce
>  an error.
> 
> - # echo 1000000000000 > /debug/tracing/buffer_size_kb
> + # echo 1000000000000 > ./buffer_size_kb
>  -bash: echo: write error: Cannot allocate memory
> - # cat /debug/tracing/buffer_size_kb
> + # cat ./buffer_size_kb
>  85
> 
>  ---
> 
> On Sat, May 30, 2009 at 1:48 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> >
> >
> > On Sat, 30 May 2009, GeunSik Lim wrote:
> >
> >>
> >>
> >> Dear Greg and Steen,
> >>
> >> Thanks your advices and opinions about a confusion according to
> >> too many mount directory names for debugfs. I made rfc v2 patch file again like belows.
> >> Can I hear your advices about below patch contents?.
> >>
> >> * ref:
> >> http://groups.google.com/group/linux.kernel/browse_thread/thread/c34e386587979340/dc52317f888e78b6?#dc52317f888e78b6
> >>
> >>
> >> Regards,
> >> GeunSik Lim.
> >>
> >> Subject: [PATCH]   Fix terminology inconsistency of dir name to mount debugfs filesystem.
> >>
> >>       Many developers use "/debug/" or "/debugfs/ directory name to mount
> >>       debugfs filesystem for ftrace according to
> >>       ./Documentation/tracers/ftrace.txt file.
> >>
> >>       And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
> >>       existed in kernel source like ftrace, DRM, Wireless, Network[sky2]files
> >>       to mount debugfs filesystem.
> >>
> >>       debugfs means debug filesystem for debugging easy to use by greg kroah
> >>       hartman. "/sys/kernel/debug/" name is suitable as directory name
> >>       of debugfs filesystem.
> >>       -debugfs related reference: http://lwn.net/Articles/115405/
> >
> > Note, LWN has an update this week:
> >
> >  http://lwn.net/Articles/334546/
> >
> > But it currently is subscriber only. Others would need to either buy a
> > subscription (plug) or wait a week for it to become open.
> >
> > Still for some aspects, just having "debugfs" without the leading "/"
> > might just be self explanatory. We can assume the user already knows where
> > debugfs is mounted.
> >
> > -- Steve
> >
> >
> >>
> >>       Fix inconsistency of directory name to mount debugfs filesystem.
> >>
> >>          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
> >>          Acked-By: Inaky Perez-Gonzalez <inaky@linux.intel.com>
> >>          CC: Greg KH <greg@kroah.com>
> >>          CC: Steven Rostedt <rostedt@goodmis.org>
> >>          CC: linux-kernel <linux-kernel@vger.kernel.org>
> >
> 
> 
> 
> -- 
> Regards,
> GeunSik Lim ( SAMSUNG ELECTRONICS)
> Blog : http://blog.naver.com/invain/
> e-Mail: geunsik.lim@samsung.com
>            leemgs@gmail.com , leemgs1@gmail.com
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

On Sat, May 30, 2009 at 11:28 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Sat, 30 May 2009, GeunSik Lim wrote:
>
>> Thanks your advice. I agree with your reply about this patch.
>> I updated contents that you advised like belows.
>> If I mistake, Please correct me.
>>
>> And, I also need your review  about below 2 contents in the ftrace.txt file.
>>
>> Thanks,
>> GeunSik Lim.
>>
>>
>> 1)
>> @@ -1146,7 +1158,7 @@ int trace_fd;
>>  [...]
>>  int main(int argc, char *argv[]) {
>>       [...]
>> -     trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
>> +     trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
>>       [...]
>>       if (condition_hit()) {
>>               write(trace_fd, "0", 1);
>> @@ -1154,26 +1166,23 @@ int main(int argc, char *argv[]) {
>>       [...]
>>  }
>>
>>
>> @@ -1217,12 +1226,12 @@ int main (int argc, char **argv)
>>                  char line[64];
>>                  int s;
>>
>> -                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
>> +                ffd =
>> open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
>>                  if (ffd < 0)
>>                          exit(-1);
>>                  write(ffd, "nop", 3);
>>
>> -                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
>> +                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid",
>> O_WRONLY);
>>                  s = sprintf(line, "%d\n", getpid());
>>                  write(fd, line, s);
>> -Note: Here we hard coded the path name. The debugfs mount is not
>> -guaranteed to be at /debug (and is more commonly at
>> -/sys/kernel/debug). For simple one time traces, the above is
>> -sufficent. For anything else, a search through /proc/mounts may
>> +Note: Here we hard coded the path name. A search through /proc/mounts may
>>  be needed to find where the debugfs file-system is mounted.
>
> Here's the function I use:
>
> #define _STR(x) x
> #define STR(x) _STR(x)
> #define MAX_PATH 256
>
> const char *find_debugfs(void)
> {
>        static char debugfs[MAX_PATH+1];
>        static int debugfs_found;
>        char type[100];
>        FILE *fp;
>
>        if (debugfs_found)
>                return debugfs;
>
>
>        if ((fp = fopen("/proc/mounts","r")) == NULL) {
>                perror("/proc/mounts");
>                return NULL;
>        }
>
>        while (fscanf(fp, "%*s %"
>                      STR(MAX_PATH)
>                      "s %99s %*s %*d %*d\n",
>                      debugfs, type) == 2) {
>                if (strcmp(type, "debugfs") == 0)
>                        break;
>        }
>        fclose(fp);
>
>        if (strcmp(type, "debugfs") != 0) {
>                fprintf(stderr, "debugfs not mounted");
>                return NULL;
>        }
>
>        debugfs_found = 1;
>
>        return debugfs;
> }
>
> This might be a good idea to show it. This is the most robust since it
> does not hard code the debugfs directory.
Yes, I think so. I have one opinion in the above find_debugfs() function.
Default directory  is "/sys/kernel/debug/tracing" in ftrace.txt file
as you mentioned.
I will append  below code for "***/tracing/" directory name.

         int size;
         [...]
         size = MAX_PATH - strlen(debugfs);
         strncat(debugfs, "/tracing/", size);
         return debugfs;
>
>>
>> 2)
>> More details can be found in the source code, in the
>> -kernel/tracing/*.c files.
>> +kernel/trace/*.c files
>>
>>
>>
>> * about ftrace.txt file
>> ---
>> diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
>> index fd9a3e6..790199b 100644
>> --- a/Documentation/trace/ftrace.txt
>> +++ b/Documentation/trace/ftrace.txt
>> @@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
>>                 (dual licensed under the GPL v2)
>>  Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
>>            John Kacur, and David Teigland.
>> -
>>  Written for: 2.6.28-rc2
>>
>>  Introduction
>> @@ -33,13 +32,26 @@ The File System
>>  Ftrace uses the debugfs file system to hold the control files as
>>  well as the files to display output.
>>
>> -To mount the debugfs system:
>> +When debugfs is configured into the kernel (which selecting any ftrace
>> +option will do) the directory /sys/kernel/debug will be created. To mount
>> +this directory, you can add to your /etc/fstab file:
>> +
>> + debugfs       /sys/kernel/debug          debugfs defaults        0       0
>> +
>> +Or you can mount it at run time with:
>> +
>> + mount -t debugfs nodev /sys/kernel/debug
>> +
>> +For quicker access to that directory you may want to make a soft link to
>> +it:
>>
>> -  # mkdir /debug
>> -  # mount -t debugfs nodev /debug
>> + ln -s /sys/kernel/debug /debug
>>
>> -( Note: it is more common to mount at /sys/kernel/debug, but for
>> -  simplicity this document will use /debug)
>> +Any selected ftrace option will also create a directory called tracing
>> +within the debugfs. The rest of the document will assume that you are in
>> +the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
>> +on the files within that directory and not distract from the content with
>> +the extended "/sys/kernel/debug/tracing" path name.
>>
>>  That's it! (assuming that you have ftrace configured into your kernel)
>>
>> @@ -389,18 +401,18 @@ trace_options
>>  The trace_options file is used to control what gets printed in
>>  the trace output. To see what is available, simply cat the file:
>>
>> -  cat /debug/tracing/trace_options
>> +  cat ./trace_options
>
> Please remove the "./", it is also distracting. We state that we "cd" to
> the location. "cat trace_options" is good enough.
It's right. This is just my private style. I will  remove "./".
>
> Same for the all the others below.
>
> Also, since I'm the most picky about this, you may want to remove the
> ftrace files from the patch and move it to another patch. That way the
I am not think that you are the most picky about this. I like your advice and
review about my proposal for consensus.
> owners of the other files can ack them and get those changes in. When we
> have something for ftrace, I'll give my ack. But lets not hold up the
> other changes because of me ;-)
>
Don't care. Hope it helps. ;-)
I will modify  ftrace files from the patch according to your advice.

> -- Steve
>
>>    print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
>>    noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj
>>
>>  To disable one of the options, echo in the option prepended with
>>  "no".
>>
>> -  echo noprint-parent > /debug/tracing/trace_options
>> +  echo noprint-parent > ./trace_options
>>
>>  To enable an option, leave off the "no".
>>
>> -  echo sym-offset > /debug/tracing/trace_options
>> +  echo sym-offset > ./trace_options
>>
>>  Here are the available options:
>>
>> @@ -476,11 +488,11 @@ sched_switch
>>  This tracer simply records schedule switches. Here is an example
>>  of how to use it.
>>
>> - # echo sched_switch > /debug/tracing/current_tracer
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo sched_switch > ./current_tracer
>> + # echo 1 > ./tracing_enabled
>>   # sleep 1
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./trace
>>
>>  # tracer: sched_switch
>>  #
>> @@ -574,13 +586,13 @@ new trace is saved.
>>  To reset the maximum, echo 0 into tracing_max_latency. Here is
>>  an example:
>>
>> - # echo irqsoff > /debug/tracing/current_tracer
>> - # echo 0 > /debug/tracing/tracing_max_latency
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo irqsoff > ./current_tracer
>> + # echo 0 > ./tracing_max_latency
>> + # echo 1 > ./tracing_enabled
>>   # ls -ltr
>>   [...]
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/latency_trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./latency_trace
>>  # tracer: irqsoff
>>  #
>>  irqsoff latency trace v1.1.5 on 2.6.26
>> @@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum
>> latency for
>>  which preemption was disabled. The control of preemptoff tracer
>>  is much like the irqsoff tracer.
>>
>> - # echo preemptoff > /debug/tracing/current_tracer
>> - # echo 0 > /debug/tracing/tracing_max_latency
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo preemptoff > ./current_tracer
>> + # echo 0 > ./tracing_max_latency
>> + # echo 1 > ./tracing_enabled
>>   # ls -ltr
>>   [...]
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/latency_trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./latency_trace
>>  # tracer: preemptoff
>>  #
>>  preemptoff latency trace v1.1.5 on 2.6.26-rc8
>> @@ -828,13 +840,13 @@ tracer.
>>  Again, using this trace is much like the irqsoff and preemptoff
>>  tracers.
>>
>> - # echo preemptirqsoff > /debug/tracing/current_tracer
>> - # echo 0 > /debug/tracing/tracing_max_latency
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo preemptirqsoff > ./current_tracer
>> + # echo 0 > ./tracing_max_latency
>> + # echo 1 > ./tracing_enabled
>>   # ls -ltr
>>   [...]
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/latency_trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./latency_trace
>>  # tracer: preemptirqsoff
>>  #
>>  preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
>> @@ -990,12 +1002,12 @@ slightly differently than we did with the
>> previous tracers.
>>  Instead of performing an 'ls', we will run 'sleep 1' under
>>  'chrt' which changes the priority of the task.
>>
>> - # echo wakeup > /debug/tracing/current_tracer
>> - # echo 0 > /debug/tracing/tracing_max_latency
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo wakeup > ./current_tracer
>> + # echo 0 > ./tracing_max_latency
>> + # echo 1 > ./tracing_enabled
>>   # chrt -f 5 sleep 1
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/latency_trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./latency_trace
>>  # tracer: wakeup
>>  #
>>  wakeup latency trace v1.1.5 on 2.6.26-rc8
>> @@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
>>  ftrace_enabled is set; otherwise this tracer is a nop.
>>
>>   # sysctl kernel.ftrace_enabled=1
>> - # echo function > /debug/tracing/current_tracer
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo function > ./current_tracer
>> + # echo 1 > ./tracing_enabled
>>   # usleep 1
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./trace
>>  # tracer: function
>>  #
>>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
>> @@ -1146,7 +1158,7 @@ int trace_fd;
>>  [...]
>>  int main(int argc, char *argv[]) {
>>       [...]
>> -     trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
>> +     trace_fd = open("/sys/kernel/debug/tracing/tracing_enabled", O_WRONLY);
>>       [...]
>>       if (condition_hit()) {
>>               write(trace_fd, "0", 1);
>> @@ -1154,26 +1166,23 @@ int main(int argc, char *argv[]) {
>>       [...]
>>  }
>>
>> -Note: Here we hard coded the path name. The debugfs mount is not
>> -guaranteed to be at /debug (and is more commonly at
>> -/sys/kernel/debug). For simple one time traces, the above is
>> -sufficent. For anything else, a search through /proc/mounts may
>> +Note: Here we hard coded the path name. A search through /proc/mounts may
>>  be needed to find where the debugfs file-system is mounted.
>>
>>
>>  Single thread tracing
>>  ---------------------
>>
>> -By writing into /debug/tracing/set_ftrace_pid you can trace a
>> +By writing into ./set_ftrace_pid you can trace a
>>  single thread. For example:
>>
>> -# cat /debug/tracing/set_ftrace_pid
>> +# cat ./set_ftrace_pid
>>  no pid
>> -# echo 3111 > /debug/tracing/set_ftrace_pid
>> -# cat /debug/tracing/set_ftrace_pid
>> +# echo 3111 > ./set_ftrace_pid
>> +# cat ./set_ftrace_pid
>>  3111
>> -# echo function > /debug/tracing/current_tracer
>> -# cat /debug/tracing/trace | head
>> +# echo function > ./current_tracer
>> +# cat ./trace | head
>>   # tracer: function
>>   #
>>   #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
>> @@ -1184,8 +1193,8 @@ no pid
>>       yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base
>> <-hrtimer_try_to_cancel
>>       yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
>>       yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
>> -# echo -1 > /debug/tracing/set_ftrace_pid
>> -# cat /debug/tracing/trace |head
>> +# echo -1 > ./set_ftrace_pid
>> +# cat ./trace |head
>>   # tracer: function
>>   #
>>   #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
>> @@ -1217,12 +1226,12 @@ int main (int argc, char **argv)
>>                  char line[64];
>>                  int s;
>>
>> -                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
>> +                ffd =
>> open("/sys/kernel/debug/tracing/current_tracer", O_WRONLY);
>>                  if (ffd < 0)
>>                          exit(-1);
>>                  write(ffd, "nop", 3);
>>
>> -                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
>> +                fd = open("/sys/kernel/debug/tracing/set_ftrace_pid",
>> O_WRONLY);
>>                  s = sprintf(line, "%d\n", getpid());
>>                  write(fd, line, s);
>>
>> @@ -1374,22 +1383,22 @@ want, depending on your needs.
>>    tracing_cpu_mask file) or you might sometimes see unordered
>>    function calls while cpu tracing switch.
>>
>> -     hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
>> -     show: echo funcgraph-cpu > /debug/tracing/trace_options
>> +     hide: echo nofuncgraph-cpu > ./trace_options
>> +     show: echo funcgraph-cpu > ./trace_options
>>
>>  - The duration (function's time of execution) is displayed on
>>    the closing bracket line of a function or on the same line
>>    than the current function in case of a leaf one. It is default
>>    enabled.
>>
>> -     hide: echo nofuncgraph-duration > /debug/tracing/trace_options
>> -     show: echo funcgraph-duration > /debug/tracing/trace_options
>> +     hide: echo nofuncgraph-duration > ./trace_options
>> +     show: echo funcgraph-duration > ./trace_options
>>
>>  - The overhead field precedes the duration field in case of
>>    reached duration thresholds.
>>
>> -     hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
>> -     show: echo funcgraph-overhead > /debug/tracing/trace_options
>> +     hide: echo nofuncgraph-overhead > ./trace_options
>> +     show: echo funcgraph-overhead > ./trace_options
>>       depends on: funcgraph-duration
>>
>>    ie:
>> @@ -1418,8 +1427,8 @@ want, depending on your needs.
>>  - The task/pid field displays the thread cmdline and pid which
>>    executed the function. It is default disabled.
>>
>> -     hide: echo nofuncgraph-proc > /debug/tracing/trace_options
>> -     show: echo funcgraph-proc > /debug/tracing/trace_options
>> +     hide: echo nofuncgraph-proc > ./trace_options
>> +     show: echo funcgraph-proc > ./trace_options
>>
>>    ie:
>>
>> @@ -1442,8 +1451,8 @@ want, depending on your needs.
>>    system clock since it started. A snapshot of this time is
>>    given on each entry/exit of functions
>>
>> -     hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
>> -     show: echo funcgraph-abstime > /debug/tracing/trace_options
>> +     hide: echo nofuncgraph-abstime > ./trace_options
>> +     show: echo funcgraph-abstime > ./trace_options
>>
>>    ie:
>>
>> @@ -1540,7 +1549,7 @@ listed in:
>>
>>     available_filter_functions
>>
>> - # cat /debug/tracing/available_filter_functions
>> + # cat ./available_filter_functions
>>  put_prev_task_idle
>>  kmem_cache_create
>>  pick_next_task_rt
>> @@ -1552,12 +1561,12 @@ mutex_lock
>>  If I am only interested in sys_nanosleep and hrtimer_interrupt:
>>
>>   # echo sys_nanosleep hrtimer_interrupt \
>> -             > /debug/tracing/set_ftrace_filter
>> - # echo ftrace > /debug/tracing/current_tracer
>> - # echo 1 > /debug/tracing/tracing_enabled
>> +             > ./set_ftrace_filter
>> + # echo ftrace > ./current_tracer
>> + # echo 1 > ./tracing_enabled
>>   # usleep 1
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./trace
>>  # tracer: ftrace
>>  #
>>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
>> @@ -1568,7 +1577,7 @@ If I am only interested in sys_nanosleep and
>> hrtimer_interrupt:
>>
>>  To see which functions are being traced, you can cat the file:
>>
>> - # cat /debug/tracing/set_ftrace_filter
>> + # cat ./set_ftrace_filter
>>  hrtimer_interrupt
>>  sys_nanosleep
>>
>> @@ -1588,7 +1597,7 @@ Note: It is better to use quotes to enclose the
>> wild cards,
>>        otherwise the shell may expand the parameters into names
>>        of files in the local directory.
>>
>> - # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
>> + # echo 'hrtimer_*' > ./set_ftrace_filter
>>
>>  Produces:
>>
>> @@ -1609,7 +1618,7 @@ Produces:
>>
>>  Notice that we lost the sys_nanosleep.
>>
>> - # cat /debug/tracing/set_ftrace_filter
>> + # cat ./set_ftrace_filter
>>  hrtimer_run_queues
>>  hrtimer_run_pending
>>  hrtimer_init
>> @@ -1635,17 +1644,17 @@ To append to the filters, use '>>'
>>  To clear out a filter so that all functions will be recorded
>>  again:
>>
>> - # echo > /debug/tracing/set_ftrace_filter
>> - # cat /debug/tracing/set_ftrace_filter
>> + # echo > ./set_ftrace_filter
>> + # cat ./set_ftrace_filter
>>   #
>>
>>  Again, now we want to append.
>>
>> - # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
>> - # cat /debug/tracing/set_ftrace_filter
>> + # echo sys_nanosleep > ./set_ftrace_filter
>> + # cat ./set_ftrace_filter
>>  sys_nanosleep
>> - # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
>> - # cat /debug/tracing/set_ftrace_filter
>> + # echo 'hrtimer_*' >> ./set_ftrace_filter
>> + # cat ./set_ftrace_filter
>>  hrtimer_run_queues
>>  hrtimer_run_pending
>>  hrtimer_init
>> @@ -1668,7 +1677,7 @@ hrtimer_init_sleeper
>>  The set_ftrace_notrace prevents those functions from being
>>  traced.
>>
>> - # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
>> + # echo '*preempt*' '*lock*' > ./set_ftrace_notrace
>>
>>  Produces:
>>
>> @@ -1758,13 +1767,13 @@ the effect on the tracing is different. Every read from
>>  trace_pipe is consumed. This means that subsequent reads will be
>>  different. The trace is live.
>>
>> - # echo function > /debug/tracing/current_tracer
>> - # cat /debug/tracing/trace_pipe > /tmp/trace.out &
>> + # echo function > ./current_tracer
>> + # cat ./trace_pipe > /tmp/trace.out &
>>  [1] 4153
>> - # echo 1 > /debug/tracing/tracing_enabled
>> + # echo 1 > ./tracing_enabled
>>   # usleep 1
>> - # echo 0 > /debug/tracing/tracing_enabled
>> - # cat /debug/tracing/trace
>> + # echo 0 > ./tracing_enabled
>> + # cat ./trace
>>  # tracer: function
>>  #
>>  #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
>> @@ -1800,7 +1809,7 @@ number listed is the number of entries that can
>> be recorded per
>>  CPU. To know the full size, multiply the number of possible CPUS
>>  with the number of entries.
>>
>> - # cat /debug/tracing/buffer_size_kb
>> + # cat ./buffer_size_kb
>>  1408 (units kilobytes)
>>
>>  Note, to modify this, you must have tracing completely disabled.
>> @@ -1808,21 +1817,21 @@ To do that, echo "nop" into the current_tracer. If the
>>  current_tracer is not set to "nop", an EINVAL error will be
>>  returned.
>>
>> - # echo nop > /debug/tracing/current_tracer
>> - # echo 10000 > /debug/tracing/buffer_size_kb
>> - # cat /debug/tracing/buffer_size_kb
>> + # echo nop > ./current_tracer
>> + # echo 10000 > ./buffer_size_kb
>> + # cat ./buffer_size_kb
>>  10000 (units kilobytes)
>>
>>  The number of pages which will be allocated is limited to a
>>  percentage of available memory. Allocating too much will produce
>>  an error.
>>
>> - # echo 1000000000000 > /debug/tracing/buffer_size_kb
>> + # echo 1000000000000 > ./buffer_size_kb
>>  -bash: echo: write error: Cannot allocate memory
>> - # cat /debug/tracing/buffer_size_kb
>> + # cat ./buffer_size_kb
>>  85
>>
>>  ---
>>
>> On Sat, May 30, 2009 at 1:48 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
>> >
>> >
>> >
>> > On Sat, 30 May 2009, GeunSik Lim wrote:
>> >
>> >>
>> >>
>> >> Dear Greg and Steen,
>> >>
>> >> Thanks your advices and opinions about a confusion according to
>> >> too many mount directory names for debugfs. I made rfc v2 patch file again like belows.
>> >> Can I hear your advices about below patch contents?.
>> >>
>> >> * ref:
>> >> http://groups.google.com/group/linux.kernel/browse_thread/thread/c34e386587979340/dc52317f888e78b6?#dc52317f888e78b6
>> >>
>> >>
>> >> Regards,
>> >> GeunSik Lim.
>> >>
>> >> Subject: [PATCH]   Fix terminology inconsistency of dir name to mount debugfs filesystem.
>> >>
>> >>       Many developers use "/debug/" or "/debugfs/ directory name to mount
>> >>       debugfs filesystem for ftrace according to
>> >>       ./Documentation/tracers/ftrace.txt file.
>> >>
>> >>       And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
>> >>       existed in kernel source like ftrace, DRM, Wireless, Network[sky2]files
>> >>       to mount debugfs filesystem.
>> >>
>> >>       debugfs means debug filesystem for debugging easy to use by greg kroah
>> >>       hartman. "/sys/kernel/debug/" name is suitable as directory name
>> >>       of debugfs filesystem.
>> >>       -debugfs related reference: http://lwn.net/Articles/115405/
>> >
>> > Note, LWN has an update this week:
>> >
>> >  http://lwn.net/Articles/334546/
>> >
>> > But it currently is subscriber only. Others would need to either buy a
>> > subscription (plug) or wait a week for it to become open.
>> >
>> > Still for some aspects, just having "debugfs" without the leading "/"
>> > might just be self explanatory. We can assume the user already knows where
>> > debugfs is mounted.
>> >
>> > -- Steve
>> >
>> >
>> >>
>> >>       Fix inconsistency of directory name to mount debugfs filesystem.
>> >>
>> >>          Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
>> >>          Acked-By: Inaky Perez-Gonzalez <inaky@linux.intel.com>
>> >>          CC: Greg KH <greg@kroah.com>
>> >>          CC: Steven Rostedt <rostedt@goodmis.org>
>> >>          CC: linux-kernel <linux-kernel@vger.kernel.org>
>> >
>>
>>
>>
>> --
>> Regards,
>> GeunSik Lim ( SAMSUNG ELECTRONICS)
>> Blog : http://blog.naver.com/invain/
>> e-Mail: geunsik.lim@samsung.com
>>            leemgs@gmail.com , leemgs1@gmail.com
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
>>



-- 
Regards,
GeunSik Lim ( SAMSUNG ELECTRONICS)
Blog : http://blog.naver.com/invain/
e-Mail: geunsik.lim@samsung.com
           leemgs@gmail.com , leemgs1@gmail.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

On Sat, May 30, 2009 at 6:38 PM, GeunSik Lim <leemgs1@gmail.com> wrote:
>> Also, since I'm the most picky about this, you may want to remove the
>> ftrace files from the patch and move it to another patch. That way the
> I am not think that you are the most picky about this. I like your advice and
> review about my proposal for consensus.
>> owners of the other files can ack them and get those changes in. When we
>> have something for ftrace, I'll give my ack. But lets not hold up the
>> other changes because of me ;-)
>>
> Don't care. Hope it helps. ;-)
> I will modify  ftrace files from the patch according to your advice.

I updated ftrace related contents according to  Steven's help like belows.
If I misunderstood wrongly, Please correct me.
Thanks.

* About ftrace.txt file/
---
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..caaf5d9 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
                (dual licensed under the GPL v2)
 Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
 	     John Kacur, and David Teigland.
-
 Written for: 2.6.28-rc2

 Introduction
@@ -33,13 +32,26 @@ The File System
 Ftrace uses the debugfs file system to hold the control files as
 well as the files to display output.

-To mount the debugfs system:
+When debugfs is configured into the kernel (which selecting any ftrace
+option will do) the directory /sys/kernel/debug will be created. To mount
+this directory, you can add to your /etc/fstab file:
+
+ debugfs       /sys/kernel/debug          debugfs defaults        0       0
+
+Or you can mount it at run time with:
+
+ mount -t debugfs nodev /sys/kernel/debug
+
+For quicker access to that directory you may want to make a soft link to
+it:

-  # mkdir /debug
-  # mount -t debugfs nodev /debug
+ ln -s /sys/kernel/debug /debug

-( Note: it is more common to mount at /sys/kernel/debug, but for
-  simplicity this document will use /debug)
+Any selected ftrace option will also create a directory called tracing
+within the debugfs. The rest of the document will assume that you are in
+the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
+on the files within that directory and not distract from the content with
+the extended "/sys/kernel/debug/tracing" path name.

 That's it! (assuming that you have ftrace configured into your kernel)

@@ -389,18 +401,18 @@ trace_options
 The trace_options file is used to control what gets printed in
 the trace output. To see what is available, simply cat the file:

-  cat /debug/tracing/trace_options
+  cat trace_options
   print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
   noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj

 To disable one of the options, echo in the option prepended with
 "no".

-  echo noprint-parent > /debug/tracing/trace_options
+  echo noprint-parent > trace_options

 To enable an option, leave off the "no".

-  echo sym-offset > /debug/tracing/trace_options
+  echo sym-offset > trace_options

 Here are the available options:

@@ -476,11 +488,11 @@ sched_switch
 This tracer simply records schedule switches. Here is an example
 of how to use it.

- # echo sched_switch > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo sched_switch > current_tracer
+ # echo 1 > tracing_enabled
  # sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace

 # tracer: sched_switch
 #
@@ -574,13 +586,13 @@ new trace is saved.
 To reset the maximum, echo 0 into tracing_max_latency. Here is
 an example:

- # echo irqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo irqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: irqsoff
 #
 irqsoff latency trace v1.1.5 on 2.6.26
@@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum
latency for
 which preemption was disabled. The control of preemptoff tracer
 is much like the irqsoff tracer.

- # echo preemptoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptoff
 #
 preemptoff latency trace v1.1.5 on 2.6.26-rc8
@@ -828,13 +840,13 @@ tracer.
 Again, using this trace is much like the irqsoff and preemptoff
 tracers.

- # echo preemptirqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptirqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptirqsoff
 #
 preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
@@ -990,12 +1002,12 @@ slightly differently than we did with the
previous tracers.
 Instead of performing an 'ls', we will run 'sleep 1' under
 'chrt' which changes the priority of the task.

- # echo wakeup > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo wakeup > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # chrt -f 5 sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: wakeup
 #
 wakeup latency trace v1.1.5 on 2.6.26-rc8
@@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
 ftrace_enabled is set; otherwise this tracer is a nop.

  # sysctl kernel.ftrace_enabled=1
- # echo function > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo function > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1146,7 +1158,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open(find_debugfs("tracing_enabled"), O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1154,26 +1166,20 @@ int main(int argc, char *argv[]) {
 	[...]
 }

-Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
-/sys/kernel/debug). For simple one time traces, the above is
-sufficent. For anything else, a search through /proc/mounts may
-be needed to find where the debugfs file-system is mounted.
-

 Single thread tracing
 ---------------------

-By writing into /debug/tracing/set_ftrace_pid you can trace a
+By writing into set_ftrace_pid you can trace a
 single thread. For example:

-# cat /debug/tracing/set_ftrace_pid
+# cat set_ftrace_pid
 no pid
-# echo 3111 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/set_ftrace_pid
+# echo 3111 > set_ftrace_pid
+# cat set_ftrace_pid
 3111
-# echo function > /debug/tracing/current_tracer
-# cat /debug/tracing/trace | head
+# echo function > current_tracer
+# cat trace | head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1184,8 +1190,8 @@ no pid
      yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base
<-hrtimer_try_to_cancel
      yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
      yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
-# echo -1 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/trace |head
+# echo -1 > set_ftrace_pid
+# cat trace |head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1202,11 +1208,57 @@ something like this simple program:

 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>

+#define _STR(x) #x
+#define STR(x) _STR(x)
+#define MAX_PATH 256
+
+const char *find_debugfs(char *file_name)
+{
+       static char debugfs[MAX_PATH+1];
+       static int debugfs_found;
+       char type[100];
+       FILE *fp;
+       int size;
+
+       if (debugfs_found)
+               return debugfs;
+
+       if ((fp = fopen("/proc/mounts","r")) == NULL) {
+               perror("/proc/mounts");
+               return NULL;
+       }
+
+       while (fscanf(fp, "%*s %"
+                     STR(MAX_PATH)
+                     "s %99s %*s %*d %*d\n",
+                     debugfs, type) == 2) {
+               if (strcmp(type, "debugfs") == 0)
+                       break;
+       }
+       fclose(fp);
+
+       if (strcmp(type, "debugfs") != 0) {
+               fprintf(stderr, "debugfs not mounted");
+               return NULL;
+       }
+
+       debugfs_found = 1;
+
+       size = MAX_PATH - strlen(debugfs);
+       strncat(debugfs, "/tracing/", size);
+
+       size = MAX_PATH - strlen(debugfs);
+       strncat(debugfs, file_name, size);
+
+       return debugfs;
+}
+
 int main (int argc, char **argv)
 {
         if (argc < 1)
@@ -1217,12 +1269,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;

-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd = open(find_debugfs("current_tracer"), O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);

-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open(find_debugfs("set_ftrace_pid"), O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);

@@ -1374,22 +1426,22 @@ want, depending on your needs.
   tracing_cpu_mask file) or you might sometimes see unordered
   function calls while cpu tracing switch.

-	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
-	show: echo funcgraph-cpu > /debug/tracing/trace_options
+	hide: echo nofuncgraph-cpu > trace_options
+	show: echo funcgraph-cpu > trace_options

 - The duration (function's time of execution) is displayed on
   the closing bracket line of a function or on the same line
   than the current function in case of a leaf one. It is default
   enabled.

-	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
-	show: echo funcgraph-duration > /debug/tracing/trace_options
+	hide: echo nofuncgraph-duration > trace_options
+	show: echo funcgraph-duration > trace_options

 - The overhead field precedes the duration field in case of
   reached duration thresholds.

-	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
-	show: echo funcgraph-overhead > /debug/tracing/trace_options
+	hide: echo nofuncgraph-overhead > trace_options
+	show: echo funcgraph-overhead > trace_options
 	depends on: funcgraph-duration

   ie:
@@ -1418,8 +1470,8 @@ want, depending on your needs.
 - The task/pid field displays the thread cmdline and pid which
   executed the function. It is default disabled.

-	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
-	show: echo funcgraph-proc > /debug/tracing/trace_options
+	hide: echo nofuncgraph-proc > trace_options
+	show: echo funcgraph-proc > trace_options

   ie:

@@ -1442,8 +1494,8 @@ want, depending on your needs.
   system clock since it started. A snapshot of this time is
   given on each entry/exit of functions

-	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
-	show: echo funcgraph-abstime > /debug/tracing/trace_options
+	hide: echo nofuncgraph-abstime > trace_options
+	show: echo funcgraph-abstime > trace_options

   ie:

@@ -1540,7 +1592,7 @@ listed in:

    available_filter_functions

- # cat /debug/tracing/available_filter_functions
+ # cat available_filter_functions
 put_prev_task_idle
 kmem_cache_create
 pick_next_task_rt
@@ -1552,12 +1604,12 @@ mutex_lock
 If I am only interested in sys_nanosleep and hrtimer_interrupt:

  # echo sys_nanosleep hrtimer_interrupt \
-		> /debug/tracing/set_ftrace_filter
- # echo ftrace > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+		> set_ftrace_filter
+ # echo ftrace > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: ftrace
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1568,7 +1620,7 @@ If I am only interested in sys_nanosleep and
hrtimer_interrupt:

 To see which functions are being traced, you can cat the file:

- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_interrupt
 sys_nanosleep

@@ -1588,7 +1640,7 @@ Note: It is better to use quotes to enclose the
wild cards,
       otherwise the shell may expand the parameters into names
       of files in the local directory.

- # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' > set_ftrace_filter

 Produces:

@@ -1609,7 +1661,7 @@ Produces:

 Notice that we lost the sys_nanosleep.

- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1635,17 +1687,17 @@ To append to the filters, use '>>'
 To clear out a filter so that all functions will be recorded
 again:

- # echo > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo > set_ftrace_filter
+ # cat set_ftrace_filter
  #

 Again, now we want to append.

- # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo sys_nanosleep > set_ftrace_filter
+ # cat set_ftrace_filter
 sys_nanosleep
- # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' >> set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1668,7 +1720,7 @@ hrtimer_init_sleeper
 The set_ftrace_notrace prevents those functions from being
 traced.

- # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+ # echo '*preempt*' '*lock*' > set_ftrace_notrace

 Produces:

@@ -1758,13 +1810,13 @@ the effect on the tracing is different. Every read from
 trace_pipe is consumed. This means that subsequent reads will be
 different. The trace is live.

- # echo function > /debug/tracing/current_tracer
- # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+ # echo function > current_tracer
+ # cat trace_pipe > /tmp/trace.out &
 [1] 4153
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1800,7 +1852,7 @@ number listed is the number of entries that can
be recorded per
 CPU. To know the full size, multiply the number of possible CPUS
 with the number of entries.

- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 1408 (units kilobytes)

 Note, to modify this, you must have tracing completely disabled.
@@ -1808,18 +1860,18 @@ To do that, echo "nop" into the current_tracer. If the
 current_tracer is not set to "nop", an EINVAL error will be
 returned.

- # echo nop > /debug/tracing/current_tracer
- # echo 10000 > /debug/tracing/buffer_size_kb
- # cat /debug/tracing/buffer_size_kb
+ # echo nop > current_tracer
+ # echo 10000 > buffer_size_kb
+ # cat buffer_size_kb
 10000 (units kilobytes)

 The number of pages which will be allocated is limited to a
 percentage of available memory. Allocating too much will produce
 an error.

- # echo 1000000000000 > /debug/tracing/buffer_size_kb
+ # echo 1000000000000 > buffer_size_kb
 -bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 85

---



Regards,
GeunSik Lim ( SAMSUNG ELECTRONICS)
Blog : http://blog.naver.com/invain/
e-Mail: geunsik.lim@samsung.com
           leemgs@gmail.com , leemgs1@gmail.com

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Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 1907 bytes --]


On Sat, 30 May 2009, GeunSik Lim wrote:
> > Here's the function I use:
> >
> > #define _STR(x) x
> > #define STR(x) _STR(x)
> > #define MAX_PATH 256
> >
> > const char *find_debugfs(void)
> > {
> >        static char debugfs[MAX_PATH+1];
> >        static int debugfs_found;
> >        char type[100];
> >        FILE *fp;
> >
> >        if (debugfs_found)
> >                return debugfs;
> >
> >
> >        if ((fp = fopen("/proc/mounts","r")) == NULL) {
> >                perror("/proc/mounts");
> >                return NULL;
> >        }
> >
> >        while (fscanf(fp, "%*s %"
> >                      STR(MAX_PATH)
> >                      "s %99s %*s %*d %*d\n",
> >                      debugfs, type) == 2) {
> >                if (strcmp(type, "debugfs") == 0)
> >                        break;
> >        }
> >        fclose(fp);
> >
> >        if (strcmp(type, "debugfs") != 0) {
> >                fprintf(stderr, "debugfs not mounted");
> >                return NULL;
> >        }
> >
> >        debugfs_found = 1;
> >
> >        return debugfs;
> > }
> >
> > This might be a good idea to show it. This is the most robust since it
> > does not hard code the debugfs directory.
> Yes, I think so. I have one opinion in the above find_debugfs() function.
> Default directory  is "/sys/kernel/debug/tracing" in ftrace.txt file
> as you mentioned.
> I will append  below code for "***/tracing/" directory name.
> 
>          int size;
>          [...]
>          size = MAX_PATH - strlen(debugfs);
>          strncat(debugfs, "/tracing/", size);
>          return debugfs;

Heh, I usually have another function to add the /tracing part. But sure, 
we could do that too.

-- Steve

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[Steven Rostedt]

On Sat, 30 May 2009, GeunSik Lim wrote:
> @@ -1202,11 +1208,57 @@ something like this simple program:
> 
>  #include <stdio.h>
>  #include <stdlib.h>
> +#include <string.h>
>  #include <sys/types.h>
>  #include <sys/stat.h>
>  #include <fcntl.h>
>  #include <unistd.h>
> 
> +#define _STR(x) #x
> +#define STR(x) _STR(x)
> +#define MAX_PATH 256
> +
> +const char *find_debugfs(char *file_name)
> +{
> +       static char debugfs[MAX_PATH+1];
> +       static int debugfs_found;
> +       char type[100];
> +       FILE *fp;
> +       int size;
> +
> +       if (debugfs_found)
> +               return debugfs;
> +
> +       if ((fp = fopen("/proc/mounts","r")) == NULL) {
> +               perror("/proc/mounts");
> +               return NULL;
> +       }
> +
> +       while (fscanf(fp, "%*s %"
> +                     STR(MAX_PATH)
> +                     "s %99s %*s %*d %*d\n",
> +                     debugfs, type) == 2) {
> +               if (strcmp(type, "debugfs") == 0)
> +                       break;
> +       }
> +       fclose(fp);
> +
> +       if (strcmp(type, "debugfs") != 0) {
> +               fprintf(stderr, "debugfs not mounted");
> +               return NULL;
> +       }
> +
> +       debugfs_found = 1;
> +
> +       size = MAX_PATH - strlen(debugfs);
> +       strncat(debugfs, "/tracing/", size);
> +
> +       size = MAX_PATH - strlen(debugfs);
> +       strncat(debugfs, file_name, size);

You need to make two functions. One to find the debugfs and one to add the 
file. The "debugfs_found" will make the function return just the first 
file_name every time. Something like this: (remove the file_name from 
find_debugfs).

const char *tracing_file(const char *file_name)
{
	static char trace_file[MAX_PATH+1];

	snprintf(trace_file, MAX_PATH, "%s/%s", find_debugfs(), file_name);

	return trace_file;
}

The above is not thread safe, but is OK for non threaded programs.

-- Steve

> +
> +       return debugfs;
> +}
> +
>  int main (int argc, char **argv)
>  {
>          if (argc < 1)
> @@ -1217,12 +1269,12 @@ int main (int argc, char **argv)
>                  char line[64];
>                  int s;
> 
> -                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
> +                ffd = open(find_debugfs("current_tracer"), O_WRONLY);
>                  if (ffd < 0)
>                          exit(-1);
>                  write(ffd, "nop", 3);
> 
> -                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
> +                fd = open(find_debugfs("set_ftrace_pid"), O_WRONLY);
>                  s = sprintf(line, "%d\n", getpid());
>                  write(fd, line, s);
> 

Re: [RFC V2 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

On Sat, May 30, 2009 at 10:44 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
> You need to make two functions. One to find the debugfs and one to add the
> file. The "debugfs_found" will make the function return just the first
> file_name every time. Something like this: (remove the file_name from
> find_debugfs).
>
> const char *tracing_file(const char *file_name)
> {
>        static char trace_file[MAX_PATH+1];
>
>        snprintf(trace_file, MAX_PATH, "%s/%s", find_debugfs(), file_name);
>
>        return trace_file;
> }
>
> The above is not thread safe, but is OK for non threaded programs.
Thanks.
I modified pseudo code using tracing_file function that you sent.

* ftrace.txt info after modification.
---
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..05f8378 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
                (dual licensed under the GPL v2)
 Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
 	     John Kacur, and David Teigland.
-
 Written for: 2.6.28-rc2

 Introduction
@@ -33,13 +32,26 @@ The File System
 Ftrace uses the debugfs file system to hold the control files as
 well as the files to display output.

-To mount the debugfs system:
+When debugfs is configured into the kernel (which selecting any ftrace
+option will do) the directory /sys/kernel/debug will be created. To mount
+this directory, you can add to your /etc/fstab file:
+
+ debugfs       /sys/kernel/debug          debugfs defaults        0       0
+
+Or you can mount it at run time with:
+
+ mount -t debugfs nodev /sys/kernel/debug

-  # mkdir /debug
-  # mount -t debugfs nodev /debug
+For quicker access to that directory you may want to make a soft link to
+it:

-( Note: it is more common to mount at /sys/kernel/debug, but for
-  simplicity this document will use /debug)
+ ln -s /sys/kernel/debug /debug
+
+Any selected ftrace option will also create a directory called tracing
+within the debugfs. The rest of the document will assume that you are in
+the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
+on the files within that directory and not distract from the content with
+the extended "/sys/kernel/debug/tracing" path name.

 That's it! (assuming that you have ftrace configured into your kernel)

@@ -389,18 +401,18 @@ trace_options
 The trace_options file is used to control what gets printed in
 the trace output. To see what is available, simply cat the file:

-  cat /debug/tracing/trace_options
+  cat trace_options
   print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
   noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj

 To disable one of the options, echo in the option prepended with
 "no".

-  echo noprint-parent > /debug/tracing/trace_options
+  echo noprint-parent > trace_options

 To enable an option, leave off the "no".

-  echo sym-offset > /debug/tracing/trace_options
+  echo sym-offset > trace_options

 Here are the available options:

@@ -476,11 +488,11 @@ sched_switch
 This tracer simply records schedule switches. Here is an example
 of how to use it.

- # echo sched_switch > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo sched_switch > current_tracer
+ # echo 1 > tracing_enabled
  # sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace

 # tracer: sched_switch
 #
@@ -574,13 +586,13 @@ new trace is saved.
 To reset the maximum, echo 0 into tracing_max_latency. Here is
 an example:

- # echo irqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo irqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: irqsoff
 #
 irqsoff latency trace v1.1.5 on 2.6.26
@@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum
latency for
 which preemption was disabled. The control of preemptoff tracer
 is much like the irqsoff tracer.

- # echo preemptoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptoff
 #
 preemptoff latency trace v1.1.5 on 2.6.26-rc8
@@ -828,13 +840,13 @@ tracer.
 Again, using this trace is much like the irqsoff and preemptoff
 tracers.

- # echo preemptirqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptirqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptirqsoff
 #
 preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
@@ -990,12 +1002,12 @@ slightly differently than we did with the
previous tracers.
 Instead of performing an 'ls', we will run 'sleep 1' under
 'chrt' which changes the priority of the task.

- # echo wakeup > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo wakeup > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # chrt -f 5 sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: wakeup
 #
 wakeup latency trace v1.1.5 on 2.6.26-rc8
@@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
 ftrace_enabled is set; otherwise this tracer is a nop.

  # sysctl kernel.ftrace_enabled=1
- # echo function > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo function > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1146,7 +1158,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open(tracing_file("tracing_enabled"), O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1154,26 +1166,20 @@ int main(int argc, char *argv[]) {
 	[...]
 }

-Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
-/sys/kernel/debug). For simple one time traces, the above is
-sufficent. For anything else, a search through /proc/mounts may
-be needed to find where the debugfs file-system is mounted.
-

 Single thread tracing
 ---------------------

-By writing into /debug/tracing/set_ftrace_pid you can trace a
+By writing into set_ftrace_pid you can trace a
 single thread. For example:

-# cat /debug/tracing/set_ftrace_pid
+# cat set_ftrace_pid
 no pid
-# echo 3111 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/set_ftrace_pid
+# echo 3111 > set_ftrace_pid
+# cat set_ftrace_pid
 3111
-# echo function > /debug/tracing/current_tracer
-# cat /debug/tracing/trace | head
+# echo function > current_tracer
+# cat trace | head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1184,8 +1190,8 @@ no pid
      yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base
<-hrtimer_try_to_cancel
      yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
      yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
-# echo -1 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/trace |head
+# echo -1 > set_ftrace_pid
+# cat trace |head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1207,6 +1213,51 @@ something like this simple program:
 #include <fcntl.h>
 #include <unistd.h>

+#define _STR(x) #x
+#define STR(x) _STR(x)
+#define MAX_PATH 256
+
+const char *find_debugfs(void)
+{
+       static char debugfs[MAX_PATH+1];
+       static int debugfs_found;
+       char type[100];
+       FILE *fp;
+
+       if (debugfs_found)
+               return debugfs;
+
+       if ((fp = fopen("/proc/mounts","r")) == NULL) {
+               perror("/proc/mounts");
+               return NULL;
+       }
+
+       while (fscanf(fp, "%*s %"
+                     STR(MAX_PATH)
+                     "s %99s %*s %*d %*d\n",
+                     debugfs, type) == 2) {
+               if (strcmp(type, "debugfs") == 0)
+                       break;
+       }
+       fclose(fp);
+
+       if (strcmp(type, "debugfs") != 0) {
+               fprintf(stderr, "debugfs not mounted");
+               return NULL;
+       }
+
+       debugfs_found = 1;
+
+       return debugfs;
+}
+
+const char *tracing_file(const char *file_name)
+{
+       static char trace_file[MAX_PATH+1];
+       snprintf(trace_file, MAX_PATH, "%s/%s", find_debugfs(), file_name);
+       return trace_file;
+}
+
 int main (int argc, char **argv)
 {
         if (argc < 1)
@@ -1217,12 +1268,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;

-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd = open(tracing_file("current_tracer"), O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);

-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open(tracing_file("set_ftrace_pid"), O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);

@@ -1374,22 +1425,22 @@ want, depending on your needs.
   tracing_cpu_mask file) or you might sometimes see unordered
   function calls while cpu tracing switch.

-	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
-	show: echo funcgraph-cpu > /debug/tracing/trace_options
+	hide: echo nofuncgraph-cpu > trace_options
+	show: echo funcgraph-cpu > trace_options

 - The duration (function's time of execution) is displayed on
   the closing bracket line of a function or on the same line
   than the current function in case of a leaf one. It is default
   enabled.

-	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
-	show: echo funcgraph-duration > /debug/tracing/trace_options
+	hide: echo nofuncgraph-duration > trace_options
+	show: echo funcgraph-duration > trace_options

 - The overhead field precedes the duration field in case of
   reached duration thresholds.

-	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
-	show: echo funcgraph-overhead > /debug/tracing/trace_options
+	hide: echo nofuncgraph-overhead > trace_options
+	show: echo funcgraph-overhead > trace_options
 	depends on: funcgraph-duration

   ie:
@@ -1418,8 +1469,8 @@ want, depending on your needs.
 - The task/pid field displays the thread cmdline and pid which
   executed the function. It is default disabled.

-	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
-	show: echo funcgraph-proc > /debug/tracing/trace_options
+	hide: echo nofuncgraph-proc > trace_options
+	show: echo funcgraph-proc > trace_options

   ie:

@@ -1442,8 +1493,8 @@ want, depending on your needs.
   system clock since it started. A snapshot of this time is
   given on each entry/exit of functions

-	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
-	show: echo funcgraph-abstime > /debug/tracing/trace_options
+	hide: echo nofuncgraph-abstime > trace_options
+	show: echo funcgraph-abstime > trace_options

   ie:

@@ -1540,7 +1591,7 @@ listed in:

    available_filter_functions

- # cat /debug/tracing/available_filter_functions
+ # cat available_filter_functions
 put_prev_task_idle
 kmem_cache_create
 pick_next_task_rt
@@ -1552,12 +1603,12 @@ mutex_lock
 If I am only interested in sys_nanosleep and hrtimer_interrupt:

  # echo sys_nanosleep hrtimer_interrupt \
-		> /debug/tracing/set_ftrace_filter
- # echo ftrace > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+		> set_ftrace_filter
+ # echo ftrace > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: ftrace
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1568,7 +1619,7 @@ If I am only interested in sys_nanosleep and
hrtimer_interrupt:

 To see which functions are being traced, you can cat the file:

- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_interrupt
 sys_nanosleep

@@ -1588,7 +1639,7 @@ Note: It is better to use quotes to enclose the
wild cards,
       otherwise the shell may expand the parameters into names
       of files in the local directory.

- # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' > set_ftrace_filter

 Produces:

@@ -1609,7 +1660,7 @@ Produces:

 Notice that we lost the sys_nanosleep.

- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1635,17 +1686,17 @@ To append to the filters, use '>>'
 To clear out a filter so that all functions will be recorded
 again:

- # echo > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo > set_ftrace_filter
+ # cat set_ftrace_filter
  #

 Again, now we want to append.

- # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo sys_nanosleep > set_ftrace_filter
+ # cat set_ftrace_filter
 sys_nanosleep
- # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' >> set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1668,7 +1719,7 @@ hrtimer_init_sleeper
 The set_ftrace_notrace prevents those functions from being
 traced.

- # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+ # echo '*preempt*' '*lock*' > set_ftrace_notrace

 Produces:

@@ -1758,13 +1809,13 @@ the effect on the tracing is different. Every read from
 trace_pipe is consumed. This means that subsequent reads will be
 different. The trace is live.

- # echo function > /debug/tracing/current_tracer
- # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+ # echo function > current_tracer
+ # cat trace_pipe > /tmp/trace.out &
 [1] 4153
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1800,7 +1851,7 @@ number listed is the number of entries that can
be recorded per
 CPU. To know the full size, multiply the number of possible CPUS
 with the number of entries.

- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 1408 (units kilobytes)

 Note, to modify this, you must have tracing completely disabled.
@@ -1808,18 +1859,18 @@ To do that, echo "nop" into the current_tracer. If the
 current_tracer is not set to "nop", an EINVAL error will be
 returned.

- # echo nop > /debug/tracing/current_tracer
- # echo 10000 > /debug/tracing/buffer_size_kb
- # cat /debug/tracing/buffer_size_kb
+ # echo nop > current_tracer
+ # echo 10000 > buffer_size_kb
+ # cat buffer_size_kb
 10000 (units kilobytes)

 The number of pages which will be allocated is limited to a
 percentage of available memory. Allocating too much will produce
 an error.

- # echo 1000000000000 > /debug/tracing/buffer_size_kb
+ # echo 1000000000000 > buffer_size_kb
 -bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 85

---


-- 
Regards,
GeunSik Lim ( SAMSUNG ELECTRONICS)
Blog : http://blog.naver.com/invain/
e-Mail: geunsik.lim@samsung.com
           leemgs@gmail.com , leemgs1@gmail.com
--
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the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[RFC V3 PATCH]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

Dear Greg and Steven,

Thanks your advices and opinions about a confusion according to  
too many mount directory names for debugfs filesystem. 
I made rfc v3 like belows thanks to steven and greg.
Can I hear your advices and comments about below patch contents?  

* LKML about rfc v2: 
http://lkml.org/lkml/2009/5/29/219 

* LKML about rfc v1: 
http://lkml.org/lkml/2009/5/26/17 



Regards,
GeunSik Lim.


Subject: [PATCH] Fix terminology inconsistency of dir name to mount debugfs filesystem.

      Many developers use "/debug/" or "/debugfs/ directory name to mount
      debugfs filesystem for ftrace according to
      ./Documentation/tracers/ftrace.txt file.

      And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
      existed in kernel source like ftrace, DRM, Wireless, Documentation,
      Network[sky2]files to mount debugfs filesystem.

      debugfs means debug filesystem for debugging easy to use by greg kroah
      hartman. "/sys/kernel/debug/" name is suitable as directory name
      of debugfs filesystem.
      -debugfs related reference: http://lwn.net/Articles/334546/

      Fix inconsistency of directory name to mount debugfs filesystem.

        Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
        Acked-by     : Inaky Perez-Gonzalez <inaky@linux.intel.com>
        Reviewed-by  : Steven Rostedt <rostedt@goodmis.org>
        Reviewed-by  : Greg KH <greg@kroah.com>
        CC: Jiri Kosina <trivial@kernel.org>
        CC: David Airlie <airlied@linux.ie>
        CC: Peter Osterlund <petero2@telia.com>
        CC: James Smart <james.smart@emulex.com>
        CC: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
        CC: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
        CC: Masami Hiramatsu <mhiramat@redhat.com>
        CC: linux-kernel <linux-kernel@vger.kernel.org>
---
 Documentation/DocBook/debugobjects.tmpl           |    2 +-
 Documentation/cdrom/packet-writing.txt            |    2 +-
 Documentation/fault-injection/fault-injection.txt |   70 +++---
 Documentation/kprobes.txt                         |    6 +-
 Documentation/trace/ftrace.txt                    |  233 +++++++++++++--------
 Documentation/trace/mmiotrace.txt                 |   26 ++--
 drivers/block/pktcdvd.c                           |    2 +-
 drivers/gpu/drm/drm_debugfs.c                     |   12 +-
 drivers/gpu/drm/drm_drv.c                         |    2 +-
 drivers/gpu/drm/drm_stub.c                        |    2 +-
 drivers/net/Kconfig                               |    4 +-
 drivers/net/wimax/i2400m/i2400m.h                 |    2 +-
 drivers/net/wireless/ath5k/Kconfig                |    6 +-
 drivers/net/wireless/libertas/README              |   12 +-
 drivers/scsi/lpfc/lpfc_debugfs.c                  |    4 +-
 include/linux/kernel.h                            |    2 +-
 include/linux/tracepoint.h                        |    4 +-
 kernel/trace/Kconfig                              |   10 +-
 kernel/trace/trace.c                              |   24 +-
 scripts/tracing/draw_functrace.py                 |    8 +-
 20 files changed, 242 insertions(+), 191 deletions(-)

diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl
index 7f5f218..08ff908 100644
--- a/Documentation/DocBook/debugobjects.tmpl
+++ b/Documentation/DocBook/debugobjects.tmpl
@@ -106,7 +106,7 @@
       number of errors are printk'ed including a full stack trace.
     </para>
     <para>
-      The statistics are available via debugfs/debug_objects/stats.
+      The statistics are available via /sys/kernel/debug/debug_objects/stats.
       They provide information about the number of warnings and the
       number of successful fixups along with information about the
       usage of the internal tracking objects and the state of the
diff --git a/Documentation/cdrom/packet-writing.txt b/Documentation/cdrom/packet-writing.txt
index cf1f812..1c40777 100644
--- a/Documentation/cdrom/packet-writing.txt
+++ b/Documentation/cdrom/packet-writing.txt
@@ -117,7 +117,7 @@ Using the pktcdvd debugfs interface
 
 To read pktcdvd device infos in human readable form, do:
 
-	# cat /debug/pktcdvd/pktcdvd[0-7]/info
+	# cat /sys/kernel/debug/pktcdvd/pktcdvd[0-7]/info
 
 For a description of the debugfs interface look into the file:
 
diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt
index 4bc374a..0793056 100644
--- a/Documentation/fault-injection/fault-injection.txt
+++ b/Documentation/fault-injection/fault-injection.txt
@@ -29,16 +29,16 @@ o debugfs entries
 fault-inject-debugfs kernel module provides some debugfs entries for runtime
 configuration of fault-injection capabilities.
 
-- /debug/fail*/probability:
+- /sys/kernel/debug/fail*/probability:
 
 	likelihood of failure injection, in percent.
 	Format: <percent>
 
 	Note that one-failure-per-hundred is a very high error rate
 	for some testcases.  Consider setting probability=100 and configure
-	/debug/fail*/interval for such testcases.
+	/sys/kernel/debug/fail*/interval for such testcases.
 
-- /debug/fail*/interval:
+- /sys/kernel/debug/fail*/interval:
 
 	specifies the interval between failures, for calls to
 	should_fail() that pass all the other tests.
@@ -46,18 +46,18 @@ configuration of fault-injection capabilities.
 	Note that if you enable this, by setting interval>1, you will
 	probably want to set probability=100.
 
-- /debug/fail*/times:
+- /sys/kernel/debug/fail*/times:
 
 	specifies how many times failures may happen at most.
 	A value of -1 means "no limit".
 
-- /debug/fail*/space:
+- /sys/kernel/debug/fail*/space:
 
 	specifies an initial resource "budget", decremented by "size"
 	on each call to should_fail(,size).  Failure injection is
 	suppressed until "space" reaches zero.
 
-- /debug/fail*/verbose
+- /sys/kernel/debug/fail*/verbose
 
 	Format: { 0 | 1 | 2 }
 	specifies the verbosity of the messages when failure is
@@ -65,17 +65,17 @@ configuration of fault-injection capabilities.
 	log line per failure; '2' will print a call trace too -- useful
 	to debug the problems revealed by fault injection.
 
-- /debug/fail*/task-filter:
+- /sys/kernel/debug/fail*/task-filter:
 
 	Format: { 'Y' | 'N' }
 	A value of 'N' disables filtering by process (default).
 	Any positive value limits failures to only processes indicated by
 	/proc/<pid>/make-it-fail==1.
 
-- /debug/fail*/require-start:
-- /debug/fail*/require-end:
-- /debug/fail*/reject-start:
-- /debug/fail*/reject-end:
+- /sys/kernel/debug/fail*/require-start:
+- /sys/kernel/debug/fail*/require-end:
+- /sys/kernel/debug/fail*/reject-start:
+- /sys/kernel/debug/fail*/reject-end:
 
 	specifies the range of virtual addresses tested during
 	stacktrace walking.  Failure is injected only if some caller
@@ -84,26 +84,26 @@ configuration of fault-injection capabilities.
 	Default required range is [0,ULONG_MAX) (whole of virtual address space).
 	Default rejected range is [0,0).
 
-- /debug/fail*/stacktrace-depth:
+- /sys/kernel/debug/fail*/stacktrace-depth:
 
 	specifies the maximum stacktrace depth walked during search
 	for a caller within [require-start,require-end) OR
 	[reject-start,reject-end).
 
-- /debug/fail_page_alloc/ignore-gfp-highmem:
+- /sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:
 
 	Format: { 'Y' | 'N' }
 	default is 'N', setting it to 'Y' won't inject failures into
 	highmem/user allocations.
 
-- /debug/failslab/ignore-gfp-wait:
-- /debug/fail_page_alloc/ignore-gfp-wait:
+- /sys/kernel/debug/failslab/ignore-gfp-wait:
+- /sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:
 
 	Format: { 'Y' | 'N' }
 	default is 'N', setting it to 'Y' will inject failures
 	only into non-sleep allocations (GFP_ATOMIC allocations).
 
-- /debug/fail_page_alloc/min-order:
+- /sys/kernel/debug/fail_page_alloc/min-order:
 
 	specifies the minimum page allocation order to be injected
 	failures.
@@ -166,13 +166,13 @@ o Inject slab allocation failures into module init/exit code
 #!/bin/bash
 
 FAILTYPE=failslab
-echo Y > /debug/$FAILTYPE/task-filter
-echo 10 > /debug/$FAILTYPE/probability
-echo 100 > /debug/$FAILTYPE/interval
-echo -1 > /debug/$FAILTYPE/times
-echo 0 > /debug/$FAILTYPE/space
-echo 2 > /debug/$FAILTYPE/verbose
-echo 1 > /debug/$FAILTYPE/ignore-gfp-wait
+echo Y > /sys/kernel/debug/$FAILTYPE/task-filter
+echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+echo -1 > /sys/kernel/debug/$FAILTYPE/times
+echo 0 > /sys/kernel/debug/$FAILTYPE/space
+echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
 
 faulty_system()
 {
@@ -217,20 +217,20 @@ then
 	exit 1
 fi
 
-cat /sys/module/$module/sections/.text > /debug/$FAILTYPE/require-start
-cat /sys/module/$module/sections/.data > /debug/$FAILTYPE/require-end
+cat /sys/module/$module/sections/.text > /sys/kernel/debug/$FAILTYPE/require-start
+cat /sys/module/$module/sections/.data > /sys/kernel/debug/$FAILTYPE/require-end
 
-echo N > /debug/$FAILTYPE/task-filter
-echo 10 > /debug/$FAILTYPE/probability
-echo 100 > /debug/$FAILTYPE/interval
-echo -1 > /debug/$FAILTYPE/times
-echo 0 > /debug/$FAILTYPE/space
-echo 2 > /debug/$FAILTYPE/verbose
-echo 1 > /debug/$FAILTYPE/ignore-gfp-wait
-echo 1 > /debug/$FAILTYPE/ignore-gfp-highmem
-echo 10 > /debug/$FAILTYPE/stacktrace-depth
+echo N > /sys/kernel/debug/$FAILTYPE/task-filter
+echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+echo -1 > /sys/kernel/debug/$FAILTYPE/times
+echo 0 > /sys/kernel/debug/$FAILTYPE/space
+echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
+echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth
 
-trap "echo 0 > /debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
+trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
 
 echo "Injecting errors into the module $module... (interrupt to stop)"
 sleep 1000000
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt
index 1e7a769..053037a 100644
--- a/Documentation/kprobes.txt
+++ b/Documentation/kprobes.txt
@@ -507,9 +507,9 @@ http://www.linuxsymposium.org/2006/linuxsymposium_procv2.pdf (pages 101-115)
 Appendix A: The kprobes debugfs interface
 
 With recent kernels (> 2.6.20) the list of registered kprobes is visible
-under the /debug/kprobes/ directory (assuming debugfs is mounted at /debug).
+under the /sys/kernel/debug/kprobes/ directory (assuming debugfs is mounted at //sys/kernel/debug).
 
-/debug/kprobes/list: Lists all registered probes on the system
+/sys/kernel/debug/kprobes/list: Lists all registered probes on the system
 
 c015d71a  k  vfs_read+0x0
 c011a316  j  do_fork+0x0
@@ -525,7 +525,7 @@ virtual addresses that correspond to modules that've been unloaded),
 such probes are marked with [GONE]. If the probe is temporarily disabled,
 such probes are marked with [DISABLED].
 
-/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
+/sys/kernel/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
 
 Provides a knob to globally and forcibly turn registered kprobes ON or OFF.
 By default, all kprobes are enabled. By echoing "0" to this file, all
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..05f8378 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
                (dual licensed under the GPL v2)
 Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
 	     John Kacur, and David Teigland.
-
 Written for: 2.6.28-rc2
 
 Introduction
@@ -33,13 +32,26 @@ The File System
 Ftrace uses the debugfs file system to hold the control files as
 well as the files to display output.
 
-To mount the debugfs system:
+When debugfs is configured into the kernel (which selecting any ftrace
+option will do) the directory /sys/kernel/debug will be created. To mount
+this directory, you can add to your /etc/fstab file:
+
+ debugfs       /sys/kernel/debug          debugfs defaults        0       0
+
+Or you can mount it at run time with:
+
+ mount -t debugfs nodev /sys/kernel/debug
 
-  # mkdir /debug
-  # mount -t debugfs nodev /debug
+For quicker access to that directory you may want to make a soft link to
+it:
 
-( Note: it is more common to mount at /sys/kernel/debug, but for
-  simplicity this document will use /debug)
+ ln -s /sys/kernel/debug /debug
+
+Any selected ftrace option will also create a directory called tracing
+within the debugfs. The rest of the document will assume that you are in
+the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
+on the files within that directory and not distract from the content with
+the extended "/sys/kernel/debug/tracing" path name.
 
 That's it! (assuming that you have ftrace configured into your kernel)
 
@@ -389,18 +401,18 @@ trace_options
 The trace_options file is used to control what gets printed in
 the trace output. To see what is available, simply cat the file:
 
-  cat /debug/tracing/trace_options
+  cat trace_options
   print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
   noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj
 
 To disable one of the options, echo in the option prepended with
 "no".
 
-  echo noprint-parent > /debug/tracing/trace_options
+  echo noprint-parent > trace_options
 
 To enable an option, leave off the "no".
 
-  echo sym-offset > /debug/tracing/trace_options
+  echo sym-offset > trace_options
 
 Here are the available options:
 
@@ -476,11 +488,11 @@ sched_switch
 This tracer simply records schedule switches. Here is an example
 of how to use it.
 
- # echo sched_switch > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo sched_switch > current_tracer
+ # echo 1 > tracing_enabled
  # sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 
 # tracer: sched_switch
 #
@@ -574,13 +586,13 @@ new trace is saved.
 To reset the maximum, echo 0 into tracing_max_latency. Here is
 an example:
 
- # echo irqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo irqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: irqsoff
 #
 irqsoff latency trace v1.1.5 on 2.6.26
@@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum latency for
 which preemption was disabled. The control of preemptoff tracer
 is much like the irqsoff tracer.
 
- # echo preemptoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptoff
 #
 preemptoff latency trace v1.1.5 on 2.6.26-rc8
@@ -828,13 +840,13 @@ tracer.
 Again, using this trace is much like the irqsoff and preemptoff
 tracers.
 
- # echo preemptirqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptirqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptirqsoff
 #
 preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
@@ -990,12 +1002,12 @@ slightly differently than we did with the previous tracers.
 Instead of performing an 'ls', we will run 'sleep 1' under
 'chrt' which changes the priority of the task.
 
- # echo wakeup > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo wakeup > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # chrt -f 5 sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: wakeup
 #
 wakeup latency trace v1.1.5 on 2.6.26-rc8
@@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
 ftrace_enabled is set; otherwise this tracer is a nop.
 
  # sysctl kernel.ftrace_enabled=1
- # echo function > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo function > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1146,7 +1158,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open(tracing_file("tracing_enabled"), O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1154,26 +1166,20 @@ int main(int argc, char *argv[]) {
 	[...]
 }
 
-Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
-/sys/kernel/debug). For simple one time traces, the above is
-sufficent. For anything else, a search through /proc/mounts may
-be needed to find where the debugfs file-system is mounted.
-
 
 Single thread tracing
 ---------------------
 
-By writing into /debug/tracing/set_ftrace_pid you can trace a
+By writing into set_ftrace_pid you can trace a
 single thread. For example:
 
-# cat /debug/tracing/set_ftrace_pid
+# cat set_ftrace_pid
 no pid
-# echo 3111 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/set_ftrace_pid
+# echo 3111 > set_ftrace_pid
+# cat set_ftrace_pid
 3111
-# echo function > /debug/tracing/current_tracer
-# cat /debug/tracing/trace | head
+# echo function > current_tracer
+# cat trace | head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1184,8 +1190,8 @@ no pid
      yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base <-hrtimer_try_to_cancel
      yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
      yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
-# echo -1 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/trace |head
+# echo -1 > set_ftrace_pid
+# cat trace |head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1207,6 +1213,51 @@ something like this simple program:
 #include <fcntl.h>
 #include <unistd.h>
 
+#define _STR(x) #x
+#define STR(x) _STR(x)
+#define MAX_PATH 256
+
+const char *find_debugfs(void)
+{
+       static char debugfs[MAX_PATH+1];
+       static int debugfs_found;
+       char type[100];
+       FILE *fp;
+ 
+       if (debugfs_found)
+               return debugfs;
+
+       if ((fp = fopen("/proc/mounts","r")) == NULL) {
+               perror("/proc/mounts");
+               return NULL;
+       }
+
+       while (fscanf(fp, "%*s %"
+                     STR(MAX_PATH)
+                     "s %99s %*s %*d %*d\n",
+                     debugfs, type) == 2) {
+               if (strcmp(type, "debugfs") == 0)
+                       break;
+       }
+       fclose(fp);
+
+       if (strcmp(type, "debugfs") != 0) {
+               fprintf(stderr, "debugfs not mounted");
+               return NULL;
+       }
+
+       debugfs_found = 1;
+
+       return debugfs;
+}
+
+const char *tracing_file(const char *file_name)
+{
+       static char trace_file[MAX_PATH+1];
+       snprintf(trace_file, MAX_PATH, "%s/%s", find_debugfs(), file_name);
+       return trace_file;
+}
+
 int main (int argc, char **argv)
 {
         if (argc < 1)
@@ -1217,12 +1268,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;
 
-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd = open(tracing_file("current_tracer"), O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);
 
-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open(tracing_file("set_ftrace_pid"), O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);
 
@@ -1374,22 +1425,22 @@ want, depending on your needs.
   tracing_cpu_mask file) or you might sometimes see unordered
   function calls while cpu tracing switch.
 
-	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
-	show: echo funcgraph-cpu > /debug/tracing/trace_options
+	hide: echo nofuncgraph-cpu > trace_options
+	show: echo funcgraph-cpu > trace_options
 
 - The duration (function's time of execution) is displayed on
   the closing bracket line of a function or on the same line
   than the current function in case of a leaf one. It is default
   enabled.
 
-	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
-	show: echo funcgraph-duration > /debug/tracing/trace_options
+	hide: echo nofuncgraph-duration > trace_options
+	show: echo funcgraph-duration > trace_options
 
 - The overhead field precedes the duration field in case of
   reached duration thresholds.
 
-	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
-	show: echo funcgraph-overhead > /debug/tracing/trace_options
+	hide: echo nofuncgraph-overhead > trace_options
+	show: echo funcgraph-overhead > trace_options
 	depends on: funcgraph-duration
 
   ie:
@@ -1418,8 +1469,8 @@ want, depending on your needs.
 - The task/pid field displays the thread cmdline and pid which
   executed the function. It is default disabled.
 
-	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
-	show: echo funcgraph-proc > /debug/tracing/trace_options
+	hide: echo nofuncgraph-proc > trace_options
+	show: echo funcgraph-proc > trace_options
 
   ie:
 
@@ -1442,8 +1493,8 @@ want, depending on your needs.
   system clock since it started. A snapshot of this time is
   given on each entry/exit of functions
 
-	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
-	show: echo funcgraph-abstime > /debug/tracing/trace_options
+	hide: echo nofuncgraph-abstime > trace_options
+	show: echo funcgraph-abstime > trace_options
 
   ie:
 
@@ -1540,7 +1591,7 @@ listed in:
 
    available_filter_functions
 
- # cat /debug/tracing/available_filter_functions
+ # cat available_filter_functions
 put_prev_task_idle
 kmem_cache_create
 pick_next_task_rt
@@ -1552,12 +1603,12 @@ mutex_lock
 If I am only interested in sys_nanosleep and hrtimer_interrupt:
 
  # echo sys_nanosleep hrtimer_interrupt \
-		> /debug/tracing/set_ftrace_filter
- # echo ftrace > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+		> set_ftrace_filter
+ # echo ftrace > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: ftrace
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1568,7 +1619,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt:
 
 To see which functions are being traced, you can cat the file:
 
- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_interrupt
 sys_nanosleep
 
@@ -1588,7 +1639,7 @@ Note: It is better to use quotes to enclose the wild cards,
       otherwise the shell may expand the parameters into names
       of files in the local directory.
 
- # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' > set_ftrace_filter
 
 Produces:
 
@@ -1609,7 +1660,7 @@ Produces:
 
 Notice that we lost the sys_nanosleep.
 
- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1635,17 +1686,17 @@ To append to the filters, use '>>'
 To clear out a filter so that all functions will be recorded
 again:
 
- # echo > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo > set_ftrace_filter
+ # cat set_ftrace_filter
  #
 
 Again, now we want to append.
 
- # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo sys_nanosleep > set_ftrace_filter
+ # cat set_ftrace_filter
 sys_nanosleep
- # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' >> set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1668,7 +1719,7 @@ hrtimer_init_sleeper
 The set_ftrace_notrace prevents those functions from being
 traced.
 
- # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+ # echo '*preempt*' '*lock*' > set_ftrace_notrace
 
 Produces:
 
@@ -1758,13 +1809,13 @@ the effect on the tracing is different. Every read from
 trace_pipe is consumed. This means that subsequent reads will be
 different. The trace is live.
 
- # echo function > /debug/tracing/current_tracer
- # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+ # echo function > current_tracer
+ # cat trace_pipe > /tmp/trace.out &
 [1] 4153
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1800,7 +1851,7 @@ number listed is the number of entries that can be recorded per
 CPU. To know the full size, multiply the number of possible CPUS
 with the number of entries.
 
- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 1408 (units kilobytes)
 
 Note, to modify this, you must have tracing completely disabled.
@@ -1808,18 +1859,18 @@ To do that, echo "nop" into the current_tracer. If the
 current_tracer is not set to "nop", an EINVAL error will be
 returned.
 
- # echo nop > /debug/tracing/current_tracer
- # echo 10000 > /debug/tracing/buffer_size_kb
- # cat /debug/tracing/buffer_size_kb
+ # echo nop > current_tracer
+ # echo 10000 > buffer_size_kb
+ # cat buffer_size_kb
 10000 (units kilobytes)
 
 The number of pages which will be allocated is limited to a
 percentage of available memory. Allocating too much will produce
 an error.
 
- # echo 1000000000000 > /debug/tracing/buffer_size_kb
+ # echo 1000000000000 > buffer_size_kb
 -bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 85
 
 -----------
diff --git a/Documentation/trace/mmiotrace.txt b/Documentation/trace/mmiotrace.txt
index 5731c67..162effb 100644
--- a/Documentation/trace/mmiotrace.txt
+++ b/Documentation/trace/mmiotrace.txt
@@ -32,41 +32,41 @@ is no way to automatically detect if you are losing events due to CPUs racing.
 Usage Quick Reference
 ---------------------
 
-$ mount -t debugfs debugfs /debug
-$ echo mmiotrace > /debug/tracing/current_tracer
-$ cat /debug/tracing/trace_pipe > mydump.txt &
+$ mount -t debugfs debugfs /sys/kernel/debug
+$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
+$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
 Start X or whatever.
-$ echo "X is up" > /debug/tracing/trace_marker
-$ echo nop > /debug/tracing/current_tracer
+$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
+$ echo nop > /sys/kernel/debug/tracing/current_tracer
 Check for lost events.
 
 
 Usage
 -----
 
-Make sure debugfs is mounted to /debug. If not, (requires root privileges)
-$ mount -t debugfs debugfs /debug
+Make sure debugfs is mounted to /sys/kernel/debug. If not, (requires root privileges)
+$ mount -t debugfs debugfs /sys/kernel/debug
 
 Check that the driver you are about to trace is not loaded.
 
 Activate mmiotrace (requires root privileges):
-$ echo mmiotrace > /debug/tracing/current_tracer
+$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
 
 Start storing the trace:
-$ cat /debug/tracing/trace_pipe > mydump.txt &
+$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
 The 'cat' process should stay running (sleeping) in the background.
 
 Load the driver you want to trace and use it. Mmiotrace will only catch MMIO
 accesses to areas that are ioremapped while mmiotrace is active.
 
 During tracing you can place comments (markers) into the trace by
-$ echo "X is up" > /debug/tracing/trace_marker
+$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
 This makes it easier to see which part of the (huge) trace corresponds to
 which action. It is recommended to place descriptive markers about what you
 do.
 
 Shut down mmiotrace (requires root privileges):
-$ echo nop > /debug/tracing/current_tracer
+$ echo nop > /sys/kernel/debug/tracing/current_tracer
 The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
 pressing ctrl+c.
 
@@ -78,10 +78,10 @@ to view your kernel log and look for "mmiotrace has lost events" warning. If
 events were lost, the trace is incomplete. You should enlarge the buffers and
 try again. Buffers are enlarged by first seeing how large the current buffers
 are:
-$ cat /debug/tracing/buffer_size_kb
+$ cat /sys/kernel/debug/tracing/buffer_size_kb
 gives you a number. Approximately double this number and write it back, for
 instance:
-$ echo 128000 > /debug/tracing/buffer_size_kb
+$ echo 128000 > /sys/kernel/debug/tracing/buffer_size_kb
 Then start again from the top.
 
 If you are doing a trace for a driver project, e.g. Nouveau, you should also
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index dc7a8c3..9aa8932 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -430,7 +430,7 @@ static void pkt_sysfs_cleanup(void)
 /********************************************************************
   entries in debugfs
 
-  /debugfs/pktcdvd[0-7]/
+  /sys/kernel/debug/pktcdvd[0-7]/
 			info
 
  *******************************************************************/
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index c77c6c6..6ce0e26 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -105,7 +105,7 @@ int drm_debugfs_create_files(struct drm_info_list *files, int count,
 		ent = debugfs_create_file(files[i].name, S_IFREG | S_IRUGO,
 					  root, tmp, &drm_debugfs_fops);
 		if (!ent) {
-			DRM_ERROR("Cannot create /debugfs/dri/%s/%s\n",
+			DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s/%s\n",
 				  name, files[i].name);
 			drm_free(tmp, sizeof(struct drm_info_node),
 				 _DRM_DRIVER);
@@ -133,9 +133,9 @@ EXPORT_SYMBOL(drm_debugfs_create_files);
  * \param minor device minor number
  * \param root DRI debugfs dir entry.
  *
- * Create the DRI debugfs root entry "/debugfs/dri", the device debugfs root entry
- * "/debugfs/dri/%minor%/", and each entry in debugfs_list as
- * "/debugfs/dri/%minor%/%name%".
+ * Create the DRI debugfs root entry "/sys/kernel/debug/dri", the device debugfs root entry
+ * "/sys/kernel/debug/dri/%minor%/", and each entry in debugfs_list as
+ * "/sys/kernel/debug/dri/%minor%/%name%".
  */
 int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		     struct dentry *root)
@@ -148,7 +148,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 	sprintf(name, "%d", minor_id);
 	minor->debugfs_root = debugfs_create_dir(name, root);
 	if (!minor->debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri/%s\n", name);
+		DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s\n", name);
 		return -1;
 	}
 
@@ -165,7 +165,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		ret = dev->driver->debugfs_init(minor);
 		if (ret) {
 			DRM_ERROR("DRM: Driver failed to initialize "
-				  "/debugfs/dri.\n");
+				  "/sys/kernel/debug/dri.\n");
 			return ret;
 		}
 	}
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 019b7c5..1bf7efd 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -339,7 +339,7 @@ static int __init drm_core_init(void)
 
 	drm_debugfs_root = debugfs_create_dir("dri", NULL);
 	if (!drm_debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri\n");
+		DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
 		ret = -1;
 		goto err_p3;
 	}
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index b9631e3..b2a93c4 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -328,7 +328,7 @@ static int drm_get_minor(struct drm_device *dev, struct drm_minor **minor, int t
 #if defined(CONFIG_DEBUG_FS)
 	ret = drm_debugfs_init(new_minor, minor_id, drm_debugfs_root);
 	if (ret) {
-		DRM_ERROR("DRM: Failed to initialize /debugfs/dri.\n");
+		DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
 		goto err_g2;
 	}
 #endif
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 214a92d..a170cea 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2200,7 +2200,7 @@ config SKGE_DEBUG
        depends on SKGE && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/skge/ethX displays the state of the internal
+	 The file /sys/kernel/debug/skge/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
@@ -2226,7 +2226,7 @@ config SKY2_DEBUG
        depends on SKY2 && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/sky2/ethX displays the state of the internal
+	 The file /sys/kernel/debug/sky2/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
diff --git a/drivers/net/wimax/i2400m/i2400m.h b/drivers/net/wimax/i2400m/i2400m.h
index 3ae2df3..da2e8f2 100644
--- a/drivers/net/wimax/i2400m/i2400m.h
+++ b/drivers/net/wimax/i2400m/i2400m.h
@@ -389,7 +389,7 @@ struct i2400m {
 	unsigned ready:1;		/* all probing steps done */
 	unsigned rx_reorder:1;		/* RX reorder is enabled */
 	u8 trace_msg_from_user;		/* echo rx msgs to 'trace' pipe */
-					/* typed u8 so debugfs/u8 can tweak */
+					/* typed u8 so /sys/kernel/debug/u8 can tweak */
 	enum i2400m_system_state state;
 	wait_queue_head_t state_wq;	/* Woken up when on state updates */
 
diff --git a/drivers/net/wireless/ath5k/Kconfig b/drivers/net/wireless/ath5k/Kconfig
index 75383a5..fdfa708 100644
--- a/drivers/net/wireless/ath5k/Kconfig
+++ b/drivers/net/wireless/ath5k/Kconfig
@@ -27,11 +27,11 @@ config ATH5K_DEBUG
 	  Say Y, if and you will get debug options for ath5k.
 	  To use this, you need to mount debugfs:
 
-	  mkdir /debug/
-	  mount -t debugfs debug /debug/
+	  mkdir /sys/kernel/debug/
+	  mount -t debugfs debug /sys/kernel/debug/
 
 	  You will get access to files under:
-	  /debug/ath5k/phy0/
+	  /sys/kernel/debug/ath5k/phy0/
 
 	  To enable debug, pass the debug level to the debug module
 	  parameter. For example:
diff --git a/drivers/net/wireless/libertas/README b/drivers/net/wireless/libertas/README
index d860fc3..ab6a2d5 100644
--- a/drivers/net/wireless/libertas/README
+++ b/drivers/net/wireless/libertas/README
@@ -72,7 +72,7 @@ rdrf
 	location that is to be read.  This parameter must be specified in
 	hexadecimal (its possible to preceed preceding the number with a "0x").
 
-	Path: /debugfs/libertas_wireless/ethX/registers/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/registers/
 
 	Usage:
 		echo "0xa123" > rdmac ; cat rdmac
@@ -95,7 +95,7 @@ wrrf
 sleepparams
 	This command is used to set the sleepclock configurations
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage:
 		cat sleepparams: reads the current sleepclock configuration
@@ -115,7 +115,7 @@ subscribed_events
 	The subscribed_events directory contains the interface for the
 	subscribed events API.
 
-	Path: /debugfs/libertas_wireless/ethX/subscribed_events/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/subscribed_events/
 
 	Each event is represented by a filename. Each filename consists of the
 	following three fields:
@@ -165,7 +165,7 @@ subscribed_events
 extscan
 	This command is used to do a specific scan.
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage: echo "SSID" > extscan
 
@@ -179,7 +179,7 @@ getscantable
 	Display the current contents of the driver scan table (ie. get the
 	scan results).
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage:
 		cat getscantable
@@ -188,7 +188,7 @@ setuserscan
 	Initiate a customized scan and retrieve the results
 
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
     Usage:
        echo "[ARGS]" > setuserscan
diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index 52be564..9112380 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -51,8 +51,8 @@
  * debugfs interface
  *
  * To access this interface the user should:
- * # mkdir /debug
- * # mount -t debugfs none /debug
+ * # mkdir /sys/kernel/debug
+ * # mount -t debugfs none /sys/kernel/debug
  *
  * The lpfc debugfs directory hierarchy is:
  * lpfc/lpfcX/vportY
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 883cd44..99b7aad 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -406,7 +406,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
  *
  * Use tracing_on/tracing_off when you want to quickly turn on or off
  * tracing. It simply enables or disables the recording of the trace events.
- * This also corresponds to the user space debugfs/tracing/tracing_on
+ * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
  * file, which gives a means for the kernel and userspace to interact.
  * Place a tracing_off() in the kernel where you want tracing to end.
  * From user space, examine the trace, and then echo 1 > tracing_on
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index d35a7ee..9c9ac7d 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -197,7 +197,7 @@ static inline void tracepoint_synchronize_unregister(void)
  *	* This is how the trace record is structured and will
  *	* be saved into the ring buffer. These are the fields
  *	* that will be exposed to user-space in
- *	* /debug/tracing/events/<*>/format.
+ *	* /sys/kernel/debug/tracing/events/<*>/format.
  *	*
  *	* The declared 'local variable' is called '__entry'
  *	*
@@ -257,7 +257,7 @@ static inline void tracepoint_synchronize_unregister(void)
  * tracepoint callback (this is used by programmatic plugins and
  * can also by used by generic instrumentation like SystemTap), and
  * it is also used to expose a structured trace record in
- * /debug/tracing/events/.
+ * /sys/kernel/debug/tracing/events/.
  */
 
 #define TRACE_EVENT(name, proto, args, struct, assign, print)	\
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 417d198..e5ce28f 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -120,7 +120,7 @@ config IRQSOFF_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the preempt-off timing option can be
@@ -141,7 +141,7 @@ config PREEMPT_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the irqs-off timing option can be
@@ -213,7 +213,7 @@ config TRACE_BRANCH_PROFILING
 	  This tracer profiles all the the likely and unlikely macros
 	  in the kernel. It will display the results in:
 
-	  /debugfs/tracing/profile_annotated_branch
+	  /sys/kernel/debug/tracing/profile_annotated_branch
 
 	  Note: this will add a significant overhead, only turn this
 	  on if you need to profile the system's use of these macros.
@@ -228,7 +228,7 @@ config PROFILE_ALL_BRANCHES
 	  taken in the kernel is recorded whether it hit or miss.
 	  The results will be displayed in:
 
-	  /debugfs/tracing/profile_branch
+	  /sys/kernel/debug/tracing/profile_branch
 
 	  This configuration, when enabled, will impose a great overhead
 	  on the system. This should only be enabled when the system
@@ -276,7 +276,7 @@ config STACK_TRACER
 	select KALLSYMS
 	help
 	  This special tracer records the maximum stack footprint of the
-	  kernel and displays it in debugfs/tracing/stack_trace.
+	  kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
 
 	  This tracer works by hooking into every function call that the
 	  kernel executes, and keeping a maximum stack depth value and
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index cda81ec..9b94d57 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -335,7 +335,7 @@ static raw_spinlock_t ftrace_max_lock =
 /*
  * Copy the new maximum trace into the separate maximum-trace
  * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /debugfs/tracing/latency_trace)
+ * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
  */
 static void
 __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
@@ -2366,21 +2366,21 @@ static const struct file_operations tracing_iter_fops = {
 
 static const char readme_msg[] =
 	"tracing mini-HOWTO:\n\n"
-	"# mkdir /debug\n"
-	"# mount -t debugfs nodev /debug\n\n"
-	"# cat /debug/tracing/available_tracers\n"
+	"# mkdir /sys/kernel/debug\n"
+	"# mount -t debugfs nodev /sys/kernel/debug\n\n"
+	"# cat /sys/kernel/debug/tracing/available_tracers\n"
 	"wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
-	"# cat /debug/tracing/current_tracer\n"
+	"# cat /sys/kernel/debug/tracing/current_tracer\n"
 	"nop\n"
-	"# echo sched_switch > /debug/tracing/current_tracer\n"
-	"# cat /debug/tracing/current_tracer\n"
+	"# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
+	"# cat /sys/kernel/debug/tracing/current_tracer\n"
 	"sched_switch\n"
-	"# cat /debug/tracing/trace_options\n"
+	"# cat /sys/kernel/debug/tracing/trace_options\n"
 	"noprint-parent nosym-offset nosym-addr noverbose\n"
-	"# echo print-parent > /debug/tracing/trace_options\n"
-	"# echo 1 > /debug/tracing/tracing_enabled\n"
-	"# cat /debug/tracing/trace > /tmp/trace.txt\n"
-	"# echo 0 > /debug/tracing/tracing_enabled\n"
+	"# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
+	"# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
+	"# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
+	"# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
 ;
 
 static ssize_t
diff --git a/scripts/tracing/draw_functrace.py b/scripts/tracing/draw_functrace.py
index 902f9a9..66f4d1b 100644
--- a/scripts/tracing/draw_functrace.py
+++ b/scripts/tracing/draw_functrace.py
@@ -12,10 +12,10 @@ calls. Only the functions's names and the the call time are provided.
 
 Usage:
 	Be sure that you have CONFIG_FUNCTION_TRACER
-	# mkdir /debugfs
-	# mount -t debug debug /debug
-	# echo function > /debug/tracing/current_tracer
-	$ cat /debug/tracing/trace_pipe > ~/raw_trace_func
+	# mkdir /sys/kernel/debug
+	# mount -t debug debug /sys/kernel/debug
+	# echo function > /sys/kernel/debug/tracing/current_tracer
+	$ cat /sys/kernel/debug/tracing/trace_pipe > ~/raw_trace_func
 	Wait some times but not too much, the script is a bit slow.
 	Break the pipe (Ctrl + Z)
 	$ scripts/draw_functrace.py < raw_trace_func > draw_functrace
-- 
1.6.3.1




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GeunSik Lim (  S A M S U N G     E L E C T R O N I C S  )
e-Mail  :1) geunsik.lim@samsung.com
         2) leemgs@gmail.com , leemgs1@gmail.com
HomePage: http://blog.naver.com/invain/
-----------------------------------------------

[PATCH V1]debugfs:Fix terminology inconsistency of dir name to mount debugfs filesystem.

[GeunSik Lim]

Dear Greg and Steven,

This is debugfs's mount directory related patch files. 
Please, merge my patch. Any Comment?

I read ./linux-2.6.git/MAINTAINERS file to submit debugfs related this patch file. 
But, I don't know a maintainer about this patch exactly.
Um...  If I mistake, Please, correct me.  


Thanks,





Subject: [PATCH V1] Fix terminology inconsistency of dir name to mount debugfs filesystem.

      Many developers use "/debug/" or "/debugfs/" or "/sys/kernel/debug/"
      directory name to mount debugfs filesystem for ftrace according to
      ./Documentation/tracers/ftrace.txt file.

      And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
      existed in kernel source like ftrace, DRM, Wireless, Documentation,
      Network[sky2]files to mount debugfs filesystem.

      debugfs means debug filesystem for debugging easy to use by greg kroah
      hartman. "/sys/kernel/debug/" name is suitable as directory name
      of debugfs filesystem.
      - debugfs related reference: http://lwn.net/Articles/334546/

      Fix inconsistency of directory name to mount debugfs filesystem.
 
      * From Steven Rostedt
        - find_debugfs() and tracing_files() in this patch.

        Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
        Acked-by     : Inaky Perez-Gonzalez <inaky@linux.intel.com>
        Reviewed-by  : Steven Rostedt <rostedt@goodmis.org>
        Reviewed-by  : Greg KH <greg@kroah.com>
        Reviewed-by  : James Smart <james.smart@emulex.com>
        CC: Jiri Kosina <trivial@kernel.org>
        CC: David Airlie <airlied@linux.ie>
        CC: Peter Osterlund <petero2@telia.com>
        CC: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
        CC: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
        CC: Masami Hiramatsu <mhiramat@redhat.com>
        CC: linux-kernel <linux-kernel@vger.kernel.org>
---
 Documentation/DocBook/debugobjects.tmpl           |    2 +-
 Documentation/cdrom/packet-writing.txt            |    2 +-
 Documentation/fault-injection/fault-injection.txt |   70 +++---
 Documentation/kprobes.txt                         |    6 +-
 Documentation/trace/ftrace.txt                    |  233 +++++++++++++--------
 Documentation/trace/mmiotrace.txt                 |   26 ++--
 drivers/block/pktcdvd.c                           |    2 +-
 drivers/gpu/drm/drm_debugfs.c                     |   12 +-
 drivers/gpu/drm/drm_drv.c                         |    2 +-
 drivers/gpu/drm/drm_stub.c                        |    2 +-
 drivers/net/Kconfig                               |    4 +-
 drivers/net/wimax/i2400m/i2400m.h                 |    2 +-
 drivers/net/wireless/ath5k/Kconfig                |    6 +-
 drivers/net/wireless/libertas/README              |   12 +-
 drivers/scsi/lpfc/lpfc_debugfs.c                  |    4 +-
 include/linux/kernel.h                            |    2 +-
 include/linux/tracepoint.h                        |    4 +-
 kernel/trace/Kconfig                              |   10 +-
 kernel/trace/trace.c                              |   24 +-
 scripts/tracing/draw_functrace.py                 |    8 +-
 20 files changed, 242 insertions(+), 191 deletions(-)

diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl
index 7f5f218..08ff908 100644
--- a/Documentation/DocBook/debugobjects.tmpl
+++ b/Documentation/DocBook/debugobjects.tmpl
@@ -106,7 +106,7 @@
       number of errors are printk'ed including a full stack trace.
     </para>
     <para>
-      The statistics are available via debugfs/debug_objects/stats.
+      The statistics are available via /sys/kernel/debug/debug_objects/stats.
       They provide information about the number of warnings and the
       number of successful fixups along with information about the
       usage of the internal tracking objects and the state of the
diff --git a/Documentation/cdrom/packet-writing.txt b/Documentation/cdrom/packet-writing.txt
index cf1f812..1c40777 100644
--- a/Documentation/cdrom/packet-writing.txt
+++ b/Documentation/cdrom/packet-writing.txt
@@ -117,7 +117,7 @@ Using the pktcdvd debugfs interface
 
 To read pktcdvd device infos in human readable form, do:
 
-	# cat /debug/pktcdvd/pktcdvd[0-7]/info
+	# cat /sys/kernel/debug/pktcdvd/pktcdvd[0-7]/info
 
 For a description of the debugfs interface look into the file:
 
diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt
index 4bc374a..0793056 100644
--- a/Documentation/fault-injection/fault-injection.txt
+++ b/Documentation/fault-injection/fault-injection.txt
@@ -29,16 +29,16 @@ o debugfs entries
 fault-inject-debugfs kernel module provides some debugfs entries for runtime
 configuration of fault-injection capabilities.
 
-- /debug/fail*/probability:
+- /sys/kernel/debug/fail*/probability:
 
 	likelihood of failure injection, in percent.
 	Format: <percent>
 
 	Note that one-failure-per-hundred is a very high error rate
 	for some testcases.  Consider setting probability=100 and configure
-	/debug/fail*/interval for such testcases.
+	/sys/kernel/debug/fail*/interval for such testcases.
 
-- /debug/fail*/interval:
+- /sys/kernel/debug/fail*/interval:
 
 	specifies the interval between failures, for calls to
 	should_fail() that pass all the other tests.
@@ -46,18 +46,18 @@ configuration of fault-injection capabilities.
 	Note that if you enable this, by setting interval>1, you will
 	probably want to set probability=100.
 
-- /debug/fail*/times:
+- /sys/kernel/debug/fail*/times:
 
 	specifies how many times failures may happen at most.
 	A value of -1 means "no limit".
 
-- /debug/fail*/space:
+- /sys/kernel/debug/fail*/space:
 
 	specifies an initial resource "budget", decremented by "size"
 	on each call to should_fail(,size).  Failure injection is
 	suppressed until "space" reaches zero.
 
-- /debug/fail*/verbose
+- /sys/kernel/debug/fail*/verbose
 
 	Format: { 0 | 1 | 2 }
 	specifies the verbosity of the messages when failure is
@@ -65,17 +65,17 @@ configuration of fault-injection capabilities.
 	log line per failure; '2' will print a call trace too -- useful
 	to debug the problems revealed by fault injection.
 
-- /debug/fail*/task-filter:
+- /sys/kernel/debug/fail*/task-filter:
 
 	Format: { 'Y' | 'N' }
 	A value of 'N' disables filtering by process (default).
 	Any positive value limits failures to only processes indicated by
 	/proc/<pid>/make-it-fail==1.
 
-- /debug/fail*/require-start:
-- /debug/fail*/require-end:
-- /debug/fail*/reject-start:
-- /debug/fail*/reject-end:
+- /sys/kernel/debug/fail*/require-start:
+- /sys/kernel/debug/fail*/require-end:
+- /sys/kernel/debug/fail*/reject-start:
+- /sys/kernel/debug/fail*/reject-end:
 
 	specifies the range of virtual addresses tested during
 	stacktrace walking.  Failure is injected only if some caller
@@ -84,26 +84,26 @@ configuration of fault-injection capabilities.
 	Default required range is [0,ULONG_MAX) (whole of virtual address space).
 	Default rejected range is [0,0).
 
-- /debug/fail*/stacktrace-depth:
+- /sys/kernel/debug/fail*/stacktrace-depth:
 
 	specifies the maximum stacktrace depth walked during search
 	for a caller within [require-start,require-end) OR
 	[reject-start,reject-end).
 
-- /debug/fail_page_alloc/ignore-gfp-highmem:
+- /sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:
 
 	Format: { 'Y' | 'N' }
 	default is 'N', setting it to 'Y' won't inject failures into
 	highmem/user allocations.
 
-- /debug/failslab/ignore-gfp-wait:
-- /debug/fail_page_alloc/ignore-gfp-wait:
+- /sys/kernel/debug/failslab/ignore-gfp-wait:
+- /sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:
 
 	Format: { 'Y' | 'N' }
 	default is 'N', setting it to 'Y' will inject failures
 	only into non-sleep allocations (GFP_ATOMIC allocations).
 
-- /debug/fail_page_alloc/min-order:
+- /sys/kernel/debug/fail_page_alloc/min-order:
 
 	specifies the minimum page allocation order to be injected
 	failures.
@@ -166,13 +166,13 @@ o Inject slab allocation failures into module init/exit code
 #!/bin/bash
 
 FAILTYPE=failslab
-echo Y > /debug/$FAILTYPE/task-filter
-echo 10 > /debug/$FAILTYPE/probability
-echo 100 > /debug/$FAILTYPE/interval
-echo -1 > /debug/$FAILTYPE/times
-echo 0 > /debug/$FAILTYPE/space
-echo 2 > /debug/$FAILTYPE/verbose
-echo 1 > /debug/$FAILTYPE/ignore-gfp-wait
+echo Y > /sys/kernel/debug/$FAILTYPE/task-filter
+echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+echo -1 > /sys/kernel/debug/$FAILTYPE/times
+echo 0 > /sys/kernel/debug/$FAILTYPE/space
+echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
 
 faulty_system()
 {
@@ -217,20 +217,20 @@ then
 	exit 1
 fi
 
-cat /sys/module/$module/sections/.text > /debug/$FAILTYPE/require-start
-cat /sys/module/$module/sections/.data > /debug/$FAILTYPE/require-end
+cat /sys/module/$module/sections/.text > /sys/kernel/debug/$FAILTYPE/require-start
+cat /sys/module/$module/sections/.data > /sys/kernel/debug/$FAILTYPE/require-end
 
-echo N > /debug/$FAILTYPE/task-filter
-echo 10 > /debug/$FAILTYPE/probability
-echo 100 > /debug/$FAILTYPE/interval
-echo -1 > /debug/$FAILTYPE/times
-echo 0 > /debug/$FAILTYPE/space
-echo 2 > /debug/$FAILTYPE/verbose
-echo 1 > /debug/$FAILTYPE/ignore-gfp-wait
-echo 1 > /debug/$FAILTYPE/ignore-gfp-highmem
-echo 10 > /debug/$FAILTYPE/stacktrace-depth
+echo N > /sys/kernel/debug/$FAILTYPE/task-filter
+echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+echo -1 > /sys/kernel/debug/$FAILTYPE/times
+echo 0 > /sys/kernel/debug/$FAILTYPE/space
+echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
+echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
+echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth
 
-trap "echo 0 > /debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
+trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
 
 echo "Injecting errors into the module $module... (interrupt to stop)"
 sleep 1000000
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt
index 1e7a769..053037a 100644
--- a/Documentation/kprobes.txt
+++ b/Documentation/kprobes.txt
@@ -507,9 +507,9 @@ http://www.linuxsymposium.org/2006/linuxsymposium_procv2.pdf (pages 101-115)
 Appendix A: The kprobes debugfs interface
 
 With recent kernels (> 2.6.20) the list of registered kprobes is visible
-under the /debug/kprobes/ directory (assuming debugfs is mounted at /debug).
+under the /sys/kernel/debug/kprobes/ directory (assuming debugfs is mounted at //sys/kernel/debug).
 
-/debug/kprobes/list: Lists all registered probes on the system
+/sys/kernel/debug/kprobes/list: Lists all registered probes on the system
 
 c015d71a  k  vfs_read+0x0
 c011a316  j  do_fork+0x0
@@ -525,7 +525,7 @@ virtual addresses that correspond to modules that've been unloaded),
 such probes are marked with [GONE]. If the probe is temporarily disabled,
 such probes are marked with [DISABLED].
 
-/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
+/sys/kernel/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
 
 Provides a knob to globally and forcibly turn registered kprobes ON or OFF.
 By default, all kprobes are enabled. By echoing "0" to this file, all
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..05f8378 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc.
                (dual licensed under the GPL v2)
 Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
 	     John Kacur, and David Teigland.
-
 Written for: 2.6.28-rc2
 
 Introduction
@@ -33,13 +32,26 @@ The File System
 Ftrace uses the debugfs file system to hold the control files as
 well as the files to display output.
 
-To mount the debugfs system:
+When debugfs is configured into the kernel (which selecting any ftrace
+option will do) the directory /sys/kernel/debug will be created. To mount
+this directory, you can add to your /etc/fstab file:
+
+ debugfs       /sys/kernel/debug          debugfs defaults        0       0
+
+Or you can mount it at run time with:
+
+ mount -t debugfs nodev /sys/kernel/debug
 
-  # mkdir /debug
-  # mount -t debugfs nodev /debug
+For quicker access to that directory you may want to make a soft link to
+it:
 
-( Note: it is more common to mount at /sys/kernel/debug, but for
-  simplicity this document will use /debug)
+ ln -s /sys/kernel/debug /debug
+
+Any selected ftrace option will also create a directory called tracing
+within the debugfs. The rest of the document will assume that you are in
+the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate
+on the files within that directory and not distract from the content with
+the extended "/sys/kernel/debug/tracing" path name.
 
 That's it! (assuming that you have ftrace configured into your kernel)
 
@@ -389,18 +401,18 @@ trace_options
 The trace_options file is used to control what gets printed in
 the trace output. To see what is available, simply cat the file:
 
-  cat /debug/tracing/trace_options
+  cat trace_options
   print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
   noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj
 
 To disable one of the options, echo in the option prepended with
 "no".
 
-  echo noprint-parent > /debug/tracing/trace_options
+  echo noprint-parent > trace_options
 
 To enable an option, leave off the "no".
 
-  echo sym-offset > /debug/tracing/trace_options
+  echo sym-offset > trace_options
 
 Here are the available options:
 
@@ -476,11 +488,11 @@ sched_switch
 This tracer simply records schedule switches. Here is an example
 of how to use it.
 
- # echo sched_switch > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo sched_switch > current_tracer
+ # echo 1 > tracing_enabled
  # sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 
 # tracer: sched_switch
 #
@@ -574,13 +586,13 @@ new trace is saved.
 To reset the maximum, echo 0 into tracing_max_latency. Here is
 an example:
 
- # echo irqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo irqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: irqsoff
 #
 irqsoff latency trace v1.1.5 on 2.6.26
@@ -681,13 +693,13 @@ Like the irqsoff tracer, it records the maximum latency for
 which preemption was disabled. The control of preemptoff tracer
 is much like the irqsoff tracer.
 
- # echo preemptoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptoff
 #
 preemptoff latency trace v1.1.5 on 2.6.26-rc8
@@ -828,13 +840,13 @@ tracer.
 Again, using this trace is much like the irqsoff and preemptoff
 tracers.
 
- # echo preemptirqsoff > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo preemptirqsoff > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # ls -ltr
  [...]
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: preemptirqsoff
 #
 preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
@@ -990,12 +1002,12 @@ slightly differently than we did with the previous tracers.
 Instead of performing an 'ls', we will run 'sleep 1' under
 'chrt' which changes the priority of the task.
 
- # echo wakeup > /debug/tracing/current_tracer
- # echo 0 > /debug/tracing/tracing_max_latency
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo wakeup > current_tracer
+ # echo 0 > tracing_max_latency
+ # echo 1 > tracing_enabled
  # chrt -f 5 sleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/latency_trace
+ # echo 0 > tracing_enabled
+ # cat latency_trace
 # tracer: wakeup
 #
 wakeup latency trace v1.1.5 on 2.6.26-rc8
@@ -1105,11 +1117,11 @@ can be done from the debug file system. Make sure the
 ftrace_enabled is set; otherwise this tracer is a nop.
 
  # sysctl kernel.ftrace_enabled=1
- # echo function > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo function > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1146,7 +1158,7 @@ int trace_fd;
 [...]
 int main(int argc, char *argv[]) {
 	[...]
-	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	trace_fd = open(tracing_file("tracing_enabled"), O_WRONLY);
 	[...]
 	if (condition_hit()) {
 		write(trace_fd, "0", 1);
@@ -1154,26 +1166,20 @@ int main(int argc, char *argv[]) {
 	[...]
 }
 
-Note: Here we hard coded the path name. The debugfs mount is not
-guaranteed to be at /debug (and is more commonly at
-/sys/kernel/debug). For simple one time traces, the above is
-sufficent. For anything else, a search through /proc/mounts may
-be needed to find where the debugfs file-system is mounted.
-
 
 Single thread tracing
 ---------------------
 
-By writing into /debug/tracing/set_ftrace_pid you can trace a
+By writing into set_ftrace_pid you can trace a
 single thread. For example:
 
-# cat /debug/tracing/set_ftrace_pid
+# cat set_ftrace_pid
 no pid
-# echo 3111 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/set_ftrace_pid
+# echo 3111 > set_ftrace_pid
+# cat set_ftrace_pid
 3111
-# echo function > /debug/tracing/current_tracer
-# cat /debug/tracing/trace | head
+# echo function > current_tracer
+# cat trace | head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1184,8 +1190,8 @@ no pid
      yum-updatesd-3111  [003]  1637.254683: lock_hrtimer_base <-hrtimer_try_to_cancel
      yum-updatesd-3111  [003]  1637.254685: fget_light <-do_sys_poll
      yum-updatesd-3111  [003]  1637.254686: pipe_poll <-do_sys_poll
-# echo -1 > /debug/tracing/set_ftrace_pid
-# cat /debug/tracing/trace |head
+# echo -1 > set_ftrace_pid
+# cat trace |head
  # tracer: function
  #
  #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
@@ -1207,6 +1213,51 @@ something like this simple program:
 #include <fcntl.h>
 #include <unistd.h>
 
+#define _STR(x) #x
+#define STR(x) _STR(x)
+#define MAX_PATH 256
+
+const char *find_debugfs(void)
+{
+       static char debugfs[MAX_PATH+1];
+       static int debugfs_found;
+       char type[100];
+       FILE *fp;
+ 
+       if (debugfs_found)
+               return debugfs;
+
+       if ((fp = fopen("/proc/mounts","r")) == NULL) {
+               perror("/proc/mounts");
+               return NULL;
+       }
+
+       while (fscanf(fp, "%*s %"
+                     STR(MAX_PATH)
+                     "s %99s %*s %*d %*d\n",
+                     debugfs, type) == 2) {
+               if (strcmp(type, "debugfs") == 0)
+                       break;
+       }
+       fclose(fp);
+
+       if (strcmp(type, "debugfs") != 0) {
+               fprintf(stderr, "debugfs not mounted");
+               return NULL;
+       }
+
+       debugfs_found = 1;
+
+       return debugfs;
+}
+
+const char *tracing_file(const char *file_name)
+{
+       static char trace_file[MAX_PATH+1];
+       snprintf(trace_file, MAX_PATH, "%s/%s", find_debugfs(), file_name);
+       return trace_file;
+}
+
 int main (int argc, char **argv)
 {
         if (argc < 1)
@@ -1217,12 +1268,12 @@ int main (int argc, char **argv)
                 char line[64];
                 int s;
 
-                ffd = open("/debug/tracing/current_tracer", O_WRONLY);
+                ffd = open(tracing_file("current_tracer"), O_WRONLY);
                 if (ffd < 0)
                         exit(-1);
                 write(ffd, "nop", 3);
 
-                fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
+                fd = open(tracing_file("set_ftrace_pid"), O_WRONLY);
                 s = sprintf(line, "%d\n", getpid());
                 write(fd, line, s);
 
@@ -1374,22 +1425,22 @@ want, depending on your needs.
   tracing_cpu_mask file) or you might sometimes see unordered
   function calls while cpu tracing switch.
 
-	hide: echo nofuncgraph-cpu > /debug/tracing/trace_options
-	show: echo funcgraph-cpu > /debug/tracing/trace_options
+	hide: echo nofuncgraph-cpu > trace_options
+	show: echo funcgraph-cpu > trace_options
 
 - The duration (function's time of execution) is displayed on
   the closing bracket line of a function or on the same line
   than the current function in case of a leaf one. It is default
   enabled.
 
-	hide: echo nofuncgraph-duration > /debug/tracing/trace_options
-	show: echo funcgraph-duration > /debug/tracing/trace_options
+	hide: echo nofuncgraph-duration > trace_options
+	show: echo funcgraph-duration > trace_options
 
 - The overhead field precedes the duration field in case of
   reached duration thresholds.
 
-	hide: echo nofuncgraph-overhead > /debug/tracing/trace_options
-	show: echo funcgraph-overhead > /debug/tracing/trace_options
+	hide: echo nofuncgraph-overhead > trace_options
+	show: echo funcgraph-overhead > trace_options
 	depends on: funcgraph-duration
 
   ie:
@@ -1418,8 +1469,8 @@ want, depending on your needs.
 - The task/pid field displays the thread cmdline and pid which
   executed the function. It is default disabled.
 
-	hide: echo nofuncgraph-proc > /debug/tracing/trace_options
-	show: echo funcgraph-proc > /debug/tracing/trace_options
+	hide: echo nofuncgraph-proc > trace_options
+	show: echo funcgraph-proc > trace_options
 
   ie:
 
@@ -1442,8 +1493,8 @@ want, depending on your needs.
   system clock since it started. A snapshot of this time is
   given on each entry/exit of functions
 
-	hide: echo nofuncgraph-abstime > /debug/tracing/trace_options
-	show: echo funcgraph-abstime > /debug/tracing/trace_options
+	hide: echo nofuncgraph-abstime > trace_options
+	show: echo funcgraph-abstime > trace_options
 
   ie:
 
@@ -1540,7 +1591,7 @@ listed in:
 
    available_filter_functions
 
- # cat /debug/tracing/available_filter_functions
+ # cat available_filter_functions
 put_prev_task_idle
 kmem_cache_create
 pick_next_task_rt
@@ -1552,12 +1603,12 @@ mutex_lock
 If I am only interested in sys_nanosleep and hrtimer_interrupt:
 
  # echo sys_nanosleep hrtimer_interrupt \
-		> /debug/tracing/set_ftrace_filter
- # echo ftrace > /debug/tracing/current_tracer
- # echo 1 > /debug/tracing/tracing_enabled
+		> set_ftrace_filter
+ # echo ftrace > current_tracer
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: ftrace
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1568,7 +1619,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt:
 
 To see which functions are being traced, you can cat the file:
 
- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_interrupt
 sys_nanosleep
 
@@ -1588,7 +1639,7 @@ Note: It is better to use quotes to enclose the wild cards,
       otherwise the shell may expand the parameters into names
       of files in the local directory.
 
- # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' > set_ftrace_filter
 
 Produces:
 
@@ -1609,7 +1660,7 @@ Produces:
 
 Notice that we lost the sys_nanosleep.
 
- # cat /debug/tracing/set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1635,17 +1686,17 @@ To append to the filters, use '>>'
 To clear out a filter so that all functions will be recorded
 again:
 
- # echo > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo > set_ftrace_filter
+ # cat set_ftrace_filter
  #
 
 Again, now we want to append.
 
- # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo sys_nanosleep > set_ftrace_filter
+ # cat set_ftrace_filter
 sys_nanosleep
- # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter
- # cat /debug/tracing/set_ftrace_filter
+ # echo 'hrtimer_*' >> set_ftrace_filter
+ # cat set_ftrace_filter
 hrtimer_run_queues
 hrtimer_run_pending
 hrtimer_init
@@ -1668,7 +1719,7 @@ hrtimer_init_sleeper
 The set_ftrace_notrace prevents those functions from being
 traced.
 
- # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+ # echo '*preempt*' '*lock*' > set_ftrace_notrace
 
 Produces:
 
@@ -1758,13 +1809,13 @@ the effect on the tracing is different. Every read from
 trace_pipe is consumed. This means that subsequent reads will be
 different. The trace is live.
 
- # echo function > /debug/tracing/current_tracer
- # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+ # echo function > current_tracer
+ # cat trace_pipe > /tmp/trace.out &
 [1] 4153
- # echo 1 > /debug/tracing/tracing_enabled
+ # echo 1 > tracing_enabled
  # usleep 1
- # echo 0 > /debug/tracing/tracing_enabled
- # cat /debug/tracing/trace
+ # echo 0 > tracing_enabled
+ # cat trace
 # tracer: function
 #
 #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
@@ -1800,7 +1851,7 @@ number listed is the number of entries that can be recorded per
 CPU. To know the full size, multiply the number of possible CPUS
 with the number of entries.
 
- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 1408 (units kilobytes)
 
 Note, to modify this, you must have tracing completely disabled.
@@ -1808,18 +1859,18 @@ To do that, echo "nop" into the current_tracer. If the
 current_tracer is not set to "nop", an EINVAL error will be
 returned.
 
- # echo nop > /debug/tracing/current_tracer
- # echo 10000 > /debug/tracing/buffer_size_kb
- # cat /debug/tracing/buffer_size_kb
+ # echo nop > current_tracer
+ # echo 10000 > buffer_size_kb
+ # cat buffer_size_kb
 10000 (units kilobytes)
 
 The number of pages which will be allocated is limited to a
 percentage of available memory. Allocating too much will produce
 an error.
 
- # echo 1000000000000 > /debug/tracing/buffer_size_kb
+ # echo 1000000000000 > buffer_size_kb
 -bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/buffer_size_kb
+ # cat buffer_size_kb
 85
 
 -----------
diff --git a/Documentation/trace/mmiotrace.txt b/Documentation/trace/mmiotrace.txt
index 5731c67..162effb 100644
--- a/Documentation/trace/mmiotrace.txt
+++ b/Documentation/trace/mmiotrace.txt
@@ -32,41 +32,41 @@ is no way to automatically detect if you are losing events due to CPUs racing.
 Usage Quick Reference
 ---------------------
 
-$ mount -t debugfs debugfs /debug
-$ echo mmiotrace > /debug/tracing/current_tracer
-$ cat /debug/tracing/trace_pipe > mydump.txt &
+$ mount -t debugfs debugfs /sys/kernel/debug
+$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
+$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
 Start X or whatever.
-$ echo "X is up" > /debug/tracing/trace_marker
-$ echo nop > /debug/tracing/current_tracer
+$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
+$ echo nop > /sys/kernel/debug/tracing/current_tracer
 Check for lost events.
 
 
 Usage
 -----
 
-Make sure debugfs is mounted to /debug. If not, (requires root privileges)
-$ mount -t debugfs debugfs /debug
+Make sure debugfs is mounted to /sys/kernel/debug. If not, (requires root privileges)
+$ mount -t debugfs debugfs /sys/kernel/debug
 
 Check that the driver you are about to trace is not loaded.
 
 Activate mmiotrace (requires root privileges):
-$ echo mmiotrace > /debug/tracing/current_tracer
+$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer
 
 Start storing the trace:
-$ cat /debug/tracing/trace_pipe > mydump.txt &
+$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt &
 The 'cat' process should stay running (sleeping) in the background.
 
 Load the driver you want to trace and use it. Mmiotrace will only catch MMIO
 accesses to areas that are ioremapped while mmiotrace is active.
 
 During tracing you can place comments (markers) into the trace by
-$ echo "X is up" > /debug/tracing/trace_marker
+$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker
 This makes it easier to see which part of the (huge) trace corresponds to
 which action. It is recommended to place descriptive markers about what you
 do.
 
 Shut down mmiotrace (requires root privileges):
-$ echo nop > /debug/tracing/current_tracer
+$ echo nop > /sys/kernel/debug/tracing/current_tracer
 The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
 pressing ctrl+c.
 
@@ -78,10 +78,10 @@ to view your kernel log and look for "mmiotrace has lost events" warning. If
 events were lost, the trace is incomplete. You should enlarge the buffers and
 try again. Buffers are enlarged by first seeing how large the current buffers
 are:
-$ cat /debug/tracing/buffer_size_kb
+$ cat /sys/kernel/debug/tracing/buffer_size_kb
 gives you a number. Approximately double this number and write it back, for
 instance:
-$ echo 128000 > /debug/tracing/buffer_size_kb
+$ echo 128000 > /sys/kernel/debug/tracing/buffer_size_kb
 Then start again from the top.
 
 If you are doing a trace for a driver project, e.g. Nouveau, you should also
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index dc7a8c3..9aa8932 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -430,7 +430,7 @@ static void pkt_sysfs_cleanup(void)
 /********************************************************************
   entries in debugfs
 
-  /debugfs/pktcdvd[0-7]/
+  /sys/kernel/debug/pktcdvd[0-7]/
 			info
 
  *******************************************************************/
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index c77c6c6..6ce0e26 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -105,7 +105,7 @@ int drm_debugfs_create_files(struct drm_info_list *files, int count,
 		ent = debugfs_create_file(files[i].name, S_IFREG | S_IRUGO,
 					  root, tmp, &drm_debugfs_fops);
 		if (!ent) {
-			DRM_ERROR("Cannot create /debugfs/dri/%s/%s\n",
+			DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s/%s\n",
 				  name, files[i].name);
 			drm_free(tmp, sizeof(struct drm_info_node),
 				 _DRM_DRIVER);
@@ -133,9 +133,9 @@ EXPORT_SYMBOL(drm_debugfs_create_files);
  * \param minor device minor number
  * \param root DRI debugfs dir entry.
  *
- * Create the DRI debugfs root entry "/debugfs/dri", the device debugfs root entry
- * "/debugfs/dri/%minor%/", and each entry in debugfs_list as
- * "/debugfs/dri/%minor%/%name%".
+ * Create the DRI debugfs root entry "/sys/kernel/debug/dri", the device debugfs root entry
+ * "/sys/kernel/debug/dri/%minor%/", and each entry in debugfs_list as
+ * "/sys/kernel/debug/dri/%minor%/%name%".
  */
 int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		     struct dentry *root)
@@ -148,7 +148,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 	sprintf(name, "%d", minor_id);
 	minor->debugfs_root = debugfs_create_dir(name, root);
 	if (!minor->debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri/%s\n", name);
+		DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s\n", name);
 		return -1;
 	}
 
@@ -165,7 +165,7 @@ int drm_debugfs_init(struct drm_minor *minor, int minor_id,
 		ret = dev->driver->debugfs_init(minor);
 		if (ret) {
 			DRM_ERROR("DRM: Driver failed to initialize "
-				  "/debugfs/dri.\n");
+				  "/sys/kernel/debug/dri.\n");
 			return ret;
 		}
 	}
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 019b7c5..1bf7efd 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -339,7 +339,7 @@ static int __init drm_core_init(void)
 
 	drm_debugfs_root = debugfs_create_dir("dri", NULL);
 	if (!drm_debugfs_root) {
-		DRM_ERROR("Cannot create /debugfs/dri\n");
+		DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
 		ret = -1;
 		goto err_p3;
 	}
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index b9631e3..b2a93c4 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -328,7 +328,7 @@ static int drm_get_minor(struct drm_device *dev, struct drm_minor **minor, int t
 #if defined(CONFIG_DEBUG_FS)
 	ret = drm_debugfs_init(new_minor, minor_id, drm_debugfs_root);
 	if (ret) {
-		DRM_ERROR("DRM: Failed to initialize /debugfs/dri.\n");
+		DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
 		goto err_g2;
 	}
 #endif
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 214a92d..a170cea 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2200,7 +2200,7 @@ config SKGE_DEBUG
        depends on SKGE && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/skge/ethX displays the state of the internal
+	 The file /sys/kernel/debug/skge/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
@@ -2226,7 +2226,7 @@ config SKY2_DEBUG
        depends on SKY2 && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/sky2/ethX displays the state of the internal
+	 The file /sys/kernel/debug/sky2/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
diff --git a/drivers/net/wimax/i2400m/i2400m.h b/drivers/net/wimax/i2400m/i2400m.h
index 3ae2df3..da2e8f2 100644
--- a/drivers/net/wimax/i2400m/i2400m.h
+++ b/drivers/net/wimax/i2400m/i2400m.h
@@ -389,7 +389,7 @@ struct i2400m {
 	unsigned ready:1;		/* all probing steps done */
 	unsigned rx_reorder:1;		/* RX reorder is enabled */
 	u8 trace_msg_from_user;		/* echo rx msgs to 'trace' pipe */
-					/* typed u8 so debugfs/u8 can tweak */
+					/* typed u8 so /sys/kernel/debug/u8 can tweak */
 	enum i2400m_system_state state;
 	wait_queue_head_t state_wq;	/* Woken up when on state updates */
 
diff --git a/drivers/net/wireless/ath5k/Kconfig b/drivers/net/wireless/ath5k/Kconfig
index 75383a5..fdfa708 100644
--- a/drivers/net/wireless/ath5k/Kconfig
+++ b/drivers/net/wireless/ath5k/Kconfig
@@ -27,11 +27,11 @@ config ATH5K_DEBUG
 	  Say Y, if and you will get debug options for ath5k.
 	  To use this, you need to mount debugfs:
 
-	  mkdir /debug/
-	  mount -t debugfs debug /debug/
+	  mkdir /sys/kernel/debug/
+	  mount -t debugfs debug /sys/kernel/debug/
 
 	  You will get access to files under:
-	  /debug/ath5k/phy0/
+	  /sys/kernel/debug/ath5k/phy0/
 
 	  To enable debug, pass the debug level to the debug module
 	  parameter. For example:
diff --git a/drivers/net/wireless/libertas/README b/drivers/net/wireless/libertas/README
index d860fc3..ab6a2d5 100644
--- a/drivers/net/wireless/libertas/README
+++ b/drivers/net/wireless/libertas/README
@@ -72,7 +72,7 @@ rdrf
 	location that is to be read.  This parameter must be specified in
 	hexadecimal (its possible to preceed preceding the number with a "0x").
 
-	Path: /debugfs/libertas_wireless/ethX/registers/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/registers/
 
 	Usage:
 		echo "0xa123" > rdmac ; cat rdmac
@@ -95,7 +95,7 @@ wrrf
 sleepparams
 	This command is used to set the sleepclock configurations
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage:
 		cat sleepparams: reads the current sleepclock configuration
@@ -115,7 +115,7 @@ subscribed_events
 	The subscribed_events directory contains the interface for the
 	subscribed events API.
 
-	Path: /debugfs/libertas_wireless/ethX/subscribed_events/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/subscribed_events/
 
 	Each event is represented by a filename. Each filename consists of the
 	following three fields:
@@ -165,7 +165,7 @@ subscribed_events
 extscan
 	This command is used to do a specific scan.
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage: echo "SSID" > extscan
 
@@ -179,7 +179,7 @@ getscantable
 	Display the current contents of the driver scan table (ie. get the
 	scan results).
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
 	Usage:
 		cat getscantable
@@ -188,7 +188,7 @@ setuserscan
 	Initiate a customized scan and retrieve the results
 
 
-	Path: /debugfs/libertas_wireless/ethX/
+	Path: /sys/kernel/debug/libertas_wireless/ethX/
 
     Usage:
        echo "[ARGS]" > setuserscan
diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index 52be564..9112380 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -51,8 +51,8 @@
  * debugfs interface
  *
  * To access this interface the user should:
- * # mkdir /debug
- * # mount -t debugfs none /debug
+ * # mkdir /sys/kernel/debug
+ * # mount -t debugfs none /sys/kernel/debug
  *
  * The lpfc debugfs directory hierarchy is:
  * lpfc/lpfcX/vportY
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 883cd44..99b7aad 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -406,7 +406,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
  *
  * Use tracing_on/tracing_off when you want to quickly turn on or off
  * tracing. It simply enables or disables the recording of the trace events.
- * This also corresponds to the user space debugfs/tracing/tracing_on
+ * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
  * file, which gives a means for the kernel and userspace to interact.
  * Place a tracing_off() in the kernel where you want tracing to end.
  * From user space, examine the trace, and then echo 1 > tracing_on
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index d35a7ee..9c9ac7d 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -197,7 +197,7 @@ static inline void tracepoint_synchronize_unregister(void)
  *	* This is how the trace record is structured and will
  *	* be saved into the ring buffer. These are the fields
  *	* that will be exposed to user-space in
- *	* /debug/tracing/events/<*>/format.
+ *	* /sys/kernel/debug/tracing/events/<*>/format.
  *	*
  *	* The declared 'local variable' is called '__entry'
  *	*
@@ -257,7 +257,7 @@ static inline void tracepoint_synchronize_unregister(void)
  * tracepoint callback (this is used by programmatic plugins and
  * can also by used by generic instrumentation like SystemTap), and
  * it is also used to expose a structured trace record in
- * /debug/tracing/events/.
+ * /sys/kernel/debug/tracing/events/.
  */
 
 #define TRACE_EVENT(name, proto, args, struct, assign, print)	\
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 417d198..e5ce28f 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -120,7 +120,7 @@ config IRQSOFF_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the preempt-off timing option can be
@@ -141,7 +141,7 @@ config PREEMPT_TRACER
 	  disabled by default and can be runtime (re-)started
 	  via:
 
-	      echo 0 > /debugfs/tracing/tracing_max_latency
+	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
 
 	  (Note that kernel size and overhead increases with this option
 	  enabled. This option and the irqs-off timing option can be
@@ -213,7 +213,7 @@ config TRACE_BRANCH_PROFILING
 	  This tracer profiles all the the likely and unlikely macros
 	  in the kernel. It will display the results in:
 
-	  /debugfs/tracing/profile_annotated_branch
+	  /sys/kernel/debug/tracing/profile_annotated_branch
 
 	  Note: this will add a significant overhead, only turn this
 	  on if you need to profile the system's use of these macros.
@@ -228,7 +228,7 @@ config PROFILE_ALL_BRANCHES
 	  taken in the kernel is recorded whether it hit or miss.
 	  The results will be displayed in:
 
-	  /debugfs/tracing/profile_branch
+	  /sys/kernel/debug/tracing/profile_branch
 
 	  This configuration, when enabled, will impose a great overhead
 	  on the system. This should only be enabled when the system
@@ -276,7 +276,7 @@ config STACK_TRACER
 	select KALLSYMS
 	help
 	  This special tracer records the maximum stack footprint of the
-	  kernel and displays it in debugfs/tracing/stack_trace.
+	  kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
 
 	  This tracer works by hooking into every function call that the
 	  kernel executes, and keeping a maximum stack depth value and
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index cda81ec..9b94d57 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -335,7 +335,7 @@ static raw_spinlock_t ftrace_max_lock =
 /*
  * Copy the new maximum trace into the separate maximum-trace
  * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /debugfs/tracing/latency_trace)
+ * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
  */
 static void
 __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
@@ -2366,21 +2366,21 @@ static const struct file_operations tracing_iter_fops = {
 
 static const char readme_msg[] =
 	"tracing mini-HOWTO:\n\n"
-	"# mkdir /debug\n"
-	"# mount -t debugfs nodev /debug\n\n"
-	"# cat /debug/tracing/available_tracers\n"
+	"# mkdir /sys/kernel/debug\n"
+	"# mount -t debugfs nodev /sys/kernel/debug\n\n"
+	"# cat /sys/kernel/debug/tracing/available_tracers\n"
 	"wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
-	"# cat /debug/tracing/current_tracer\n"
+	"# cat /sys/kernel/debug/tracing/current_tracer\n"
 	"nop\n"
-	"# echo sched_switch > /debug/tracing/current_tracer\n"
-	"# cat /debug/tracing/current_tracer\n"
+	"# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
+	"# cat /sys/kernel/debug/tracing/current_tracer\n"
 	"sched_switch\n"
-	"# cat /debug/tracing/trace_options\n"
+	"# cat /sys/kernel/debug/tracing/trace_options\n"
 	"noprint-parent nosym-offset nosym-addr noverbose\n"
-	"# echo print-parent > /debug/tracing/trace_options\n"
-	"# echo 1 > /debug/tracing/tracing_enabled\n"
-	"# cat /debug/tracing/trace > /tmp/trace.txt\n"
-	"# echo 0 > /debug/tracing/tracing_enabled\n"
+	"# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
+	"# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
+	"# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
+	"# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
 ;
 
 static ssize_t
diff --git a/scripts/tracing/draw_functrace.py b/scripts/tracing/draw_functrace.py
index 902f9a9..66f4d1b 100644
--- a/scripts/tracing/draw_functrace.py
+++ b/scripts/tracing/draw_functrace.py
@@ -12,10 +12,10 @@ calls. Only the functions's names and the the call time are provided.
 
 Usage:
 	Be sure that you have CONFIG_FUNCTION_TRACER
-	# mkdir /debugfs
-	# mount -t debug debug /debug
-	# echo function > /debug/tracing/current_tracer
-	$ cat /debug/tracing/trace_pipe > ~/raw_trace_func
+	# mkdir /sys/kernel/debug
+	# mount -t debug debug /sys/kernel/debug
+	# echo function > /sys/kernel/debug/tracing/current_tracer
+	$ cat /sys/kernel/debug/tracing/trace_pipe > ~/raw_trace_func
 	Wait some times but not too much, the script is a bit slow.
 	Break the pipe (Ctrl + Z)
 	$ scripts/draw_functrace.py < raw_trace_func > draw_functrace
-- 
1.6.3.1



 
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GeunSik Lim ( Samsung Electronics )
e-Mail  :1) geunsik.lim@samsung.com
         2) leemgs@gmail.com , leemgs1@gmail.com
HomePage: http://blog.naver.com/invain/
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