[for-next][PATCH 0/5] tracing: Updates for 3.20

[for-next][PATCH 0/5] tracing: Updates for 3.20

[Steven Rostedt]

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
for-next

Head SHA1: 7eeafbcab47fe9860e5106286db83d60e3f35644


Borislav Petkov (1):
      tracing: Remove newline from trace_printk warning banner

Dave Martin (1):
      tracing: Add array printing helper

Steven Rostedt (Red Hat) (2):
      tracing: Make tracing_init_dentry_tr() static
      tracing: Separate out initializing top level dir from instances

Tina Ruchandani (1):
      trace: Use 64-bit timekeeping

----
 include/linux/ftrace_event.h         |  4 +++
 include/trace/ftrace.h               |  9 ++++++
 kernel/trace/ring_buffer_benchmark.c | 18 ++++++------
 kernel/trace/trace.c                 | 54 +++++++++++++++++++++---------------
 kernel/trace/trace.h                 |  1 -
 kernel/trace/trace_output.c          | 44 +++++++++++++++++++++++++++++
 6 files changed, 97 insertions(+), 33 deletions(-)

[for-next][PATCH 1/5] tracing: Remove newline from trace_printk warning banner

[Steven Rostedt]

[-- Attachment #1: 0001-tracing-Remove-newline-from-trace_printk-warning-ban.patch --]
[-- Type: text/plain, Size: 1346 bytes --]

From: Borislav Petkov <bp@suse.de>

Remove the output-confusing newline below:

[    0.191328]
**********************************************************
[    0.191493] **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
[    0.191586] **                                                      **
...

Link: http://lkml.kernel.org/r/1422375440-31970-1-git-send-email-bp@alien8.de

Signed-off-by: Borislav Petkov <bp@suse.de>
[ added an extra '\n' by itself, to keep what it was suppose to do ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index acd27555dc5b..f82e53b0e5a7 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2036,7 +2036,8 @@ void trace_printk_init_buffers(void)
 
 	/* trace_printk() is for debug use only. Don't use it in production. */
 
-	pr_warning("\n**********************************************************\n");
+	pr_warning("\n");
+	pr_warning("**********************************************************\n");
 	pr_warning("**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **\n");
 	pr_warning("**                                                      **\n");
 	pr_warning("** trace_printk() being used. Allocating extra memory.  **\n");
-- 
2.1.4

[for-next][PATCH 2/5] tracing: Add array printing helper

[Steven Rostedt]

[-- Attachment #1: 0002-tracing-Add-array-printing-helper.patch --]
[-- Type: text/plain, Size: 4301 bytes --]

From: Dave Martin <Dave.Martin@arm.com>

If a trace event contains an array, there is currently no standard
way to format this for text output.  Drivers are currently hacking
around this by a) local hacks that use the trace_seq functionailty
directly, or b) just not printing that information.  For fixed size
arrays, formatting of the elements can be open-coded, but this gets
cumbersome for arrays of non-trivial size.

These approaches result in non-standard content of the event format
description delivered to userspace, so userland tools needs to be
taught to understand and parse each array printing method
individually.

This patch implements a __print_array() helper that tracepoint
implementations can use instead of reinventing it.  A simple C-style
syntax is used to delimit the array and its elements {like,this}.

So that the helpers can be used with large static arrays as well as
dynamic arrays, they take a pointer and element count: they can be
used with __get_dynamic_array() for use with dynamic arrays.
Link: http://lkml.kernel.org/r/1422449335-8289-2-git-send-email-javi.merino@arm.com

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/linux/ftrace_event.h |  4 ++++
 include/trace/ftrace.h       |  9 +++++++++
 kernel/trace/trace_output.c  | 44 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 57 insertions(+)

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 0bebb5c348b8..5aa4a9269547 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -44,6 +44,10 @@ const char *ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
 const char *ftrace_print_hex_seq(struct trace_seq *p,
 				 const unsigned char *buf, int len);
 
+const char *ftrace_print_array_seq(struct trace_seq *p,
+				   const void *buf, int buf_len,
+				   size_t el_size);
+
 struct trace_iterator;
 struct trace_event;
 
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 139b5067345b..304901fc5f34 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -263,6 +263,14 @@
 #undef __print_hex
 #define __print_hex(buf, buf_len) ftrace_print_hex_seq(p, buf, buf_len)
 
+#undef __print_array
+#define __print_array(array, count, el_size)				\
+	({								\
+		BUILD_BUG_ON(el_size != 1 && el_size != 2 &&		\
+			     el_size != 4 && el_size != 8);		\
+		ftrace_print_array_seq(p, array, count, el_size);	\
+	})
+
 #undef DECLARE_EVENT_CLASS
 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
 static notrace enum print_line_t					\
@@ -674,6 +682,7 @@ static inline void ftrace_test_probe_##call(void)			\
 #undef __get_dynamic_array_len
 #undef __get_str
 #undef __get_bitmask
+#undef __print_array
 
 #undef TP_printk
 #define TP_printk(fmt, args...) "\"" fmt "\", "  __stringify(args)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index b77b9a697619..692bf7184c8c 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -177,6 +177,50 @@ ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
 }
 EXPORT_SYMBOL(ftrace_print_hex_seq);
 
+const char *
+ftrace_print_array_seq(struct trace_seq *p, const void *buf, int buf_len,
+		       size_t el_size)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	const char *prefix = "";
+	void *ptr = (void *)buf;
+
+	trace_seq_putc(p, '{');
+
+	while (ptr < buf + buf_len) {
+		switch (el_size) {
+		case 1:
+			trace_seq_printf(p, "%s0x%x", prefix,
+					 *(u8 *)ptr);
+			break;
+		case 2:
+			trace_seq_printf(p, "%s0x%x", prefix,
+					 *(u16 *)ptr);
+			break;
+		case 4:
+			trace_seq_printf(p, "%s0x%x", prefix,
+					 *(u32 *)ptr);
+			break;
+		case 8:
+			trace_seq_printf(p, "%s0x%llx", prefix,
+					 *(u64 *)ptr);
+			break;
+		default:
+			trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
+					 *(u8 *)ptr);
+			el_size = 1;
+		}
+		prefix = ",";
+		ptr += el_size;
+	}
+
+	trace_seq_putc(p, '}');
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+EXPORT_SYMBOL(ftrace_print_array_seq);
+
 int ftrace_raw_output_prep(struct trace_iterator *iter,
 			   struct trace_event *trace_event)
 {
-- 
2.1.4

[for-next][PATCH 3/5] trace: Use 64-bit timekeeping

[Steven Rostedt]

[-- Attachment #1: 0003-trace-Use-64-bit-timekeeping.patch --]
[-- Type: text/plain, Size: 2838 bytes --]

From: Tina Ruchandani <ruchandani.tina@gmail.com>

The ring_buffer_producer uses 'struct timeval' to measure
its start and end times. 'struct timeval' on 32-bit systems
will have its tv_sec value overflow in year 2038 and beyond.
This patch replaces struct timeval with 'ktime_t' which uses
64-bit representation for nanoseconds.

Link: http://lkml.kernel.org/r/20150128141611.GA2701@tinar

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/ring_buffer_benchmark.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 3f9e328c30b5..13d945c0d03f 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -7,7 +7,7 @@
 #include <linux/completion.h>
 #include <linux/kthread.h>
 #include <linux/module.h>
-#include <linux/time.h>
+#include <linux/ktime.h>
 #include <asm/local.h>
 
 struct rb_page {
@@ -17,7 +17,7 @@ struct rb_page {
 };
 
 /* run time and sleep time in seconds */
-#define RUN_TIME	10
+#define RUN_TIME	10ULL
 #define SLEEP_TIME	10
 
 /* number of events for writer to wake up the reader */
@@ -212,8 +212,7 @@ static void ring_buffer_consumer(void)
 
 static void ring_buffer_producer(void)
 {
-	struct timeval start_tv;
-	struct timeval end_tv;
+	ktime_t start_time, end_time, timeout;
 	unsigned long long time;
 	unsigned long long entries;
 	unsigned long long overruns;
@@ -227,7 +226,8 @@ static void ring_buffer_producer(void)
 	 * make the system stall)
 	 */
 	trace_printk("Starting ring buffer hammer\n");
-	do_gettimeofday(&start_tv);
+	start_time = ktime_get();
+	timeout = ktime_add_ns(start_time, RUN_TIME * NSEC_PER_SEC);
 	do {
 		struct ring_buffer_event *event;
 		int *entry;
@@ -244,7 +244,7 @@ static void ring_buffer_producer(void)
 				ring_buffer_unlock_commit(buffer, event);
 			}
 		}
-		do_gettimeofday(&end_tv);
+		end_time = ktime_get();
 
 		cnt++;
 		if (consumer && !(cnt % wakeup_interval))
@@ -264,7 +264,7 @@ static void ring_buffer_producer(void)
 			cond_resched();
 #endif
 
-	} while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test);
+	} while (ktime_before(end_time, timeout) && !kill_test);
 	trace_printk("End ring buffer hammer\n");
 
 	if (consumer) {
@@ -280,9 +280,7 @@ static void ring_buffer_producer(void)
 		wait_for_completion(&read_done);
 	}
 
-	time = end_tv.tv_sec - start_tv.tv_sec;
-	time *= USEC_PER_SEC;
-	time += (long long)((long)end_tv.tv_usec - (long)start_tv.tv_usec);
+	time = ktime_us_delta(end_time, start_time);
 
 	entries = ring_buffer_entries(buffer);
 	overruns = ring_buffer_overruns(buffer);
-- 
2.1.4

[for-next][PATCH 4/5] tracing: Make tracing_init_dentry_tr() static

[Steven Rostedt]

[-- Attachment #1: 0004-tracing-Make-tracing_init_dentry_tr-static.patch --]
[-- Type: text/plain, Size: 1270 bytes --]

From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>

tracing_init_dentry_tr() is not used outside of trace.c, it should
be static.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace.c | 2 +-
 kernel/trace/trace.h | 1 -
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index f82e53b0e5a7..2668a0d742ee 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5815,7 +5815,7 @@ static __init int register_snapshot_cmd(void)
 static inline __init int register_snapshot_cmd(void) { return 0; }
 #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */
 
-struct dentry *tracing_init_dentry_tr(struct trace_array *tr)
+static struct dentry *tracing_init_dentry_tr(struct trace_array *tr)
 {
 	if (tr->dir)
 		return tr->dir;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 0eddfeb05fee..dd8205a35760 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -542,7 +542,6 @@ struct dentry *trace_create_file(const char *name,
 				 void *data,
 				 const struct file_operations *fops);
 
-struct dentry *tracing_init_dentry_tr(struct trace_array *tr);
 struct dentry *tracing_init_dentry(void);
 
 struct ring_buffer_event;
-- 
2.1.4

[for-next][PATCH 5/5] tracing: Separate out initializing top level dir from instances

[Steven Rostedt]

[-- Attachment #1: 0005-tracing-Separate-out-initializing-top-level-dir-from.patch --]
[-- Type: text/plain, Size: 3495 bytes --]

From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>

The top level trace array is treated a little different than the
instances, as it has to deal with more of the general tracing.
The tr->dir is the tracing directory, which is an immutable
dentry, where as the tr->dir of instances are the dentry that
was created, and can be destroyed later. These should have different
functions accessing them.

As only tracing_init_dentry() deals with the top level array, fold
the code for it into that function, and remove the trace_init_dentry_tr()
that was also used by the instances to get their directory dentry.

Add a tracing_get_dentry() to just get the tracing dir entry for
instances as well as the top level array.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace.c | 51 ++++++++++++++++++++++++++++++---------------------
 1 file changed, 30 insertions(+), 21 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2668a0d742ee..5afce60e1b68 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5815,28 +5815,11 @@ static __init int register_snapshot_cmd(void)
 static inline __init int register_snapshot_cmd(void) { return 0; }
 #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */
 
-static struct dentry *tracing_init_dentry_tr(struct trace_array *tr)
+static struct dentry *tracing_get_dentry(struct trace_array *tr)
 {
-	if (tr->dir)
-		return tr->dir;
-
-	if (!debugfs_initialized())
-		return ERR_PTR(-ENODEV);
-
-	if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
-		tr->dir = debugfs_create_dir("tracing", NULL);
-
-	if (!tr->dir)
-		pr_warn_once("Could not create debugfs directory 'tracing'\n");
-
 	return tr->dir;
 }
 
-struct dentry *tracing_init_dentry(void)
-{
-	return tracing_init_dentry_tr(&global_trace);
-}
-
 static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu)
 {
 	struct dentry *d_tracer;
@@ -5844,7 +5827,7 @@ static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu)
 	if (tr->percpu_dir)
 		return tr->percpu_dir;
 
-	d_tracer = tracing_init_dentry_tr(tr);
+	d_tracer = tracing_get_dentry(tr);
 	if (IS_ERR(d_tracer))
 		return NULL;
 
@@ -6047,7 +6030,7 @@ static struct dentry *trace_options_init_dentry(struct trace_array *tr)
 	if (tr->options)
 		return tr->options;
 
-	d_tracer = tracing_init_dentry_tr(tr);
+	d_tracer = tracing_get_dentry(tr);
 	if (IS_ERR(d_tracer))
 		return NULL;
 
@@ -6532,6 +6515,33 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
 
 }
 
+/**
+ * tracing_init_dentry - initialize top level trace array
+ *
+ * This is called when creating files or directories in the tracing
+ * directory. It is called via fs_initcall() by any of the boot up code
+ * and expects to return the dentry of the top level tracing directory.
+ */
+struct dentry *tracing_init_dentry(void)
+{
+	struct trace_array *tr = &global_trace;
+
+	if (tr->dir)
+		return tr->dir;
+
+	if (WARN_ON(!debugfs_initialized()))
+		return ERR_PTR(-ENODEV);
+
+	tr->dir = debugfs_create_dir("tracing", NULL);
+
+	if (!tr->dir) {
+		pr_warn_once("Could not create debugfs directory 'tracing'\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	return tr->dir;
+}
+
 static __init int tracer_init_debugfs(void)
 {
 	struct dentry *d_tracer;
@@ -6772,7 +6782,6 @@ __init static int tracer_alloc_buffers(void)
 	int ring_buf_size;
 	int ret = -ENOMEM;
 
-
 	if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL))
 		goto out;
 
-- 
2.1.4