* [for-next][PATCH 00/19] tracing: Updates for 4.18
@ 2018-05-29 15:23 Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 01/19] trace: Use -mcount-record for dynamic ftrace Steven Rostedt
` (18 more replies)
0 siblings, 19 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
for-next
Head SHA1: 086d713d2535b389de1893d2f3874e9cfb6dbdf3
Andi Kleen (1):
trace: Use -mcount-record for dynamic ftrace
Lee, Chun-Yi (1):
tracepoints: Fix the descriptions of tracepoint_probe_register{_prio}
Steven Rostedt (VMware) (16):
tracing: Do not reference event data in post call triggers
tracing: Add __find_event_file() to find event files without restrictions
tracing: Have event_trace_init() called by trace_init_tracefs()
tracing: Add brackets in ftrace event dynamic arrays
tracing: Do not show filter file for ftrace internal events
tracing: Add trigger file for trace_markers tracefs/ftrace/print
tracing: Have zero size length in filter logic be full string
tracing: Prevent further users of zero size static arrays in trace events
tracing: Allow histogram triggers to access ftrace internal events
tracing: Document trace_marker triggers
ftrace/selftest: Have the reset_trigger code be a bit more careful
ftrace/selftest: Fix reset_trigger() to handle triggers with filters
tracing/selftest: Add selftests to test trace_marker histogram triggers
tracing/selftest: Add test to test hist trigger between kernel event and trace_marker
tracing/selftest: Add test to test simple snapshot trigger for trace_marker
ring-buffer: Fix a bunch of typos in comments
Vasyl Gomonovych (1):
ring-buffer: Fix typo in comment
----
Documentation/trace/events.rst | 6 +-
Documentation/trace/ftrace.rst | 5 +
Documentation/trace/histogram.txt | 545 ++++++++++++++++++++-
include/linux/ring_buffer.h | 2 +-
include/linux/trace_events.h | 3 +-
include/trace/trace_events.h | 1 +
kernel/trace/ring_buffer.c | 20 +-
kernel/trace/trace.c | 19 +
kernel/trace/trace.h | 9 +-
kernel/trace/trace_entries.h | 6 +-
kernel/trace/trace_events.c | 36 +-
kernel/trace/trace_events_filter.c | 23 +-
kernel/trace/trace_events_hist.c | 2 +-
kernel/trace/trace_events_trigger.c | 6 +-
kernel/trace/trace_export.c | 9 +-
kernel/tracepoint.c | 3 +-
scripts/Makefile.build | 6 +
tools/testing/selftests/ftrace/test.d/functions | 23 +-
.../test.d/trigger/trigger-trace-marker-hist.tc | 49 ++
.../trigger/trigger-trace-marker-snapshot.tc | 74 +++
.../trigger-trace-marker-synthetic-kernel.tc | 68 +++
.../trigger/trigger-trace-marker-synthetic.tc | 66 +++
22 files changed, 927 insertions(+), 54 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic-kernel.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc
^ permalink raw reply [flat|nested] 20+ messages in thread
* [for-next][PATCH 01/19] trace: Use -mcount-record for dynamic ftrace
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 02/19] tracepoints: Fix the descriptions of tracepoint_probe_register{_prio} Steven Rostedt
` (17 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Andi Kleen
[-- Attachment #1: 0001-trace-Use-mcount-record-for-dynamic-ftrace.patch --]
[-- Type: text/plain, Size: 1380 bytes --]
From: Andi Kleen <ak@linux.intel.com>
gcc 5 supports a new -mcount-record option to generate ftrace
tables directly. This avoids the need to run record_mcount
manually.
Use this option when available.
So far doesn't use -mcount-nop, which also exists now.
This is needed to make ftrace work with LTO because the
normal record-mcount script doesn't run over the link
time output.
It should also improve build times slightly in the general
case.
Link: http://lkml.kernel.org/r/20171127213423.27218-12-andi@firstfloor.org
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
scripts/Makefile.build | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 8bdb1dc4072c..dcbca18011bb 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -207,6 +207,11 @@ cmd_modversions_c = \
endif
ifdef CONFIG_FTRACE_MCOUNT_RECORD
+# gcc 5 supports generating the mcount tables directly
+ifneq ($(call cc-option,-mrecord-mcount,y),y)
+KBUILD_CFLAGS += -mrecord-mcount
+else
+# else do it all manually
ifdef BUILD_C_RECORDMCOUNT
ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
RECORDMCOUNT_FLAGS = -w
@@ -259,6 +264,7 @@ ifneq ($(RETPOLINE_CFLAGS),)
objtool_args += --retpoline
endif
endif
+endif
ifdef CONFIG_MODVERSIONS
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 02/19] tracepoints: Fix the descriptions of tracepoint_probe_register{_prio}
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 01/19] trace: Use -mcount-record for dynamic ftrace Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 03/19] tracing: Do not reference event data in post call triggers Steven Rostedt
` (16 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Lee, Chun-Yi
[-- Attachment #1: 0002-tracepoints-Fix-the-descriptions-of-tracepoint_probe.patch --]
[-- Type: text/plain, Size: 1232 bytes --]
From: "Lee, Chun-Yi" <joeyli.kernel@gmail.com>
The description of tracepoint_probe_register duplicates
with tracepoint_probe_register_prio. This patch cleans up
the descriptions.
Link: http://lkml.kernel.org/r/20170616082643.7311-1-jlee@suse.com
Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/tracepoint.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 1e37da2e0c25..6dc6356c3327 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -257,7 +257,7 @@ static int tracepoint_remove_func(struct tracepoint *tp,
}
/**
- * tracepoint_probe_register - Connect a probe to a tracepoint
+ * tracepoint_probe_register_prio - Connect a probe to a tracepoint with priority
* @tp: tracepoint
* @probe: probe handler
* @data: tracepoint data
@@ -290,7 +290,6 @@ EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio);
* @tp: tracepoint
* @probe: probe handler
* @data: tracepoint data
- * @prio: priority of this function over other registered functions
*
* Returns 0 if ok, error value on error.
* Note: if @tp is within a module, the caller is responsible for
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 03/19] tracing: Do not reference event data in post call triggers
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 01/19] trace: Use -mcount-record for dynamic ftrace Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 02/19] tracepoints: Fix the descriptions of tracepoint_probe_register{_prio} Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 04/19] tracing: Add __find_event_file() to find event files without restrictions Steven Rostedt
` (15 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Masami Hiramatsu, Namhyung Kim
[-- Attachment #1: 0003-tracing-Do-not-reference-event-data-in-post-call-tri.patch --]
[-- Type: text/plain, Size: 3653 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Trace event triggers can be called before or after the event has been
committed. If it has been called after the commit, there's a possibility
that the event no longer exists. Currently, the two post callers is the
trigger to disable tracing (traceoff) and the one that will record a stack
dump (stacktrace). Neither of them reference the trace event entry record,
as that would lead to a race condition that could pass in corrupted data.
To prevent any other users of the post data triggers from using the trace
event record, pass in NULL to the post call trigger functions for the event
record, as they should never need to use them in the first place.
This does not fix any bug, but prevents bugs from happening by new post call
trigger users.
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace_events.h | 3 +--
kernel/trace/trace.h | 4 ++--
kernel/trace/trace_events_trigger.c | 6 ++----
3 files changed, 5 insertions(+), 8 deletions(-)
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 2bde3eff564c..d1c442d9bd85 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -435,8 +435,7 @@ event_triggers_call(struct trace_event_file *file, void *rec,
struct ring_buffer_event *event);
extern void
event_triggers_post_call(struct trace_event_file *file,
- enum event_trigger_type tt,
- void *rec, struct ring_buffer_event *event);
+ enum event_trigger_type tt);
bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 507954b4e058..6bfc2467479c 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1334,7 +1334,7 @@ event_trigger_unlock_commit(struct trace_event_file *file,
trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
if (tt)
- event_triggers_post_call(file, tt, entry, event);
+ event_triggers_post_call(file, tt);
}
/**
@@ -1367,7 +1367,7 @@ event_trigger_unlock_commit_regs(struct trace_event_file *file,
irq_flags, pc, regs);
if (tt)
- event_triggers_post_call(file, tt, entry, event);
+ event_triggers_post_call(file, tt);
}
#define FILTER_PRED_INVALID ((unsigned short)-1)
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 8b5bdcf64871..d18249683682 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -97,7 +97,6 @@ EXPORT_SYMBOL_GPL(event_triggers_call);
* event_triggers_post_call - Call 'post_triggers' for a trace event
* @file: The trace_event_file associated with the event
* @tt: enum event_trigger_type containing a set bit for each trigger to invoke
- * @rec: The trace entry for the event
*
* For each trigger associated with an event, invoke the trigger
* function registered with the associated trigger command, if the
@@ -108,8 +107,7 @@ EXPORT_SYMBOL_GPL(event_triggers_call);
*/
void
event_triggers_post_call(struct trace_event_file *file,
- enum event_trigger_type tt,
- void *rec, struct ring_buffer_event *event)
+ enum event_trigger_type tt)
{
struct event_trigger_data *data;
@@ -117,7 +115,7 @@ event_triggers_post_call(struct trace_event_file *file,
if (data->paused)
continue;
if (data->cmd_ops->trigger_type & tt)
- data->ops->func(data, rec, event);
+ data->ops->func(data, NULL, NULL);
}
}
EXPORT_SYMBOL_GPL(event_triggers_post_call);
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 04/19] tracing: Add __find_event_file() to find event files without restrictions
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (2 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 03/19] tracing: Do not reference event data in post call triggers Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 05/19] tracing: Have event_trace_init() called by trace_init_tracefs() Steven Rostedt
` (14 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0004-tracing-Add-__find_event_file-to-find-event-files-wi.patch --]
[-- Type: text/plain, Size: 2991 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
By adding the function __find_event_file() that can search for files without
restrictions, such as if the event associated with the file has a reg
function, or if it has the "ignore" flag set, the files that are associated
to ftrace internal events (like trace_marker and function events) can be
found and used.
find_event_file() still returns a "filtered" file, as most callers need a
valid trace event file. One created by the trace_events.h macros and not one
created for parsing ftrace specific events.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace.h | 3 +++
kernel/trace/trace_events.c | 22 +++++++++++++++++-----
2 files changed, 20 insertions(+), 5 deletions(-)
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 6bfc2467479c..07c43960a704 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1454,6 +1454,9 @@ extern void trace_event_enable_tgid_record(bool enable);
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
extern int event_trace_del_tracer(struct trace_array *tr);
+extern struct trace_event_file *__find_event_file(struct trace_array *tr,
+ const char *system,
+ const char *event);
extern struct trace_event_file *find_event_file(struct trace_array *tr,
const char *system,
const char *event);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 05c7172c6667..caf76355f0a3 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2473,8 +2473,9 @@ __trace_add_event_dirs(struct trace_array *tr)
}
}
+/* Returns any file that matches the system and event */
struct trace_event_file *
-find_event_file(struct trace_array *tr, const char *system, const char *event)
+__find_event_file(struct trace_array *tr, const char *system, const char *event)
{
struct trace_event_file *file;
struct trace_event_call *call;
@@ -2485,10 +2486,7 @@ find_event_file(struct trace_array *tr, const char *system, const char *event)
call = file->event_call;
name = trace_event_name(call);
- if (!name || !call->class || !call->class->reg)
- continue;
-
- if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
+ if (!name || !call->class)
continue;
if (strcmp(event, name) == 0 &&
@@ -2498,6 +2496,20 @@ find_event_file(struct trace_array *tr, const char *system, const char *event)
return NULL;
}
+/* Returns valid trace event files that match system and event */
+struct trace_event_file *
+find_event_file(struct trace_array *tr, const char *system, const char *event)
+{
+ struct trace_event_file *file;
+
+ file = __find_event_file(tr, system, event);
+ if (!file || !file->event_call->class->reg ||
+ file->event_call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
+ return NULL;
+
+ return file;
+}
+
#ifdef CONFIG_DYNAMIC_FTRACE
/* Avoid typos */
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 05/19] tracing: Have event_trace_init() called by trace_init_tracefs()
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (3 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 04/19] tracing: Add __find_event_file() to find event files without restrictions Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 06/19] tracing: Add brackets in ftrace event dynamic arrays Steven Rostedt
` (13 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0005-tracing-Have-event_trace_init-called-by-trace_init_t.patch --]
[-- Type: text/plain, Size: 2279 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Instead of having both trace_init_tracefs() and event_trace_init() be called
by fs_initcall() routines, have event_trace_init() called directly by
trace_init_tracefs(). This will guarantee order of how the events are
created with respect to the rest of the ftrace infrastructure. This is
needed to be able to assoctiate event files with ftrace internal events,
such as the trace_marker.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace.c | 2 ++
kernel/trace/trace.h | 1 +
kernel/trace/trace_events.c | 4 +---
3 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bcd93031d042..d5000cba5a27 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -8111,6 +8111,8 @@ static __init int tracer_init_tracefs(void)
if (IS_ERR(d_tracer))
return 0;
+ event_trace_init();
+
init_tracer_tracefs(&global_trace, d_tracer);
ftrace_init_tracefs_toplevel(&global_trace, d_tracer);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 07c43960a704..d0319cbacf11 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1451,6 +1451,7 @@ trace_find_event_field(struct trace_event_call *call, char *name);
extern void trace_event_enable_cmd_record(bool enable);
extern void trace_event_enable_tgid_record(bool enable);
+extern int event_trace_init(void);
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
extern int event_trace_del_tracer(struct trace_array *tr);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index caf76355f0a3..5b647904a65b 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -3144,7 +3144,7 @@ static __init int event_trace_enable_again(void)
early_initcall(event_trace_enable_again);
-static __init int event_trace_init(void)
+__init int event_trace_init(void)
{
struct trace_array *tr;
struct dentry *d_tracer;
@@ -3189,8 +3189,6 @@ void __init trace_event_init(void)
event_trace_enable();
}
-fs_initcall(event_trace_init);
-
#ifdef CONFIG_FTRACE_STARTUP_TEST
static DEFINE_SPINLOCK(test_spinlock);
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 06/19] tracing: Add brackets in ftrace event dynamic arrays
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (4 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 05/19] tracing: Have event_trace_init() called by trace_init_tracefs() Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 07/19] tracing: Do not show filter file for ftrace internal events Steven Rostedt
` (12 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0006-tracing-Add-brackets-in-ftrace-event-dynamic-arrays.patch --]
[-- Type: text/plain, Size: 1169 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
The dynamic arrays defined for ftrace internal events, such as the buf field
for trace_marker (ftrace/print) did not have brackets which makes the filter
code not accept it as a string. This is not currently an issues because the
filter code doesn't do anything for these events, but they will in the
future, and this needs to be fixed for when it does.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace_export.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index 548e62eb5c46..d842f1eadfe5 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -117,7 +117,7 @@ static void __always_unused ____ftrace_check_##name(void) \
#undef __dynamic_array
#define __dynamic_array(type, item) \
- ret = trace_define_field(event_call, #type, #item, \
+ ret = trace_define_field(event_call, #type "[]", #item, \
offsetof(typeof(field), item), \
0, is_signed_type(type), filter_type);\
if (ret) \
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 07/19] tracing: Do not show filter file for ftrace internal events
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (5 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 06/19] tracing: Add brackets in ftrace event dynamic arrays Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 08/19] tracing: Add trigger file for trace_markers tracefs/ftrace/print Steven Rostedt
` (11 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0007-tracing-Do-not-show-filter-file-for-ftrace-internal-.patch --]
[-- Type: text/plain, Size: 1442 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
The filter file in the ftrace internal events, like in
/sys/kernel/tracing/events/ftrace/function/filter is not attached to any
functionality. Do not create them as they are meaningless.
In the future, if an ftrace internal event gets filter functionality, then
it will need to create it directly.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace_events.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 5b647904a65b..14ff4ff3caab 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2007,16 +2007,18 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file)
return -1;
}
}
- trace_create_file("filter", 0644, file->dir, file,
- &ftrace_event_filter_fops);
/*
* Only event directories that can be enabled should have
- * triggers.
+ * triggers or filters.
*/
- if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
+ if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) {
+ trace_create_file("filter", 0644, file->dir, file,
+ &ftrace_event_filter_fops);
+
trace_create_file("trigger", 0644, file->dir, file,
&event_trigger_fops);
+ }
#ifdef CONFIG_HIST_TRIGGERS
trace_create_file("hist", 0444, file->dir, file,
--
2.17.0
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* [for-next][PATCH 08/19] tracing: Add trigger file for trace_markers tracefs/ftrace/print
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
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2018-05-29 15:23 ` [for-next][PATCH 07/19] tracing: Do not show filter file for ftrace internal events Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 09/19] tracing: Have zero size length in filter logic be full string Steven Rostedt
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18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel
Cc: Ingo Molnar, Andrew Morton, Tom Zanussi, Clark Williams,
Karim Yaghmour, Brendan Gregg, Joel Fernandes, Namhyung Kim
[-- Attachment #1: 0008-tracing-Add-trigger-file-for-trace_markers-tracefs-f.patch --]
[-- Type: text/plain, Size: 4868 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Allow writing to the trace_markers file initiate triggers defined in
tracefs/ftrace/print/trigger file. This will allow of user space to trigger
the same type of triggers (including histograms) that the trace events use.
Had to create a ftrace_event_register() function that will become the
trace_marker print event's reg() function. This is required because of how
triggers are enabled:
event_trigger_write() {
event_trigger_regex_write() {
trigger_process_regex() {
for p in trigger_commands {
p->func(); /* trigger_snapshot_cmd->func */
event_trigger_callback() {
cmd_ops->reg() /* register_trigger() */ {
trace_event_trigger_enable_disable() {
trace_event_enable_disable() {
call->class->reg();
Without the reg() function, the trigger code will call a NULL pointer and
crash the system.
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Karim Yaghmour <karim.yaghmour@opersys.com>
Cc: Brendan Gregg <bgregg@netflix.com>
Suggested-by: Joel Fernandes <joelaf@google.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace.c | 17 +++++++++++++++++
kernel/trace/trace.h | 1 +
kernel/trace/trace_entries.h | 6 ++++--
kernel/trace/trace_export.c | 7 +++++++
4 files changed, 29 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d5000cba5a27..e69820f77b33 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6074,6 +6074,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
{
struct trace_array *tr = filp->private_data;
struct ring_buffer_event *event;
+ enum event_trigger_type tt = ETT_NONE;
struct ring_buffer *buffer;
struct print_entry *entry;
unsigned long irq_flags;
@@ -6122,6 +6123,12 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
written = cnt;
len = cnt;
+ if (tr->trace_marker_file && !list_empty(&tr->trace_marker_file->triggers)) {
+ /* do not add \n before testing triggers, but add \0 */
+ entry->buf[cnt] = '\0';
+ tt = event_triggers_call(tr->trace_marker_file, entry, event);
+ }
+
if (entry->buf[cnt - 1] != '\n') {
entry->buf[cnt] = '\n';
entry->buf[cnt + 1] = '\0';
@@ -6130,6 +6137,9 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
__buffer_unlock_commit(buffer, event);
+ if (tt)
+ event_triggers_post_call(tr->trace_marker_file, tt);
+
if (written > 0)
*fpos += written;
@@ -7896,6 +7906,7 @@ static __init void create_trace_instances(struct dentry *d_tracer)
static void
init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
{
+ struct trace_event_file *file;
int cpu;
trace_create_file("available_tracers", 0444, d_tracer,
@@ -7928,6 +7939,12 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
trace_create_file("trace_marker", 0220, d_tracer,
tr, &tracing_mark_fops);
+ file = __find_event_file(tr, "ftrace", "print");
+ if (file && file->dir)
+ trace_create_file("trigger", 0644, file->dir, file,
+ &event_trigger_fops);
+ tr->trace_marker_file = file;
+
trace_create_file("trace_marker_raw", 0220, d_tracer,
tr, &tracing_mark_raw_fops);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index d0319cbacf11..630c5a24b2b2 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -259,6 +259,7 @@ struct trace_array {
struct trace_options *topts;
struct list_head systems;
struct list_head events;
+ struct trace_event_file *trace_marker_file;
cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
int ref;
#ifdef CONFIG_FUNCTION_TRACER
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index e3a658bac10f..1d67464ed95e 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -230,7 +230,7 @@ FTRACE_ENTRY(bprint, bprint_entry,
FILTER_OTHER
);
-FTRACE_ENTRY(print, print_entry,
+FTRACE_ENTRY_REG(print, print_entry,
TRACE_PRINT,
@@ -242,7 +242,9 @@ FTRACE_ENTRY(print, print_entry,
F_printk("%ps: %s",
(void *)__entry->ip, __entry->buf),
- FILTER_OTHER
+ FILTER_OTHER,
+
+ ftrace_event_register
);
FTRACE_ENTRY(raw_data, raw_data_entry,
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index d842f1eadfe5..45630a76ed3a 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -14,6 +14,13 @@
#include "trace_output.h"
+/* Stub function for events with triggers */
+static int ftrace_event_register(struct trace_event_call *call,
+ enum trace_reg type, void *data)
+{
+ return 0;
+}
+
#undef TRACE_SYSTEM
#define TRACE_SYSTEM ftrace
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 09/19] tracing: Have zero size length in filter logic be full string
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (7 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 08/19] tracing: Add trigger file for trace_markers tracefs/ftrace/print Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 10/19] tracing: Prevent further users of zero size static arrays in trace events Steven Rostedt
` (9 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0009-tracing-Have-zero-size-length-in-filter-logic-be-ful.patch --]
[-- Type: text/plain, Size: 2055 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
As strings in trace events may not have a nul terminating character, the
filter string compares use the defined string length for the field for the
compares.
The trace_marker records data slightly different than do normal events. It's
size is zero, meaning that the string is the rest of the array, and that the
string also ends with '\0'.
If the size is zero, assume that the string is nul terminated and read the
string in question as is.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace_events_filter.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 7d306b74230f..0171407d231f 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -750,31 +750,32 @@ static int filter_pred_none(struct filter_pred *pred, void *event)
*
* Note:
* - @str might not be NULL-terminated if it's of type DYN_STRING
- * or STATIC_STRING
+ * or STATIC_STRING, unless @len is zero.
*/
static int regex_match_full(char *str, struct regex *r, int len)
{
- if (strncmp(str, r->pattern, len) == 0)
- return 1;
- return 0;
+ /* len of zero means str is dynamic and ends with '\0' */
+ if (!len)
+ return strcmp(str, r->pattern) == 0;
+
+ return strncmp(str, r->pattern, len) == 0;
}
static int regex_match_front(char *str, struct regex *r, int len)
{
- if (len < r->len)
+ if (len && len < r->len)
return 0;
- if (strncmp(str, r->pattern, r->len) == 0)
- return 1;
- return 0;
+ return strncmp(str, r->pattern, r->len) == 0;
}
static int regex_match_middle(char *str, struct regex *r, int len)
{
- if (strnstr(str, r->pattern, len))
- return 1;
- return 0;
+ if (!len)
+ return strstr(str, r->pattern) != NULL;
+
+ return strnstr(str, r->pattern, len) != NULL;
}
static int regex_match_end(char *str, struct regex *r, int len)
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 10/19] tracing: Prevent further users of zero size static arrays in trace events
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (8 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 09/19] tracing: Have zero size length in filter logic be full string Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 11/19] tracing: Allow histogram triggers to access ftrace internal events Steven Rostedt
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18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0010-tracing-Prevent-further-users-of-zero-size-static-ar.patch --]
[-- Type: text/plain, Size: 1159 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
A zero size static array has special meaning in the ftrace infrastructure.
Trace events are for recording data in the trace buffers that is normally
difficult to obtain via probes or function tracing. There is no reason for
any trace event to declare a zero size static array.
If one does, BUILD_BUG_ON() will trigger and prevent the kernel from
compiling.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/trace/trace_events.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h
index bfda803b0a09..4ecdfe2e3580 100644
--- a/include/trace/trace_events.h
+++ b/include/trace/trace_events.h
@@ -422,6 +422,7 @@ static struct trace_event_functions trace_event_type_funcs_##call = { \
do { \
char *type_str = #type"["__stringify(len)"]"; \
BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
+ BUILD_BUG_ON(len <= 0); \
ret = trace_define_field(event_call, type_str, #item, \
offsetof(typeof(field), item), \
sizeof(field.item), \
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 11/19] tracing: Allow histogram triggers to access ftrace internal events
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (9 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 10/19] tracing: Prevent further users of zero size static arrays in trace events Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 12/19] tracing: Document trace_marker triggers Steven Rostedt
` (7 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0011-tracing-Allow-histogram-triggers-to-access-ftrace-in.patch --]
[-- Type: text/plain, Size: 996 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Now that trace_marker can have triggers, including a histogram triggers, the
onmatch() and onmax() access the trace event. To do so, the search routine
to find the event file needs to use the raw __find_event_file() that does
not filter out ftrace events.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace_events_hist.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index b9061ed59bbd..046c716a6536 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -2865,7 +2865,7 @@ static struct trace_event_file *event_file(struct trace_array *tr,
{
struct trace_event_file *file;
- file = find_event_file(tr, system, event_name);
+ file = __find_event_file(tr, system, event_name);
if (!file)
return ERR_PTR(-EINVAL);
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 12/19] tracing: Document trace_marker triggers
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (10 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 11/19] tracing: Allow histogram triggers to access ftrace internal events Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 13/19] ftrace/selftest: Have the reset_trigger code be a bit more careful Steven Rostedt
` (6 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Tom Zanussi, Namhyung Kim
[-- Attachment #1: 0012-tracing-Document-trace_marker-triggers.patch --]
[-- Type: text/plain, Size: 35461 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Add documentation and an example on how to use trace_marker triggers.
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
Documentation/trace/events.rst | 6 +-
Documentation/trace/ftrace.rst | 5 +
Documentation/trace/histogram.txt | 545 +++++++++++++++++++++++++++++-
3 files changed, 554 insertions(+), 2 deletions(-)
diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst
index a5ea2cb0082b..1afae55dc55c 100644
--- a/Documentation/trace/events.rst
+++ b/Documentation/trace/events.rst
@@ -338,10 +338,14 @@ used for conditionally invoking triggers.
The syntax for event triggers is roughly based on the syntax for
set_ftrace_filter 'ftrace filter commands' (see the 'Filter commands'
-section of Documentation/trace/ftrace.txt), but there are major
+section of Documentation/trace/ftrace.rst), but there are major
differences and the implementation isn't currently tied to it in any
way, so beware about making generalizations between the two.
+Note: Writing into trace_marker (See Documentation/trace/ftrace.rst)
+ can also enable triggers that are written into
+ /sys/kernel/tracing/events/ftrace/print/trigger
+
6.1 Expression syntax
---------------------
diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst
index 67d9c38e95eb..aad4776c0f5d 100644
--- a/Documentation/trace/ftrace.rst
+++ b/Documentation/trace/ftrace.rst
@@ -507,6 +507,11 @@ of ftrace. Here is a list of some of the key files:
trace_fd = open("trace_marker", WR_ONLY);
+ Note: Writing into the trace_marker file can also initiate triggers
+ that are written into /sys/kernel/tracing/events/ftrace/print/trigger
+ See "Event triggers" in Documentation/trace/events.rst and an
+ example in Documentation/trace/histogram.rst (Section 3.)
+
trace_marker_raw:
This is similar to trace_marker above, but is meant for for binary data
diff --git a/Documentation/trace/histogram.txt b/Documentation/trace/histogram.txt
index 6e05510afc28..b13771cb12c1 100644
--- a/Documentation/trace/histogram.txt
+++ b/Documentation/trace/histogram.txt
@@ -1604,7 +1604,6 @@
Entries: 7
Dropped: 0
-
2.2 Inter-event hist triggers
-----------------------------
@@ -1993,3 +1992,547 @@ hist trigger specification.
Hits: 12970
Entries: 2
Dropped: 0
+
+3. User space creating a trigger
+--------------------------------
+
+Writing into /sys/kernel/tracing/trace_marker writes into the ftrace
+ring buffer. This can also act like an event, by writing into the trigger
+file located in /sys/kernel/tracing/events/ftrace/print/
+
+Modifying cyclictest to write into the trace_marker file before it sleeps
+and after it wakes up, something like this:
+
+static void traceputs(char *str)
+{
+ /* tracemark_fd is the trace_marker file descriptor */
+ if (tracemark_fd < 0)
+ return;
+ /* write the tracemark message */
+ write(tracemark_fd, str, strlen(str));
+}
+
+And later add something like:
+
+ traceputs("start");
+ clock_nanosleep(...);
+ traceputs("end");
+
+We can make a histogram from this:
+
+ # cd /sys/kernel/tracing
+ # echo 'latency u64 lat' > synthetic_events
+ # echo 'hist:keys=common_pid:ts0=common_timestamp.usecs if buf == "start"' > events/ftrace/print/trigger
+ # echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$ts0:onmatch(ftrace.print).latency($lat) if buf == "end"' >> events/ftrace/print/trigger
+ # echo 'hist:keys=lat,common_pid:sort=lat' > events/synthetic/latency/trigger
+
+The above created a synthetic event called "latency" and two histograms
+against the trace_marker, one gets triggered when "start" is written into the
+trace_marker file and the other when "end" is written. If the pids match, then
+it will call the "latency" synthetic event with the calculated latency as its
+parameter. Finally, a histogram is added to the latency synthetic event to
+record the calculated latency along with the pid.
+
+Now running cyclictest with:
+
+ # ./cyclictest -p80 -d0 -i250 -n -a -t --tracemark -b 1000
+
+ -p80 : run threads at priority 80
+ -d0 : have all threads run at the same interval
+ -i250 : start the interval at 250 microseconds (all threads will do this)
+ -n : sleep with nanosleep
+ -a : affine all threads to a separate CPU
+ -t : one thread per available CPU
+ --tracemark : enable trace mark writing
+ -b 1000 : stop if any latency is greater than 1000 microseconds
+
+Note, the -b 1000 is used just to make --tracemark available.
+
+Then we can see the histogram created by this with:
+
+ # cat events/synthetic/latency/hist
+# event histogram
+#
+# trigger info: hist:keys=lat,common_pid:vals=hitcount:sort=lat:size=2048 [active]
+#
+
+{ lat: 107, common_pid: 2039 } hitcount: 1
+{ lat: 122, common_pid: 2041 } hitcount: 1
+{ lat: 166, common_pid: 2039 } hitcount: 1
+{ lat: 174, common_pid: 2039 } hitcount: 1
+{ lat: 194, common_pid: 2041 } hitcount: 1
+{ lat: 196, common_pid: 2036 } hitcount: 1
+{ lat: 197, common_pid: 2038 } hitcount: 1
+{ lat: 198, common_pid: 2039 } hitcount: 1
+{ lat: 199, common_pid: 2039 } hitcount: 1
+{ lat: 200, common_pid: 2041 } hitcount: 1
+{ lat: 201, common_pid: 2039 } hitcount: 2
+{ lat: 202, common_pid: 2038 } hitcount: 1
+{ lat: 202, common_pid: 2043 } hitcount: 1
+{ lat: 203, common_pid: 2039 } hitcount: 1
+{ lat: 203, common_pid: 2036 } hitcount: 1
+{ lat: 203, common_pid: 2041 } hitcount: 1
+{ lat: 206, common_pid: 2038 } hitcount: 2
+{ lat: 207, common_pid: 2039 } hitcount: 1
+{ lat: 207, common_pid: 2036 } hitcount: 1
+{ lat: 208, common_pid: 2040 } hitcount: 1
+{ lat: 209, common_pid: 2043 } hitcount: 1
+{ lat: 210, common_pid: 2039 } hitcount: 1
+{ lat: 211, common_pid: 2039 } hitcount: 4
+{ lat: 212, common_pid: 2043 } hitcount: 1
+{ lat: 212, common_pid: 2039 } hitcount: 2
+{ lat: 213, common_pid: 2039 } hitcount: 1
+{ lat: 214, common_pid: 2038 } hitcount: 1
+{ lat: 214, common_pid: 2039 } hitcount: 2
+{ lat: 214, common_pid: 2042 } hitcount: 1
+{ lat: 215, common_pid: 2039 } hitcount: 1
+{ lat: 217, common_pid: 2036 } hitcount: 1
+{ lat: 217, common_pid: 2040 } hitcount: 1
+{ lat: 217, common_pid: 2039 } hitcount: 1
+{ lat: 218, common_pid: 2039 } hitcount: 6
+{ lat: 219, common_pid: 2039 } hitcount: 9
+{ lat: 220, common_pid: 2039 } hitcount: 11
+{ lat: 221, common_pid: 2039 } hitcount: 5
+{ lat: 221, common_pid: 2042 } hitcount: 1
+{ lat: 222, common_pid: 2039 } hitcount: 7
+{ lat: 223, common_pid: 2036 } hitcount: 1
+{ lat: 223, common_pid: 2039 } hitcount: 3
+{ lat: 224, common_pid: 2039 } hitcount: 4
+{ lat: 224, common_pid: 2037 } hitcount: 1
+{ lat: 224, common_pid: 2036 } hitcount: 2
+{ lat: 225, common_pid: 2039 } hitcount: 5
+{ lat: 225, common_pid: 2042 } hitcount: 1
+{ lat: 226, common_pid: 2039 } hitcount: 7
+{ lat: 226, common_pid: 2036 } hitcount: 4
+{ lat: 227, common_pid: 2039 } hitcount: 6
+{ lat: 227, common_pid: 2036 } hitcount: 12
+{ lat: 227, common_pid: 2043 } hitcount: 1
+{ lat: 228, common_pid: 2039 } hitcount: 7
+{ lat: 228, common_pid: 2036 } hitcount: 14
+{ lat: 229, common_pid: 2039 } hitcount: 9
+{ lat: 229, common_pid: 2036 } hitcount: 8
+{ lat: 229, common_pid: 2038 } hitcount: 1
+{ lat: 230, common_pid: 2039 } hitcount: 11
+{ lat: 230, common_pid: 2036 } hitcount: 6
+{ lat: 230, common_pid: 2043 } hitcount: 1
+{ lat: 230, common_pid: 2042 } hitcount: 2
+{ lat: 231, common_pid: 2041 } hitcount: 1
+{ lat: 231, common_pid: 2036 } hitcount: 6
+{ lat: 231, common_pid: 2043 } hitcount: 1
+{ lat: 231, common_pid: 2039 } hitcount: 8
+{ lat: 232, common_pid: 2037 } hitcount: 1
+{ lat: 232, common_pid: 2039 } hitcount: 6
+{ lat: 232, common_pid: 2040 } hitcount: 2
+{ lat: 232, common_pid: 2036 } hitcount: 5
+{ lat: 232, common_pid: 2043 } hitcount: 1
+{ lat: 233, common_pid: 2036 } hitcount: 5
+{ lat: 233, common_pid: 2039 } hitcount: 11
+{ lat: 234, common_pid: 2039 } hitcount: 4
+{ lat: 234, common_pid: 2038 } hitcount: 2
+{ lat: 234, common_pid: 2043 } hitcount: 2
+{ lat: 234, common_pid: 2036 } hitcount: 11
+{ lat: 234, common_pid: 2040 } hitcount: 1
+{ lat: 235, common_pid: 2037 } hitcount: 2
+{ lat: 235, common_pid: 2036 } hitcount: 8
+{ lat: 235, common_pid: 2043 } hitcount: 2
+{ lat: 235, common_pid: 2039 } hitcount: 5
+{ lat: 235, common_pid: 2042 } hitcount: 2
+{ lat: 235, common_pid: 2040 } hitcount: 4
+{ lat: 235, common_pid: 2041 } hitcount: 1
+{ lat: 236, common_pid: 2036 } hitcount: 7
+{ lat: 236, common_pid: 2037 } hitcount: 1
+{ lat: 236, common_pid: 2041 } hitcount: 5
+{ lat: 236, common_pid: 2039 } hitcount: 3
+{ lat: 236, common_pid: 2043 } hitcount: 9
+{ lat: 236, common_pid: 2040 } hitcount: 7
+{ lat: 237, common_pid: 2037 } hitcount: 1
+{ lat: 237, common_pid: 2040 } hitcount: 1
+{ lat: 237, common_pid: 2036 } hitcount: 9
+{ lat: 237, common_pid: 2039 } hitcount: 3
+{ lat: 237, common_pid: 2043 } hitcount: 8
+{ lat: 237, common_pid: 2042 } hitcount: 2
+{ lat: 237, common_pid: 2041 } hitcount: 2
+{ lat: 238, common_pid: 2043 } hitcount: 10
+{ lat: 238, common_pid: 2040 } hitcount: 1
+{ lat: 238, common_pid: 2037 } hitcount: 9
+{ lat: 238, common_pid: 2038 } hitcount: 1
+{ lat: 238, common_pid: 2039 } hitcount: 1
+{ lat: 238, common_pid: 2042 } hitcount: 3
+{ lat: 238, common_pid: 2036 } hitcount: 7
+{ lat: 239, common_pid: 2041 } hitcount: 1
+{ lat: 239, common_pid: 2043 } hitcount: 11
+{ lat: 239, common_pid: 2037 } hitcount: 11
+{ lat: 239, common_pid: 2038 } hitcount: 6
+{ lat: 239, common_pid: 2036 } hitcount: 7
+{ lat: 239, common_pid: 2040 } hitcount: 1
+{ lat: 239, common_pid: 2042 } hitcount: 9
+{ lat: 240, common_pid: 2037 } hitcount: 29
+{ lat: 240, common_pid: 2043 } hitcount: 15
+{ lat: 240, common_pid: 2040 } hitcount: 44
+{ lat: 240, common_pid: 2039 } hitcount: 1
+{ lat: 240, common_pid: 2041 } hitcount: 2
+{ lat: 240, common_pid: 2038 } hitcount: 1
+{ lat: 240, common_pid: 2036 } hitcount: 10
+{ lat: 240, common_pid: 2042 } hitcount: 13
+{ lat: 241, common_pid: 2036 } hitcount: 21
+{ lat: 241, common_pid: 2041 } hitcount: 36
+{ lat: 241, common_pid: 2037 } hitcount: 34
+{ lat: 241, common_pid: 2042 } hitcount: 14
+{ lat: 241, common_pid: 2040 } hitcount: 94
+{ lat: 241, common_pid: 2039 } hitcount: 12
+{ lat: 241, common_pid: 2038 } hitcount: 2
+{ lat: 241, common_pid: 2043 } hitcount: 28
+{ lat: 242, common_pid: 2040 } hitcount: 109
+{ lat: 242, common_pid: 2041 } hitcount: 506
+{ lat: 242, common_pid: 2039 } hitcount: 155
+{ lat: 242, common_pid: 2042 } hitcount: 21
+{ lat: 242, common_pid: 2037 } hitcount: 52
+{ lat: 242, common_pid: 2043 } hitcount: 21
+{ lat: 242, common_pid: 2036 } hitcount: 16
+{ lat: 242, common_pid: 2038 } hitcount: 156
+{ lat: 243, common_pid: 2037 } hitcount: 46
+{ lat: 243, common_pid: 2039 } hitcount: 40
+{ lat: 243, common_pid: 2042 } hitcount: 119
+{ lat: 243, common_pid: 2041 } hitcount: 611
+{ lat: 243, common_pid: 2036 } hitcount: 69
+{ lat: 243, common_pid: 2038 } hitcount: 784
+{ lat: 243, common_pid: 2040 } hitcount: 323
+{ lat: 243, common_pid: 2043 } hitcount: 14
+{ lat: 244, common_pid: 2043 } hitcount: 35
+{ lat: 244, common_pid: 2042 } hitcount: 305
+{ lat: 244, common_pid: 2039 } hitcount: 8
+{ lat: 244, common_pid: 2040 } hitcount: 4515
+{ lat: 244, common_pid: 2038 } hitcount: 371
+{ lat: 244, common_pid: 2037 } hitcount: 31
+{ lat: 244, common_pid: 2036 } hitcount: 114
+{ lat: 244, common_pid: 2041 } hitcount: 3396
+{ lat: 245, common_pid: 2036 } hitcount: 700
+{ lat: 245, common_pid: 2041 } hitcount: 2772
+{ lat: 245, common_pid: 2037 } hitcount: 268
+{ lat: 245, common_pid: 2039 } hitcount: 472
+{ lat: 245, common_pid: 2038 } hitcount: 2758
+{ lat: 245, common_pid: 2042 } hitcount: 3833
+{ lat: 245, common_pid: 2040 } hitcount: 3105
+{ lat: 245, common_pid: 2043 } hitcount: 645
+{ lat: 246, common_pid: 2038 } hitcount: 3451
+{ lat: 246, common_pid: 2041 } hitcount: 142
+{ lat: 246, common_pid: 2037 } hitcount: 5101
+{ lat: 246, common_pid: 2040 } hitcount: 68
+{ lat: 246, common_pid: 2043 } hitcount: 5099
+{ lat: 246, common_pid: 2039 } hitcount: 5608
+{ lat: 246, common_pid: 2042 } hitcount: 3723
+{ lat: 246, common_pid: 2036 } hitcount: 4738
+{ lat: 247, common_pid: 2042 } hitcount: 312
+{ lat: 247, common_pid: 2043 } hitcount: 2385
+{ lat: 247, common_pid: 2041 } hitcount: 452
+{ lat: 247, common_pid: 2038 } hitcount: 792
+{ lat: 247, common_pid: 2040 } hitcount: 78
+{ lat: 247, common_pid: 2036 } hitcount: 2375
+{ lat: 247, common_pid: 2039 } hitcount: 1834
+{ lat: 247, common_pid: 2037 } hitcount: 2655
+{ lat: 248, common_pid: 2037 } hitcount: 36
+{ lat: 248, common_pid: 2042 } hitcount: 11
+{ lat: 248, common_pid: 2038 } hitcount: 122
+{ lat: 248, common_pid: 2036 } hitcount: 135
+{ lat: 248, common_pid: 2039 } hitcount: 26
+{ lat: 248, common_pid: 2041 } hitcount: 503
+{ lat: 248, common_pid: 2043 } hitcount: 66
+{ lat: 248, common_pid: 2040 } hitcount: 46
+{ lat: 249, common_pid: 2037 } hitcount: 29
+{ lat: 249, common_pid: 2038 } hitcount: 1
+{ lat: 249, common_pid: 2043 } hitcount: 29
+{ lat: 249, common_pid: 2039 } hitcount: 8
+{ lat: 249, common_pid: 2042 } hitcount: 56
+{ lat: 249, common_pid: 2040 } hitcount: 27
+{ lat: 249, common_pid: 2041 } hitcount: 11
+{ lat: 249, common_pid: 2036 } hitcount: 27
+{ lat: 250, common_pid: 2038 } hitcount: 1
+{ lat: 250, common_pid: 2036 } hitcount: 30
+{ lat: 250, common_pid: 2040 } hitcount: 19
+{ lat: 250, common_pid: 2043 } hitcount: 22
+{ lat: 250, common_pid: 2042 } hitcount: 20
+{ lat: 250, common_pid: 2041 } hitcount: 1
+{ lat: 250, common_pid: 2039 } hitcount: 6
+{ lat: 250, common_pid: 2037 } hitcount: 48
+{ lat: 251, common_pid: 2037 } hitcount: 43
+{ lat: 251, common_pid: 2039 } hitcount: 1
+{ lat: 251, common_pid: 2036 } hitcount: 12
+{ lat: 251, common_pid: 2042 } hitcount: 2
+{ lat: 251, common_pid: 2041 } hitcount: 1
+{ lat: 251, common_pid: 2043 } hitcount: 15
+{ lat: 251, common_pid: 2040 } hitcount: 3
+{ lat: 252, common_pid: 2040 } hitcount: 1
+{ lat: 252, common_pid: 2036 } hitcount: 12
+{ lat: 252, common_pid: 2037 } hitcount: 21
+{ lat: 252, common_pid: 2043 } hitcount: 14
+{ lat: 253, common_pid: 2037 } hitcount: 21
+{ lat: 253, common_pid: 2039 } hitcount: 2
+{ lat: 253, common_pid: 2036 } hitcount: 9
+{ lat: 253, common_pid: 2043 } hitcount: 6
+{ lat: 253, common_pid: 2040 } hitcount: 1
+{ lat: 254, common_pid: 2036 } hitcount: 8
+{ lat: 254, common_pid: 2043 } hitcount: 3
+{ lat: 254, common_pid: 2041 } hitcount: 1
+{ lat: 254, common_pid: 2042 } hitcount: 1
+{ lat: 254, common_pid: 2039 } hitcount: 1
+{ lat: 254, common_pid: 2037 } hitcount: 12
+{ lat: 255, common_pid: 2043 } hitcount: 1
+{ lat: 255, common_pid: 2037 } hitcount: 2
+{ lat: 255, common_pid: 2036 } hitcount: 2
+{ lat: 255, common_pid: 2039 } hitcount: 8
+{ lat: 256, common_pid: 2043 } hitcount: 1
+{ lat: 256, common_pid: 2036 } hitcount: 4
+{ lat: 256, common_pid: 2039 } hitcount: 6
+{ lat: 257, common_pid: 2039 } hitcount: 5
+{ lat: 257, common_pid: 2036 } hitcount: 4
+{ lat: 258, common_pid: 2039 } hitcount: 5
+{ lat: 258, common_pid: 2036 } hitcount: 2
+{ lat: 259, common_pid: 2036 } hitcount: 7
+{ lat: 259, common_pid: 2039 } hitcount: 7
+{ lat: 260, common_pid: 2036 } hitcount: 8
+{ lat: 260, common_pid: 2039 } hitcount: 6
+{ lat: 261, common_pid: 2036 } hitcount: 5
+{ lat: 261, common_pid: 2039 } hitcount: 7
+{ lat: 262, common_pid: 2039 } hitcount: 5
+{ lat: 262, common_pid: 2036 } hitcount: 5
+{ lat: 263, common_pid: 2039 } hitcount: 7
+{ lat: 263, common_pid: 2036 } hitcount: 7
+{ lat: 264, common_pid: 2039 } hitcount: 9
+{ lat: 264, common_pid: 2036 } hitcount: 9
+{ lat: 265, common_pid: 2036 } hitcount: 5
+{ lat: 265, common_pid: 2039 } hitcount: 1
+{ lat: 266, common_pid: 2036 } hitcount: 1
+{ lat: 266, common_pid: 2039 } hitcount: 3
+{ lat: 267, common_pid: 2036 } hitcount: 1
+{ lat: 267, common_pid: 2039 } hitcount: 3
+{ lat: 268, common_pid: 2036 } hitcount: 1
+{ lat: 268, common_pid: 2039 } hitcount: 6
+{ lat: 269, common_pid: 2036 } hitcount: 1
+{ lat: 269, common_pid: 2043 } hitcount: 1
+{ lat: 269, common_pid: 2039 } hitcount: 2
+{ lat: 270, common_pid: 2040 } hitcount: 1
+{ lat: 270, common_pid: 2039 } hitcount: 6
+{ lat: 271, common_pid: 2041 } hitcount: 1
+{ lat: 271, common_pid: 2039 } hitcount: 5
+{ lat: 272, common_pid: 2039 } hitcount: 10
+{ lat: 273, common_pid: 2039 } hitcount: 8
+{ lat: 274, common_pid: 2039 } hitcount: 2
+{ lat: 275, common_pid: 2039 } hitcount: 1
+{ lat: 276, common_pid: 2039 } hitcount: 2
+{ lat: 276, common_pid: 2037 } hitcount: 1
+{ lat: 276, common_pid: 2038 } hitcount: 1
+{ lat: 277, common_pid: 2039 } hitcount: 1
+{ lat: 277, common_pid: 2042 } hitcount: 1
+{ lat: 278, common_pid: 2039 } hitcount: 1
+{ lat: 279, common_pid: 2039 } hitcount: 4
+{ lat: 279, common_pid: 2043 } hitcount: 1
+{ lat: 280, common_pid: 2039 } hitcount: 3
+{ lat: 283, common_pid: 2036 } hitcount: 2
+{ lat: 284, common_pid: 2039 } hitcount: 1
+{ lat: 284, common_pid: 2043 } hitcount: 1
+{ lat: 288, common_pid: 2039 } hitcount: 1
+{ lat: 289, common_pid: 2039 } hitcount: 1
+{ lat: 300, common_pid: 2039 } hitcount: 1
+{ lat: 384, common_pid: 2039 } hitcount: 1
+
+Totals:
+ Hits: 67625
+ Entries: 278
+ Dropped: 0
+
+Note, the writes are around the sleep, so ideally they will all be of 250
+microseconds. If you are wondering how there are several that are under
+250 microseconds, that is because the way cyclictest works, is if one
+iteration comes in late, the next one will set the timer to wake up less that
+250. That is, if an iteration came in 50 microseconds late, the next wake up
+will be at 200 microseconds.
+
+But this could easily be done in userspace. To make this even more
+interesting, we can mix the histogram between events that happened in the
+kernel with trace_marker.
+
+ # cd /sys/kernel/tracing
+ # echo 'latency u64 lat' > synthetic_events
+ # echo 'hist:keys=pid:ts0=common_timestamp.usecs' > events/sched/sched_waking/trigger
+ # echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_waking).latency($lat) if buf == "end"' > events/ftrace/print/trigger
+ # echo 'hist:keys=lat,common_pid:sort=lat' > events/synthetic/latency/trigger
+
+The difference this time is that instead of using the trace_marker to start
+the latency, the sched_waking event is used, matching the common_pid for the
+trace_marker write with the pid that is being woken by sched_waking.
+
+After running cyclictest again with the same parameters, we now have:
+
+ # cat events/synthetic/latency/hist
+# event histogram
+#
+# trigger info: hist:keys=lat,common_pid:vals=hitcount:sort=lat:size=2048 [active]
+#
+
+{ lat: 7, common_pid: 2302 } hitcount: 640
+{ lat: 7, common_pid: 2299 } hitcount: 42
+{ lat: 7, common_pid: 2303 } hitcount: 18
+{ lat: 7, common_pid: 2305 } hitcount: 166
+{ lat: 7, common_pid: 2306 } hitcount: 1
+{ lat: 7, common_pid: 2301 } hitcount: 91
+{ lat: 7, common_pid: 2300 } hitcount: 17
+{ lat: 8, common_pid: 2303 } hitcount: 8296
+{ lat: 8, common_pid: 2304 } hitcount: 6864
+{ lat: 8, common_pid: 2305 } hitcount: 9464
+{ lat: 8, common_pid: 2301 } hitcount: 9213
+{ lat: 8, common_pid: 2306 } hitcount: 6246
+{ lat: 8, common_pid: 2302 } hitcount: 8797
+{ lat: 8, common_pid: 2299 } hitcount: 8771
+{ lat: 8, common_pid: 2300 } hitcount: 8119
+{ lat: 9, common_pid: 2305 } hitcount: 1519
+{ lat: 9, common_pid: 2299 } hitcount: 2346
+{ lat: 9, common_pid: 2303 } hitcount: 2841
+{ lat: 9, common_pid: 2301 } hitcount: 1846
+{ lat: 9, common_pid: 2304 } hitcount: 3861
+{ lat: 9, common_pid: 2302 } hitcount: 1210
+{ lat: 9, common_pid: 2300 } hitcount: 2762
+{ lat: 9, common_pid: 2306 } hitcount: 4247
+{ lat: 10, common_pid: 2299 } hitcount: 16
+{ lat: 10, common_pid: 2306 } hitcount: 333
+{ lat: 10, common_pid: 2303 } hitcount: 16
+{ lat: 10, common_pid: 2304 } hitcount: 168
+{ lat: 10, common_pid: 2302 } hitcount: 240
+{ lat: 10, common_pid: 2301 } hitcount: 28
+{ lat: 10, common_pid: 2300 } hitcount: 95
+{ lat: 10, common_pid: 2305 } hitcount: 18
+{ lat: 11, common_pid: 2303 } hitcount: 5
+{ lat: 11, common_pid: 2305 } hitcount: 8
+{ lat: 11, common_pid: 2306 } hitcount: 221
+{ lat: 11, common_pid: 2302 } hitcount: 76
+{ lat: 11, common_pid: 2304 } hitcount: 26
+{ lat: 11, common_pid: 2300 } hitcount: 125
+{ lat: 11, common_pid: 2299 } hitcount: 2
+{ lat: 12, common_pid: 2305 } hitcount: 3
+{ lat: 12, common_pid: 2300 } hitcount: 6
+{ lat: 12, common_pid: 2306 } hitcount: 90
+{ lat: 12, common_pid: 2302 } hitcount: 4
+{ lat: 12, common_pid: 2303 } hitcount: 1
+{ lat: 12, common_pid: 2304 } hitcount: 122
+{ lat: 13, common_pid: 2300 } hitcount: 12
+{ lat: 13, common_pid: 2301 } hitcount: 1
+{ lat: 13, common_pid: 2306 } hitcount: 32
+{ lat: 13, common_pid: 2302 } hitcount: 5
+{ lat: 13, common_pid: 2305 } hitcount: 1
+{ lat: 13, common_pid: 2303 } hitcount: 1
+{ lat: 13, common_pid: 2304 } hitcount: 61
+{ lat: 14, common_pid: 2303 } hitcount: 4
+{ lat: 14, common_pid: 2306 } hitcount: 5
+{ lat: 14, common_pid: 2305 } hitcount: 4
+{ lat: 14, common_pid: 2304 } hitcount: 62
+{ lat: 14, common_pid: 2302 } hitcount: 19
+{ lat: 14, common_pid: 2300 } hitcount: 33
+{ lat: 14, common_pid: 2299 } hitcount: 1
+{ lat: 14, common_pid: 2301 } hitcount: 4
+{ lat: 15, common_pid: 2305 } hitcount: 1
+{ lat: 15, common_pid: 2302 } hitcount: 25
+{ lat: 15, common_pid: 2300 } hitcount: 11
+{ lat: 15, common_pid: 2299 } hitcount: 5
+{ lat: 15, common_pid: 2301 } hitcount: 1
+{ lat: 15, common_pid: 2304 } hitcount: 8
+{ lat: 15, common_pid: 2303 } hitcount: 1
+{ lat: 15, common_pid: 2306 } hitcount: 6
+{ lat: 16, common_pid: 2302 } hitcount: 31
+{ lat: 16, common_pid: 2306 } hitcount: 3
+{ lat: 16, common_pid: 2300 } hitcount: 5
+{ lat: 17, common_pid: 2302 } hitcount: 6
+{ lat: 17, common_pid: 2303 } hitcount: 1
+{ lat: 18, common_pid: 2304 } hitcount: 1
+{ lat: 18, common_pid: 2302 } hitcount: 8
+{ lat: 18, common_pid: 2299 } hitcount: 1
+{ lat: 18, common_pid: 2301 } hitcount: 1
+{ lat: 19, common_pid: 2303 } hitcount: 4
+{ lat: 19, common_pid: 2304 } hitcount: 5
+{ lat: 19, common_pid: 2302 } hitcount: 4
+{ lat: 19, common_pid: 2299 } hitcount: 3
+{ lat: 19, common_pid: 2306 } hitcount: 1
+{ lat: 19, common_pid: 2300 } hitcount: 4
+{ lat: 19, common_pid: 2305 } hitcount: 5
+{ lat: 20, common_pid: 2299 } hitcount: 2
+{ lat: 20, common_pid: 2302 } hitcount: 3
+{ lat: 20, common_pid: 2305 } hitcount: 1
+{ lat: 20, common_pid: 2300 } hitcount: 2
+{ lat: 20, common_pid: 2301 } hitcount: 2
+{ lat: 20, common_pid: 2303 } hitcount: 3
+{ lat: 21, common_pid: 2305 } hitcount: 1
+{ lat: 21, common_pid: 2299 } hitcount: 5
+{ lat: 21, common_pid: 2303 } hitcount: 4
+{ lat: 21, common_pid: 2302 } hitcount: 7
+{ lat: 21, common_pid: 2300 } hitcount: 1
+{ lat: 21, common_pid: 2301 } hitcount: 5
+{ lat: 21, common_pid: 2304 } hitcount: 2
+{ lat: 22, common_pid: 2302 } hitcount: 5
+{ lat: 22, common_pid: 2303 } hitcount: 1
+{ lat: 22, common_pid: 2306 } hitcount: 3
+{ lat: 22, common_pid: 2301 } hitcount: 2
+{ lat: 22, common_pid: 2300 } hitcount: 1
+{ lat: 22, common_pid: 2299 } hitcount: 1
+{ lat: 22, common_pid: 2305 } hitcount: 1
+{ lat: 22, common_pid: 2304 } hitcount: 1
+{ lat: 23, common_pid: 2299 } hitcount: 1
+{ lat: 23, common_pid: 2306 } hitcount: 2
+{ lat: 23, common_pid: 2302 } hitcount: 6
+{ lat: 24, common_pid: 2302 } hitcount: 3
+{ lat: 24, common_pid: 2300 } hitcount: 1
+{ lat: 24, common_pid: 2306 } hitcount: 2
+{ lat: 24, common_pid: 2305 } hitcount: 1
+{ lat: 24, common_pid: 2299 } hitcount: 1
+{ lat: 25, common_pid: 2300 } hitcount: 1
+{ lat: 25, common_pid: 2302 } hitcount: 4
+{ lat: 26, common_pid: 2302 } hitcount: 2
+{ lat: 27, common_pid: 2305 } hitcount: 1
+{ lat: 27, common_pid: 2300 } hitcount: 1
+{ lat: 27, common_pid: 2302 } hitcount: 3
+{ lat: 28, common_pid: 2306 } hitcount: 1
+{ lat: 28, common_pid: 2302 } hitcount: 4
+{ lat: 29, common_pid: 2302 } hitcount: 1
+{ lat: 29, common_pid: 2300 } hitcount: 2
+{ lat: 29, common_pid: 2306 } hitcount: 1
+{ lat: 29, common_pid: 2304 } hitcount: 1
+{ lat: 30, common_pid: 2302 } hitcount: 4
+{ lat: 31, common_pid: 2302 } hitcount: 6
+{ lat: 32, common_pid: 2302 } hitcount: 1
+{ lat: 33, common_pid: 2299 } hitcount: 1
+{ lat: 33, common_pid: 2302 } hitcount: 3
+{ lat: 34, common_pid: 2302 } hitcount: 2
+{ lat: 35, common_pid: 2302 } hitcount: 1
+{ lat: 35, common_pid: 2304 } hitcount: 1
+{ lat: 36, common_pid: 2302 } hitcount: 4
+{ lat: 37, common_pid: 2302 } hitcount: 6
+{ lat: 38, common_pid: 2302 } hitcount: 2
+{ lat: 39, common_pid: 2302 } hitcount: 2
+{ lat: 39, common_pid: 2304 } hitcount: 1
+{ lat: 40, common_pid: 2304 } hitcount: 2
+{ lat: 40, common_pid: 2302 } hitcount: 5
+{ lat: 41, common_pid: 2304 } hitcount: 1
+{ lat: 41, common_pid: 2302 } hitcount: 8
+{ lat: 42, common_pid: 2302 } hitcount: 6
+{ lat: 42, common_pid: 2304 } hitcount: 1
+{ lat: 43, common_pid: 2302 } hitcount: 3
+{ lat: 43, common_pid: 2304 } hitcount: 4
+{ lat: 44, common_pid: 2302 } hitcount: 6
+{ lat: 45, common_pid: 2302 } hitcount: 5
+{ lat: 46, common_pid: 2302 } hitcount: 5
+{ lat: 47, common_pid: 2302 } hitcount: 7
+{ lat: 48, common_pid: 2301 } hitcount: 1
+{ lat: 48, common_pid: 2302 } hitcount: 9
+{ lat: 49, common_pid: 2302 } hitcount: 3
+{ lat: 50, common_pid: 2302 } hitcount: 1
+{ lat: 50, common_pid: 2301 } hitcount: 1
+{ lat: 51, common_pid: 2302 } hitcount: 2
+{ lat: 51, common_pid: 2301 } hitcount: 1
+{ lat: 61, common_pid: 2302 } hitcount: 1
+{ lat: 110, common_pid: 2302 } hitcount: 1
+
+Totals:
+ Hits: 89565
+ Entries: 158
+ Dropped: 0
+
+This doesn't tell us any information about how late cyclictest may have
+woken up, but it does show us a nice histogram of how long it took from
+the time that cyclictest was woken to the time it made it into user space.
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 13/19] ftrace/selftest: Have the reset_trigger code be a bit more careful
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (11 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 12/19] tracing: Document trace_marker triggers Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 14/19] ftrace/selftest: Fix reset_trigger() to handle triggers with filters Steven Rostedt
` (5 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel
Cc: Ingo Molnar, Andrew Morton, stable, Namhyung Kim, Masami Hiramatsu
[-- Attachment #1: 0013-ftrace-selftest-Have-the-reset_trigger-code-be-a-bit.patch --]
[-- Type: text/plain, Size: 2116 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
The trigger code is picky in how it can be disabled as there may be
dependencies between different events and synthetic events. Change the order
on how triggers are reset.
1) Reset triggers of all synthetic events first
2) Remove triggers with actions attached to them
3) Remove all other triggers
If this order isn't followed, then some triggers will not be reset, and an
error may happen because a trigger is busy.
Cc: stable@vger.kernel.org
Fixes: cfa0963dc474f ("kselftests/ftrace : Add event trigger testcases")
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
.../testing/selftests/ftrace/test.d/functions | 21 ++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions
index 2a4f16fc9819..8393b1c06027 100644
--- a/tools/testing/selftests/ftrace/test.d/functions
+++ b/tools/testing/selftests/ftrace/test.d/functions
@@ -15,14 +15,29 @@ reset_tracer() { # reset the current tracer
echo nop > current_tracer
}
-reset_trigger() { # reset all current setting triggers
- grep -v ^# events/*/*/trigger |
+reset_trigger_file() {
+ # remove action triggers first
+ grep -H ':on[^:]*(' $@ |
+ while read line; do
+ cmd=`echo $line | cut -f2- -d: | cut -f1 -d" "`
+ file=`echo $line | cut -f1 -d:`
+ echo "!$cmd" >> $file
+ done
+ grep -Hv ^# $@ |
while read line; do
cmd=`echo $line | cut -f2- -d: | cut -f1 -d" "`
- echo "!$cmd" > `echo $line | cut -f1 -d:`
+ file=`echo $line | cut -f1 -d:`
+ echo "!$cmd" > $file
done
}
+reset_trigger() { # reset all current setting triggers
+ if [ -d events/synthetic ]; then
+ reset_trigger_file events/synthetic/*/trigger
+ fi
+ reset_trigger_file events/*/*/trigger
+}
+
reset_events_filter() { # reset all current setting filters
grep -v ^none events/*/*/filter |
while read line; do
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 14/19] ftrace/selftest: Fix reset_trigger() to handle triggers with filters
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (12 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 13/19] ftrace/selftest: Have the reset_trigger code be a bit more careful Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 15/19] tracing/selftest: Add selftests to test trace_marker histogram triggers Steven Rostedt
` (4 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Masami Hiramatsu, Namhyung Kim
[-- Attachment #1: 0014-ftrace-selftest-Fix-reset_trigger-to-handle-triggers.patch --]
[-- Type: text/plain, Size: 2671 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
The reset_trigger() function breaks up the command by a space ' '. This is
useful to ignore the '[active]' word for triggers when removing them. But if
the trigger has a filter (ie. "if prio < 10") then the filter needs to be
attached to the line that is written into the trigger file to remove it. But
the truncation removes the filter and the triggers are not cleared properly.
Before, reset_trigger() did this:
# echo 'hist:keys=common_pid if prev_prio < 10' > events/sched/sched_switch/trigger
# echo 'hist:keys=common_pid if next_prio < 10' >> events/sched/sched_switch/trigger
# cat events/sched/sched_switch/trigger
hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048 if prev_prio < 10 [active]
hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048 if next_prio < 10 [active]
reset_trigger() {
echo '!hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048' >> events/sched/sched_switch/trigger
}
# cat events/sched/sched_switch/trigger
hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048 if prev_prio < 10 [active]
hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048 if next_prio < 10 [active]
After, where it includes the filter:
reset_trigger() {
echo '!hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048 if prev_prio < 10' >> events/sched/sched_switch/trigger
}
# cat events/sched/sched_switch/trigger
hist:keys=common_pid:vals=hitcount:sort=hitcount:size=2048 if next_prio < 10 [active]
Fixes: cfa0963dc474f ("kselftests/ftrace : Add event trigger testcases")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
tools/testing/selftests/ftrace/test.d/functions | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions
index 8393b1c06027..e4645d5e3126 100644
--- a/tools/testing/selftests/ftrace/test.d/functions
+++ b/tools/testing/selftests/ftrace/test.d/functions
@@ -19,13 +19,13 @@ reset_trigger_file() {
# remove action triggers first
grep -H ':on[^:]*(' $@ |
while read line; do
- cmd=`echo $line | cut -f2- -d: | cut -f1 -d" "`
+ cmd=`echo $line | cut -f2- -d: | cut -f1 -d"["`
file=`echo $line | cut -f1 -d:`
echo "!$cmd" >> $file
done
grep -Hv ^# $@ |
while read line; do
- cmd=`echo $line | cut -f2- -d: | cut -f1 -d" "`
+ cmd=`echo $line | cut -f2- -d: | cut -f1 -d"["`
file=`echo $line | cut -f1 -d:`
echo "!$cmd" > $file
done
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 15/19] tracing/selftest: Add selftests to test trace_marker histogram triggers
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (13 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 14/19] ftrace/selftest: Fix reset_trigger() to handle triggers with filters Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 16/19] tracing/selftest: Add test to test hist trigger between kernel event and trace_marker Steven Rostedt
` (3 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Masami Hiramatsu, Namhyung Kim
[-- Attachment #1: 0015-tracing-selftest-Add-selftests-to-test-trace_marker-.patch --]
[-- Type: text/plain, Size: 4240 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Add a couple of tests that test the trace_marker histogram triggers.
One does a straight histogram test, the other will create a synthetic event
and test the latency between two different writes (using filters to
differentiate between them).
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
.../trigger/trigger-trace-marker-hist.tc | 49 ++++++++++++++
.../trigger/trigger-trace-marker-synthetic.tc | 66 +++++++++++++++++++
2 files changed, 115 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
new file mode 100644
index 000000000000..2acbfe2c0c0c
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-hist.tc
@@ -0,0 +1,49 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: trace_marker trigger - test histogram trigger
+# flags: instance
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit_fail
+}
+
+if [ ! -f set_event ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -d events/ftrace/print ]; then
+ echo "event trace_marker is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/hist ]; then
+ echo "hist trigger is not supported"
+ exit_unsupported
+fi
+
+do_reset
+
+echo "Test histogram trace_marker tigger"
+
+echo 'hist:keys=common_pid' > events/ftrace/print/trigger
+for i in `seq 1 10` ; do echo "hello" > trace_marker; done
+grep 'hitcount: *10$' events/ftrace/print/hist > /dev/null || \
+ fail "hist trigger did not trigger correct times on trace_marker"
+
+do_reset
+
+exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc
new file mode 100644
index 000000000000..3666dd6ab02a
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic.tc
@@ -0,0 +1,66 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: trace_marker trigger - test histogram with synthetic event
+# flags:
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ echo > synthetic_events
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit_fail
+}
+
+if [ ! -f set_event ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f synthetic_events ]; then
+ echo "synthetic events not supported"
+ exit_unsupported
+fi
+
+if [ ! -d events/ftrace/print ]; then
+ echo "event trace_marker is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/hist ]; then
+ echo "hist trigger is not supported"
+ exit_unsupported
+fi
+
+do_reset
+
+echo "Test histogram trace_marker to trace_marker latency histogram trigger"
+
+echo 'latency u64 lat' > synthetic_events
+echo 'hist:keys=common_pid:ts0=common_timestamp.usecs if buf == "start"' > events/ftrace/print/trigger
+echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$ts0:onmatch(ftrace.print).latency($lat) if buf == "end"' >> events/ftrace/print/trigger
+echo 'hist:keys=common_pid,lat:sort=lat' > events/synthetic/latency/trigger
+echo -n "start" > trace_marker
+echo -n "end" > trace_marker
+
+cnt=`grep 'hitcount: *1$' events/ftrace/print/hist | wc -l`
+
+if [ $cnt -ne 2 ]; then
+ fail "hist trace_marker trigger did not trigger correctly"
+fi
+
+grep 'hitcount: *1$' events/synthetic/latency/hist > /dev/null || \
+ fail "hist trigger did not trigger "
+
+do_reset
+
+exit 0
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 16/19] tracing/selftest: Add test to test hist trigger between kernel event and trace_marker
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (14 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 15/19] tracing/selftest: Add selftests to test trace_marker histogram triggers Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 17/19] tracing/selftest: Add test to test simple snapshot trigger for trace_marker Steven Rostedt
` (2 subsequent siblings)
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Masami Hiramatsu, Namhyung Kim
[-- Attachment #1: 0016-tracing-selftest-Add-test-to-test-hist-trigger-betwe.patch --]
[-- Type: text/plain, Size: 2676 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Add a test that tests a trigger that is initiated by a kernel event
(sched_waking) and compared to a write to the trace_marker.
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
.../trigger-trace-marker-synthetic-kernel.tc | 68 +++++++++++++++++++
1 file changed, 68 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic-kernel.tc
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic-kernel.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic-kernel.tc
new file mode 100644
index 000000000000..0a69c5d1cda8
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-synthetic-kernel.tc
@@ -0,0 +1,68 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: trace_marker trigger - test histogram with synthetic event against kernel event
+# flags:
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ echo > synthetic_events
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit_fail
+}
+
+if [ ! -f set_event ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f synthetic_events ]; then
+ echo "synthetic events not supported"
+ exit_unsupported
+fi
+
+if [ ! -d events/ftrace/print ]; then
+ echo "event trace_marker is not supported"
+ exit_unsupported
+fi
+
+if [ ! -d events/sched/sched_waking ]; then
+ echo "event sched_waking is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/hist ]; then
+ echo "hist trigger is not supported"
+ exit_unsupported
+fi
+
+do_reset
+
+echo "Test histogram kernel event to trace_marker latency histogram trigger"
+
+echo 'latency u64 lat' > synthetic_events
+echo 'hist:keys=pid:ts0=common_timestamp.usecs' > events/sched/sched_waking/trigger
+echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_waking).latency($lat)' > events/ftrace/print/trigger
+echo 'hist:keys=common_pid,lat:sort=lat' > events/synthetic/latency/trigger
+sleep 1
+echo "hello" > trace_marker
+
+grep 'hitcount: *1$' events/ftrace/print/hist > /dev/null || \
+ fail "hist trigger did not trigger correct times on trace_marker"
+
+grep 'hitcount: *1$' events/synthetic/latency/hist > /dev/null || \
+ fail "hist trigger did not trigger "
+
+do_reset
+
+exit 0
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 17/19] tracing/selftest: Add test to test simple snapshot trigger for trace_marker
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (15 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 16/19] tracing/selftest: Add test to test hist trigger between kernel event and trace_marker Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 18/19] ring-buffer: Fix a bunch of typos in comments Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 19/19] ring-buffer: Fix typo in comment Steven Rostedt
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Masami Hiramatsu
[-- Attachment #1: 0017-tracing-selftest-Add-test-to-test-simple-snapshot-tr.patch --]
[-- Type: text/plain, Size: 2343 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Several complex trigger tests were added for trace_marker, but not a simple
one. This could be used to help diagnose a problem with the code by giving a
reference between how complex a trigger is that fails.
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
.../trigger/trigger-trace-marker-snapshot.tc | 74 +++++++++++++++++++
1 file changed, 74 insertions(+)
create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
new file mode 100644
index 000000000000..6748e8cb42d0
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
@@ -0,0 +1,74 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: trace_marker trigger - test snapshot trigger
+# flags: instance
+
+do_reset() {
+ reset_trigger
+ echo > set_event
+ echo 0 > snapshot
+ clear_trace
+}
+
+fail() { #msg
+ do_reset
+ echo $1
+ exit_fail
+}
+
+if [ ! -f set_event ]; then
+ echo "event tracing is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f snapshot ]; then
+ echo "snapshot is not supported"
+ exit_unsupported
+fi
+
+if [ ! -d events/ftrace/print ]; then
+ echo "event trace_marker is not supported"
+ exit_unsupported
+fi
+
+if [ ! -f events/ftrace/print/trigger ]; then
+ echo "event trigger is not supported"
+ exit_unsupported
+fi
+
+test_trace() {
+ file=$1
+ x=$2
+
+ cat $file | while read line; do
+ comment=`echo $line | sed -e 's/^#//'`
+ if [ "$line" != "$comment" ]; then
+ continue
+ fi
+ echo "testing $line for >$x<"
+ match=`echo $line | sed -e "s/>$x<//"`
+ if [ "$line" == "$match" ]; then
+ fail "$line does not have >$x< in it"
+ fi
+ let x=$x+2
+ done
+}
+
+do_reset
+
+echo "Test snapshot trace_marker tigger"
+
+echo 'snapshot' > events/ftrace/print/trigger
+
+# make sure the snapshot is allocated
+
+grep -q 'Snapshot is allocated' snapshot
+
+for i in `seq 1 10` ; do echo "hello >$i<" > trace_marker; done
+
+test_trace trace 1
+test_trace snapshot 2
+
+do_reset
+
+exit 0
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 18/19] ring-buffer: Fix a bunch of typos in comments
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (16 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 17/19] tracing/selftest: Add test to test simple snapshot trigger for trace_marker Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 19/19] ring-buffer: Fix typo in comment Steven Rostedt
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, One-of-those-commiters
[-- Attachment #1: 0018-ring-buffer-Fix-a-bunch-of-typos-in-comments.patch --]
[-- Type: text/plain, Size: 4536 bytes --]
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
An anonymous source sent me a bunch of typo fixes in the comments of
ring_buffer.c file. That source did not want to be associated to this patch
because they don't want to be known as "one of those" commiters (you know who
you are!). They gave me permission to sign this off in my own name.
Suggested-by: One-of-those-commiters@YouKnowWhoYouAre.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/ring_buffer.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index c9cb9767d49b..6a46af21765c 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -809,7 +809,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp);
*
* You can see, it is legitimate for the previous pointer of
* the head (or any page) not to point back to itself. But only
- * temporarially.
+ * temporarily.
*/
#define RB_PAGE_NORMAL 0UL
@@ -906,7 +906,7 @@ static void rb_list_head_clear(struct list_head *list)
}
/*
- * rb_head_page_dactivate - clears head page ptr (for free list)
+ * rb_head_page_deactivate - clears head page ptr (for free list)
*/
static void
rb_head_page_deactivate(struct ring_buffer_per_cpu *cpu_buffer)
@@ -1780,7 +1780,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
put_online_cpus();
} else {
- /* Make sure this CPU has been intitialized */
+ /* Make sure this CPU has been initialized */
if (!cpumask_test_cpu(cpu_id, buffer->cpumask))
goto out;
@@ -2325,7 +2325,7 @@ rb_update_event(struct ring_buffer_per_cpu *cpu_buffer,
/*
* If we need to add a timestamp, then we
- * add it to the start of the resevered space.
+ * add it to the start of the reserved space.
*/
if (unlikely(info->add_timestamp)) {
bool abs = ring_buffer_time_stamp_abs(cpu_buffer->buffer);
@@ -2681,7 +2681,7 @@ trace_recursive_unlock(struct ring_buffer_per_cpu *cpu_buffer)
* ring_buffer_nest_start - Allow to trace while nested
* @buffer: The ring buffer to modify
*
- * The ring buffer has a safty mechanism to prevent recursion.
+ * The ring buffer has a safety mechanism to prevent recursion.
* But there may be a case where a trace needs to be done while
* tracing something else. In this case, calling this function
* will allow this function to nest within a currently active
@@ -2699,7 +2699,7 @@ void ring_buffer_nest_start(struct ring_buffer *buffer)
preempt_disable_notrace();
cpu = raw_smp_processor_id();
cpu_buffer = buffer->buffers[cpu];
- /* This is the shift value for the above recusive locking */
+ /* This is the shift value for the above recursive locking */
cpu_buffer->nest += NESTED_BITS;
}
@@ -2718,7 +2718,7 @@ void ring_buffer_nest_end(struct ring_buffer *buffer)
/* disabled by ring_buffer_nest_start() */
cpu = raw_smp_processor_id();
cpu_buffer = buffer->buffers[cpu];
- /* This is the shift value for the above recusive locking */
+ /* This is the shift value for the above recursive locking */
cpu_buffer->nest -= NESTED_BITS;
preempt_enable_notrace();
}
@@ -2907,7 +2907,7 @@ rb_reserve_next_event(struct ring_buffer *buffer,
* @buffer: the ring buffer to reserve from
* @length: the length of the data to reserve (excluding event header)
*
- * Returns a reseverd event on the ring buffer to copy directly to.
+ * Returns a reserved event on the ring buffer to copy directly to.
* The user of this interface will need to get the body to write into
* and can use the ring_buffer_event_data() interface.
*
@@ -3009,7 +3009,7 @@ rb_decrement_entry(struct ring_buffer_per_cpu *cpu_buffer,
* This function lets the user discard an event in the ring buffer
* and then that event will not be read later.
*
- * This function only works if it is called before the the item has been
+ * This function only works if it is called before the item has been
* committed. It will try to free the event from the ring buffer
* if another event has not been added behind it.
*
@@ -4127,7 +4127,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_consume);
* through the buffer. Memory is allocated, buffer recording
* is disabled, and the iterator pointer is returned to the caller.
*
- * Disabling buffer recordng prevents the reading from being
+ * Disabling buffer recording prevents the reading from being
* corrupted. This is not a consuming read, so a producer is not
* expected.
*
--
2.17.0
^ permalink raw reply related [flat|nested] 20+ messages in thread
* [for-next][PATCH 19/19] ring-buffer: Fix typo in comment
2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
` (17 preceding siblings ...)
2018-05-29 15:23 ` [for-next][PATCH 18/19] ring-buffer: Fix a bunch of typos in comments Steven Rostedt
@ 2018-05-29 15:23 ` Steven Rostedt
18 siblings, 0 replies; 20+ messages in thread
From: Steven Rostedt @ 2018-05-29 15:23 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Vasyl Gomonovych
[-- Attachment #1: 0019-ring-buffer-Fix-typo-in-comment.patch --]
[-- Type: text/plain, Size: 1032 bytes --]
From: Vasyl Gomonovych <gomonovych@gmail.com>
Fix typo of the word 'been'
Link: http://lkml.kernel.org/r/20180518203130.2011-1-gomonovych@gmail.com
Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/ring_buffer.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index a0233edc0718..b72ebdff0b77 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -65,7 +65,7 @@ u64 ring_buffer_event_time_stamp(struct ring_buffer_event *event);
/*
* ring_buffer_discard_commit will remove an event that has not
- * ben committed yet. If this is used, then ring_buffer_unlock_commit
+ * been committed yet. If this is used, then ring_buffer_unlock_commit
* must not be called on the discarded event. This function
* will try to remove the event from the ring buffer completely
* if another event has not been written after it.
--
2.17.0
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2018-05-29 15:23 [for-next][PATCH 00/19] tracing: Updates for 4.18 Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 01/19] trace: Use -mcount-record for dynamic ftrace Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 02/19] tracepoints: Fix the descriptions of tracepoint_probe_register{_prio} Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 03/19] tracing: Do not reference event data in post call triggers Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 04/19] tracing: Add __find_event_file() to find event files without restrictions Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 05/19] tracing: Have event_trace_init() called by trace_init_tracefs() Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 06/19] tracing: Add brackets in ftrace event dynamic arrays Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 07/19] tracing: Do not show filter file for ftrace internal events Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 08/19] tracing: Add trigger file for trace_markers tracefs/ftrace/print Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 09/19] tracing: Have zero size length in filter logic be full string Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 10/19] tracing: Prevent further users of zero size static arrays in trace events Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 11/19] tracing: Allow histogram triggers to access ftrace internal events Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 12/19] tracing: Document trace_marker triggers Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 13/19] ftrace/selftest: Have the reset_trigger code be a bit more careful Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 14/19] ftrace/selftest: Fix reset_trigger() to handle triggers with filters Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 15/19] tracing/selftest: Add selftests to test trace_marker histogram triggers Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 16/19] tracing/selftest: Add test to test hist trigger between kernel event and trace_marker Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 17/19] tracing/selftest: Add test to test simple snapshot trigger for trace_marker Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 18/19] ring-buffer: Fix a bunch of typos in comments Steven Rostedt
2018-05-29 15:23 ` [for-next][PATCH 19/19] ring-buffer: Fix typo in comment Steven Rostedt
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