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  1. 30 Jan, 2013 1 commit
  3. 13 Feb, 2012 1 commit
  5. 09 Mar, 2011 1 commit
    • David Sharp's avatar
      tracing: Add an 'overwrite' trace_option. · 750912fa
      David Sharp authored 
      

Add an "overwrite" trace_option for ftrace to control whether the buffer should
be overwritten on overflow or not. The default remains to overwrite old events
when the buffer is full. This patch adds the option to instead discard newest
events when the buffer is full. This is useful to get a snapshot of traces just
after enabling traces. Dropping the current event is also a simpler code path.

Signed-off-by: default avatarDavid Sharp <dhsharp@google.com>
LKML-Reference: <1291844807-15481-1-git-send-email-dhsharp@google.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      750912fa
  7. 08 Feb, 2011 2 commits
  9. 27 Apr, 2010 1 commit
  11. 21 Apr, 2010 1 commit
    • Frederic Weisbecker's avatar
      tracing: Dump either the oops's cpu source or all cpus buffers · cecbca96
      Frederic Weisbecker authored 
      

The ftrace_dump_on_oops kernel parameter, sysctl and sysrq let one
dump every cpu buffers when an oops or panic happens.

It's nice when you have few cpus but it may take ages if have many,
plus you miss the real origin of the problem in all the cpu traces.

Sometimes, all you need is to dump the cpu buffer that triggered the
opps, most of the time it is our main interest.

This patch modifies ftrace_dump_on_oops to handle this choice.

The ftrace_dump_on_oops kernel parameter, when it comes alone, has
the same behaviour than before. But ftrace_dump_on_oops=orig_cpu
will only dump the buffer of the cpu that oops'ed.

Similarly, sysctl kernel.ftrace_dump_on_oops=1 and
echo 1 > /proc/sys/kernel/ftrace_dump_on_oops keep their previous
behaviour. But setting 2 jumps into cpu origin dump mode.

v2: Fix double setup
v3: Fix spelling issues reported by Randy Dunlap
v4: Also update __ftrace_dump in the selftests

Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      cecbca96
  13. 09 Feb, 2010 1 commit
  15. 26 Jan, 2010 1 commit
  17. 24 Oct, 2009 1 commit
  19. 21 Sep, 2009 1 commit
  21. 15 Sep, 2009 1 commit
  23. 04 Sep, 2009 1 commit
  25. 16 Jun, 2009 1 commit
    • GeunSik Lim's avatar
      debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. · 156f5a78
      GeunSik Lim authored 
      Many developers use "/debug/" or "/debugfs/" or "/sys/kernel/debug/"
directory name to mount debugfs filesystem for ftrace according to
./Documentation/tracers/ftrace.txt file.

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

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



Fix inconsistency of directory name to mount debugfs filesystem.

* From Steven Rostedt
  - find_debugfs() and tracing_files() in this patch.

Signed-off-by: default avatarGeunSik Lim <geunsik.lim@samsung.com>
Acked-by     : Inaky Perez-Gonzalez <inaky@linux.intel.com>
Reviewed-by  : Steven Rostedt <rostedt@goodmis.org>
Reviewed-by  : James Smart <james.smart@emulex.com>
CC: Jiri Kosina <trivial@kernel.org>
CC: David Airlie <airlied@linux.ie>
CC: Peter Osterlund <petero2@telia.com>
CC: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
CC: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
CC: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      156f5a78
  27. 12 Jun, 2009 1 commit
  29. 10 Jun, 2009 1 commit
  31. 29 May, 2009 1 commit
  33. 09 Apr, 2009 1 commit
    • Li Zefan's avatar
      tracing: consolidate documents · 66bb7488
      Li Zefan authored 
      

Move kmemtrace.txt, tracepoints.txt, ftrace.txt and mmiotrace.txt to
the new trace/ directory.

I didnt find any references to those documents in both source
files and documents, so no extra work needs to be done.

Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Acked-by: default avatarPekka Paalanen <pq@iki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
LKML-Reference: <49DD6E2B.6090200@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      66bb7488
  35. 08 Mar, 2009 1 commit
  37. 05 Mar, 2009 1 commit
  39. 19 Feb, 2009 2 commits
  41. 20 Jan, 2009 1 commit
  43. 28 Nov, 2008 1 commit
    • walimis's avatar
      ftrace: improve documentation · c072c249
      walimis authored 
      

Impact: extend documentation with notice of using wild cards correctly

We know that we can use wild cards to set set_ftrace_filter, but there's
problem when using them naively such as:

   echo h* > /debug/tracing/set_ftrace_filter

If there are files named with "h" prefix in current directory,
echo "h*" will echo these filenames to set_ftrace_filter, not the
intended "h*".

For example:

  $ cat /debug/tracing/available_filter_functions |grep ^hr |wc -l
  23
  $ ls
  $ touch hraa hrdd
  $ ls
  hraa  hrdd
  $ echo hr* > /debug/tracing/set_ftrace_filter
  $ cat /debug/tracing/set_ftrace_filter

No output in /debug/tracing/set_ftrace_filter!

If we use '' to escape wild cards, it works:

  $ ls
  hraa  hrdd
  $ echo "hr*" > /debug/tracing/set_ftrace_filter
  $ cat /debug/tracing/set_ftrace_filter |wc -l
  23

This problem can lead to unexpected result if current directory has a
lot of files.

Signed-off-by: default avatarwalimis <walimisdev@gmail.com>
Acked-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      c072c249
  45. 26 Nov, 2008 1 commit
    • Steven Rostedt's avatar
      ftrace: add function tracing to single thread · df4fc315
      Steven Rostedt authored 
      

Impact: feature to function trace a single thread

This patch adds the ability to function trace a single thread.
The file:

  /debugfs/tracing/set_ftrace_pid

contains the pid to trace. Valid pids are any positive integer.
Writing any negative number to this file will disable the pid
tracing and the function tracer will go back to tracing all of
threads.

This feature works with both static and dynamic function tracing.

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      df4fc315
  47. 23 Nov, 2008 2 commits
    • Török Edwin's avatar
      tracing: identify which executable object the userspace address belongs to · b54d3de9
      Török Edwin authored 
      

Impact: modify+improve the userstacktrace tracing visualization feature

Store thread group leader id, and use it to lookup the address in the
process's map. We could have looked up the address on thread's map,
but the thread might not exist by the time we are called. The process
might not exist either, but if you are reading trace_pipe, that is
unlikely.

Example usage:

 mount -t debugfs nodev /sys/kernel/debug
 cd /sys/kernel/debug/tracing
 echo userstacktrace >iter_ctrl
 echo sym-userobj >iter_ctrl
 echo sched_switch >current_tracer
 echo 1 >tracing_enabled
 cat trace_pipe >/tmp/trace&
 .... run application ...
 echo 0 >tracing_enabled
 cat /tmp/trace

You'll see stack entries like:

   /lib/libpthread-2.7.so[+0xd370]

You can convert them to function/line using:

   addr2line -fie /lib/libpthread-2.7.so 0xd370

Or:

   addr2line -fie /usr/lib/debug/libpthread-2.7.so 0xd370

For non-PIC/PIE executables this won't work:

   a.out[+0x73b]

You need to run the following: addr2line -fie a.out 0x40073b
(where 0x400000 is the default load address of a.out)

Signed-off-by: default avatarTörök Edwin <edwintorok@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      b54d3de9
    • Török Edwin's avatar
      tracing: add support for userspace stacktraces in tracing/iter_ctrl · 02b67518
      Török Edwin authored 
      

Impact: add new (default-off) tracing visualization feature

Usage example:

 mount -t debugfs nodev /sys/kernel/debug
 cd /sys/kernel/debug/tracing
 echo userstacktrace >iter_ctrl
 echo sched_switch >current_tracer
 echo 1 >tracing_enabled
 .... run application ...
 echo 0 >tracing_enabled

Then read one of 'trace','latency_trace','trace_pipe'.

To get the best output you can compile your userspace programs with
frame pointers (at least glibc + the app you are tracing).

Signed-off-by: default avatarTörök Edwin <edwintorok@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      02b67518
  49. 13 Nov, 2008 3 commits
    • Steven Rostedt's avatar
      ftrace: rename iter_ctrl to trace_options · ee6bce52
      Steven Rostedt authored 
      

Impact: rename file /debug/tracing/iter_ctrl to /debug/tracing/trace_options

The original ftrace had a file called "iter_ctrl" that would control
the way the output was iterated. But this file grew into a catch all
for different trace options. This patch renames the file from iter_ctrl
to trace_options to reflect this change.

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      ee6bce52
    • Steven Rostedt's avatar
      ftrace: show buffer size in kilobytes · 1696b2b0
      Steven Rostedt authored 
      

Impact: change the units of buffer_size_kb to kilobytes

This patch changes the units of the buffer_size_kb file to kilobytes.
Reading and writing to the file uses kilobytes as units. To help
users to know what units are used, the output of the file now
looks like:

  # cat /debug/tracing/buffer_size_kb
  1408

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      1696b2b0
    • Steven Rostedt's avatar
      ftrace: rename trace_entries to buffer_size_kb · a94c80e7
      Steven Rostedt authored 
      

Impact: rename of debugfs file trace_entries to buffer_size_kb

The original ftrace had fixed size entries, and the number of entries
was shown and modified via the file called trace_entries. By converting
to the unified trace buffer, we now allow for variable size entries
which makes the meaning of trace_entries pointless.

Since trace_size might be confused to the size of the trace, this patch
names it "buffer_size_kb" (thanks to Arjan van de Ven for this idea).

[ mingo@elte.hu: changed from buffer_size to buffer_size_kb ]

( Note, the units are still bytes - the next patch changes that,
  to keep the wide rename patch separate from the unit-change patch. )

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      a94c80e7
  51. 04 Nov, 2008 2 commits
  53. 30 Oct, 2008 1 commit
    • Steven Rostedt's avatar
      ftrace: handle archs that do not support irqs_disabled_flags · 9244489a
      Steven Rostedt authored 
      

Impact: build fix on non-lockdep architectures

Some architectures do not support a way to read the irq flags that
is set from "local_irq_save(flags)" to determine if interrupts were
disabled or enabled. Ftrace uses this information to display to the user
if the trace occurred with interrupts enabled or disabled.

Besides the fact that those archs that do not support this will fail to
compile, unless they fix it, we do not want to have the trace simply
say interrupts were not disabled or they were enabled, without knowing
the real answer.

This patch adds a 'X' in the output to let the user know that the
architecture they are running on does not support a way for the tracer
to determine if interrupts were enabled or disabled. It also lets those
same archs compile with tracing enabled.

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      9244489a
  55. 01 Aug, 2008 1 commit
  57. 16 Jul, 2008 1 commit
  59. 14 Jul, 2008 1 commit
  61. 10 Jul, 2008 1 commit

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