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  1. 20 6月, 2015 10 次提交
  3. 18 6月, 2015 7 次提交
    • A
      perf top: Allow disabling/enabling events dynamicly · 5d484f99
      由 Arnaldo Carvalho de Melo 提交于 
      Now it is possible to press CTRL+z at anytime and that will disable the
events being monitored, essentially turning 'top' into 'report', with
pressing CTRL+z again making it enable the events again, returning to
the 'top' behaviour, i.e. dynamic + decaying of older samples.

One may want, for instance, play with:

    -d, --delay <n>       number of seconds to delay between refreshes

and:

    -z, --zero            zero history across updates

Plus CTRL+z to see only the events since last zeroing, etc.
Suggested-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-zq7tnh5462blt2yda0bcxh5b@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      5d484f99
    • A
      perf evlist: Add toggle_enable() method · 2b56bcfb
      由 Arnaldo Carvalho de Melo 提交于 
      For an upcoming feature in 'perf top' we will have a hotkey to
enable/disable events, so remember if the events in the list are
enabled or disabled and allows toggling this state using a new
method.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-64c4jvdl5feg2zhimxvokqka@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      2b56bcfb
    • S
      perf trace: Fix race condition at the end of started workloads · 7951722d
      由 Sukadev Bhattiprolu 提交于 
      I get following crash on multiple systems and across several releases
(at least since v3.18).

	Core was generated by `/tmp/perf trace sleep 0.2 '.
	Program terminated with signal SIGSEGV, Segmentation fault.
	#0  perf_mmap__read_head (mm=0x3fff9bf30070) at util/evlist.h:195
	195		u64 head = ACCESS_ONCE(pc->data_head);
	(gdb) bt
	#0  perf_mmap__read_head (mm=0x3fff9bf30070) at util/evlist.h:195
	#1  perf_evlist__mmap_read (evlist=0x10027f11910, idx=<optimized out>)
	    at util/evlist.c:637
	#2  0x000000001003ce4c in trace__run (argv=<optimized out>,
	    argc=<optimized out>, trace=0x3fffd7b28288) at builtin-trace.c:2259
	#3  cmd_trace (argc=<optimized out>, argv=<optimized out>,
	    prefix=<optimized out>) at builtin-trace.c:2799
	#4  0x00000000100657b8 in run_builtin (p=0x10176798 <commands+480>, argc=3,
	    argv=0x3fffd7b2b550) at perf.c:370
	#5  0x00000000100063e8 in handle_internal_command (argv=0x3fffd7b2b550, argc=3)
	    at perf.c:429
	#6  run_argv (argv=0x3fffd7b2af70, argcp=0x3fffd7b2af7c) at perf.c:473
	#7  main (argc=3, argv=0x3fffd7b2b550) at perf.c:588

The problem seems to be a race condition, when the application has just
exited.  Some/all fds associated with the perf-events (tracepoints) go
into a POLLHUP/ POLLERR state and the mmap region associated with those
events are unmapped (in perf_evlist__filter_pollfd()).

But we go back and do a perf_evlist__mmap_read() which assumes that the
mmaps are still valid and we hit the crash.

If the mapping for an event is released, its refcnt is 0 (and ->base
is NULL), so ensure we have non-zero refcount before accessing the map.

Note that perf-record has a similar logic but unlike perf-trace, the
record__mmap_read_all() checks the evlist->mmap[i].base before accessing
the map.
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20150612060003.GA19913@us.ibm.com
[ Fixed it up to use atomic_read() ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      7951722d
    • M
      perf probe: Speed up perf probe --list by caching debuginfo · 7737af01
      由 Masami Hiramatsu 提交于 
      Speed up the "perf probe --list" by caching the last used debuginfo.
perf probe --list always open and load debuginfo for each entry of probe
list. This takes very a long time.

E.g. with vfs_* events (total 96 probes)

  [root@localhost perf]# time  ./perf probe -l &> /dev/null

  real    0m25.376s
  user    0m24.381s
  sys     0m1.012s

To solve this issue, this adds debuginfo_cache to cache the
last used debuginfo on memory.

With this fix, the perf-probe --list significantly improves
its speed.

  [root@localhost perf]#  time  ./perf probe -l &> /dev/null

  real    0m0.161s
  user    0m0.136s
  sys     0m0.025s
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150617145854.19715.15314.stgit@localhost.localdomainSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      7737af01
    • M
      perf probe: Show usage even if the last event is skipped · d350bd57
      由 Masami Hiramatsu 提交于 
      When the last part of converted events are blacklisted or out-of-text,
those are skipped and perf probe doesn't show usage examples.  This
fixes it to show the example even if the last part of event list is
skipped.

E.g. without this patch, events are added, but suddenly end:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
    probe:vfs_open       (on vfs_*)
  ...
    probe:vfs_dentry_acceptable (on vfs_*)
    probe:vfs_load_quota_inode (on vfs_*)
  #

With this fix:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
  ...
    probe:vfs_load_quota_inode (on vfs_*)

  You can now use it in all perf tools, such as:

	perf record -e probe:vfs_load_quota_inode -aR sleep 1

Note that this can be reproduced ONLY IF the vfs_caches_init* is the
last part of matched symbol list. I've checked this happens on
"3.19.0-generic #18-Ubuntu" kernel binary.
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150616115057.19906.5502.stgit@localhost.localdomainSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      d350bd57
    • W
      perf tools: Move libtraceevent dynamic list to separated LDFLAGS variable · 5d618324
      由 Wang Nan 提交于 
      Commit e3d09ec8 ("tools lib traceevent:
Export dynamic symbols used by traceevent plugins") adds libtraceevent
dynamic list directly into LDFLAGS, which makes all targets depend on
that list through LDFLAGS.

This is not good since some of targets like libgtk.so doesn't use plugin
at all, but require the existance of that list because of linker
options.

This patch isolates the -Xlink option into LIBTRACEEVENT_DYNAMIC_LIST_LDFLAGS,
makes only perf and perf.so use it.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1434552389-89144-1-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      5d618324
    • W
      perf tools: Fix a problem when opening old perf.data with different byte order · b30b6172
      由 Wang Nan 提交于 
      Following error occurs when trying to use 'perf report' on x86_64 to
cross analysis a perf.data generated by an old perf on a big-endian
machine:

 # perf report
 *** Error in `/home/w00229757/perf': free(): invalid next size (fast): 0x00000000032c99f0 ***
 ======= Backtrace: =========
 /lib64/libc.so.6(+0x6eeef)[0x7ff6ff7e2eef]
 /lib64/libc.so.6(+0x78cae)[0x7ff6ff7eccae]
 /lib64/libc.so.6(+0x79987)[0x7ff6ff7ed987]
 /path/to/perf[0x4ac734]
 /path/to/perf[0x4ac829]
 /path/to/perf(perf_header__process_sections+0x129)[0x4ad2c9]
 /path/to/perf(perf_session__read_header+0x2e1)[0x4ad9e1]
 /path/to/perf(perf_session__new+0x168)[0x4bd458]
 /path/to/perf(cmd_report+0xfa0)[0x43eb70]
 /path/to/perf[0x47adc3]
 /path/to/perf(main+0x5f6)[0x42fd06]
 /lib64/libc.so.6(__libc_start_main+0xf5)[0x7ff6ff795bd5]
 /path/to/perf[0x42fe35]
 ======= Memory map: ========
 [SNIP]

The bug is in perf_event__attr_swap(). It swaps all fields in 'struct
perf_event_attr' without checking whether the swapped field exist or
not. In addition, in read_event_desc() allocs memory for attr according
to size read from perf.data.

Therefore, if the perf.data is collected by an old perf (without
aux_watermark, for example), when perf_event__attr_swap() swaping
attr->aux_watermark it destroy malloc's metadata.

This patch introduces boundary checking in perf_event__attr_swap(). It
adds macros bswap_field_64 and bswap_field_32 into
perf_event__attr_swap() to make it only swap exist fields.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1434534999-85347-1-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b30b6172
  5. 17 6月, 2015 1 次提交
  7. 16 6月, 2015 9 次提交
  9. 13 6月, 2015 1 次提交
    • M
      perf probe: Cut off the gcc optimization postfixes from function name · 35a23ff9
      由 Masami Hiramatsu 提交于 
      Cut off the postfixes which gcc added for optimized routines from the
event name automatically generated from symbol name, since *probe-events
doesn't accept it.  Those symbols will be used if we don't use debuginfo
to find target functions.

E.g. without this fix;
  -----
  # perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf.isra.23 _text+4869328
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  -----
With this fix;
  -----
  perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf _text+4869328
    probe:alloc_buf      (on alloc_buf.isra.23)

  You can now use it in all perf tools, such as:

  	perf record -e probe:alloc_buf -aR sleep 1

  -----
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150612050820.20548.41625.stgit@localhost.localdomainSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      35a23ff9
  11. 12 6月, 2015 2 次提交
    • D
      perf tools: Update MANIFEST per files removed from kernel · c8ad7063
      由 David Ahern 提交于 
      Building perf out of kernel tree is currently broken because the
MANIFEST file refers to kernel files that have been removed. With this
patch make perf-targz-src-pkg succeeds as does building perf using the
generated tarfile.
Signed-off-by: NDavid Ahern <david.ahern@oracle.com>
Link: http://lkml.kernel.org/r/1433526173-172332-1-git-send-email-david.ahern@oracle.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      c8ad7063
    • A
      trace: Beautify perf_event_open syscall · a1c2552d
      由 Arnaldo Carvalho de Melo 提交于 
      Syswide tracing and then running 'stat' and 'trace':

 $ perf trace -e perf_event_open
 1034.649 (0.019 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = -1 EINVAL Invalid argument
 1034.670 (0.008 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1) = -1 EINVAL Invalid argument
 1034.681 (0.007 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1) = -1 EINVAL Invalid argument
 1034.692 (0.007 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1) = -1 EINVAL Invalid argument
 9986.983 (0.014 ms): trace/6139 perf_event_open(attr_uptr: 0x7ffd9c629320, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.026 (0.016 ms): trace/6139 perf_event_open(attr_uptr: 0x37c7e70, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.041 (0.008 ms): trace/6139 perf_event_open(attr_uptr: 0x37c7e70, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.489 (0.092 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.536 (0.044 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 4
 9987.580 (0.041 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 5
 9987.620 (0.037 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 7
 9987.659 (0.035 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, group_fd: -1, flags: FD_CLOEXEC) = 8
 9987.692 (0.031 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 9
 9987.727 (0.032 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 10
 9987.761 (0.031 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 11

Need to intercept perf_copy_attr() with a kprobe or with eBPF...

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-njb105hab2i3t5dexym9lskl@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a1c2552d
  13. 11 6月, 2015 3 次提交
  15. 10 6月, 2015 2 次提交
  17. 08 6月, 2015 5 次提交
    • A
      perf tools: Reference count struct dso · d3a7c489
      由 Arnaldo Carvalho de Melo 提交于 
      This has a different model than the 'thread' and 'map' struct lifetimes:
there is not a definitive "don't use this DSO anymore" event, i.e. we may
get many 'struct map' holding references to the '/usr/lib64/libc-2.20.so'
DSO but then at some point some DSO may have no references but we still
don't want to straight away release its resources, because "soon" we may
get a new 'struct map' that needs it and we want to reuse its symtab or
other resources.

So we need some way to garbage collect it when crossing some memory
usage threshold, which is left for anoter patch, for now it is
sufficient to release it when calling dsos__exit(), i.e. when deleting
the whole list as part of deleting the 'struct machine' containing it,
which will leave only referenced objects being used.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-majzgz07cm90t2tejrjy4clf@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      d3a7c489
    • A
      perf tools: Protect accesses the dso rbtrees/lists with a rw lock · e8807844
      由 Arnaldo Carvalho de Melo 提交于 
      To allow concurrent access, next step: refcount struct dso instances, so
that we can ditch unused them when the last map pointing to it goes
away.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-yk1k08etpd2aoe3tnrf0oizn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e8807844
    • A
      perf machine: Fix up some more method names · 9f2de315
      由 Arnaldo Carvalho de Melo 提交于 
      Calling the function 'machine__new_module' implies a new 'module' will
be allocated, when in fact what is returned is a 'struct map' instance,
that not necessarily will be instantiated, as if one already exists with
the given module name, it will be returned instead.

So be consistent with other "find and if not there, create" like
functions, like machine__findnew_thread, machine__findnew_dso, etc, and
rename it to machine__findnew_module_map(), that in turn will call
machine__findnew_module_dso().

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-acv830vd3hwww2ih5vjtbmu3@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      9f2de315
    • H
      perf record: Fix perf.data size in no-buildid mode · 457ae94a
      由 He Kuang 提交于 
      The size of perf.data is missing update in no-buildid mode, which gives
wrong output result.

Before this patch:

  $ perf.perf record -B -e syscalls:sys_enter_open uname
  Linux
  [ perf record: Woken up 1 times to  write data ]
  [ perf record: Captured and wrote 0.000 MB perf.data ]

After this patch:

  $ perf.perf record -B -e syscalls:sys_enter_open uname
  Linux
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.001 MB perf.data ]
Signed-off-by: NHe Kuang <hekuang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1432819050-30511-1-git-send-email-hekuang@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      457ae94a
    • H
      tools lib traceevent: Export dynamic symbols used by traceevent plugins · e3d09ec8
      由 He Kuang 提交于 
      Traceevent plugins need dynamic symbols exported from libtraceevent.a,
otherwise a dlopen error will occur during plugins loading.

This patch uses dynamic-list-file to export dynamic symbols which will
be used in plugins to perf executable.

The problem is covered up if feature-libpython is enabled, because
PYTHON_EMBED_LDOPTS contains '-Xlinker --export-dynamic' which adds all
symbols to the dynamic symbol table. So we should reproduce the problem
by setting NO_LIBPYTHON=1.

Before this patch:

  (Prepare plugins)
  $ ls /root/.traceevent/plugins/
  plugin_sched_switch.so
  plugin_function.so
  ...

  $ perf record -e 'ftrace:function' ls

  $ perf script
    Warning: could not load plugin '/mnt/data/root/.traceevent/plugins/plugin_sched_switch.so'
    /root/.traceevent/plugins/plugin_sched_switch.so: undefined symbol: pevent_unregister_event_handler

    Warning: could not load plugin '/root/.traceevent/plugins/plugin_function.so'
    /root/.traceevent/plugins/plugin_function.so: undefined symbol: warning
    ...
           :1049  1049 [000]  9666.754487: ftrace:function:  ffffffff8118bc50 <-- ffffffff8118c5b3
           :1049  1049 [000]  9666.754487: ftrace:function:  ffffffff818e2440 <-- ffffffff8118bc75
           :1049  1049 [000]  9666.754487: ftrace:function:  ffffffff8106eee0 <-- ffffffff811212e2

After this patch:

  $ perf record -e 'ftrace:function' ls
  $ perf script
           :1049  1049 [000]  9666.754487: ftrace:function: __set_task_comm
           :1049  1049 [000]  9666.754487: ftrace:function:    _raw_spin_lock
           :1049  1049 [000]  9666.754487: ftrace:function: task_tgid_nr_ns
           ...
Signed-off-by: NHe Kuang <hekuang@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1432819735-35040-1-git-send-email-hekuang@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e3d09ec8