linux-stable.git/tools/perf/util/thread.c, branch v4.12.2

perf tools: Include errno.h where needed

2017-04-19T16:01:51+00:00

Removing it from util.h, part of an effort to disentangle the includes
hell, that makes changes to util.h or something included by it to cause
a complete rebuild of the tools.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-ztrjy52q1rqcchuy3rubfgt2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add include where ARRAY_SIZE() is used

2017-04-19T16:01:44+00:00

To pave the way for further cleanups where linux/kernel.h may stop being
included in some header.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-qqxan6tfsl6qx3l0v3nwgjvk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add PERF_RECORD_NAMESPACES to include namespaces related info

2017-03-14T14:38:23+00:00

Introduce a new option to record PERF_RECORD_NAMESPACES events emitted
by the kernel when fork, clone, setns or unshare are invoked. And update
perf-record documentation with the new option to record namespace
events.

Committer notes:

Combined it with a later patch to allow printing it via 'perf report -D'
and be able to test the feature introduced in this patch. Had to move
here also perf_ns__name(), that was introduced in another later patch.

Also used PRIu64 and PRIx64 to fix the build in some enfironments wrt:

  util/event.c:1129:39: error: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'long long unsigned int' [-Werror=format=]
     ret  += fprintf(fp, "%u/%s: %lu/0x%lx%s", idx
                                         ^
Testing it:

  # perf record --namespaces -a
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 1.083 MB perf.data (423 samples) ]
  #
  # perf report -D
  
  3 2028902078892 0x115140 [0xa0]: PERF_RECORD_NAMESPACES 14783/14783 - nr_namespaces: 7
                [0/net: 3/0xf0000081, 1/uts: 3/0xeffffffe, 2/ipc: 3/0xefffffff, 3/pid: 3/0xeffffffc,
                 4/user: 3/0xeffffffd, 5/mnt: 3/0xf0000000, 6/cgroup: 3/0xeffffffb]

  0x1151e0 [0x30]: event: 9
  .
  . ... raw event: size 48 bytes
  .  0000:  09 00 00 00 02 00 30 00 c4 71 82 68 0c 7f 00 00  ......0..q.h....
  .  0010:  a9 39 00 00 a9 39 00 00 94 28 fe 63 d8 01 00 00  .9...9...(.c....
  .  0020:  03 00 00 00 00 00 00 00 ce c4 02 00 00 00 00 00  ................
  
        NAMESPACES events:          1
  
  #

Signed-off-by: Hari Bathini 
Acked-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Alexei Starovoitov 
Cc: Ananth N Mavinakayanahalli 
Cc: Aravinda Prasad 
Cc: Brendan Gregg 
Cc: Daniel Borkmann 
Cc: Eric Biederman 
Cc: Peter Zijlstra 
Cc: Sargun Dhillon 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/148891930386.25309.18412039920746995488.stgit@hbathini.in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf thread: convert thread.refcnt from atomic_t to refcount_t

2017-03-03T22:07:16+00:00

The refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.

Signed-off-by: Elena Reshetova 
Signed-off-by: David Windsor 
Signed-off-by: Hans Liljestrand 
Signed-off-by: Kees Kook 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Andrew Morton 
Cc: David Windsor 
Cc: Greg Kroah-Hartman 
Cc: Hans Liljestrand 
Cc: Jiri Olsa 
Cc: Kees Kook 
Cc: Mark Rutland 
Cc: Matija Glavinic Pecotic 
Cc: Peter Zijlstra 
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-9-git-send-email-elena.reshetova@intel.com
[ Did missing conversion in __machine__remove_thread() ]
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Experiment with cppcheck

2016-10-03T14:24:13+00:00

Experimenting a bit using cppcheck[1], a static checker brought to my
attention by Colin, reducing the scope of some variables, reducing the
line of source code lines in the process:

  $ cppcheck --enable=style tools/perf/util/thread.c
  Checking tools/perf/util/thread.c...
  [tools/perf/util/thread.c:17]: (style) The scope of the variable 'leader' can be reduced.
  [tools/perf/util/thread.c:133]: (style) The scope of the variable 'err' can be reduced.
  [tools/perf/util/thread.c:273]: (style) The scope of the variable 'err' can be reduced.

Will continue later, but these are already useful, keep them.

1: https://sourceforge.net/p/cppcheck/wiki/Home/

Cc: Adrian Hunter 
Cc: Colin Ian King 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-ixws7lbycihhpmq9cc949ti6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Call unwind__prepare_access for forked thread

2016-07-04T23:27:25+00:00

Currently we call unwind__prepare_access for map event.  In case we
report fork event the thread inherits its parent's maps and
unwind__prepare_access is never called for the thread.

This causes unwind__get_entries seeing uninitialized
unwind_libunwind_ops and thus returning no callchain.

Adding unwind__prepare_access calls for fork even processing.

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: He Kuang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1467634583-29147-5-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Add initialized arg into unwind__prepare_access

2016-07-04T23:27:12+00:00

Adding initialized arg into unwind__prepare_access to get feedback about
the initialization state.

It's not possible to get it from error code, because we return 0 even in
case we don't recognize dso, which is valid.

The 'initialized' value is used in following patch to speedup
unwind__prepare_access calls logic in fork path.

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: He Kuang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1467634583-29147-4-git-send-email-jolsa@kernel.org
[ Remove ; after static inline function signatures, fixes build break ]
Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Check the target platform before assigning unwind methods

2016-06-07T18:09:36+00:00

Currently, 'perf script' uses host unwind methods to parse perf.data
callchain info without taking the target architecture into account, i.e.
assuming the perf.data file was generated on the same machine where the
analysis is being performed. So we get wrong result without any warnings
when unwinding callchains of x86(32-bit) on x86(64-bit) machine.

This patch adds an extra step that checks the target platform before
assigning unwind methods. In later patches in this series, we can use
this info to assign the right unwind methods for supported platforms.

Committer note:

After fixing it to register the local unwinder for live mode tools
('perf trace', 'perf top'), i.e. tools that don't use a perf.data file,
it works as intended and passes the 'perf test unwind' test:

  # perf trace -e nanosleep --call dwarf usleep 1
     0.328 ( 0.058 ms): usleep/11115 nanosleep(rqtp: 0x7fff083fa480) = 0
                                       __nanosleep_nocancel+0x7 (/usr/lib64/libc-2.22.so)
                                       usleep+0x34 (/usr/lib64/libc-2.22.so)
                                       main+0x1eb (/usr/bin/usleep)
                                       __libc_start_main+0xf0 (/usr/lib64/libc-2.22.so)
                                       _start+0x29 (/usr/bin/usleep)
  # perf test 48
  48: Test dwarf unwind         : Ok
  #

Signed-off-by: He Kuang 
Acked-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Ekaterina Tumanova 
Cc: Josh Poimboeuf 
Cc: Kan Liang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Pekka Enberg 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Sukadev Bhattiprolu 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1464924803-22214-11-git-send-email-hekuang@huawei.com
[ Fixed exit path for 'live' mode tools, where we need to default to local unwinding ]
Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Move unwind__prepare_access from thread_new into thread__insert_map

2016-06-07T15:08:52+00:00

To determine the libunwind methods to use, we should get the
32bit/64bit information from maps of a thread. When a thread is newly
created, the information is not prepared. This patch moves
unwind__prepare_access() into thread__insert_map() so we can get the
information we need from maps. Meanwhile, let thread__insert_map()
return value and show messages on error.

Signed-off-by: He Kuang 
Acked-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Ekaterina Tumanova 
Cc: Josh Poimboeuf 
Cc: Kan Liang 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Pekka Enberg 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Sukadev Bhattiprolu 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1464924803-22214-5-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf thread: Adopt get_main_thread from db-export.c

2016-05-30T15:41:43+00:00

Move the get_main_thread function from db-export.c to thread.c so that
it can be used elsewhere.

Signed-off-by: Andi Kleen 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1464051145-19968-2-git-send-email-andi@firstfloor.org
[ Removed leftover bits from db-export.h ]
Signed-off-by: Arnaldo Carvalho de Melo