linux-stable.git/tools/perf/util/thread_map.c, branch linux-4.4.y

perf thread_map: Use readdir() instead of deprecated readdir_r()

2017-07-15T09:57:48+00:00

commit 3354cf71104de49326d19d2f9bdb1f66eea52ef4 upstream.

The readdir() function is thread safe as long as just one thread uses a
DIR, which is the case in thread_map, so, to avoid breaking the build
with glibc-2.23.90 (upcoming 2.24), use it instead of readdir_r().

See: http://man7.org/linux/man-pages/man3/readdir.3.html

"However, in modern implementations (including the glibc implementation),
concurrent calls to readdir() that specify different directory streams
are thread-safe.  In cases where multiple threads must read from the
same directory stream, using readdir() with external synchronization is
still preferable to the use of the deprecated readdir_r(3) function."

Noticed while building on a Fedora Rawhide docker container.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-del8h2a0f40z75j4r42l96l0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

perf thread_map: Correctly size buffer used with dirent->dt_name

2017-07-15T09:57:48+00:00

commit bdf23a9a190d7ecea092fd5c4aabb7d4bd0a9980 upstream.

The size of dirent->dt_name is NAME_MAX + 1, but the size for the 'path'
buffer is hard coded at 256, which may truncate it because we also
prepend "/proc/", so that all that into account and thank gcc 7 for this
warning:

  /git/linux/tools/perf/util/thread_map.c: In function 'thread_map__new_by_uid':
  /git/linux/tools/perf/util/thread_map.c:119:39: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size 250 [-Werror=format-truncation=]
     snprintf(path, sizeof(path), "/proc/%s", dirent->d_name);
                                         ^~
  In file included from /usr/include/stdio.h:939:0,
                   from /git/linux/tools/perf/util/thread_map.c:5:
  /usr/include/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 7 and 262 bytes into a destination of size 256
     return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          __bos (__s), __fmt, __va_arg_pack ());
          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-csy0r8zrvz5efccgd4k12c82@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

2015-07-21T05:58:06+00:00

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

New features:

  - Allow filtering out of perf's PID via 'perf record --exclude-perf'. (Wang Nan)

  - 'perf trace' now supports syscall groups, like strace, i.e:

      $ trace -e file touch file

    Will expand 'file' into multiple, file related, syscalls. More work needed to
    add extra groups for other syscall groups, and also to complement what was
    added for the 'file' group, included as a proof of concept. (Arnaldo Carvalho de Melo)

  - Add lock_pi stresser to 'perf bench futex', to test the kernel code
    related to FUTEX_(UN)LOCK_PI. (Davidlohr Bueso)

User visible fixes:

  - Apply --filter to all events in a glob matching, not just the last one. (Wang Nan)

Documentation changes:

  - Document setting '-e pmu/period=N/' in the 'perf record' man page. (Kan Liang)

Infrastructure changes:

  - 'perf probe' code simplifications and movements to separate files. (Masami Hiramatsu)

  - Fix makefile generation under 'dash'. (Sergei Trofimovich)

Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ingo Molnar

perf strlist: Make dupstr be the default and part of an extensible config parm

2015-07-20T15:13:34+00:00

So that we can pass more info to strlist__new() without having to change
its function signature, just adding entries to the strlist_config struct
with sensible defaults for when those fields are not specified.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-5uaaler4931i0s9sedxjquhq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf thread_map: Fix the sizeof() calculation for map entries

2015-07-09T15:28:53+00:00

When we started adding extra stuff per array entry, growing the size of
those entries to more than sizeof(pid_t), we had to convert those sizeof
operations to the more robust sizeof(map->map[0]) idiom, that is future
proof, i.e. if/when we add more stuff to those entries, that expression
will produce the new per-entry size.

And besides that, we need to zero out those extra fields, that sometimes
may not get filled, like when we couldn't care less about the comms,
since we don't need those, but since we will try freeing it at
thread_map__delete(), we better fix it.

That is why a thread_map__realloc() was provided.

But that method wasn't used in thread_map__new_by_uid(), fix it.

Reported-by: Ingo Molnar 
Fixes: 792402fd5c0a ("perf thrad_map: Add comm string into array")
Fixes: 9d7e8c3a96e5 ("perf tools: Add thread_map__(alloc|realloc) helpers")
Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-6a0swlm6m8lnu3wpjv284hkb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf thrad_map: Add comm string into array

2015-06-26T14:07:01+00:00

Adding support to hold comm name together with pids in 'struct
thread_map'. It will be useful for --per-thread option to display task
pid together with task name.

Adding thread_map__read_comms function that reads/set
comm string for the 'struct thread_map'.

Getting the task name from /proc/$pid/comm.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1435310967-14570-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf thread_map: Introduce thread_map__reset function

2015-06-26T14:03:41+00:00

We need to reset newly allocated 'struct thread_map_data' entries,
because we will introduce new comm memeber, which will get set later or
not at all.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1435310967-14570-2-git-send-email-jolsa@kernel.org
[ Use sizeof(map->map[0]) to be independent of the array entry type ]
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add reference counting for thread_map object

2015-06-25T18:15:50+00:00

Adding reference counting for thread_map object, so it could be easily
shared among other objects.

Using thread_map__put instead thread_map__delete and making
thread_map__delete static.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1435012588-9007-5-git-send-email-jolsa@kernel.org
[ Adjustments to move it ahead of the "comm" patches ]
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Future-proof thread_map allocation size calculation

2015-06-25T18:15:49+00:00

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/20150625174840.GH3253@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf thread_map: Don't access the array entries directly

2015-06-23T21:21:44+00:00

Instead provide a method to set the array entries, and another to access
the contents.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1435012588-9007-2-git-send-email-jolsa@kernel.org
[ Split providing the set/get accessors from transforming the entries structs ]
Signed-off-by: Arnaldo Carvalho de Melo