linux.git/tools/perf, branch v5.6-rc7

tools: Fix off-by 1 relative directory includes

2020-03-06T11:36:46+00:00

This is currently working due to extra include paths in the build.

Committer testing:

  $ cd tools/include/uapi/asm/

Before this patch:

  $ ls -la ../../arch/x86/include/uapi/asm/errno.h
  ls: cannot access '../../arch/x86/include/uapi/asm/errno.h': No such file or directory
  $

After this patch;

  $ ls -la ../../../arch/x86/include/uapi/asm/errno.h
  -rw-rw-r--. 1 acme acme 31 Feb 20 12:42 ../../../arch/x86/include/uapi/asm/errno.h
  $

Check that that is still under tools/, i.e. hasn't escaped into the main
kernel sources:

  $ cd ../../../arch/x86/include/uapi/asm/
  $ pwd
  /home/acme/git/perf/tools/arch/x86/include/uapi/asm
  $

Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Acked-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexios Zavras 
Cc: Andi Kleen 
Cc: Greg Kroah-Hartman 
Cc: Igor Lubashev 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Mathieu Poirier 
Cc: Namhyung Kim 
Cc: Nick Desaulniers 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Cc: Wei Li 
Link: http://lore.kernel.org/lkml/20200306071110.130202-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf jevents: Fix leak of mapfile memory

2020-03-06T11:30:47+00:00

The memory for global pointer is never freed during normal program
execution, so let's do that in the main function exit as a good
programming practice.

A stray blank line is also removed.

Reported-by: Jiri Olsa 
Signed-off-by: John Garry 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: James Clark 
Cc: Joakim Zhang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: linuxarm@huawei.com
Link: http://lore.kernel.org/lkml/1583406486-154841-2-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf bench: Clear struct sigaction before sigaction() syscall

2020-03-06T11:30:47+00:00

Avoid garbage in sigaction structs used in sigaction() syscalls.
Valgrind is complaining about it.

Signed-off-by: Tommi Rantala 
Cc: Alexander Shishkin 
Cc: Changbin Du 
Cc: Darren Hart 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lore.kernel.org/lkml/20200305083714.9381-4-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo

perf bench futex-wake: Restore thread count default to online CPU count

2020-03-06T11:30:47+00:00

Since commit 3b2323c2c1c4 ("perf bench futex: Use cpumaps") the default
number of threads the benchmark uses got changed from number of online
CPUs to zero:

  $ perf bench futex wake
  # Running 'futex/wake' benchmark:
  Run summary [PID 15930]: blocking on 0 threads (at [private] futex 0x558b8ee4bfac), waking up 1 at a time.
  [Run 1]: Wokeup 0 of 0 threads in 0.0000 ms
  [...]
  [Run 10]: Wokeup 0 of 0 threads in 0.0000 ms
  Wokeup 0 of 0 threads in 0.0004 ms (+-40.82%)

Restore the old behavior by grabbing the number of online CPUs via
cpu->nr:

  $ perf bench futex wake
  # Running 'futex/wake' benchmark:
  Run summary [PID 18356]: blocking on 8 threads (at [private] futex 0xb3e62c), waking up 1 at a time.
  [Run 1]: Wokeup 8 of 8 threads in 0.0260 ms
  [...]
  [Run 10]: Wokeup 8 of 8 threads in 0.0270 ms
  Wokeup 8 of 8 threads in 0.0419 ms (+-24.35%)

Fixes: 3b2323c2c1c4 ("perf bench futex: Use cpumaps")
Signed-off-by: Tommi Rantala 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Darren Hart 
Cc: Davidlohr Bueso 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lore.kernel.org/lkml/20200305083714.9381-3-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo

perf top: Fix stdio interface input handling with glibc 2.28+

2020-03-06T11:30:47+00:00

Since glibc 2.28 when running 'perf top --stdio', input handling no
longer works, but hitting any key always just prints the "Mapped keys"
help text.

To fix it, call clearerr() in the display_thread() loop to clear any EOF
sticky errors, as instructed in the glibc NEWS file
(https://sourceware.org/git/?p=glibc.git;a=blob;f=NEWS):

 * All stdio functions now treat end-of-file as a sticky condition.  If you
   read from a file until EOF, and then the file is enlarged by another
   process, you must call clearerr or another function with the same effect
   (e.g. fseek, rewind) before you can read the additional data.  This
   corrects a longstanding C99 conformance bug.  It is most likely to affect
   programs that use stdio to read interactive input from a terminal.
   (Bug #1190.)

Signed-off-by: Tommi Rantala 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20200305083714.9381-2-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Fix undefined string comparision spotted by clang's -Wstring-compare

2020-03-06T11:30:29+00:00

clang warns:

  util/block-info.c:298:18: error: result of comparison against a string
  literal is unspecified (use an explicit string comparison function
  instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                          ^  ~~~~~~~~~~~~~~~
  util/block-info.c:298:51: error: result of comparison against a string
  literal is unspecified (use an explicit string comparison function
  instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                                                           ^  ~~~~~~~~~~~~~~~
  util/block-info.c:298:18: error: result of comparison against a string
  literal is unspecified (use an explicit string
  comparison function instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                          ^  ~~~~~~~~~~~~~~~
  util/block-info.c:298:51: error: result of comparison against a string
  literal is unspecified (use an explicit string comparison function
  instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                                                           ^  ~~~~~~~~~~~~~~~
  util/map.c:434:15: error: result of comparison against a string literal
  is unspecified (use an explicit string comparison function instead)
  [-Werror,-Wstring-compare]
                  if (srcline != SRCLINE_UNKNOWN)
                              ^  ~~~~~~~~~~~~~~~

Reviewer Notes:

Looks good to me. Some more context:
https://clang.llvm.org/docs/DiagnosticsReference.html#wstring-compare
The spec says:
J.1 Unspecified behavior
The following are unspecified:
.. Whether two string literals result in distinct arrays (6.4.5).

Signed-off-by: Nick Desaulniers 
Reviewed-by: Ian Rogers 
Cc: Alexander Shishkin 
Cc: Changbin Du 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: John Keeping 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: clang-built-linux@googlegroups.com
Link: https://github.com/ClangBuiltLinux/linux/issues/900
Link: http://lore.kernel.org/lkml/20200223193456.25291-1-nick.desaulniers@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Don't try to find a vmlinux file when looking for kernel modules

2020-03-03T19:20:01+00:00

The dso->kernel value is now set to everything that is in
machine->kmaps, but that was being used to decide if vmlinux lookup is
needed, which ended up making that lookup be made for kernel modules,
that now have dso->kernel set, leading to these kinds of warnings when
running on a machine with compressed kernel modules, like fedora:31:

  [root@five ~]# perf record -F 10000 -a sleep 2
  [ perf record: Woken up 1 times to write data ]
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  [ perf record: Captured and wrote 1.024 MB perf.data (1366 samples) ]
  [root@five ~]#

This happens when collecting the buildid, when we find samples for
kernel modules, fix it by checking if the looked up DSO is a kernel
module by other means.

Fixes: 02213cec64bb ("perf maps: Mark module DSOs with kernel type")
Tested-by: Jiri Olsa 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Kim Phillips 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Ravi Bangoria 
Link: http://lore.kernel.org/lkml/20200302191007.GD10335@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf bench: Share some global variables to fix build with gcc 10

2020-03-03T19:19:49+00:00

Noticed with gcc 10 (fedora rawhide) that those variables were not being
declared as static, so end up with:

  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  make[4]: *** [/git/perf/tools/build/Makefile.build:145: /tmp/build/perf/bench/perf-in.o] Error 1

Prefix those with bench__ and add them to bench/bench.h, so that we can
share those on the tools needing to access those variables from signal
handlers.

Acked-by: Thomas Gleixner 
Cc: Adrian Hunter 
Cc: Davidlohr Bueso 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/20200303155811.GD13702@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf parse-events: Use asprintf() instead of strncpy() to read tracepoint files

2020-03-02T14:55:47+00:00

Make the code more compact by using asprintf() instead of malloc()+strncpy() which also uses
less memory and avoids these warnings with gcc 10:

    CC       /tmp/build/perf/util/cloexec.o
  In file included from /usr/include/string.h:495,
                   from util/parse-events.h:12,
                   from util/parse-events.c:18:
  In function ‘strncpy’,
      inlined from ‘tracepoint_id_to_path’ at util/parse-events.c:271:5:
  /usr/include/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ offset [275, 511] from the object at ‘sys_dirent’ is out of the bounds of referenced subobject ‘d_name’ with type ‘char[256]’ at offset 19 [-Werror=array-bounds]
    106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In file included from /usr/include/dirent.h:61,
                   from util/parse-events.c:5:
  util/parse-events.c: In function ‘tracepoint_id_to_path’:
  /usr/include/bits/dirent.h:33:10: note: subobject ‘d_name’ declared here
     33 |     char d_name[256];  /* We must not include limits.h! */
        |          ^~~~~~
  In file included from /usr/include/string.h:495,
                   from util/parse-events.h:12,
                   from util/parse-events.c:18:
  In function ‘strncpy’,
      inlined from ‘tracepoint_id_to_path’ at util/parse-events.c:273:5:
  /usr/include/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ offset [275, 511] from the object at ‘evt_dirent’ is out of the bounds of referenced subobject ‘d_name’ with type ‘char[256]’ at offset 19 [-Werror=array-bounds]
    106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In file included from /usr/include/dirent.h:61,
                   from util/parse-events.c:5:
  util/parse-events.c: In function ‘tracepoint_id_to_path’:
  /usr/include/bits/dirent.h:33:10: note: subobject ‘d_name’ declared here
     33 |     char d_name[256];  /* We must not include limits.h! */
        |          ^~~~~~
    CC       /tmp/build/perf/util/call-path.o

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/20200302145535.GA28183@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Do not return pointers to local variables

2020-03-02T14:23:03+00:00

It is possible to return a pointer to a local variable when looking up
the architecture name for the running system and no normalization is
done on that value, i.e. we may end up returning the uts.machine local
variable.

While this doesn't happen on most arches, as normalization takes place,
lets fix this by making that a static variable and optimize it a bit by
not always running uname(), only the first time.

Noticed in fedora rawhide running with:

  [perfbuilder@a5ff49d6e6e4 ~]$ gcc --version
  gcc (GCC) 10.0.1 20200216 (Red Hat 10.0.1-0.8)

Reported-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo