linux.git/tools/perf/util, branch v5.10

perf probe: Change function definition check due to broken DWARF

2020-11-27T17:36:15+00:00

Since some gcc generates a broken DWARF which lacks DW_AT_declaration
attribute from the subprogram DIE of function prototype.
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97060)

So, in addition to the DW_AT_declaration check, we also check the
subprogram DIE has DW_AT_inline or actual entry pc.

Committer testing:

  # cat /etc/fedora-release
  Fedora release 33 (Thirty Three)
  #

Before:

  # perf test vfs_getname
  78: Use vfs_getname probe to get syscall args filenames             : FAILED!
  79: Check open filename arg using perf trace + vfs_getname          : FAILED!
  81: Add vfs_getname probe to get syscall args filenames             : FAILED!
  #

After:

  # perf test vfs_getname
  78: Use vfs_getname probe to get syscall args filenames             : Ok
  79: Check open filename arg using perf trace + vfs_getname          : Ok
  81: Add vfs_getname probe to get syscall args filenames             : Ok
  #

Reported-by: Thomas Richter 
Signed-off-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Sumanth Korikkar 
Link: http://lore.kernel.org/lkml/160645613571.2824037.7441351537890235895.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Fix to die_entrypc() returns error correctly

2020-11-27T17:33:17+00:00

Fix die_entrypc() to return error correctly if the DIE has no
DW_AT_ranges attribute. Since dwarf_ranges() will treat the case as an
empty ranges and return 0, we have to check it by ourselves.

Fixes: 91e2f539eeda ("perf probe: Fix to show function entry line as probe-able")
Signed-off-by: Masami Hiramatsu 
Cc: Sumanth Korikkar 
Cc: Thomas Richter 
Link: http://lore.kernel.org/lkml/160645612634.2824037.5284932731175079426.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Use proper cpu for shadow stats

2020-11-27T17:31:37+00:00

Currently perf stat shows some metrics (like IPC) for defined events.
But when no aggregation mode is used (-A option), it shows incorrect
values since it used a value from a different cpu.

Before:

  $ perf stat -aA -e cycles,instructions sleep 1

   Performance counter stats for 'system wide':

  CPU0      116,057,380      cycles
  CPU1       86,084,722      cycles
  CPU2       99,423,125      cycles
  CPU3       98,272,994      cycles
  CPU0       53,369,217      instructions      #    0.46  insn per cycle
  CPU1       33,378,058      instructions      #    0.29  insn per cycle
  CPU2       58,150,086      instructions      #    0.50  insn per cycle
  CPU3       40,029,703      instructions      #    0.34  insn per cycle

       1.001816971 seconds time elapsed

So the IPC for CPU1 should be 0.38 (= 33,378,058 / 86,084,722)
but it was 0.29 (= 33,378,058 / 116,057,380) and so on.

After:

  $ perf stat -aA -e cycles,instructions sleep 1

   Performance counter stats for 'system wide':

  CPU0      109,621,384      cycles
  CPU1      159,026,454      cycles
  CPU2       99,460,366      cycles
  CPU3      124,144,142      cycles
  CPU0       44,396,706      instructions      #    0.41  insn per cycle
  CPU1      120,195,425      instructions      #    0.76  insn per cycle
  CPU2       44,763,978      instructions      #    0.45  insn per cycle
  CPU3       69,049,079      instructions      #    0.56  insn per cycle

       1.001910444 seconds time elapsed

Fixes: 44d49a600259 ("perf stat: Support metrics in --per-core/socket mode")
Reported-by: Sam Xi 
Signed-off-by: Namhyung Kim 
Reviewed-by: Andi Kleen 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lore.kernel.org/lkml/20201127041404.390276-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Synthesize cgroup events only if needed

2020-11-27T17:26:33+00:00

It didn't check the tool->cgroup_events bit which is set when the
--all-cgroups option is given.  Without it, samples will not have cgroup
info so no reason to synthesize.

We can check the PERF_RECORD_CGROUP records after running perf record
*WITHOUT* the --all-cgroups option:

Before:

  $ perf report -D | grep CGROUP
  0 0 0x8430 [0x38]: PERF_RECORD_CGROUP cgroup: 1 /
          CGROUP events:          1
          CGROUP events:          0
          CGROUP events:          0

After:

  $ perf report -D | grep CGROUP
          CGROUP events:          0
          CGROUP events:          0
          CGROUP events:          0

Committer testing:

Before:

  # perf record -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 2.208 MB perf.data (10003 samples) ]
  # perf report -D | grep "CGROUP events"
            CGROUP events:        146
            CGROUP events:          0
            CGROUP events:          0
  #

After:

  # perf record -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 2.208 MB perf.data (10448 samples) ]
  # perf report -D | grep "CGROUP events"
            CGROUP events:          0
            CGROUP events:          0
            CGROUP events:          0
  #

With all-cgroups:

  # perf record --all-cgroups -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 2.374 MB perf.data (11526 samples) ]
  # perf report -D | grep "CGROUP events"
            CGROUP events:        146
            CGROUP events:          0
            CGROUP events:          0
  #

Fixes: 8fb4b67939e16 ("perf record: Add --all-cgroups option")
Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lore.kernel.org/lkml/20201127054356.405481-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Update copy of libbpf's hashmap.c

2020-11-27T17:19:33+00:00

To pick the changes in:

  7a078d2d18801bba ("libbpf, hashmap: Fix undefined behavior in hash_bits")

That don't entail any changes in tools/perf.

This addresses this perf build warning:

  Warning: Kernel ABI header at 'tools/perf/util/hashmap.h' differs from latest version at 'tools/lib/bpf/hashmap.h'
  diff -u tools/perf/util/hashmap.h tools/lib/bpf/hashmap.h

Not a kernel ABI, its just that this uses the mechanism in place for
checking kernel ABI files drift.

Cc: Adrian Hunter 
Cc: Daniel Borkmann 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'

2020-11-12T20:55:41+00:00

To bring in the change made in this cset:

  4d6ffa27b8e5116c ("x86/lib: Change .weak to SYM_FUNC_START_WEAK for arch/x86/lib/mem*_64.S")
  6dcc5627f6aec4cb ("x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_*")

I needed to define SYM_FUNC_START_LOCAL() as SYM_L_GLOBAL as
mem{cpy,set}_{orig,erms} are used by 'perf bench'.

This silences these perf tools build warnings:

  Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
  diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
  Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S'
  diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: Fangrui Song 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Jiri Slaby 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add missing swap for cgroup events

2020-11-03T12:16:41+00:00

It was missed to add a swap function for PERF_RECORD_CGROUP.

Fixes: ba78c1c5461c ("perf tools: Basic support for CGROUP event")
Signed-off-by: Namhyung Kim 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lore.kernel.org/lkml/20201102140228.303657-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add missing swap for ino_generation

2020-11-03T12:15:02+00:00

We are missing swap for ino_generation field.

Fixes: 5c5e854bc760 ("perf tools: Add attr->mmap2 support")
Signed-off-by: Jiri Olsa 
Acked-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20201101233103.3537427-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Initialize output buffer in build_id__sprintf

2020-11-03T12:14:45+00:00

We display garbage for undefined build_id objects, because we don't
initialize the output buffer.

Signed-off-by: Jiri Olsa 
Acked-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20201101233103.3537427-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf scripting python: Avoid declaring function pointers with a visibility attribute

2020-11-03T11:32:43+00:00

To avoid this:

  util/scripting-engines/trace-event-python.c: In function 'python_start_script':
  util/scripting-engines/trace-event-python.c:1595:2: error: 'visibility' attribute ignored [-Werror=attributes]
   1595 |  PyMODINIT_FUNC (*initfunc)(void);
        |  ^~~~~~~~~~~~~~

That started breaking when building with PYTHON=python3 and these gcc
versions (I haven't checked with the clang ones, maybe it breaks there
as well):

  # export PERF_TARBALL=http://192.168.86.5/perf/perf-5.9.0.tar.xz
  # dm  fedora:33 fedora:rawhide
     1   107.80 fedora:33         : Ok   gcc (GCC) 10.2.1 20201005 (Red Hat 10.2.1-5), clang version 11.0.0 (Fedora 11.0.0-1.fc33)
     2    92.47 fedora:rawhide    : Ok   gcc (GCC) 10.2.1 20201016 (Red Hat 10.2.1-6), clang version 11.0.0 (Fedora 11.0.0-1.fc34)
  #

Avoid that by ditching that 'initfunc' function pointer with its:

    #define Py_EXPORTED_SYMBOL _attribute_ ((visibility ("default")))
    #define PyMODINIT_FUNC Py_EXPORTED_SYMBOL PyObject*

And just call PyImport_AppendInittab() at the end of the ifdef python3
block with the functions that were being attributed to that initfunc.

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