• James Clark's avatar
    perf evlist: Fix evlist__new_default() for > 1 core PMU · 7814fe24
    James Clark authored
    The 'Session topology' test currently fails with this message when
    evlist__new_default() opens more than one event:
    
      32: Session topology                                                :
      --- start ---
      templ file: /tmp/perf-test-vv5YzZ
      Using CPUID 0x00000000410fd070
      Opening: unknown-hardware:HG
      ------------------------------------------------------------
      perf_event_attr:
        type                             0 (PERF_TYPE_HARDWARE)
        config                           0xb00000000
        disabled                         1
      ------------------------------------------------------------
      sys_perf_event_open: pid 0  cpu -1  group_fd -1  flags 0x8 = 4
      Opening: unknown-hardware:HG
      ------------------------------------------------------------
      perf_event_attr:
        type                             0 (PERF_TYPE_HARDWARE)
        config                           0xa00000000
        disabled                         1
      ------------------------------------------------------------
      sys_perf_event_open: pid 0  cpu -1  group_fd -1  flags 0x8 = 5
      non matching sample_type
      FAILED tests/topology.c:73 can't get session
      ---- end ----
      Session topology: FAILED!
    
    This is because when re-opening the file and parsing the header, Perf
    expects that any file that has more than one event has the sample ID
    flag set. Perf record already sets the flag in a similar way when there
    is more than one event, so add the same logic to evlist__new_default().
    
    evlist__new_default() is only currently used in tests, so I don't
    expect this change to have any other side effects. The other tests that
    use it don't save and re-open the file so don't hit this issue.
    
    The session topology test has been failing on Arm big.LITTLE platforms
    since commit 251aa040 ("perf parse-events: Wildcard most
    "numeric" events") when evlist__new_default() started opening multiple
    events for 'cycles'.
    
    Fixes: 251aa040 ("perf parse-events: Wildcard most "numeric" events")
    Reviewed-by: default avatarIan Rogers <irogers@google.com>
    Signed-off-by: default avatarJames Clark <james.clark@arm.com>
    [ This was failing as well on a Rocket Lake Refresh/14700k Intel hybrid system - Arnaldo ]
    Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    Tested-by: default avatarIan Rogers <irogers@google.com>
    Tested-by: default avatarKan Liang <kan.liang@linux.intel.com>
    Cc: Adrian Hunter <adrian.hunter@intel.com>
    Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
    Cc: Changbin Du <changbin.du@huawei.com>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Jiri Olsa <jolsa@kernel.org>
    Cc: Mark Rutland <mark.rutland@arm.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Yang Jihong <yangjihong1@huawei.com>
    Closes: https://lore.kernel.org/lkml/CAP-5=fWVQ-7ijjK3-w1q+k2WYVNHbAcejb-xY0ptbjRw476VKA@mail.gmail.com/
    Link: https://lore.kernel.org/r/20240124094358.489372-1-james.clark@arm.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    7814fe24
evlist.c 58.5 KB