linux.git/tools/perf/util/evlist.c, branch v6.9

perf evlist: Fix evlist__new_default() for > 1 core PMU

2024-01-30T14:40:28+00:00

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 251aa040244a3b17 ("perf parse-events: Wildcard most
"numeric" events") when evlist__new_default() started opening multiple
events for 'cycles'.

Fixes: 251aa040244a3b17 ("perf parse-events: Wildcard most "numeric" events")
Reviewed-by: Ian Rogers 
Signed-off-by: James Clark 
[ This was failing as well on a Rocket Lake Refresh/14700k Intel hybrid system - Arnaldo ]
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Ian Rogers 
Tested-by: Kan Liang 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Changbin Du 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Yang Jihong 
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.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Move event attributes to after the / when uniquefying using the PMU name

2023-12-19T00:23:28+00:00

When turning an event with attributes to the format including the PMU we
need to move the "event:attributes" format to "event/attributes/" so
that we can copy the event displayed and use it in the command line,
i.e. in 'perf top' we had:

 1K cpu_atom/cycles:P/
 11K cpu_core/cycles:P/

If I try to use that on the command line:

  # perf top -e cpu_atom/cycles:P/
  event syntax error: 'cpu_atom/cycles:P/'
                                \___ Bad event or PMU

  Unable to find PMU or event on a PMU of 'cpu_atom'

  Initial error:
  event syntax error: 'cpu_atom/cycles:P/'
                                \___ unknown term 'cycles:P' for pmu
  'cpu_atom'

  valid terms:

    event,pc,edge,offcore_rsp,ldlat,inv,umask,cmask,config,config1,config2,config3,name,period,freq,branch_type,time,call-graph,stack-size,no-inherit,inherit,max-stack,nr,no-overwrite,overwrite ,driver-config,percore,aux-output,aux-sample-size,metric-id,raw,legacy-cache,hardware
  Run
    'perf list' for a list of valid events

  Usage: perf top []

     -e, --event    event selector. use 'perf list' to list available events
  #

Tested-by: Kan Liang 
Cc: Hector Martin 
Cc: Ian Rogers 
Cc: Marc Zyngier 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/lkml/ZXxyanyZgWBTOnoK@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf top: Uniform the event name for the hybrid machine

2023-12-14T22:13:10+00:00

It's hard to distinguish the default cycles events among hybrid PMUs.
For example,

  $ perf top
  Available samples
  385 cycles:P
  903 cycles:P

The other tool, e.g., perf record, uniforms the event name and adds the
hybrid PMU name before opening the event. So the events can be easily
distinguished. Apply the same methodology for the perf top as well.

The evlist__uniquify_name() will be invoked by both record and top.
Move it to util/evlist.c

With the patch:

  $ perf top
  Available samples
  148 cpu_atom/cycles:P/
  1K cpu_core/cycles:P/

Reviewed-by: Ian Rogers 
Signed-off-by: Kan Liang 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Hector Martin 
Cc: Marc Zyngier 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/r/20231214144612.1092028-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf cpumap: Replace usage of perf_cpu_map__new(NULL) with perf_cpu_map__new_online_cpus()

2023-12-12T17:55:13+00:00

Passing NULL to perf_cpu_map__new() performs
perf_cpu_map__new_online_cpus(), just directly call
perf_cpu_map__new_online_cpus() to be more intention revealing.

Reviewed-by: James Clark 
Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexandre Ghiti 
Cc: Andrew Jones 
Cc: André Almeida 
Cc: Athira Jajeev 
Cc: Atish Patra 
Cc: Changbin Du 
Cc: Darren Hart 
Cc: Davidlohr Bueso 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Nick Desaulniers 
Cc: Paolo Bonzini 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Yang Li 
Cc: Yanteng Si 
Cc: bpf@vger.kernel.org
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20231129060211.1890454-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf cpumap: Rename perf_cpu_map__dummy_new() to perf_cpu_map__new_any_cpu()

2023-12-12T17:01:47+00:00

Rename perf_cpu_map__dummy_new() to perf_cpu_map__new_any_cpu() to
better indicate this is creating a CPU map for the perf_event_open "any"
CPU case.

Reviewed-by: James Clark 
Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexandre Ghiti 
Cc: Andrew Jones 
Cc: André Almeida 
Cc: Athira Jajeev 
Cc: Atish Patra 
Cc: Changbin Du 
Cc: Darren Hart 
Cc: Davidlohr Bueso 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Nick Desaulniers 
Cc: Paolo Bonzini 
Cc: Paran Lee 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Yang Li 
Cc: Yanteng Si 
Cc: bpf@vger.kernel.org
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20231129060211.1890454-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Avoid frequency mode for the dummy event

2023-09-27T04:43:20+00:00

Dummy events are created with an attribute where the period and freq
are zero. evsel__config will then see the uninitialized values and
initialize them in evsel__default_freq_period. As fequency mode is
used by default the dummy event would be set to use frequency
mode. However, this has no effect on the dummy event but does cause
unnecessary timers/interrupts. Avoid this overhead by setting the
period to 1 for dummy events.

evlist__add_aux_dummy calls evlist__add_dummy then sets freq=0 and
period=1. This isn't necessary after this change and so the setting is
removed.

From Stephane:

The dummy event is not counting anything. It is used to collect mmap
records and avoid a race condition during the synthesize mmap phase of
perf record. As such, it should not cause any overhead during active
profiling. Yet, it did. Because of a bug the dummy event was
programmed as a sampling event in frequency mode. Events in that mode
incur more kernel overheads because on timer tick, the kernel has to
look at the number of samples for each event and potentially adjust
the sampling period to achieve the desired frequency. The dummy event
was therefore adding a frequency event to task and ctx contexts we may
otherwise not have any, e.g.,

  perf record -a -e cpu/event=0x3c,period=10000000/.

On each timer tick the perf_adjust_freq_unthr_context() is invoked and
if ctx->nr_freq is non-zero, then the kernel will loop over ALL the
events of the context looking for frequency mode ones. In doing, so it
locks the context, and enable/disable the PMU of each hw event. If all
the events of the context are in period mode, the kernel will have to
traverse the list for nothing incurring overhead. The overhead is
multiplied by a very large factor when this happens in a guest kernel.
There is no need for the dummy event to be in frequency mode, it does
not count anything and therefore should not cause extra overhead for
no reason.

Fixes: 5bae0250237f ("perf evlist: Introduce perf_evlist__new_dummy constructor")
Reported-by: Stephane Eranian 
Signed-off-by: Ian Rogers 
Acked-by: Adrian Hunter 
Cc: Yang Jihong 
Cc: Kan Liang 
Link: https://lore.kernel.org/r/20230916035640.1074422-1-irogers@google.com
Signed-off-by: Namhyung Kim

perf evlist: Add evlist__findnew_tracking_event() helper

2023-09-12T20:31:32+00:00

Currently, intel-bts, intel-pt, and arm-spe may add tracking event to the
evlist. We may need to search for the tracking event for some settings.

Therefore, add evlist__findnew_tracking_event() helper.

If system_wide is true, evlist__findnew_tracking_event() set the cpu map
of the evsel to all online CPUs.

Signed-off-by: Yang Jihong 
Acked-by: Adrian Hunter 
Tested-by: Ravi Bangoria 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Anshuman Khandual 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Thomas Richter 
Link: https://lore.kernel.org/r/20230904023340.12707-3-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Free stats in all evlist destruction

2023-06-12T18:57:53+00:00

There is no evsel free stats, freeing in the evlist__delete ensures
memory leaks are avoided. Issues detected with "perf stat report" and
leak sanitizer, perf stat uses perf_session__delete to free the
evlist. Add dummy symbol for python build.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Brian Robbins 
Cc: Changbin Du 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Ivan Babrou 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Miguel Ojeda 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Wenyu Liu 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Ye Xingchen 
Cc: Yuan Can 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230608232823.4027869-14-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Reduce scope of evlist__has_hybrid

2023-05-27T12:39:51+00:00

Function is only used in printout, reduce scope to
stat-display.c. Remove the now empty evlist-hybrid.c and
evlist-hybrid.h.

Reviewed-by: Kan Liang 
Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Athira Rajeev 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kang Minchul 
Cc: Leo Yan 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Ming Wang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Suzuki Poulouse 
Cc: Thomas Richter 
Cc: Will Deacon 
Cc: Xing Zhengjun 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230527072210.2900565-15-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove evlistadd_default

2023-05-27T12:39:37+00:00

__evlist__add_default adds a cycles event to a typically empty evlist
and was extended for hybrid with evlist__add_default_hybrid, as more
than 1 PMU was necessary. Rather than have dedicated logic for the
cycles event, this change switches to parsing 'cycles:P' which will
handle wildcarding the PMUs appropriately for hybrid.

Reviewed-by: Kan Liang 
Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Athira Rajeev 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kang Minchul 
Cc: Leo Yan 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Ming Wang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Suzuki Poulouse 
Cc: Thomas Richter 
Cc: Will Deacon 
Cc: Xing Zhengjun 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230527072210.2900565-14-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo