linux-toradex.git/tools/lib/perf/include, branch v6.8-rc7

libperf cpumap: Document perf_cpu_map__nr()'s behavior

2023-12-19T00:34:46+00:00

perf_cpu_map__nr()'s behavior around an empty CPU map is strange as it
returns that there is 1 CPU. Changing code that may rely on this
behavior is hard, we can at least document the behavior.

Reviewed-by: James Clark 
Signed-off-by: Ian Rogers 
Acked-by: Adrian Hunter 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Alexandre Ghiti 
Cc: Andrew Jones 
Cc: André Almeida 
Cc: Athira Rajeev 
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: 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 
Link: https://lore.kernel.org/r/20231129060211.1890454-15-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf cpumap: Add for_each_cpu() that skips the "any CPU" case

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

When iterating CPUs in a CPU map it is often desirable to skip the "any
CPU" (aka dummy) case. Add a helper for this and use in builtin-record.

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/20231129060211.1890454-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf cpumap: Rename perf_cpu_map__empty() to perf_cpu_map__has_any_cpu_or_is_empty()

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

The name perf_cpu_map_empty is misleading as true is also returned
when the map contains an "any" CPU (aka dummy) map.

Rename to perf_cpu_map__has_any_cpu_or_is_empty(), later changes will
(re)introduce perf_cpu_map__empty() and perf_cpu_map__has_any_cpu().

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/20231129060211.1890454-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf cpumap: Rename perf_cpu_map__default_new() to perf_cpu_map__new_online_cpus() and prefer sysfs

2023-12-12T17:54:51+00:00

Rename perf_cpu_map__default_new() to perf_cpu_map__new_online_cpus() to
better indicate what the implementation does.

Read the online CPUs from /sys/devices/system/cpu/online first before
using sysconf() as it can't accurately configure holes in the CPU map.

If sysconf() is used, warn when the configured and online processors
disagree.

When reading from a file, if the read doesn't yield a CPU map then
return an empty map rather than the default online. This avoids
recursion but also better yields being able to detect failures.

Add more comments.

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/20231129060211.1890454-3-irogers@google.com
[ s/syfs/sysfs/g typo ]
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

libperf: Lazily allocate/size mmap event copy

2023-11-30T22:25:19+00:00

The event copy in the mmap is used to have storage to read an event. Not
all users of mmaps read the events, such as perf record. The amount of
buffer was also statically set to PERF_SAMPLE_MAX_SIZE rather than the
amount necessary from the header's event size.

Switch to a model where the event_copy is reallocated if too small to
the event's size. This adds the potential for the event to move, so if a
copy of the event pointer were stored it could be broken. All the
current users do:

  while(event = perf_mmap__read_event()) { ... }

and so they would be broken due to the event being overwritten if they
had stored the pointer. Manual inspection and address sanitizer testing
also shows the event pointer not being stored.

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Jajeev 
Cc: Changbin Du 
Cc: Colin Ian King 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: German Gomez 
Cc: Guilherme Amadio 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Li Dong 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Masami Hiramatsu (Google) 
Cc: Miguel Ojeda 
Cc: Ming Wang 
Cc: Nick Terrell 
Cc: Paolo Bonzini 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Vincent Whitchurch 
Cc: Wenyu Liu 
Cc: Yang Jihong 
Link: https://lore.kernel.org/r/20231127220902.1315692-3-irogers@google.com
[ Replace two lines with equivalent zfree(&map->event_copy) ]
Signed-off-by: Arnaldo Carvalho de Melo

libperf rc_check: Add RC_CHK_EQUAL

2023-10-25T20:37:22+00:00

Comparing pointers with reference count checking is tricky to avoid a
SEGV. Add a convenience macro to simplify and use.

Signed-off-by: Ian Rogers 
Cc: K Prateek Nayak 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Anshuman Khandual 
Cc: German Gomez 
Cc: James Clark 
Cc: Nick Terrell 
Cc: Sean Christopherson 
Cc: Changbin Du 
Cc: liuwenyu 
Cc: Yang Jihong 
Cc: Masami Hiramatsu 
Cc: Miguel Ojeda 
Cc: Song Liu 
Cc: Leo Yan 
Cc: Kajol Jain 
Cc: Andi Kleen 
Cc: Kan Liang 
Cc: Athira Rajeev 
Cc: Yanteng Si 
Cc: Liam Howlett 
Cc: Paolo Bonzini 
Link: https://lore.kernel.org/r/20231024222353.3024098-5-irogers@google.com
Signed-off-by: Namhyung Kim

libperf rc_check: Make implicit enabling work for GCC

2023-10-25T20:36:50+00:00

Make the implicit REFCOUNT_CHECKING robust to when building with GCC.

Fixes: 9be6ab181b7b ("libperf rc_check: Enable implicitly with sanitizers")
Signed-off-by: Ian Rogers 
Cc: K Prateek Nayak 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Anshuman Khandual 
Cc: German Gomez 
Cc: James Clark 
Cc: Nick Terrell 
Cc: Sean Christopherson 
Cc: Changbin Du 
Cc: liuwenyu 
Cc: Yang Jihong 
Cc: Masami Hiramatsu 
Cc: Miguel Ojeda 
Cc: Song Liu 
Cc: Leo Yan 
Cc: Kajol Jain 
Cc: Andi Kleen 
Cc: Kan Liang 
Cc: Athira Rajeev 
Cc: Yanteng Si 
Cc: Liam Howlett 
Cc: Paolo Bonzini 
Link: https://lore.kernel.org/r/20231024222353.3024098-4-irogers@google.com
Signed-off-by: Namhyung Kim

perf evlist: Add perf_evlist__go_system_wide() helper

2023-09-12T20:31:22+00:00

For dummy events that keep tracking, we may need to modify its cpu_maps.

For example, change the cpu_maps to record sideband events for all CPUS.

Add perf_evlist__go_system_wide() helper to support this scenario.

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/20230904023340.12707-2-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Get rid of attr.id field

2023-08-29T17:16:14+00:00

Now there's no in-tree user of the field.  To remove the possible bug
later, let's get rid of the 'id' field and add a comment for that.

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20230825152552.112913-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo