linux.git/tools/lib/perf/evlist.c, branch v6.8

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__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

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

perf evlist: Propagate user CPU maps intersecting core PMU maps

2023-05-27T12:38:39+00:00

The CPU map for a non-core PMU gives a default CPU value for
perf_event_open. For core PMUs the CPU map lists all CPUs the evsel
may be opened on. If there are >1 core PMU, the CPU maps will list the
CPUs for that core PMU, but the user_requested_cpus may contain CPUs
that are invalid for the PMU and cause perf_event_open to fail. To
avoid this, when propagating the CPU map for core PMUs intersect it
with the CPU map of the PMU (the evsel's "own_cpus").

Add comments to __perf_evlist__propagate_maps to explain its somewhat
complex behavior. Fix the related comments for system_wide in struct
perf_evsel.

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/20230527072210.2900565-9-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove nr_groups

2023-03-13T20:42:27+00:00

Maintaining the number of groups during event parsing is problematic
and since changing to sort/regroup events can only be computed by a
linear pass over the evlist. As the value is generally only used in
tests, rather than hold it in a variable compute it by passing over
the evlist when necessary.

This change highlights that libpfm's counting of groups with a single
entry disagreed with regular event parsing. The libpfm tests are
updated accordingly.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Florian Fischer 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Kim Phillips 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Stephane Eranian 
Cc: Suzuki Poulouse 
Cc: Xing Zhengjun 
Link: https://lore.kernel.org/r/20230312021543.3060328-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf evlist: Avoid a use of evsel idx

2023-03-13T18:11:34+00:00

Setting the leader iterates the list, so rather than use idx (which
may be changed through list reordering) just count the elements and
set afterwards.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Florian Fischer 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Kim Phillips 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Stephane Eranian 
Cc: Suzuki Poulouse 
Cc: Xing Zhengjun 
Link: https://lore.kernel.org/r/20230312021543.3060328-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Propagate maps only if necessary

2022-10-06T11:03:53+00:00

The current code propagate evsel's cpu map settings to evlist when it's
added to an evlist.  But the evlist->all_cpus and each evsel's cpus will
be updated in perf_evlist__set_maps() later.  No need to do it before
evlist's cpus are set actually.

In fact it discards this intermediate all_cpus maps at the beginning
of perf_evlist__set_maps().  Let's not do this.  It's only needed when
an evsel is added after the evlist cpu/thread maps are set.

Reviewed-by: Adrian Hunter 
Signed-off-by: Namhyung Kim 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20221003204647.1481128-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Populate system-wide evsel maps

2022-10-06T11:03:53+00:00

Setting proper cpu and thread maps for system wide evsels regardless of
user requested cpu in __perf_evlist__propagate_maps().  Those evsels
need to be active on all cpus always.  Do it in the libperf so that we
can guarantee it has proper maps.

Reviewed-by: Adrian Hunter 
Signed-off-by: Namhyung Kim 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20221003204647.1481128-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add debug messages and comments for testing

2022-10-04T11:55:23+00:00

Add debug messages to enable scripts to track aspects of 'perf record'
behaviour. The messages will be consumed after 'perf record' has run,
with the exception of "perf record has started" which is consequently
flushed.

Put comments so developers know which messages are also being used by test
scripts.

Signed-off-by: Adrian Hunter 
Acked-by: Namhyung Kim 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Link: https://lore.kernel.org/r/20220912083412.7058-11-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf evlist: Fix polling of system-wide events

2022-09-21T19:08:00+00:00

Originally, (refer commit f90d194a867a5a1d ("perf evlist: Do not poll
events that use the system_wide flag") there wasn't much reason to poll
system-wide events because:

 1. The mmaps get "merged" via set-output anyway (the per-cpu case)
 2. perf reads all mmaps when any event is woken
 3. system-wide mmaps do not fill up as fast as the mmaps for user
    selected events

But there was 1 reason not to poll which was that it prevented correct
termination due to POLLHUP on all user selected events.  That issue is
now easily resolved by using fdarray_flag__nonfilterable.

With the advent of commit ae4f8ae16a078964 ("libperf evlist: Allow
mixing per-thread and per-cpu mmaps"), system-wide mmaps can be used
also in the per-thread case where reason 1 does not apply.

Fix the omission of system-wide events from polling by using the
fdarray_flag__nonfilterable flag.

Example:

 Before:

    $ perf record --no-bpf-event -vvv -e intel_pt// --per-thread uname 2>err.txt
    Linux
    $ grep 'sys_perf_event_open.*=\|pollfd' err.txt
    sys_perf_event_open: pid 155076  cpu -1  group_fd -1  flags 0x8 = 5
    sys_perf_event_open: pid 155076  cpu -1  group_fd -1  flags 0x8 = 6
    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
    sys_perf_event_open: pid -1  cpu 1  group_fd -1  flags 0x8 = 9
    sys_perf_event_open: pid -1  cpu 2  group_fd -1  flags 0x8 = 10
    sys_perf_event_open: pid -1  cpu 3  group_fd -1  flags 0x8 = 11
    sys_perf_event_open: pid -1  cpu 4  group_fd -1  flags 0x8 = 12
    sys_perf_event_open: pid -1  cpu 5  group_fd -1  flags 0x8 = 13
    sys_perf_event_open: pid -1  cpu 6  group_fd -1  flags 0x8 = 14
    sys_perf_event_open: pid -1  cpu 7  group_fd -1  flags 0x8 = 15
    thread_data[0x55fb43c29e80]: pollfd[0] <- event_fd=5
    thread_data[0x55fb43c29e80]: pollfd[1] <- event_fd=6
    thread_data[0x55fb43c29e80]: pollfd[2] <- non_perf_event fd=4

 After:

    $ perf record --no-bpf-event -vvv -e intel_pt// --per-thread uname 2>err.txt
    Linux
    $ grep 'sys_perf_event_open.*=\|pollfd' err.txt
    sys_perf_event_open: pid 156316  cpu -1  group_fd -1  flags 0x8 = 5
    sys_perf_event_open: pid 156316  cpu -1  group_fd -1  flags 0x8 = 6
    sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 7
    sys_perf_event_open: pid -1  cpu 1  group_fd -1  flags 0x8 = 9
    sys_perf_event_open: pid -1  cpu 2  group_fd -1  flags 0x8 = 10
    sys_perf_event_open: pid -1  cpu 3  group_fd -1  flags 0x8 = 11
    sys_perf_event_open: pid -1  cpu 4  group_fd -1  flags 0x8 = 12
    sys_perf_event_open: pid -1  cpu 5  group_fd -1  flags 0x8 = 13
    sys_perf_event_open: pid -1  cpu 6  group_fd -1  flags 0x8 = 14
    sys_perf_event_open: pid -1  cpu 7  group_fd -1  flags 0x8 = 15
    thread_data[0x55cc19e58e80]: pollfd[0] <- event_fd=5
    thread_data[0x55cc19e58e80]: pollfd[1] <- event_fd=6
    thread_data[0x55cc19e58e80]: pollfd[2] <- event_fd=7
    thread_data[0x55cc19e58e80]: pollfd[3] <- event_fd=9
    thread_data[0x55cc19e58e80]: pollfd[4] <- event_fd=10
    thread_data[0x55cc19e58e80]: pollfd[5] <- event_fd=11
    thread_data[0x55cc19e58e80]: pollfd[6] <- event_fd=12
    thread_data[0x55cc19e58e80]: pollfd[7] <- event_fd=13
    thread_data[0x55cc19e58e80]: pollfd[8] <- event_fd=14
    thread_data[0x55cc19e58e80]: pollfd[9] <- event_fd=15
    thread_data[0x55cc19e58e80]: pollfd[10] <- non_perf_event fd=4

Fixes: ae4f8ae16a078964 ("libperf evlist: Allow mixing per-thread and per-cpu mmaps")
Signed-off-by: Adrian Hunter 
Acked-by: Namhyung Kim 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220915122612.81738-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo