libperf: evlist: Fix --cpu argument on hybrid platform

Since the linked fixes: commit, specifying a CPU on hybrid platforms
results in an error because Perf tries to open an extended type event
on "

libperf: evlist: Fix --cpu argument on hybrid platform

Since the linked fixes: commit, specifying a CPU on hybrid platforms
results in an error because Perf tries to open an extended type event
on "any" CPU which isn't valid. Extended type events can only be opened
on CPUs that match the type.

Before (working):

$ perf record --cpu 1 -- true
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 2.385 MB perf.data (7 samples) ]

After (not working):

$ perf record -C 1 -- true
WARNING: A requested CPU in '1' is not supported by PMU 'cpu_atom' (CPUs 16-27) for event 'cycles:P'
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cpu_atom/cycles:P/).
/bin/dmesg | grep -i perf may provide additional information.

(Ignore the warning message, that's expected and not particularly
relevant to this issue).

This is because perf_cpu_map__intersect() of the user specified CPU (1)
and one of the PMU's CPUs (16-27) correctly results in an empty (NULL)
CPU map. However for the purposes of opening an event, libperf converts
empty CPU maps into an any CPU (-1) which the kernel rejects.

Fix it by deleting evsels with empty CPU maps in the specific case where
user requested CPU maps are evaluated.

Fixes: 251aa040244a ("perf parse-events: Wildcard most "numeric" events")
Reviewed-by: Ian Rogers <[email protected]>
Tested-by: Thomas Falcon <[email protected]>
Signed-off-by: James Clark <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>

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libperf cpumap: Refactor perf_cpu_map__merge()

The perf_cpu_map__merge() function has two arguments, 'orig' and
'other'. The function definition might cause confusion as it could give
the impressio

libperf cpumap: Refactor perf_cpu_map__merge()

The perf_cpu_map__merge() function has two arguments, 'orig' and
'other'. The function definition might cause confusion as it could give
the impression that the CPU maps in the two arguments are copied into a
new allocated structure, which is then returned as the result.

The purpose of the function is to merge the CPU map 'other' into the CPU
map 'orig'. This commit changes the 'orig' argument to a pointer to
pointer, so the new result will be updated into 'orig'.

The return value is changed to an int type, as an error number or 0 for
success.

Update callers and tests for the new function definition.

Reviewed-by: Adrian Hunter <[email protected]>
Signed-off-by: Leo Yan <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf evlist: Avoid out-of-bounds access

Parallel testing appears to show a race between allocating and setting
evsel ids. As there is a bounds check on the xyarray it yields a segv
like:

```
Add

libperf evlist: Avoid out-of-bounds access

Parallel testing appears to show a race between allocating and setting
evsel ids. As there is a bounds check on the xyarray it yields a segv
like:

```
AddressSanitizer:DEADLYSIGNAL

=================================================================

==484408==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000010

==484408==The signal is caused by a WRITE memory access.

==484408==Hint: address points to the zero page.

#0 0x55cef5d4eff4 in perf_evlist__id_hash tools/lib/perf/evlist.c:256
#1 0x55cef5d4f132 in perf_evlist__id_add tools/lib/perf/evlist.c:274
#2 0x55cef5d4f545 in perf_evlist__id_add_fd tools/lib/perf/evlist.c:315
#3 0x55cef5a1923f in store_evsel_ids util/evsel.c:3130
#4 0x55cef5a19400 in evsel__store_ids util/evsel.c:3147
#5 0x55cef5888204 in __run_perf_stat tools/perf/builtin-stat.c:832
#6 0x55cef5888c06 in run_perf_stat tools/perf/builtin-stat.c:960
#7 0x55cef58932db in cmd_stat tools/perf/builtin-stat.c:2878
...
```

Avoid this crash by early exiting the perf_evlist__id_add_fd and
perf_evlist__id_add is the access is out-of-bounds.

Signed-off-by: Ian Rogers <[email protected]>
Cc: Yang Jihong <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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

Passing NULL to perf_cpu_map__new() performs
perf_cpu_map__new_online_cpus(), just directly call
perf_cp

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

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 <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Andrew Jones <[email protected]>
Cc: André Almeida <[email protected]>
Cc: Athira Jajeev <[email protected]>
Cc: Atish Patra <[email protected]>
Cc: Changbin Du <[email protected]>
Cc: Darren Hart <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Garry <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Paran Lee <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Steinar H. Gunderson <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yang Jihong <[email protected]>
Cc: Yang Li <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf cpumap: Rename perf_cpu_map__empty() to perf_cpu_map__has_any_cpu_or_is_empty()

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

libperf cpumap: Rename perf_cpu_map__empty() to perf_cpu_map__has_any_cpu_or_is_empty()

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 <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexandre Ghiti <[email protected]>
Cc: Andrew Jones <[email protected]>
Cc: André Almeida <[email protected]>
Cc: Athira Jajeev <[email protected]>
Cc: Atish Patra <[email protected]>
Cc: Changbin Du <[email protected]>
Cc: Darren Hart <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Garry <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Paran Lee <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Steinar H. Gunderson <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yang Jihong <[email protected]>
Cc: Yang Li <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf evlist: Add perf_evlist__go_system_wide() helper

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 CPU

perf evlist: Add perf_evlist__go_system_wide() helper

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 <[email protected]>
Acked-by: Adrian Hunter <[email protected]>
Tested-by: Ravi Bangoria <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Anshuman Khandual <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Richter <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...

perf evlist: Propagate user CPU maps intersecting core PMU maps

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 b

perf evlist: Propagate user CPU maps intersecting core PMU maps

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 <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ali Saidi <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Dmitrii Dolgov <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jing Zhang <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Garry <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kang Minchul <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Madhavan Srinivasan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Ming Wang <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Thomas Richter <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Xing Zhengjun <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf evlist: Remove nr_groups

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

perf evlist: Remove nr_groups

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

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libperf evlist: Avoid a use of evsel idx

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.

Sign

libperf evlist: Avoid a use of evsel idx

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

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libperf: Propagate maps only if necessary

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

libperf: Propagate maps only if necessary

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 <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf: Populate system-wide evsel maps

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 activ

libperf: Populate system-wide evsel maps

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 <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...

perf tools: Add debug messages and comments for testing

Add debug messages to enable scripts to track aspects of 'perf record'
behaviour. The messages will be consumed after 'perf record' has run,
w

perf tools: Add debug messages and comments for testing

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 <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...

libperf evlist: Fix polling of system-wide events

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

libperf evlist: Fix polling of system-wide events

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 <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

show more ...

libperf evlist: Fix per-thread mmaps for multi-threaded targets

The offending commit removed mmap_per_thread(), which did not consider
the different set-output rules for per-thread mmaps i.e. in the

libperf evlist: Fix per-thread mmaps for multi-threaded targets

The offending commit removed mmap_per_thread(), which did not consider
the different set-output rules for per-thread mmaps i.e. in the per-thread
case set-output is used for file descriptors of the same thread not the
same cpu.

This was not immediately noticed because it only happens with
multi-threaded targets and we do not have a test for that yet.

Reinstate mmap_per_thread() expanding it to cover also system-wide per-cpu
events i.e. to continue to allow the mixing of per-thread and per-cpu
mmaps.

Debug messages (with -vv) show the file descriptors that are opened with
sys_perf_event_open. New debug messages are added (needs -vvv) that show
also which file descriptors are mmapped and which are redirected with
set-output.

In the per-cpu case (cpu != -1) file descriptors for the same CPU are
set-output to the first file descriptor for that CPU.

In the per-thread case (cpu == -1) file descriptors for the same thread are
set-output to the first file descriptor for that thread.

Example (process 17489 has 2 threads):

Before (but with new debug prints):

$ perf record --no-bpf-event -vvv --per-thread -p 17489
<SNIP>
sys_perf_event_open: pid 17489 cpu -1 group_fd -1 flags 0x8 = 5
sys_perf_event_open: pid 17490 cpu -1 group_fd -1 flags 0x8 = 6
<SNIP>
libperf: idx 0: mmapping fd 5
libperf: idx 0: set output fd 6 -> 5
failed to mmap with 22 (Invalid argument)

After:

$ perf record --no-bpf-event -vvv --per-thread -p 17489
<SNIP>
sys_perf_event_open: pid 17489 cpu -1 group_fd -1 flags 0x8 = 5
sys_perf_event_open: pid 17490 cpu -1 group_fd -1 flags 0x8 = 6
<SNIP>
libperf: mmap_per_thread: nr cpu values (may include -1) 1 nr threads 2
libperf: idx 0: mmapping fd 5
libperf: idx 1: mmapping fd 6
<SNIP>
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.018 MB perf.data (15 samples) ]

Per-cpu example (process 20341 has 2 threads, same as above):

$ perf record --no-bpf-event -vvv -p 20341
<SNIP>
sys_perf_event_open: pid 20341 cpu 0 group_fd -1 flags 0x8 = 5
sys_perf_event_open: pid 20342 cpu 0 group_fd -1 flags 0x8 = 6
sys_perf_event_open: pid 20341 cpu 1 group_fd -1 flags 0x8 = 7
sys_perf_event_open: pid 20342 cpu 1 group_fd -1 flags 0x8 = 8
sys_perf_event_open: pid 20341 cpu 2 group_fd -1 flags 0x8 = 9
sys_perf_event_open: pid 20342 cpu 2 group_fd -1 flags 0x8 = 10
sys_perf_event_open: pid 20341 cpu 3 group_fd -1 flags 0x8 = 11
sys_perf_event_open: pid 20342 cpu 3 group_fd -1 flags 0x8 = 12
sys_perf_event_open: pid 20341 cpu 4 group_fd -1 flags 0x8 = 13
sys_perf_event_open: pid 20342 cpu 4 group_fd -1 flags 0x8 = 14
sys_perf_event_open: pid 20341 cpu 5 group_fd -1 flags 0x8 = 15
sys_perf_event_open: pid 20342 cpu 5 group_fd -1 flags 0x8 = 16
sys_perf_event_open: pid 20341 cpu 6 group_fd -1 flags 0x8 = 17
sys_perf_event_open: pid 20342 cpu 6 group_fd -1 flags 0x8 = 18
sys_perf_event_open: pid 20341 cpu 7 group_fd -1 flags 0x8 = 19
sys_perf_event_open: pid 20342 cpu 7 group_fd -1 flags 0x8 = 20
<SNIP>
libperf: mmap_per_cpu: nr cpu values 8 nr threads 2
libperf: idx 0: mmapping fd 5
libperf: idx 0: set output fd 6 -> 5
libperf: idx 1: mmapping fd 7
libperf: idx 1: set output fd 8 -> 7
libperf: idx 2: mmapping fd 9
libperf: idx 2: set output fd 10 -> 9
libperf: idx 3: mmapping fd 11
libperf: idx 3: set output fd 12 -> 11
libperf: idx 4: mmapping fd 13
libperf: idx 4: set output fd 14 -> 13
libperf: idx 5: mmapping fd 15
libperf: idx 5: set output fd 16 -> 15
libperf: idx 6: mmapping fd 17
libperf: idx 6: set output fd 18 -> 17
libperf: idx 7: mmapping fd 19
libperf: idx 7: set output fd 20 -> 19
<SNIP>
[ perf record: Woken up 7 times to write data ]
[ perf record: Captured and wrote 0.020 MB perf.data (17 samples) ]

Fixes: ae4f8ae16a078964 ("libperf evlist: Allow mixing per-thread and per-cpu mmaps")
Reported-by: Tomáš Trnka <[email protected]>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216441
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf tools: Allow system-wide events to keep their own threads

System-wide events do not have threads, so do not propagate threads to
them.

Signed-off-by: Adrian Hunter <[email protected]>
Ac

perf tools: Allow system-wide events to keep their own threads

System-wide events do not have threads, so do not propagate threads to
them.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf tools: Allow system-wide events to keep their own CPUs

Currently, user_requested_cpus supplants system-wide CPUs when the evlist
has_user_cpus. Change that so that system-wide events retain the

perf tools: Allow system-wide events to keep their own CPUs

Currently, user_requested_cpus supplants system-wide CPUs when the evlist
has_user_cpus. Change that so that system-wide events retain their own
CPUs and they are added to all_cpus.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf stat: Add requires_cpu flag for uncore

Uncore events require a CPU i.e. it cannot be -1.

The evsel system_wide flag is intended for events that should be on every
CPU, which does not make sens

perf stat: Add requires_cpu flag for uncore

Uncore events require a CPU i.e. it cannot be -1.

The evsel system_wide flag is intended for events that should be on every
CPU, which does not make sense for uncore events because uncore events do
not map one-to-one with CPUs.

These 2 requirements are not exactly the same, so introduce a new flag
'requires_cpu' for the uncore case.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf evlist: Check nr_mmaps is correct

Print an error message if the predetermined number of mmaps is
incorrect.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <irog

libperf evlist: Check nr_mmaps is correct

Print an error message if the predetermined number of mmaps is
incorrect.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf evlist: Allow mixing per-thread and per-cpu mmaps

mmap_per_evsel() will skip events that do not match the CPU, so all CPUs
can be iterated in any case.

Signed-off-by: Adrian Hunter <adrian.

libperf evlist: Allow mixing per-thread and per-cpu mmaps

mmap_per_evsel() will skip events that do not match the CPU, so all CPUs
can be iterated in any case.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf tools: Allow all_cpus to be a superset of user_requested_cpus

To support collection of system-wide events with user requested CPUs,
all_cpus must be a superset of user_requested_cpus.

In order

perf tools: Allow all_cpus to be a superset of user_requested_cpus

To support collection of system-wide events with user requested CPUs,
all_cpus must be a superset of user_requested_cpus.

In order to support all_cpus to be a superset of user_requested_cpus,
all_cpus must be used instead of user_requested_cpus when dealing with CPUs
of all events instead of CPUs of requested events.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf evlist: Add evsel as a parameter to ->idx()

Add evsel as a parameter to ->idx() in preparation for correctly
determining whether an auxtrace mmap is needed.

Signed-off-by: Adrian Hunter <ad

libperf evlist: Add evsel as a parameter to ->idx()

Add evsel as a parameter to ->idx() in preparation for correctly
determining whether an auxtrace mmap is needed.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf evlist: Move ->idx() into mmap_per_evsel()

Move ->idx() into mmap_per_evsel() in preparation for adding evsel as a
parameter.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by

libperf evlist: Move ->idx() into mmap_per_evsel()

Move ->idx() into mmap_per_evsel() in preparation for adding evsel as a
parameter.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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libperf evlist: Remove ->idx() per_cpu parameter

Remove ->idx() per_cpu parameter because it isn't needed.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <irogers@googl

libperf evlist: Remove ->idx() per_cpu parameter

Remove ->idx() per_cpu parameter because it isn't needed.

Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf evlist: Clear all_cpus before propagating

all_cpus is merged into during propagation. Initially all_cpus is set
from PMU sysfs. perf_evlist__set_maps() will recompute it and change
evsel->cpus

perf evlist: Clear all_cpus before propagating

all_cpus is merged into during propagation. Initially all_cpus is set
from PMU sysfs. perf_evlist__set_maps() will recompute it and change
evsel->cpus to user_requested_cpus if they are given.

If all_cpus isn't cleared then the union of the user_requested_cpus and
PMU sysfs values is set to all_cpus, whereas just user_requested_cpus is
necessary.

To avoid this make all_cpus empty prior to propagation.

Reviewed-by: Adrian Hunter <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Cc: Alexander Antonov <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: German Gomez <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Fastabend <[email protected]>
Cc: John Garry <[email protected]>
Cc: KP Singh <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: Mathieu Poirier <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yonghong Song <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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perf tools: Fix segfault accessing sample_id xyarray

perf_evsel::sample_id is an xyarray which can cause a segfault when
accessed beyond its size. e.g.

# perf record -e intel_pt// -C 1 sleep 1

perf tools: Fix segfault accessing sample_id xyarray

perf_evsel::sample_id is an xyarray which can cause a segfault when
accessed beyond its size. e.g.

# perf record -e intel_pt// -C 1 sleep 1
Segmentation fault (core dumped)
#

That is happening because a dummy event is opened to capture text poke
events accross all CPUs, however the mmap logic is allocating according
to the number of user_requested_cpus.

In general, perf sometimes uses the evsel cpus to open events, and
sometimes the evlist user_requested_cpus. However, it is not necessary
to determine which case is which because the opened event file
descriptors are also in an xyarray, the size of whch can be used
to correctly allocate the size of the sample_id xyarray, because there
is one ID per file descriptor.

Note, in the affected code path, perf_evsel fd array is subsequently
used to get the file descriptor for the mmap, so it makes sense for the
xyarrays to be the same size there.

Fixes: d1a177595b3a824c ("libperf: Adopt perf_evlist__mmap()/munmap() from tools/perf")
Fixes: 246eba8e9041c477 ("perf tools: Add support for PERF_RECORD_TEXT_POKE")
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected] # 5.5+
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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