kernel/linux.git/tools/perf/builtin-stat.c, branch linux-7.1.y

perf tools: Use calloc() where applicable

2026-04-09T02:21:05+00:00

Instead of using zalloc(nr_entries * sizeof_entry) that is what calloc() does. In some places where linux/zalloc.h isn't needed, remove it, add when needed and was getting it indirectly. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf stat: Fix crash on arm64

2026-04-02T19:51:09+00:00

Perf stat is crashing on arm64 hosts with the following issue: # make -C tools/perf DEBUG=1 # perf stat sleep 1 perf: util/evsel.c:2034: get_group_fd: Assertion `!(!leader->core.fd)' failed. [1] 1220794 IOT instruction (core dumped) ./perf stat The sorting function introduced by commit a745c0831c15c ("perf stat: Sort default events/metrics") compares events based on their individual properties. This can cause events from different groups to be interleaved, resulting in group members appearing before their leaders in the sorted evlist. When the iterator opens events in list order, a group member may be processed before its leader has been opened. For example, CPU_CYCLES (idx=32) with leader STALL_SLOT_BACKEND (idx=37) could be sorted before its leader, causing the crash when CPU_CYCLES tries to get its group fd from the not-yet-opened leader. Fix this by comparing events based on their leader's attributes instead of their own attributes when the events are in different groups. This ensures all members of a group share the same sort key as their leader, keeping groups together and guaranteeing leaders are opened before their members. Fixes: a745c0831c15c ("perf stat: Sort default events/metrics") Reported-by: Denis Yaroshevskiy Tested-by: Dmitry Ilvokhin Tested-by: Ian Rogers Signed-off-by: Breno Leitao Signed-off-by: Namhyung Kim

libperf cpumap: Make index and nr types unsigned

2026-04-01T21:50:53+00:00

The index into the cpumap array and the number of entries within the array can never be negative, so let's make them unsigned. This is prompted by reports that gcc 13 with -O6 is giving a alloc-size-larger-than errors. The change makes the cpumap changes and then updates the declaration of index variables throughout perf and libperf to be unsigned. The two things are hard to separate as compiler warnings about mixing signed and unsigned types breaks the build. Reported-by: Chingbin Li Closes: https://lore.kernel.org/lkml/20260212025127.841090-1-liqb365@163.com/ Tested-by: Chingbin Li Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf tools: Add --pmu-filter option for filtering PMUs

2026-03-27T20:58:01+00:00

This patch adds a new --pmu-filter option to perf-stat command to allow filtering events on specific PMUs. This is useful when there are multiple PMUs with same type (e.g. hisi_sicl2_cpa0 and hisi_sicl0_cpa0). [root@localhost tmp]# perf stat -M cpa_p0_avg_bw Performance counter stats for 'system wide': 19,417,779,115 hisi_sicl0_cpa0/cpa_cycles/ # 0.00 cpa_p0_avg_bw 0 hisi_sicl0_cpa0/cpa_p0_wr_dat/ 0 hisi_sicl0_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl0_cpa0/cpa_p0_rd_dat_32b/ 19,417,751,103 hisi_sicl10_cpa0/cpa_cycles/ # 0.00 cpa_p0_avg_bw 0 hisi_sicl10_cpa0/cpa_p0_wr_dat/ 0 hisi_sicl10_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl10_cpa0/cpa_p0_rd_dat_32b/ 19,417,730,679 hisi_sicl2_cpa0/cpa_cycles/ # 0.31 cpa_p0_avg_bw 75,635,749 hisi_sicl2_cpa0/cpa_p0_wr_dat/ 18,520,640 hisi_sicl2_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl2_cpa0/cpa_p0_rd_dat_32b/ 19,417,674,227 hisi_sicl8_cpa0/cpa_cycles/ # 0.00 cpa_p0_avg_bw 0 hisi_sicl8_cpa0/cpa_p0_wr_dat/ 0 hisi_sicl8_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl8_cpa0/cpa_p0_rd_dat_32b/ 19.417734480 seconds time elapsed [root@localhost tmp]# perf stat --pmu-filter hisi_sicl2_cpa0 -M cpa_p0_avg_bw Performance counter stats for 'system wide': 6,234,093,559 cpa_cycles # 0.60 cpa_p0_avg_bw 50,548,465 cpa_p0_wr_dat 7,552,182 cpa_p0_rd_dat_64b 0 cpa_p0_rd_dat_32b 6.234139320 seconds time elapsed Signed-off-by: Qinxin Xia Reviewed-by: Ian Rogers Signed-off-by: Namhyung Kim

perf stat: Fix opt->value type for parse_cache_level

2026-03-26T22:03:47+00:00

Commit f5803651b4a4 ("perf stat: Choose the most disaggregate command line option") changed aggregation option handling for `perf stat` but not `perf stat report` leading to parse_cache_level being passed a struct in the `perf stat` case but erroneously an aggr_mode enum value for `perf stat report`. Change the `perf stat report` aggregation handling to use the same opt_aggr_mode as `perf stat`. Also, just pass the boolean for consistency with other boolean argument handling. Fixes: f5803651b4a4 ("perf stat: Choose the most disaggregate command line option") Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf stat: Add no-affinity flag

2026-02-10T12:35:28+00:00

Add flag that disables affinity behavior. Using sched_setaffinity() to place a perf thread on a CPU can avoid certain interprocessor interrupts but may introduce a delay due to the scheduling, particularly on loaded machines. Add a command line option to disable the behavior. This behavior is less present in other tools like `perf record`, as it uses a ring buffer and doesn't make repeated system calls. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Andres Freund Cc: Dapeng Mi Cc: Dr. David Alan Gilbert Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Thomas Richter Cc: Yang Li Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Reduce affinity use and move into iterator, fix no affinity

2026-02-10T12:34:44+00:00

The evlist__for_each_cpu iterator will call sched_setaffitinity when moving between CPUs to avoid IPIs. If only 1 IPI is saved then this may be unprofitable as the delay to get scheduled may be considerable. This may be particularly true if reading an event group in `perf stat` in interval mode. Move the affinity handling completely into the iterator so that a single evlist__use_affinity can determine whether CPU affinities will be used. For `perf record` the change is minimal as the dummy event and the real event will always make the use of affinities the thing to do. In `perf stat`, tool events are ignored and affinities only used if >1 event on the same CPU occur. Determining if affinities are useful is done by evlist__use_affinity which tests per-event whether the event's PMU benefits from affinity use - it is assumed only perf event using PMUs do. Fix a bug where when there are no affinities that the CPU map iterator may reference a CPU not present in the initial evsel. Fix by making the iterator and non-iterator code common. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Andres Freund Cc: Dapeng Mi Cc: Dr. David Alan Gilbert Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Thomas Richter Cc: Yang Li Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Switch printf("...%s", strerror(errno)) to printf("...%m")

2026-01-14T20:22:50+00:00

strerror() has thread safety issues, strerror_r() requires stack allocated buffers. Code in perf has already been using the "%m" formatting flag that is a widely support glibc extension to print the current errno's description. Expand the usage of this formatting flag and remove usage of strerror()/strerror_r(). Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Haibo Xu Cc: Howard Chu Cc: Ingo Molnar Cc: Jiri Olsa Cc: Leo Yan Cc: Peter Zijlstra Cc: Stephen Brennan Cc: Thomas Falcon Cc: Yunseong Kim Cc: Zhongqiu Han Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Improve handling of termination by signal

2025-12-04T23:44:39+00:00

When interrupting perf stat in repeat mode with a signal the signal is passed to the child process but the repeat doesn't terminate: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] ^Csleep: Interrupt [ perf stat: executing run #3 ... ] [ perf stat: executing run #4 ... ] [ perf stat: executing run #5 ... ] [ perf stat: executing run #6 ... ] [ perf stat: executing run #7 ... ] [ perf stat: executing run #8 ... ] [ perf stat: executing run #9 ... ] [ perf stat: executing run #10 ... ] Performance counter stats for 'sleep 1' (10 runs): 0.9500 +- 0.0512 seconds time elapsed ( +- 5.39% ) 0.01user 0.02system 0:09.53elapsed 0%CPU (0avgtext+0avgdata 18940maxresident)k 29944inputs+0outputs (0major+2629minor)pagefaults 0swaps ``` Terminate the repeated run and give a reasonable exit value: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] [ perf stat: executing run #3 ... ] ^Csleep: Interrupt Performance counter stats for 'sleep 1' (10 runs): 0.680 +- 0.321 seconds time elapsed ( +- 47.16% ) Command exited with non-zero status 130 0.00user 0.01system 0:02.05elapsed 0%CPU (0avgtext+0avgdata 70688maxresident)k 0inputs+0outputs (0major+5002minor)pagefaults 0swaps ``` Note, this also changes the exit value for non-repeat runs when interrupted by a signal. Reported-by: Ingo Molnar Closes: https://lore.kernel.org/lkml/aS5wjmbAM9ka3M2g@gmail.com/ Signed-off-by: Ian Rogers Tested-by: Thomas Richter Signed-off-by: Namhyung Kim

perf stat: When no events, don't report an error if there is none

2025-12-04T08:36:14+00:00

Events may fail to open as no supported CPUs were specified on the command line. In this case a confusing "error" message of "success" can be reported. Let's skip the error in that case. Before: ``` $ perf stat -C2048 -e cycles -- true WARNING: A requested CPU in '2048' is not supported by PMU 'cpu' (CPUs 0-7) for event 'cycles' Error: No supported events found. The sys_perf_event_open() syscall returned with 0 (Success) for event (cpu/unknown-hardware/). "dmesg | grep -i perf" may provide additional information. ``` After: ``` $ perf stat -C2048 -e cycles -- true WARNING: A requested CPU in '2048' is not supported by PMU 'cpu' (CPUs 0-7) for event 'cycles' Error: No supported events found. ``` Signed-off-by: Ian Rogers Tested-by: Thomas Richter Signed-off-by: Namhyung Kim