kernel/linux.git/tools/lib/perf/evlist.c, branch v6.6.131

perf evlist: Add perf_evlist__go_system_wide() helper

2024-06-12T09:13:02+00:00

commit f6ff1c760431be34e4daaa44f242be911becd998 upstream. 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 Signed-off-by: Greg Kroah-Hartman

libperf evlist: Avoid out-of-bounds access

2024-04-13T11:07:36+00:00

[ Upstream commit 1947b92464c3268381604bbe2ac977a3fd78192f ] 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 Cc: Yang Jihong Signed-off-by: Namhyung Kim Link: https://lore.kernel.org/r/20240229070757.796244-1-irogers@google.com Signed-off-by: Sasha Levin

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

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

2022-09-08T15:17:22+00:00

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 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 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 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 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 [ 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 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 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 [ 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 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216441 Signed-off-by: Adrian Hunter Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20220905114209.8389-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo