kernel/tools/perf/util/evsel.c, branch linux-rolling-lts

perf tools: Fix missing feature check for inherit + SAMPLE_READ

2025-12-18T13:02:57Z

[ Upstream commit 367377f45c0b568882567f797b7b18b263505be7 ] It should also have PERF_SAMPLE_TID to enable inherit and PERF_SAMPLE_READ on recent kernels. Not having _TID makes the feature check wrongly detect the inherit and _READ support. It was reported that the following command failed due to the error in the missing feature check on Intel SPR machines. $ perf record -e '{cpu/mem-loads-aux/S,cpu/mem-loads,ldlat=3/PS}' -- ls Error: Failure to open event 'cpu/mem-loads,ldlat=3/PS' on PMU 'cpu' which will be removed. Invalid event (cpu/mem-loads,ldlat=3/PS) in per-thread mode, enable system wide with '-a'. Reviewed-by: Ian Rogers Fixes: 3b193a57baf15c468 ("perf tools: Detect missing kernel features properly") Reported-and-tested-by: Chen, Zide Closes: https://lore.kernel.org/lkml/20251022220802.1335131-1-zide.chen@intel.com/ Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf record: Add ratio-to-prev term

2025-10-03T19:49:51Z

Provide ratio-to-prev term which allows the user to set the event sample period of two events corresponding to a desired ratio. If using on an Intel x86 platform with Auto Counter Reload support, also set corresponding event's config2 attribute with a bitmask which counters to reset and which counters to sample if the desired ratio is met or exceeded. On other platforms, only the sample period is affected by the ratio-to-prev term. Reviewed-by: Ian Rogers Signed-off-by: Thomas Falcon Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Dapeng Mi Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Refactor retry/skip/fatal error handling

2025-10-03T19:49:51Z

For the sake of Intel topdown events commit 9eac5612da1c9102 ("perf stat: Don't skip failing group events") changed 'perf stat' error handling making it so that more errors were fatal and didn't report "" events. The change outside of topdown events was unintentional. The notion of "fatal" error handling was introduced in commit e0e6a6ca3ac211cc ("perf stat: Factor out open error handling") and refined in commits like commit cb5ef60067c11cc8 ("perf stat: Error out unsupported group leader immediately") to be an approach for avoiding later assertion failures in the code base. This change fixes those issues and removes the notion of a fatal error on an event. If all events fail to open then a fatal error occurs with the previous fatal error message. This seems to best match the notion of supported events and allowing some errors not to stop 'perf stat', while allowing the truly fatal no event case to terminate the tool early. The evsel->errored flag is only used in the stat code but always just meaning !evsel->supported although there is a comment about it being sticky. Force all evsels to be supported in evsel__init and then clear this when evsel__open fails. When an event is tried the supported is set to true again. This simplifies the notion of whether an evsel is broken. In the get_group_fd code, fail to get a group fd when the evsel isn't supported. If the leader isn't supported then it is also expected that there is no group_fd as the leader will have been skipped. Therefore change the BUG_ON test to be on supported rather than skippable. This corrects the assertion errors that were the reason for the previous fatal error handling. Fixes: 9eac5612da1c9102 ("perf stat: Don't skip failing group events") Reviewed-by: James Clark Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Howard Chu Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Link: https://lore.kernel.org/r/20251002220727.1889799-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Ensure the fallback message is always written to

2025-09-19T19:52:24Z

The fallback message is unconditionally printed in places like record__open(). If no fallback is attempted this can lead to printing uninitialized data, crashes, etc. Fixes: c0a54341c0e89333 ("perf evsel: Introduce event fallback method") Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Fix uniquification when PMU given without suffix

2025-09-19T19:50:17Z

The PMU name is appearing twice in: ``` $ perf stat -e uncore_imc_free_running/data_total/ -A true Performance counter stats for 'system wide': CPU0 1.57 MiB uncore_imc_free_running_0/uncore_imc_free_running,data_total/ CPU0 1.58 MiB uncore_imc_free_running_1/uncore_imc_free_running,data_total/ 0.000892376 seconds time elapsed ``` Use the pmu_name_len_no_suffix to avoid this problem. Committer testing: After this patch: root@x1:~# perf stat -e uncore_imc_free_running/data_total/ -A true Performance counter stats for 'system wide': CPU0 1.69 MiB uncore_imc_free_running_0/data_total/ CPU0 1.68 MiB uncore_imc_free_running_1/data_total/ 0.002141605 seconds time elapsed root@x1:~# Fixes: 7d45f402d3117e0b ("perf evlist: Make uniquifying counter names consistent") Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Chun-Tse Shao Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Give warning for broken Intel topdown event grouping

2025-09-12T18:48:12Z

Extend arch_evsel__open_strerror() from just AMD IBS events to Intel core PMU events, to give a message when a slots event isn't a group leader or when a perf metric event is duplicated within an event group. As generating the warning happens after non-arch specific warnings are generated, disable the missing system wide (-a) flag warning for the core PMU. This assumes core PMU events should support per-thread/process and system-wide. Reviewed-by: Dapeng Mi Signed-off-by: Ian Rogers Tested-by: Dapeng Mi Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Greg Kroah-Hartman Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Yoshihiro Furudera Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Avoid container_of on a NULL leader

2025-09-03T15:34:54Z

An evsel should typically have a leader of itself, however, in tests like 'Sample parsing' a NULL leader may occur and the container_of will return a corrupt pointer. Avoid this with an explicit NULL test. Fixes: fba7c86601e2e42d ("libperf: Move 'leader' from tools/perf to perf_evsel::leader") Reviewed-by: James Clark Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Collin Funk Cc: Howard Chu Cc: Ingo Molnar Cc: Jan Polensky Cc: Jiri Olsa Cc: Kan Liang Cc: Li Huafei Cc: Mark Rutland Cc: Nam Cao Cc: Peter Zijlstra Cc: Steinar H. Gunderson Cc: Thomas Gleixner Link: https://lore.kernel.org/r/20250821163820.1132977-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tp_pmu: Factor existing tracepoint logic to new file

2025-07-26T23:31:43Z

Start the creation of a tracepoint PMU abstraction. Tracepoint events don't follow the regular sysfs perf conventions. Eventually the new PMU abstraction will bridge the gap so tracepoint events look more like regular perf ones. Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20250725185202.68671-5-irogers@google.com Signed-off-by: Namhyung Kim

perf sample: Remove arch notion of sample parsing

2025-07-25T17:37:58Z

By definition arch sample parsing and synthesis will inhibit certain kinds of cross-platform record then analysis (report, script, etc.). Remove arch_perf_parse_sample_weight and arch_perf_synthesize_sample_weight replacing with a common implementation. Combine perf_sample p_stage_cyc and retire_lat as weight3 to capture the differing uses regardless of compiled for architecture. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-21-irogers@google.com Signed-off-by: Namhyung Kim

perf env: Remove global perf_env

2025-07-25T17:37:58Z

The global perf_env was used for the host, but if a perf_env wasn't easy to come by it was used in a lot of places where potentially recorded and host data could be confused. Remove the global variable as now the majority of accesses retrieve the perf_env for the host from the session. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-20-irogers@google.com Signed-off-by: Namhyung Kim