lwn.git/tools/perf/tests/perf-time-to-tsc.c, branch docs-fixes

perf test: Switch cycles event to cpu-cycles

2025-10-15T14:59:12+00:00

Without a PMU perf matches an event against any PMU with the event. Unfortunately some PMU drivers advertise a "cycles" event which is typically just a core event. As tests assume a core event, switch to use "cpu-cycles" that avoids the overloaded "cycles" event on troublesome PMUs and is so far not overloaded. Note, on x86 this changes a legacy event into a sysfs one. Signed-off-by: Ian Rogers Tested-by: James Clark Signed-off-by: Namhyung Kim

perf thread_map: Remove uid options

2025-06-09T18:18:18+00:00

Now the target doesn't have a uid, it is handled through BPF filters, remove the uid options to thread_map creation. Tidy up the functions used in tests to avoid passing unused arguments. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250604174545.2853620-11-irogers@google.com Signed-off-by: Namhyung Kim

perf sample: Make user_regs and intr_regs optional

2025-02-13T04:06:11+00:00

The struct dump_regs contains 512 bytes of cache_regs, meaning the two values in perf_sample contribute 1088 bytes of its total 1384 bytes size. Initializing this much memory has a cost reported by Tavian Barnes as about 2.5% when running `perf script --itrace=i0`: https://lore.kernel.org/lkml/d841b97b3ad2ca8bcab07e4293375fb7c32dfce7.1736618095.git.tavianator@tavianator.com/ Adrian Hunter replied that the zero initialization was necessary and couldn't simply be removed. This patch aims to strike a middle ground of still zeroing the perf_sample, but removing 79% of its size by make user_regs and intr_regs optional pointers to zalloc-ed memory. To support the allocation accessors are created for user_regs and intr_regs. To support correct cleanup perf_sample__init and perf_sample__exit functions are created and added throughout the code base. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250113194345.1537821-1-irogers@google.com Signed-off-by: Namhyung Kim

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

perf tools: Move 'struct perf_sample' to a separate header file to disentangle headers

2022-10-31T14:06:41+00:00

Some places were including event.h just to get 'struct perf_sample', move it to a separate place so that we speed up a bit the build. Signed-off-by: Arnaldo Carvalho de Melo

perf test: Fix double word in comments

2022-08-12T19:42:55+00:00

Delete the redundant word "then" in comments. Signed-off-by: shaomin Deng Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20220807074753.7857-1-dengshaomin@cdjrlc.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Do not pass NULL to parse_events()

2022-08-10T17:30:09+00:00

Many cases do not use the extra error information provided by parse_events and instead pass NULL as the struct parse_events_error pointer. Add a wrapper for those cases so that the pointer is never NULL. Signed-off-by: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lore.kernel.org/r/20220809080702.6921-4-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tests: Fix Convert perf time to TSC test for hybrid

2022-07-17T13:57:07+00:00

The test does not always correctly determine the number of events for hybrids, nor allow for more than 1 evsel when parsing. Fix by iterating the events actually created and getting the correct evsel for the events processed. Fixes: d9da6f70eb235110 ("perf tests: Support 'Convert perf time to TSC' test for hybrid") Reviewed-by: Kan Liang Signed-off-by: Adrian Hunter Cc: Ian Rogers Cc: Jin Yao Cc: Jiri Olsa Cc: Namhyung Kim Cc: Thomas Richter Link: https://lore.kernel.org/r/20220713123459.24145-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tests: Stop Convert perf time to TSC test opening events twice

2022-07-17T13:56:58+00:00

Do not call evlist__open() twice. Fixes: 5bb017d4b97a0f13 ("perf test: Fix error message for test case 71 on s390, where it is not supported") Reviewed-by: Kan Liang Signed-off-by: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: Thomas Richter Link: https://lore.kernel.org/r/20220713123459.24145-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf test: Fix error message for test case 71 on s390, where it is not supported

2022-04-22T21:39:34+00:00

Test case 71 'Convert perf time to TSC' is not supported on s390. Subtest 71.1 is skipped with the correct message, but subtest 71.2 is not skipped and fails. The root cause is function evlist__open() called from test__perf_time_to_tsc(). evlist__open() returns -ENOENT because the event cycles:u is not supported by the selected PMU, for example platform s390 on z/VM or an x86_64 virtual machine. The PMU driver returns -ENOENT in this case. This error is leads to the failure. Fix this by returning TEST_SKIP on -ENOENT. Output before: 71: Convert perf time to TSC: 71.1: TSC support: Skip (This architecture does not support) 71.2: Perf time to TSC: FAILED! Output after: 71: Convert perf time to TSC: 71.1: TSC support: Skip (This architecture does not support) 71.2: Perf time to TSC: Skip (perf_read_tsc_conversion is not supported) This also happens on an x86_64 virtual machine: # uname -m x86_64 $ ./perf test -F 71 71: Convert perf time to TSC : 71.1: TSC support : Ok 71.2: Perf time to TSC : FAILED! $ Committer testing: Continues to work on x86_64: $ perf test 71 71: Convert perf time to TSC : 71.1: TSC support : Ok 71.2: Perf time to TSC : Ok $ Fixes: 290fa68bdc458863 ("perf test tsc: Fix error message when not supported") Signed-off-by: Thomas Richter Acked-by: Sumanth Korikkar Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Chengdong Li Cc: chengdongli@tencent.com Cc: Heiko Carstens Cc: Sven Schnelle Cc: Vasily Gorbik Link: https://lore.kernel.org/r/20220420062921.1211825-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo