kernel/linux.git/tools/perf/util/pmu.l, branch v7.1

perf pmu: Make parser reentrant

2023-04-07T00:40:28+00:00

By default bison uses global state for compatibility with yacc. Make the parser reentrant so that it may be used in asynchronous and multithreaded situations. Signed-off-by: Ian Rogers Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Gaosheng Cui Cc: German Gomez Cc: Ingo Molnar Cc: James Clark Cc: Jing Zhang Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Rob Herring Cc: Sean Christopherson Cc: Suzuki Poulouse Link: https://lore.kernel.org/r/20230406065224.2553640-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf: Skip and warn on unknown format 'configN' attrs

2022-10-14T15:23:09+00:00

If the kernel exposes a new perf_event_attr field in a format attr, perf will return an error stating the specified PMU can't be found. For example, a format attr with 'config3:0-63' causes an error as config3 is unknown to perf. This causes a compatibility issue between a newer kernel with older perf tool. Before this change with a kernel adding 'config3' I get: $ perf record -e arm_spe// -- true event syntax error: 'arm_spe//' \___ Cannot find PMU `arm_spe'. Missing kernel support? Run 'perf list' for a list of valid events Usage: perf record [] [] or: perf record [] -- [] -e, --event event selector. use 'perf list' to list available events After this change, I get: $ perf record -e arm_spe// -- true WARNING: 'arm_spe_0' format 'inv_event_filter' requires 'perf_event_attr::config3' which is not supported by this version of perf! [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.091 MB perf.data ] To support unknown configN formats, rework the YACC implementation to pass any config[0-9]+ format to perf_pmu__new_format() to handle with a warning. Reviewed-by: Namhyung Kim Signed-off-by: Rob Herring Tested-by: Leo Yan Cc: Alexander Shishkin Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Mark Rutland Cc: Peter Zijlstra Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220914-arm-perf-tool-spe1-2-v2-v4-1-83c098e6212e@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add perf pmu object to access pmu format definition

2012-03-16T17:29:35+00:00

Adding pmu object which provides interface to pmu's sysfs event format definition located at: ${sysfs_mount}/bus/event_source/devices/${pmu}/format Following interface is exported: struct perf_pmu* perf_pmu__find(char *name); - this function returns pmu object, which is then passed as a handle to other interface functions int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr, struct list_head *head_terms); - this function configures perf_event_attr struct based on pmu's format definitions and config terms data, containined in head_terms list. Parser generator is used to retrive the pmu's format definition. The generated parser is part of the patch. Added makefile rule 'pmu-parser' to generate the parser code out of the bison/flex sources. Added builtin test 'Test perf pmu format parsing', which could be run like: perf test pmu Acked-by: Peter Zijlstra Signed-off-by: Jiri Olsa Link: http://lkml.kernel.org/n/tip-errz96u1668gj9wlop1zhpht@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo