mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-02-17 01:56:36 -05:00
2cc7aa995c
For the sake of Intel topdown events commit9eac5612da("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 "<not supported>" events. The change outside of topdown events was unintentional. The notion of "fatal" error handling was introduced in commite0e6a6ca3a("perf stat: Factor out open error handling") and refined in commits like commitcb5ef60067("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:9eac5612da("perf stat: Don't skip failing group events") Reviewed-by: James Clark <james.clark@linaro.org> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Chun-Tse Shao <ctshao@google.com> Cc: Dapeng Mi <dapeng1.mi@linux.intel.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Falcon <thomas.falcon@intel.com> Link: https://lore.kernel.org/r/20251002220727.1889799-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.