[PATCH v2 2/4] perf docs: substitute CAP_SYS_ADMIN with CAP_PERFMON where needed
Arnaldo Carvalho de Melo
arnaldo.melo at gmail.com
Thu Apr 23 13:22:01 UTC 2020
Em Wed, Apr 22, 2020 at 05:44:53PM +0300, Alexey Budankov escreveu:
> Substitute CAP_SYS_ADMIN with CAP_PERFMON in the docs where admin
> is mentioned. CAP_SYS_ADMIN still works in keeping with user space
> backward compatibility approach.
Same issue as with the previous patch, the documentation is for the
tool, that may be used in older kernels, so we need to clarify that
CAP_PERFMON requires updating libcap and the kernel, if that isn't
possible, then CAP_SYS_ADMIN is needed.
> Signed-off-by: Alexey Budankov <alexey.budankov at linux.intel.com>
> tools/perf/Documentation/perf-intel-pt.txt | 2 +-
> tools/perf/design.txt | 3 +--
> 2 files changed, 2 insertions(+), 3 deletions(-)
> diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt
> index 456fdcbf26ac..176597be0755 100644
> --- a/tools/perf/Documentation/perf-intel-pt.txt
> +++ b/tools/perf/Documentation/perf-intel-pt.txt
> @@ -687,7 +687,7 @@ The v4.2 kernel introduced support for a context switch metadata event,
> PERF_RECORD_SWITCH, which allows unprivileged users to see when their processes
> are scheduled out and in, just not by whom, which is left for the
> PERF_RECORD_SWITCH_CPU_WIDE, that is only accessible in system wide context,
> -which in turn requires CAP_SYS_ADMIN.
> +which in turn requires CAP_PERFMON.
> Please see the 45ac1403f564 ("perf: Add PERF_RECORD_SWITCH to indicate context
> switches") commit, that introduces these metadata events for further info.
> diff --git a/tools/perf/design.txt b/tools/perf/design.txt
> index a42fab308ff6..6fd879440c40 100644
> --- a/tools/perf/design.txt
> +++ b/tools/perf/design.txt
> @@ -258,8 +258,7 @@ gets schedule to. Per task counters can be created by any user, for
> their own tasks.
> A 'pid == -1' and 'cpu == x' counter is a per CPU counter that counts
> -all events on CPU-x. Per CPU counters need CAP_PERFMON or CAP_SYS_ADMIN
> +all events on CPU-x. Per CPU counters need CAP_PERFMON privilege.
> The 'flags' parameter is currently unused and must be zero.
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