perf Document: Sysfs event names must be lower or upper case

To avoid directory scans in perf it is going to be assumed that sysfs
event names are either lower or upper case.

Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lore.kernel.org/r/20240502213507.2339733-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ian Rogers 2024-05-02 14:35:03 -07:00 committed by Arnaldo Carvalho de Melo
parent 97c48ea8ff
commit 785623ee85

View File

@ -37,6 +37,12 @@ Description: Per-pmu performance monitoring events specific to the running syste
performance monitoring event supported by the <pmu>. The name
of the file is the name of the event.
As performance monitoring event names are case
insensitive in the perf tool, the perf tool only looks
for lower or upper case event names in sysfs to avoid
scanning the directory. It is therefore required the
name of the event here is either lower or upper case.
File contents:
<term>[=<value>][,<term>[=<value>]]...