perf Documentation: Clarify sysfs event names characters

Specify that perf event names in sysfs must not contain mixed lower and
upper case characters and that they may contain numbers, ".", "_",
or "-" as well.

Fixes: 785623ee85 ("perf Document: Sysfs event names must be lower or upper case")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20240513192439.18473-1-rdunlap@infradead.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Randy Dunlap 2024-05-13 12:24:39 -07:00 committed by Arnaldo Carvalho de Melo
parent d52af4b8c6
commit b031fe8351

View File

@ -37,11 +37,13 @@ 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
As performance monitoring event names are case insensitive
in the perf tool, the perf tool only looks for all lower
case or all 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.
name of the event here is either completely lower or upper
case, with no mixed-case characters. Numbers, '.', '_', and
'-' are also allowed.
File contents: