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Date: Wed,  1 May 2024 21:01:08 -0700
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Subject: [PATCH v4 2/6] perf Document: Sysfs event names must be lower or
 upper case
From: Ian Rogers <irogers@google.com>
To: Kan Liang <kan.liang@linux.intel.com>, Thomas Richter <tmricht@linux.ibm.com>, 
	Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>, 
	Arnaldo Carvalho de Melo <acme@kernel.org>, Namhyung Kim <namhyung@kernel.org>, 
	Mark Rutland <mark.rutland@arm.com>, 
	Alexander Shishkin <alexander.shishkin@linux.intel.com>, Jiri Olsa <jolsa@kernel.org>, 
	Bjorn Helgaas <bhelgaas@google.com>, Jonathan Corbet <corbet@lwn.net>, 
	Randy Dunlap <rdunlap@infradead.org>, Jing Zhang <renyu.zj@linux.alibaba.com>, 
	James Clark <james.clark@arm.com>, Ravi Bangoria <ravi.bangoria@amd.com>, 
	linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org
Cc: Ian Rogers <irogers@google.com>
Content-Type: text/plain; charset="UTF-8"

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

Signed-off-by: Ian Rogers <irogers@google.com>
---
 .../ABI/testing/sysfs-bus-event_source-devices-events       | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
index 77de58d03822..e7efeab2ee83 100644
--- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
+++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events
@@ -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>]]...
-- 
2.45.0.rc0.197.gbae5840b3b-goog