lkml.org 
[lkml]   [2023]   [Oct]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] perf tests: test_arm_coresight: Simplify source iteration
Date
There are two reasons to do this, firstly there is a shellcheck warning
in cs_etm_dev_name(), which can be completely deleted. And secondly the
current iteration method doesn't support systems with both ETE and ETM
because it picks one or the other. There isn't a known system with this
configuration, but it could happen in the future.

Iterating over all the sources for each CPU can be done by going through
/sys/bus/event_source/devices/cs_etm/cpu* and following the symlink back
to the Coresight device in /sys/bus/coresight/devices. This will work
whether the device is ETE, ETM or any future name, and is much simpler
and doesn't require any hard coded version numbers

Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: James Clark <james.clark@arm.com>
---

This was discussed here previously:
https://lore.kernel.org/all/20230929041133.95355-2-atrajeev@linux.vnet.ibm.com/

I chose not to add a fixes tag like the original because shellcheck
isn't part of the build so it doesn't really fix any real issue yet and
is just a refactor.

tools/perf/tests/shell/test_arm_coresight.sh | 17 +++--------------
1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/tools/perf/tests/shell/test_arm_coresight.sh b/tools/perf/tests/shell/test_arm_coresight.sh
index fe78c4626e45..65dd85207125 100755
--- a/tools/perf/tests/shell/test_arm_coresight.sh
+++ b/tools/perf/tests/shell/test_arm_coresight.sh
@@ -11,19 +11,6 @@

glb_err=0

-cs_etm_dev_name() {
- cs_etm_path=$(find /sys/bus/event_source/devices/cs_etm/ -name cpu* -print -quit)
- trcdevarch=$(cat ${cs_etm_path}/mgmt/trcdevarch)
- archhver=$((($trcdevarch >> 12) & 0xf))
- archpart=$(($trcdevarch & 0xfff))
-
- if [ $archhver -eq 5 -a "$(printf "0x%X\n" $archpart)" = "0xA13" ] ; then
- echo "ete"
- else
- echo "etm"
- fi
-}
-
skip_if_no_cs_etm_event() {
perf list | grep -q 'cs_etm//' && return 0

@@ -149,7 +136,9 @@ arm_cs_iterate_devices() {

arm_cs_etm_traverse_path_test() {
# Iterate for every ETM device
- for dev in /sys/bus/coresight/devices/$(cs_etm_dev_name)*; do
+ for dev in /sys/bus/event_source/devices/cs_etm/cpu*; do
+ # Canonicalize the path
+ dev=`readlink -f $dev`

# Find the ETM device belonging to which CPU
cpu=`cat $dev/cpu`
--
2.34.1
\
 
 \ /
  Last update: 2023-10-23 15:17    [W:0.037 / U:1.180 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site