From 831068eed9202ece884ddace8fbb262d900fa1b7 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Wed, 8 Jul 2026 10:53:11 -0700 Subject: [PATCH] perf tests: Restore -p flag to lock contention test Commit ae42a2a2a3ae ("perf tests: Speed up lock contention analysis shell test") in linux-next heavily optimized the test runtimes by switching the workload from the default of 10 process groups down to 1 (`perf bench sched messaging -g 1`). However, this change inadvertently dropped the original `-p` flag, causing the benchmark to default to `socketpair()` instead of `pipe()`. While `socketpair()` still generates some lock events on x86, it fails to trigger enough samples on architectures like s390, causing the test suite to fail due to lack of captured data. Restore the omitted `-p` pipe flag. The test retains the massive speedups achieved through the `-g 1` scaling, while producing a massive density of lock events across all architectures to fully satisfy the BPF trace filtering logic. Fixes: ae42a2a2a3ae ("perf tests: Speed up lock contention analysis shell test") Signed-off-by: Ian Rogers Tested-by: Thomas Richter Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Namhyung Kim --- tools/perf/tests/shell/lock_contention.sh | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/perf/tests/shell/lock_contention.sh b/tools/perf/tests/shell/lock_contention.sh index ba598370be73..5df9a0cd48a3 100755 --- a/tools/perf/tests/shell/lock_contention.sh +++ b/tools/perf/tests/shell/lock_contention.sh @@ -11,7 +11,8 @@ errout=$(mktemp /tmp/__perf_test.errout.XXXXX) # Workload to generate lock contention. # Using 1 group (-g 1) keeps runtime low while generating sufficient lock events. -msg_workload="perf bench sched messaging -g 1" +# We include -p (pipes) because socketpairs don't generate enough lock events on s390. +msg_workload="perf bench sched messaging -g 1 -p" cleanup() { rm -f ${perfdata}