From 05a5dd1dfd8fdeee6498875c2d78d4385d627bd6 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 29 Aug 2024 23:51:49 -0700 Subject: [PATCH] perf lock contention: Simplify spinlock check The LCB_F_SPIN bit is used for spinlock, rwlock and optimistic spinning in mutex. In get_tstamp_elem() it needs to check spinlock and rwlock only. As mutex sets the LCB_F_MUTEX, it can check those two bits and reduce the number of operations. Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Cc: Song Liu Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240830065150.1758962-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/bpf_skel/lock_contention.bpf.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/perf/util/bpf_skel/lock_contention.bpf.c b/tools/perf/util/bpf_skel/lock_contention.bpf.c index e8a6f6463019..4b7237e178bd 100644 --- a/tools/perf/util/bpf_skel/lock_contention.bpf.c +++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c @@ -323,8 +323,7 @@ static inline struct tstamp_data *get_tstamp_elem(__u32 flags) struct tstamp_data *pelem; /* Use per-cpu array map for spinlock and rwlock */ - if (flags == (LCB_F_SPIN | LCB_F_READ) || flags == LCB_F_SPIN || - flags == (LCB_F_SPIN | LCB_F_WRITE)) { + if ((flags & (LCB_F_SPIN | LCB_F_MUTEX)) == LCB_F_SPIN) { __u32 idx = 0; pelem = bpf_map_lookup_elem(&tstamp_cpu, &idx); -- 2.50.1