[PATCH] trace_branch: use per-cpu counters for correct/incorrect stats
From: Martin Weiss <hidden>
Date: 2026-06-29 09:59:04
Also in:
lkml
Subsystem:
the rest, tracing · Maintainers:
Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Replace per-task counters with per-cpu increments to avoid race conditions in the branch profiler fast path. Fixes FIXME about atomicity. Signed-off-by: Martin Weiss <redacted> --- kernel/trace/trace_branch.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index d8e97ad798f0..960bcb3d7dbf 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c@@ -213,11 +213,11 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, */ trace_likely_condition(f, val, expect); - /* FIXME: Make this atomic! */ + /* use per-cpu counters to avoid contention */ if (val == expect) - f->data.correct++; + this_cpu_inc(f->data.correct); else - f->data.incorrect++; + this_cpu_inc(f->data.incorrect); user_access_restore(flags); }
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2.54.0