diff options
| author | Dmitry Ilvokhin <d@ilvokhin.com> | 2026-08-04 07:15:44 +0000 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-08-07 17:58:10 +0200 |
| commit | b359800c6970cb653d41ed2af18fd8e95dbb822f (patch) | |
| tree | eeb7f6dc911982d69ab277296faec8fdaee8043f | |
| parent | f7e2cb6d495aa1a88368650970a230b45870859b (diff) | |
| download | linux-next-b359800c6970cb653d41ed2af18fd8e95dbb822f.tar.gz linux-next-b359800c6970cb653d41ed2af18fd8e95dbb822f.zip | |
tracing/lock: Use TRACE_EVENT_FN() for contended_release
queued_spin_unlock() gates its contended_release trace call behind a
static branch, so a NOP sits on the unlock path even while the
tracepoint is disabled. Removing that requires replacing the unlock
implementation only while contended_release is enabled, which needs a
callback when the tracepoint is toggled.
Convert contended_release to TRACE_EVENT_FN() and add weak no-op
arch_contended_release_trace_reg()/arch_contended_release_trace_unreg()
hooks.
The default hooks are empty, so this is a no-op until an architecture
overrides them.
No functional change intended.
Signed-off-by: Dmitry Ilvokhin <d@ilvokhin.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juergen Gross <jgross@suse.com>
Link: https://patch.msgid.link/1c2fcccfb584c075c02890c484f22c76a1948bf1.1785778551.git.d@ilvokhin.com
| -rw-r--r-- | include/trace/events/lock.h | 10 | ||||
| -rw-r--r-- | kernel/locking/mutex.c | 4 |
2 files changed, 12 insertions, 2 deletions
diff --git a/include/trace/events/lock.h b/include/trace/events/lock.h index 1ded869cd619..b1d5b18c4514 100644 --- a/include/trace/events/lock.h +++ b/include/trace/events/lock.h @@ -137,7 +137,11 @@ TRACE_EVENT(contention_end, TP_printk("%p (ret=%d)", __entry->lock_addr, __entry->ret) ); -TRACE_EVENT(contended_release, +/* kernel/locking/mutex.c */ +int arch_contended_release_trace_reg(void); +void arch_contended_release_trace_unreg(void); + +TRACE_EVENT_FN(contended_release, TP_PROTO(void *lock), @@ -151,7 +155,9 @@ TRACE_EVENT(contended_release, __entry->lock_addr = lock; ), - TP_printk("%p", __entry->lock_addr) + TP_printk("%p", __entry->lock_addr), + + arch_contended_release_trace_reg, arch_contended_release_trace_unreg ); #endif /* _TRACE_LOCK_H */ diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 8a85912d7ee6..942a939cee95 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -1272,6 +1272,10 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(contention_begin); EXPORT_TRACEPOINT_SYMBOL_GPL(contention_end); EXPORT_TRACEPOINT_SYMBOL_GPL(contended_release); +__weak int arch_contended_release_trace_reg(void) { return 0; } + +__weak void arch_contended_release_trace_unreg(void) { } + /** * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0 * @cnt: the atomic which we are to dec |