From d23a6dbc0a71741eb7b141fdc04e31360fba46ef Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 12 Aug 2025 12:39:11 +0200 Subject: [PATCH] perf: Use scoped_guard() for mmap_mutex in perf_mmap() Mostly just re-indent noise. Suggested-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Lorenzo Stoakes Link: https://lore.kernel.org/r/20250812104019.838047976@infradead.org --- kernel/events/core.c | 35 ++++++++++++++--------------------- 1 file changed, 14 insertions(+), 21 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 3a5fd2b802e4f..41941dfadfcbc 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7146,30 +7146,23 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) if (vma_size != PAGE_SIZE * nr_pages) return -EINVAL; - mutex_lock(&event->mmap_mutex); - ret = -EINVAL; + scoped_guard (mutex, &event->mmap_mutex) { + /* + * This relies on __pmu_detach_event() taking mmap_mutex after marking + * the event REVOKED. Either we observe the state, or __pmu_detach_event() + * will detach the rb created here. + */ + if (event->state <= PERF_EVENT_STATE_REVOKED) + return -ENODEV; - /* - * This relies on __pmu_detach_event() taking mmap_mutex after marking - * the event REVOKED. Either we observe the state, or __pmu_detach_event() - * will detach the rb created here. - */ - if (event->state <= PERF_EVENT_STATE_REVOKED) { - ret = -ENODEV; - goto unlock; + if (vma->vm_pgoff == 0) + ret = perf_mmap_rb(vma, event, nr_pages); + else + ret = perf_mmap_aux(vma, event, nr_pages); + if (ret) + return ret; } - if (vma->vm_pgoff == 0) - ret = perf_mmap_rb(vma, event, nr_pages); - else - ret = perf_mmap_aux(vma, event, nr_pages); - -unlock: - mutex_unlock(&event->mmap_mutex); - - if (ret) - return ret; - /* * Since pinned accounting is per vm we cannot allow fork() to copy our * vma. -- 2.47.3