perf: Use scoped_guard() for mmap_mutex in perf_mmap()

Mostly just re-indent noise.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://lore.kernel.org/r/20250812104019.838047976@infradead.org

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 3a5fd2b802e4f7e8cdb713bdc4dfb7ef5f4a99d6..41941dfadfcbc756233e5c28f5f620f15e3615b1 100644 (file)
--- 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.