Commit 191759e5 authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

perf: Make RB allocation branch self sufficient 



Ensure @rb usage doesn't extend out of the branch block.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarLorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://lore.kernel.org/r/20250812104019.605285302@infradead.org
parent 2aee3768

kernel/events/core.c

+1 −5
Original line number Diff line number Diff line
@@ -7116,8 +7116,6 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) 
				 * multiple times.

				 */

				ret = 0;

				/* We need the rb to map pages. */

				rb = event->rb;

				perf_mmap_account(vma, user_extra, extra);

				atomic_inc(&event->mmap_count);

				goto unlock;
@@ -7136,8 +7134,6 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) 
			goto unlock;

		}



		WARN_ON(!rb && event->rb);



		if (vma->vm_flags & VM_WRITE)

			flags |= RING_BUFFER_WRITABLE;
@@ -7190,7 +7186,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) 
	 * full cleanup in this case and therefore does not invoke

	 * vmops::close().

	 */

	ret = map_range(rb, vma);

	ret = map_range(event->rb, vma);

	if (ret)

		perf_mmap_close(vma);