Commit 86a0a7c5 authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

perf: Move perf_mmap_calc_limits() into both rb and aux branches 



  if (cond) {
    A;
  } else {
    B;
  }
  C;

into

  if (cond) {
    A;
    C;
  } else {
    B;
    C;
  }

Suggested-by: default avatarThomas Gleixner <tglx@linutronix.de>
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/20250812104018.781244099@infradead.org
parent 1ea3e3b0

kernel/events/core.c

+18 −8
Original line number Diff line number Diff line
@@ -7054,6 +7054,16 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) 
			ring_buffer_attach(event, NULL);

		}



		if (!perf_mmap_calc_limits(vma, &user_extra, &extra)) {

			ret = -EPERM;

			goto unlock;

		}



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



		if (vma->vm_flags & VM_WRITE)

			flags |= RING_BUFFER_WRITABLE;



	} else {

		/*

		 * AUX area mapping: if rb->aux_nr_pages != 0, it's already
@@ -7100,7 +7110,6 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) 
			ret = 0;

			goto unlock;

		}

	}



		if (!perf_mmap_calc_limits(vma, &user_extra, &extra)) {

			ret = -EPERM;
@@ -7111,6 +7120,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) 


		if (vma->vm_flags & VM_WRITE)

			flags |= RING_BUFFER_WRITABLE;

	}



	if (!rb) {

		rb = rb_alloc(nr_pages,