kernel/events/core.c

4988 static void ring_buffer_attach(struct perf_event *event,
5206 		ring_buffer_attach(event, NULL);
6190 static void ring_buffer_attach(struct perf_event *event,
6363 	ring_buffer_attach(event, NULL);
6399 			ring_buffer_attach(event, NULL);
6550 			ring_buffer_attach(event, NULL);
6616 		ring_buffer_attach(event, rb);
8105 	 * however this may race with ring_buffer_attach() (through set_output),
8107 	 * So ring_buffer_attach() has to stop an aux event before re-assigning
12327 	ring_buffer_attach(event, rb);