Commit 394570b7 authored Oct 31, 2013 by Peter Zijlstra Committed by Ingo Molnar Nov 06, 2013

perf: Update a stale comment

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: james.hogan@imgtec.com
Cc: Vince Weaver <vince@deater.net>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Anton Blanchard <anton@samba.org>
Link: http://lkml.kernel.org/n/tip-9s5mze78gmlz19agt39i8rii@git.kernel.org

Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 524feca5

kernel/events/ring_buffer.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -85,8 +85,8 @@ static void perf_output_put_handle(struct perf_output_handle *handle)
		rb->user_page->data_head = head;

		/*
		* Now check if we missed an update, rely on the (compiler)
		* barrier in atomic_dec_and_test() to re-read rb->head.
		* Now check if we missed an update -- rely on previous implied
		* compiler barriers to force a re-read.
		*/
		if (unlikely(head != local_read(&rb->head))) {
		local_inc(&rb->nest);