From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754307AbaCKBF1 (ORCPT ); Mon, 10 Mar 2014 21:05:27 -0400 Received: from mail.efficios.com ([78.47.125.74]:42551 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752714AbaCKBFZ (ORCPT ); Mon, 10 Mar 2014 21:05:25 -0400 From: Mathieu Desnoyers To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Ingo Molnar , Frederic Weisbecker , Andrew Morton Subject: [PATCH 2/2] Tracepoint API doc update: tracepoint_probe_register() return value Date: Mon, 10 Mar 2014 21:04:58 -0400 Message-Id: <1394499898-1537-2-git-send-email-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1394499898-1537-1-git-send-email-mathieu.desnoyers@efficios.com> References: <1394499898-1537-1-git-send-email-mathieu.desnoyers@efficios.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Describe the return values of tracepoint_probe_register(), including -ENODEV added by commit: Author: Steven Rostedt tracing: Warn if a tracepoint is not set via debugfs Signed-off-by: Mathieu Desnoyers CC: Steven Rostedt CC: Ingo Molnar CC: Frederic Weisbecker CC: Andrew Morton --- kernel/tracepoint.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 49cb94e..0839258 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -378,7 +378,17 @@ tracepoint_add_probe(const char *name, void *probe, void *data) * @probe: probe handler * @data: probe private data * - * Returns 0 if ok, error value on error. + * Returns: + * - 0 if the probe was successfully registered, and tracepoint + * callsites are currently loaded for that probe, + * - -ENODEV if the probe was successfully registered, but no tracepoint + * callsite is currently loaded for that probe, + * - other negative error value on error. + * + * When tracepoint_probe_register() returns either 0 or -ENODEV, + * parameters @name, @probe, and @data may be used by the tracepoint + * infrastructure until the probe is unregistered. + * * The probe address must at least be aligned on the architecture pointer size. */ int tracepoint_probe_register(const char *name, void *probe, void *data) -- 1.7.10.4