From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08B51C4646D for ; Sat, 11 Aug 2018 13:50:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A5E4E21A28 for ; Sat, 11 Aug 2018 13:50:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A5E4E21A28 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727513AbeHKQY2 (ORCPT ); Sat, 11 Aug 2018 12:24:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:39808 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727379AbeHKQY2 (ORCPT ); Sat, 11 Aug 2018 12:24:28 -0400 Received: from gandalf.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4124521A2A; Sat, 11 Aug 2018 13:50:12 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.91) (envelope-from ) id 1foUHT-00060R-B3; Sat, 11 Aug 2018 09:50:11 -0400 Message-Id: <20180811135011.244166178@goodmis.org> User-Agent: quilt/0.65 Date: Sat, 11 Aug 2018 09:49:30 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , "Paul E. McKenney" , "Joel Fernandes (Google)" Subject: [for-next][PATCH 02/34] srcu: Add notrace variant of srcu_dereference References: <20180811134928.034373761@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Joel Fernandes (Google)" In the last patch in this series, we are making lockdep register hooks onto the irq_{disable,enable} tracepoints. These tracepoints use the _rcuidle tracepoint variant. In this series we switch the _rcuidle tracepoint callers to use SRCU instead of sched-RCU. Inorder to dereference the pointer to the probe functions, we could call srcu_dereference, however this API will call back into lockdep to check if the lock is held *before* the lockdep probe hooks have a chance to run and annotate the IRQ enabled/disabled state. For this reason we need a notrace variant of srcu_dereference since otherwise we get lockdep splats. This patch adds the needed srcu_dereference_notrace variant. Link: http://lkml.kernel.org/r/20180628182149.226164-3-joel@joelfernandes.org Reviewed-by: Paul E. McKenney Signed-off-by: Joel Fernandes (Google) Signed-off-by: Steven Rostedt (VMware) --- include/linux/srcu.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 3e72a291c401..67135d4a8a30 100644 --- a/include/linux/srcu.h +++ b/include/linux/srcu.h @@ -169,6 +169,11 @@ static inline int srcu_read_lock_held(const struct srcu_struct *sp) */ #define srcu_dereference(p, sp) srcu_dereference_check((p), (sp), 0) +/** + * srcu_dereference_notrace - no tracing and no lockdep calls from here + */ +#define srcu_dereference_notrace(p, sp) srcu_dereference_check((p), (sp), 1) + /** * srcu_read_lock - register a new reader for an SRCU-protected structure. * @sp: srcu_struct in which to register the new reader. -- 2.18.0