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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC868C7EE2E for ; Mon, 15 May 2023 17:35:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244314AbjEORfR (ORCPT ); Mon, 15 May 2023 13:35:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54480 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244313AbjEORev (ORCPT ); Mon, 15 May 2023 13:34:51 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A32344C9E7 for ; Mon, 15 May 2023 10:33:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 14B2F62D76 for ; Mon, 15 May 2023 17:33:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A10AC433EF; Mon, 15 May 2023 17:33:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1684171981; bh=1O3SMvTGFm3hQCJ79tdKQ9yjpHspQL5nzyUZz/PHxGs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J8GZpNs0gA2/IV6OgkDcs4wgtpaS0dZ4wVGK0HffdHST7Mk6uiFVXmLVx9vcJsqws rQjoVUFhWWk9vhDW3/dUedOh4oSBY1j0puZD/ClUxoqmX7MBZb+NsU8/0/3iag1/2m sd8lirSNNU+GBA0P+PzR5oaALfUMl/JDl4GBSFrg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tim Murray , John Stultz , "Peter Zijlstra (Intel)" , Waiman Long Subject: [PATCH 5.15 118/134] locking/rwsem: Add __always_inline annotation to __down_read_common() and inlined callers Date: Mon, 15 May 2023 18:29:55 +0200 Message-Id: <20230515161707.067231801@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230515161702.887638251@linuxfoundation.org> References: <20230515161702.887638251@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: John Stultz commit 92cc5d00a431e96e5a49c0b97e5ad4fa7536bd4b upstream. Apparently despite it being marked inline, the compiler may not inline __down_read_common() which makes it difficult to identify the cause of lock contention, as the blocked function in traceevents will always be listed as __down_read_common(). So this patch adds __always_inline annotation to the common function (as well as the inlined helper callers) to force it to be inlined so the blocking function will be listed (via Wchan) in traceevents. Fixes: c995e638ccbb ("locking/rwsem: Fold __down_{read,write}*()") Reported-by: Tim Murray Signed-off-by: John Stultz Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Waiman Long Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20230503023351.2832796-1-jstultz@google.com Signed-off-by: Greg Kroah-Hartman --- kernel/locking/rwsem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -1221,7 +1221,7 @@ static struct rw_semaphore *rwsem_downgr /* * lock for reading */ -static inline int __down_read_common(struct rw_semaphore *sem, int state) +static __always_inline int __down_read_common(struct rw_semaphore *sem, int state) { int ret = 0; long count; @@ -1239,17 +1239,17 @@ out: return ret; } -static inline void __down_read(struct rw_semaphore *sem) +static __always_inline void __down_read(struct rw_semaphore *sem) { __down_read_common(sem, TASK_UNINTERRUPTIBLE); } -static inline int __down_read_interruptible(struct rw_semaphore *sem) +static __always_inline int __down_read_interruptible(struct rw_semaphore *sem) { return __down_read_common(sem, TASK_INTERRUPTIBLE); } -static inline int __down_read_killable(struct rw_semaphore *sem) +static __always_inline int __down_read_killable(struct rw_semaphore *sem) { return __down_read_common(sem, TASK_KILLABLE); }