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=-20.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,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 684CAC4361B for ; Wed, 9 Dec 2020 18:42:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E27BA23B77 for ; Wed, 9 Dec 2020 18:42:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728625AbgLISmt (ORCPT ); Wed, 9 Dec 2020 13:42:49 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:48296 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726471AbgLISja (ORCPT ); Wed, 9 Dec 2020 13:39:30 -0500 Date: Wed, 09 Dec 2020 18:38:46 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1607539127; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=h58TKYvNHpzV3AhfDSJuV1aUN0jkFKSx4mzxkZx/Wa4=; b=NOMRyrkvfSEuq97xZl0ytwPiTp1oC/15nw55oqH/bi6Pzcxeq1co6vkxb+M0MGOVluh95J 5oGOfaDSZmmq2blWpDvI3svuCHr6HUCWYf2nFDx34+belBS8l2J6ggmJQnnmwdmq097WgL h2lw/yKAtXn82R/jQi+T41zlrCXPVdYhyBDKURTv0riweLQOIV/fypq2jdzlyGSjCaPpPR ZA/S1GVadFbxe40lbbf577B195y3e/bp5jqTaKd6af4N6mMStBuP5gdAMkoaWaCDGK1j5I SSeDegTvNXrVj1ORla9M3OruhOmwhHTgBd91fDs2djxbk/grmDO7q4J9XCuRxA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1607539127; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=h58TKYvNHpzV3AhfDSJuV1aUN0jkFKSx4mzxkZx/Wa4=; b=pIgOrgth4yWrPsPFu3uR22I8kbQK85aikx1/uiTtXpoEN9aMXzpLgGUPs/BXkpjS9HPhcp 3hySZdhJIscLImBA== From: "tip-bot2 for Ahmed S. Darwish" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/core] seqlock: kernel-doc: Specify when preemption is automatically altered Cc: "Ahmed S. Darwish" , "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: MIME-Version: 1.0 Message-ID: <160753912635.3364.4993279338737835663.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the locking/core branch of tip: Commit-ID: cb262935a166bdef0ccfe6e2adffa00c0f2d038a Gitweb: https://git.kernel.org/tip/cb262935a166bdef0ccfe6e2adffa00c0f2d038a Author: Ahmed S. Darwish AuthorDate: Sun, 06 Dec 2020 17:21:43 +01:00 Committer: Peter Zijlstra CommitterDate: Wed, 09 Dec 2020 17:08:49 +01:00 seqlock: kernel-doc: Specify when preemption is automatically altered The kernel-doc annotations for sequence counters write side functions are incomplete: they do not specify when preemption is automatically disabled and re-enabled. This has confused a number of call-site developers. Fix it. Signed-off-by: Ahmed S. Darwish Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/CAHk-=wikhGExmprXgaW+MVXG1zsGpztBbVwOb23vetk41EtTBQ@mail.gmail.com --- include/linux/seqlock.h | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index 235cbc6..2f7bb92 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -456,6 +456,8 @@ static inline int do_read_seqcount_retry(const seqcount_t *s, unsigned start) /** * raw_write_seqcount_begin() - start a seqcount_t write section w/o lockdep * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants + * + * Context: check write_seqcount_begin() */ #define raw_write_seqcount_begin(s) \ do { \ @@ -475,6 +477,8 @@ static inline void do_raw_write_seqcount_begin(seqcount_t *s) /** * raw_write_seqcount_end() - end a seqcount_t write section w/o lockdep * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants + * + * Context: check write_seqcount_end() */ #define raw_write_seqcount_end(s) \ do { \ @@ -498,6 +502,7 @@ static inline void do_raw_write_seqcount_end(seqcount_t *s) * @subclass: lockdep nesting level * * See Documentation/locking/lockdep-design.rst + * Context: check write_seqcount_begin() */ #define write_seqcount_begin_nested(s, subclass) \ do { \ @@ -519,11 +524,10 @@ static inline void do_write_seqcount_begin_nested(seqcount_t *s, int subclass) * write_seqcount_begin() - start a seqcount_t write side critical section * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants * - * write_seqcount_begin opens a write side critical section of the given - * seqcount_t. - * - * Context: seqcount_t write side critical sections must be serialized and - * non-preemptible. If readers can be invoked from hardirq or softirq + * Context: sequence counter write side sections must be serialized and + * non-preemptible. Preemption will be automatically disabled if and + * only if the seqcount write serialization lock is associated, and + * preemptible. If readers can be invoked from hardirq or softirq * context, interrupts or bottom halves must be respectively disabled. */ #define write_seqcount_begin(s) \ @@ -545,7 +549,8 @@ static inline void do_write_seqcount_begin(seqcount_t *s) * write_seqcount_end() - end a seqcount_t write side critical section * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants * - * The write section must've been opened with write_seqcount_begin(). + * Context: Preemption will be automatically re-enabled if and only if + * the seqcount write serialization lock is associated, and preemptible. */ #define write_seqcount_end(s) \ do { \