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=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,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 B77F9C7112F for ; Mon, 21 Jan 2019 11:32:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8FF7020861 for ; Mon, 21 Jan 2019 11:32:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728272AbfAULcQ (ORCPT ); Mon, 21 Jan 2019 06:32:16 -0500 Received: from terminus.zytor.com ([198.137.202.136]:50117 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727287AbfAULcQ (ORCPT ); Mon, 21 Jan 2019 06:32:16 -0500 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x0LBVxJW2496701 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Mon, 21 Jan 2019 03:32:00 -0800 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x0LBVxBb2496698; Mon, 21 Jan 2019 03:31:59 -0800 Date: Mon, 21 Jan 2019 03:31:59 -0800 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Frederic Weisbecker Message-ID: Cc: mingo@kernel.org, will.deacon@arm.com, paulmck@linux.vnet.ibm.com, tglx@linutronix.de, peterz@infradead.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, hpa@zytor.com, frederic@kernel.org, akpm@linux-foundation.org Reply-To: paulmck@linux.vnet.ibm.com, tglx@linutronix.de, mingo@kernel.org, will.deacon@arm.com, torvalds@linux-foundation.org, peterz@infradead.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, hpa@zytor.com, frederic@kernel.org In-Reply-To: <1545973321-24422-3-git-send-email-frederic@kernel.org> References: <1545973321-24422-3-git-send-email-frederic@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:locking/core] locking/lockdep: Provide enum lock_usage_bit mask names Git-Commit-ID: bba2a8f1f974a45ca6ceaf688b2be7bc1c418a2f X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: bba2a8f1f974a45ca6ceaf688b2be7bc1c418a2f Gitweb: https://git.kernel.org/tip/bba2a8f1f974a45ca6ceaf688b2be7bc1c418a2f Author: Frederic Weisbecker AuthorDate: Fri, 28 Dec 2018 06:02:01 +0100 Committer: Ingo Molnar CommitDate: Mon, 21 Jan 2019 11:18:56 +0100 locking/lockdep: Provide enum lock_usage_bit mask names It makes the code more self-explanatory and tells throughout the code what magic number refers to: - state (Hardirq/Softirq) - direction (used in or enabled above state) - read or write We can even remove some comments that were compensating for the lack of those constant names. Signed-off-by: Frederic Weisbecker Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Link: https://lkml.kernel.org/r/1545973321-24422-3-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar --- kernel/locking/lockdep.c | 33 +++++++++++---------------------- kernel/locking/lockdep_internals.h | 4 ++++ 2 files changed, 15 insertions(+), 22 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 1dcd8341e35b..608f74ed8bb9 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1624,29 +1624,18 @@ static const char *state_rnames[] = { static inline const char *state_name(enum lock_usage_bit bit) { - return (bit & 1) ? state_rnames[bit >> 2] : state_names[bit >> 2]; + return (bit & LOCK_USAGE_READ_MASK) ? state_rnames[bit >> 2] : state_names[bit >> 2]; } static int exclusive_bit(int new_bit) { - /* - * USED_IN - * USED_IN_READ - * ENABLED - * ENABLED_READ - * - * bit 0 - write/read - * bit 1 - used_in/enabled - * bit 2+ state - */ - - int state = new_bit & ~3; - int dir = new_bit & 2; + int state = new_bit & LOCK_USAGE_STATE_MASK; + int dir = new_bit & LOCK_USAGE_DIR_MASK; /* * keep state, bit flip the direction and strip read. */ - return state | (dir ^ 2); + return state | (dir ^ LOCK_USAGE_DIR_MASK); } static int check_irq_usage(struct task_struct *curr, struct held_lock *prev, @@ -2662,8 +2651,8 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, enum lock_usage_bit new_bit) { int excl_bit = exclusive_bit(new_bit); - int read = new_bit & 1; - int dir = new_bit & 2; + int read = new_bit & LOCK_USAGE_READ_MASK; + int dir = new_bit & LOCK_USAGE_DIR_MASK; /* * mark USED_IN has to look forwards -- to ensure no dependency @@ -2687,19 +2676,19 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, * states. */ if ((!read || !dir || STRICT_READ_CHECKS) && - !usage(curr, this, excl_bit, state_name(new_bit & ~1))) + !usage(curr, this, excl_bit, state_name(new_bit & ~LOCK_USAGE_READ_MASK))) return 0; /* * Check for read in write conflicts */ if (!read) { - if (!valid_state(curr, this, new_bit, excl_bit + 1)) + if (!valid_state(curr, this, new_bit, excl_bit + LOCK_USAGE_READ_MASK)) return 0; if (STRICT_READ_CHECKS && - !usage(curr, this, excl_bit + 1, - state_name(new_bit + 1))) + !usage(curr, this, excl_bit + LOCK_USAGE_READ_MASK, + state_name(new_bit + LOCK_USAGE_READ_MASK))) return 0; } @@ -2723,7 +2712,7 @@ mark_held_locks(struct task_struct *curr, enum lock_usage_bit base_bit) hlock = curr->held_locks + i; if (hlock->read) - hlock_bit += 1; /* READ */ + hlock_bit += LOCK_USAGE_READ_MASK; BUG_ON(hlock_bit >= LOCK_USAGE_STATES); diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index 88c847a41c8a..2ebb9d0ea91c 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -22,6 +22,10 @@ enum lock_usage_bit { LOCK_USAGE_STATES }; +#define LOCK_USAGE_READ_MASK 1 +#define LOCK_USAGE_DIR_MASK 2 +#define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK)) + /* * Usage-state bitmasks: */