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=-10.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 A17C4C43387 for ; Fri, 28 Dec 2018 05:02:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6EF7421902 for ; Fri, 28 Dec 2018 05:02:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545973337; bh=XKV5OBswjcoUlEHNzPzPwkeCRzdC8ws0ndr0j2F/Jn4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=pk1oQOesKo4L3n47DdgTkCZpjV38/qFIObcGq8HU8aNuEPEbfTv0y762ITBrDzRIf co8n3/vNer8VGcItucVuPDqIiQTPXyOj+NWUl4LGK1bx4auyohwtv+m7t6a/Zc9ij+ uI6Uz1jdExiXO8njSoCe1gh9/sSeUGiam72GymJU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727517AbeL1FCQ (ORCPT ); Fri, 28 Dec 2018 00:02:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:59390 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726871AbeL1FCN (ORCPT ); Fri, 28 Dec 2018 00:02:13 -0500 Received: from lerouge.suse.de (lfbn-ncy-1-241-207.w83-194.abo.wanadoo.fr [83.194.85.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1FF4E21901; Fri, 28 Dec 2018 05:02:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545973332; bh=XKV5OBswjcoUlEHNzPzPwkeCRzdC8ws0ndr0j2F/Jn4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IsipIGL3sf4EoCLcNRODelIlS8CwC/9f96aRFxLBlUHKD15zPqa5o0552ITVyk30g OKO1brlqTH2YL4e0NTNEbnfsA/Gx8cDxlSc/UbsBaDb9Dk1IB+njocdD20PPNFJsNL hks0s5X74JRS7gFDFTBhy63bAmU03xQytkAsEt8k= From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Ingo Molnar , Peter Zijlstra Subject: [PATCH 2/2] locking/lockdep: Provide enum lock_usage_bit mask names Date: Fri, 28 Dec 2018 06:02:01 +0100 Message-Id: <1545973321-24422-3-git-send-email-frederic@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1545973321-24422-1-git-send-email-frederic@kernel.org> References: <1545973321-24422-1-git-send-email-frederic@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Cc: Peter Zijlstra Cc: 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 118a554..115d43e 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 88c847a..2ebb9d0 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: */ -- 2.7.4