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 EFBC0C433F5 for ; Mon, 18 Apr 2022 15:14:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239800AbiDRPRL (ORCPT ); Mon, 18 Apr 2022 11:17:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242390AbiDRPPm (ORCPT ); Mon, 18 Apr 2022 11:15:42 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C212BB9186 for ; Mon, 18 Apr 2022 07:12:30 -0700 (PDT) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4KhpjM4t6MzFplq; Mon, 18 Apr 2022 22:09:59 +0800 (CST) Received: from huawei.com (10.175.124.27) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 18 Apr 2022 22:12:28 +0800 From: Miaohe Lin To: CC: , , , , , Subject: [PATCH 04/12] mm: compaction: clean up comment for sched contention Date: Mon, 18 Apr 2022 22:12:45 +0800 Message-ID: <20220418141253.24298-5-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220418141253.24298-1-linmiaohe@huawei.com> References: <20220418141253.24298-1-linmiaohe@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since commit cf66f0700c8f ("mm, compaction: do not consider a need to reschedule as contention"), async compaction won't abort when scheduling is needed. Correct the relevant comment accordingly. Signed-off-by: Miaohe Lin --- mm/compaction.c | 11 ++++------- mm/internal.h | 2 +- 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c index ee2ddf77191f..e839b26fb3d8 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -513,15 +513,12 @@ static bool compact_lock_irqsave(spinlock_t *lock, unsigned long *flags, * very heavily contended. The lock should be periodically unlocked to avoid * having disabled IRQs for a long time, even when there is nobody waiting on * the lock. It might also be that allowing the IRQs will result in - * need_resched() becoming true. If scheduling is needed, async compaction - * aborts. Sync compaction schedules. + * need_resched() becoming true. If scheduling is needed, compaction schedules. * Either compaction type will also abort if a fatal signal is pending. * In either case if the lock was locked, it is dropped and not regained. * - * Returns true if compaction should abort due to fatal signal pending, or - * async compaction due to need_resched() - * Returns false when compaction can continue (sync compaction might have - * scheduled) + * Returns true if compaction should abort due to fatal signal pending. + * Returns false when compaction can continue. */ static bool compact_unlock_should_abort(spinlock_t *lock, unsigned long flags, bool *locked, struct compact_control *cc) @@ -574,7 +571,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, /* * Periodically drop the lock (if held) regardless of its * contention, to give chance to IRQs. Abort if fatal signal - * pending or async compaction detects need_resched() + * pending. */ if (!(blockpfn % SWAP_CLUSTER_MAX) && compact_unlock_should_abort(&cc->zone->lock, flags, diff --git a/mm/internal.h b/mm/internal.h index 48eb2d24fcd2..70cc61af06de 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -403,7 +403,7 @@ struct compact_control { bool direct_compaction; /* False from kcompactd or /proc/... */ bool proactive_compaction; /* kcompactd proactive compaction */ bool whole_zone; /* Whole zone should/has been scanned */ - bool contended; /* Signal lock or sched contention */ + bool contended; /* Signal lock contention */ bool rescan; /* Rescanning the same pageblock */ bool alloc_contig; /* alloc_contig_range allocation */ }; -- 2.23.0