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 EFE67C433EF for ; Fri, 18 Mar 2022 08:10:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233606AbiCRIL3 (ORCPT ); Fri, 18 Mar 2022 04:11:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33330 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233551AbiCRILT (ORCPT ); Fri, 18 Mar 2022 04:11:19 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16C2F25719F; Fri, 18 Mar 2022 01:10:00 -0700 (PDT) Received: from kwepemi100003.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4KKc8Y35xqzfYnN; Fri, 18 Mar 2022 16:08:29 +0800 (CST) Received: from kwepemm600009.china.huawei.com (7.193.23.164) by kwepemi100003.china.huawei.com (7.221.188.122) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Fri, 18 Mar 2022 16:09:58 +0800 Received: from huawei.com (10.175.127.227) by kwepemm600009.china.huawei.com (7.193.23.164) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Fri, 18 Mar 2022 16:09:58 +0800 From: Yu Kuai To: , , , , , CC: , , Subject: [PATCH RFC -next 1/3] sbitmap: record the number of waiters for each waitqueue Date: Fri, 18 Mar 2022 16:25:03 +0800 Message-ID: <20220318082505.3025427-2-yukuai3@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220318082505.3025427-1-yukuai3@huawei.com> References: <20220318082505.3025427-1-yukuai3@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemm600009.china.huawei.com (7.193.23.164) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is just a helper to provide a api to see if waitqueues are balanced. Signed-off-by: Yu Kuai --- include/linux/sbitmap.h | 5 +++++ lib/sbitmap.c | 7 +++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index dffeb8281c2d..18c68e7f5362 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -91,6 +91,11 @@ struct sbq_wait_state { */ atomic_t wait_cnt; + /** + * @waiters_cnt: Number of active waiters + */ + atomic_t waiters_cnt; + /** * @wait: Wait queue. */ diff --git a/lib/sbitmap.c b/lib/sbitmap.c index 2eb3de18ded3..bde0783e4ace 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -444,6 +444,7 @@ int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth, for (i = 0; i < SBQ_WAIT_QUEUES; i++) { init_waitqueue_head(&sbq->ws[i].wait); atomic_set(&sbq->ws[i].wait_cnt, sbq->wake_batch); + atomic_set(&sbq->ws[i].waiters_cnt, 0); } return 0; @@ -759,9 +760,9 @@ void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m) for (i = 0; i < SBQ_WAIT_QUEUES; i++) { struct sbq_wait_state *ws = &sbq->ws[i]; - seq_printf(m, "\t{.wait_cnt=%d, .wait=%s},\n", + seq_printf(m, "\t{.wait_cnt=%d, .waiters_cnt=%d},\n", atomic_read(&ws->wait_cnt), - waitqueue_active(&ws->wait) ? "active" : "inactive"); + atomic_read(&ws->waiters_cnt)); } seq_puts(m, "}\n"); @@ -798,6 +799,7 @@ void sbitmap_prepare_to_wait(struct sbitmap_queue *sbq, { if (!sbq_wait->sbq) { atomic_inc(&sbq->ws_active); + atomic_inc(&ws->waiters_cnt); sbq_wait->sbq = sbq; } prepare_to_wait_exclusive(&ws->wait, &sbq_wait->wait, state); @@ -810,6 +812,7 @@ void sbitmap_finish_wait(struct sbitmap_queue *sbq, struct sbq_wait_state *ws, finish_wait(&ws->wait, &sbq_wait->wait); if (sbq_wait->sbq) { atomic_dec(&sbq->ws_active); + atomic_dec(&ws->waiters_cnt); sbq_wait->sbq = NULL; } } -- 2.31.1