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 2DCA2C4332F for ; Thu, 17 Nov 2022 11:29:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239537AbiKQL3A (ORCPT ); Thu, 17 Nov 2022 06:29:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231911AbiKQL26 (ORCPT ); Thu, 17 Nov 2022 06:28:58 -0500 Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D395242996; Thu, 17 Nov 2022 03:28:55 -0800 (PST) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4NCd355dTcz4f3mH3; Thu, 17 Nov 2022 19:28:49 +0800 (CST) Received: from [10.174.176.73] (unknown [10.174.176.73]) by APP1 (Coremail) with SMTP id cCh0CgAn0a_zGnZjPOSPAg--.8579S3; Thu, 17 Nov 2022 19:28:52 +0800 (CST) Subject: Re: [PATCH v2 4/5] blk-iocost: fix sleeping in atomic context warnning To: Tejun Heo , Yu Kuai Cc: hch@lst.de, josef@toxicpanda.com, axboe@kernel.dk, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yi.zhang@huawei.com, "yukuai (C)" References: <20221104023938.2346986-1-yukuai1@huaweicloud.com> <20221104023938.2346986-5-yukuai1@huaweicloud.com> From: Yu Kuai Message-ID: <3da991c6-21e4-8ed8-ba75-ccb92059f0ae@huaweicloud.com> Date: Thu, 17 Nov 2022 19:28:50 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=gbk; format=flowed Content-Transfer-Encoding: 8bit X-CM-TRANSID: cCh0CgAn0a_zGnZjPOSPAg--.8579S3 X-Coremail-Antispam: 1UD129KBjvdXoW7Jry3WF13Jr47Wr48XFWxCrg_yoWfuFc_CF Wv9r4qq3Z8ZanY9FyUtFWDtrWrA34aqr1xWr48XF98tw1jvw15Ga17Jry0qw45JFWF9F4D CrW5Crsagr47XjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUb3kFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j 6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcVAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kI c2xKxwCYjI0SjxkI62AI1cAE67vIY487MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4 AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE 17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMI IF0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_WFyUJVCq 3wCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r1j6r4UYxBIda VFxhVjvjDU0xZFpf9x0JUdHUDUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Tejun! ÔÚ 2022/11/15 6:07, Tejun Heo дµÀ: > > Any chance I can persuade you into updating match_NUMBER() helpers to not > use match_strdup()? They can easily disable irq/preemption and use percpu > buffers and we won't need most of this patchset. Does the following patch match your proposal? diff --git a/lib/parser.c b/lib/parser.c index bcb23484100e..ded652471919 100644 --- a/lib/parser.c +++ b/lib/parser.c @@ -11,6 +11,24 @@ #include #include +#define U64_MAX_SIZE 20 + +static DEFINE_PER_CPU(char, buffer[U64_MAX_SIZE]); + +static char *get_buffer(void) +{ + preempt_disable(); + local_irq_disable(); + + return this_cpu_ptr(buffer); +} + +static void put_buffer(void) +{ + local_irq_enable(); + preempt_enable(); +} + Then match_strdup() and kfree() in match_NUMBER() can be replaced with get_buffer() and put_buffer(). Thanks, Kuai > > Thanks. >