From nobody Wed Feb 11 02:08:52 2026 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 E8A68C76196 for ; Sun, 2 Apr 2023 09:13:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230318AbjDBJNW (ORCPT ); Sun, 2 Apr 2023 05:13:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36276 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230295AbjDBJNL (ORCPT ); Sun, 2 Apr 2023 05:13:11 -0400 Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 78BAACC36; Sun, 2 Apr 2023 02:13:08 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4Pq7bg22Y6z4f3lKM; Sun, 2 Apr 2023 17:13:03 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgD3X7MeRylkVUE8Gg--.50168S7; Sun, 02 Apr 2023 17:13:05 +0800 (CST) From: Yu Kuai To: logang@deltatee.com, song@kernel.org Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH v4 3/5] md: add a helper to access md_thread() directly Date: Sun, 2 Apr 2023 17:12:34 +0800 Message-Id: <20230402091236.976723-4-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230402091236.976723-1-yukuai1@huaweicloud.com> References: <20230402091236.976723-1-yukuai1@huaweicloud.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgD3X7MeRylkVUE8Gg--.50168S7 X-Coremail-Antispam: 1UD129KBjvJXoWxuFy5tw18ZFWrWry5Jr4ktFb_yoWrCFy8pa yvqFyY9w48AFW3Zr1DAaykuFyFqwn2gF9rKryfC3yrC3W5G398Jry5CFyjyr1DZF1FyF43 tF15Kr48GF4vgr7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9v14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JrWl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxAIw28IcxkI7VAKI48JMxC20s 026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_ JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14 v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xva j40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JV W8JrUvcSsGvfC2KfnxnUUI43ZEXa7VUbJ73DUUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Yu Kuai In some context it's safe to access md_thread directly without protection, this patch add a helper to do that. There are no functional changes, prepare to protect md_thread with rcu. Signed-off-by: Yu Kuai --- drivers/md/md-bitmap.c | 7 ++++--- drivers/md/md.c | 4 +++- drivers/md/md.h | 6 ++++++ drivers/md/raid10.c | 2 +- drivers/md/raid5-cache.c | 7 ++++--- 5 files changed, 18 insertions(+), 8 deletions(-) diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c index e7cc6ba1b657..f670c72d97be 100644 --- a/drivers/md/md-bitmap.c +++ b/drivers/md/md-bitmap.c @@ -1246,7 +1246,7 @@ void md_bitmap_daemon_work(struct mddev *mddev) =20 bitmap->daemon_lastrun =3D jiffies; if (bitmap->allclean) { - mddev->thread->timeout =3D MAX_SCHEDULE_TIMEOUT; + get_md_thread(mddev->thread)->timeout =3D MAX_SCHEDULE_TIMEOUT; goto done; } bitmap->allclean =3D 1; @@ -1343,7 +1343,7 @@ void md_bitmap_daemon_work(struct mddev *mddev) =20 done: if (bitmap->allclean =3D=3D 0) - mddev->thread->timeout =3D + get_md_thread(mddev->thread)->timeout =3D mddev->bitmap_info.daemon_sleep; mutex_unlock(&mddev->bitmap_info.mutex); } @@ -1941,7 +1941,8 @@ int md_bitmap_load(struct mddev *mddev) /* Kick recovery in case any bits were set */ set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery); =20 - mddev->thread->timeout =3D mddev->bitmap_info.daemon_sleep; + get_md_thread(mddev->thread)->timeout =3D + mddev->bitmap_info.daemon_sleep; md_wakeup_thread(mddev->thread); =20 md_bitmap_update_sb(bitmap); diff --git a/drivers/md/md.c b/drivers/md/md.c index 139c7b0202e3..d5a29ccb24ec 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -458,7 +458,9 @@ static void md_submit_bio(struct bio *bio) */ void mddev_suspend(struct mddev *mddev) { - WARN_ON_ONCE(mddev->thread && current =3D=3D mddev->thread->tsk); + struct md_thread *thread =3D get_md_thread(mddev->thread); + + WARN_ON_ONCE(thread && current =3D=3D thread->tsk); lockdep_assert_held(&mddev->reconfig_mutex); if (mddev->suspended++) return; diff --git a/drivers/md/md.h b/drivers/md/md.h index 344e055e4d0f..5acdd704a922 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -718,6 +718,12 @@ struct md_io_acct { =20 #define THREAD_WAKEUP 0 =20 +/* caller need to make sured returned md_thread won't be freed */ +static inline struct md_thread *get_md_thread(struct md_thread *t) +{ + return t; +} + static inline void safe_put_page(struct page *p) { if (p) put_page(p); diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 0171ba4f19b0..fc8d07fb1c7d 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -996,7 +996,7 @@ static bool stop_waiting_barrier(struct r10conf *conf) return true; =20 /* move on if recovery thread is blocked by us */ - if (conf->mddev->thread->tsk =3D=3D current && + if (get_md_thread(conf->mddev->thread)->tsk =3D=3D current && test_bit(MD_RECOVERY_RUNNING, &conf->mddev->recovery) && conf->nr_queued > 0) return true; diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index 0464d4d551fc..7e45df3e093f 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -1582,11 +1582,11 @@ void r5l_quiesce(struct r5l_log *log, int quiesce) /* make sure r5l_write_super_and_discard_space exits */ mddev =3D log->rdev->mddev; wake_up(&mddev->sb_wait); - kthread_park(log->reclaim_thread->tsk); + kthread_park(get_md_thread(log->reclaim_thread)->tsk); r5l_wake_reclaim(log, MaxSector); r5l_do_reclaim(log); } else - kthread_unpark(log->reclaim_thread->tsk); + kthread_unpark(get_md_thread(log->reclaim_thread)->tsk); } =20 bool r5l_log_disk_error(struct r5conf *conf) @@ -3124,7 +3124,8 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev = *rdev) if (md_register_thread(&log->reclaim_thread, r5l_reclaim_thread, log->rdev->mddev, "reclaim")) goto reclaim_thread; - log->reclaim_thread->timeout =3D R5C_RECLAIM_WAKEUP_INTERVAL; + get_md_thread(log->reclaim_thread)->timeout =3D + R5C_RECLAIM_WAKEUP_INTERVAL; =20 init_waitqueue_head(&log->iounit_wait); =20 --=20 2.39.2