From nobody Mon Feb 9 03:50:58 2026 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C7D7035971B; Tue, 3 Feb 2026 06:30:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=114.242.206.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770100245; cv=none; b=lcUvaeOEXdX2lpRiFKS+YnIpUK7I8AE6Xe87SNpEx9Mh2QizbP5Keiesl/rXr4Htytir8Q3M0zDVk9+kg71CY6Ny7C9NzfZyA2TRxW3TRX6v0ZzeVcLTX/xSp5Li98PQESXoGUo/U9ovNQmeFQ4LQQBpGAK6QGlmA1cHzFr8W78= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770100245; c=relaxed/simple; bh=zo2I6k8/xlGq0PtkAsWQuRfNUucflvH2Yo+nLd/eEMw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=QWhuxiv+lfqOKTCvOvEO6CAkL/8zjiWTUKvX4/Ujj2JrMudtfamGuX/VNWUdHFJAOxrIW7ip+c8NERN8h2N9aeLULAMqeZq4ZmnPqAgr2gfG98ArU/HN0FsyBxyFLJNAbGkPUvBB3xxf6TfX5BxmE1826gOMC82RjvRyBBAUp+I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn; spf=pass smtp.mailfrom=loongson.cn; arc=none smtp.client-ip=114.242.206.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [223.64.69.42]) by gateway (Coremail) with SMTP id _____8DxvsMRloFpVkUPAA--.49940S3; Tue, 03 Feb 2026 14:30:41 +0800 (CST) Received: from localhost.localdomain (unknown [223.64.69.42]) by front1 (Coremail) with SMTP id qMiowJCxecEMloFp4e4+AA--.24733S2; Tue, 03 Feb 2026 14:30:40 +0800 (CST) From: Huacai Chen To: Huacai Chen , Alexander Viro , Christian Brauner Cc: Jan Kara , linux-fsdevel@vger.kernel.org, Xuefeng Li , Julian Sun , linux-kernel@vger.kernel.org, Huacai Chen Subject: [PATCH V2] writeback: Fix wakeup and logging timeouts for !DETECT_HUNG_TASK Date: Tue, 3 Feb 2026 14:30:23 +0800 Message-ID: <20260203063023.2159073-1-chenhuacai@loongson.cn> X-Mailer: git-send-email 2.47.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: qMiowJCxecEMloFp4e4+AA--.24733S2 X-CM-SenderInfo: hfkh0x5xdftxo6or00hjvr0hdfq/ X-Coremail-Antispam: 1Uk129KBj93XoW7Kw4xur1fCFWrtF47JF15ZFc_yoW8uw1rpF WfGF1jyayvy34xKr1kG3ZFgF1Y93ykCr4xWr17WayIvw1fXa95tFW7Kry5tF13JrZxXFyS vFWqyrWfJF1jqagCm3ZEXasCq-sJn29KB7ZKAUJUUUUr529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUU9Fb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2kKe7AKxVWUXVWUAwAS0I0E0xvYzxvE52x082IY62kv0487Mc804VCY07 AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU tVWrXwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7V AKI48JMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMxCIbckI1I0E14v2 6r1Y6r17MI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17 CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26ryj6F1UMIIF 0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIx AIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2 KfnxnUUI43ZEXa7IU8EeHDUUUUU== Content-Type: text/plain; charset="utf-8" Recent changes of fs-writeback cause such warnings if DETECT_HUNG_TASK is not enabled: INFO: The task sync:1342 has been waiting for writeback completion for more= than 1 seconds. The reason is sysctl_hung_task_timeout_secs is 0 when DETECT_HUNG_TASK is not enabled, then it causes the warning message even if the writeback lasts for only one second. So guard the wakeup and logging with "#ifdef CONFIG_DETECT_HUNG_TASK", so as to eliminate the warning messages. Fixes: 1888635532fb ("writeback: Wake up waiting tasks when finishing the w= riteback of a chunk.") Fixes: d6e621590764 ("writeback: Add logging for slow writeback (exceeds sy= sctl_hung_task_timeout_secs)") Signed-off-by: Huacai Chen Reviewed-by: Jan Kara --- V2: Disable wakeup and logging for !DETECT_HUNG_TASK. fs/fs-writeback.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 5444fc706ac7..bfe469fff97c 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -198,13 +198,15 @@ static void wb_queue_work(struct bdi_writeback *wb, =20 static bool wb_wait_for_completion_cb(struct wb_completion *done) { +#ifdef CONFIG_DETECT_HUNG_TASK unsigned long waited_secs =3D (jiffies - done->wait_start) / HZ; =20 - done->progress_stamp =3D jiffies; if (waited_secs > sysctl_hung_task_timeout_secs) pr_info("INFO: The task %s:%d has been waiting for writeback " "completion for more than %lu seconds.", current->comm, current->pid, waited_secs); +#endif + done->progress_stamp =3D jiffies; =20 return !atomic_read(&done->cnt); } @@ -2029,11 +2031,13 @@ static long writeback_sb_inodes(struct super_block = *sb, */ __writeback_single_inode(inode, &wbc); =20 +#ifdef CONFIG_DETECT_HUNG_TASK /* Report progress to inform the hung task detector of the progress. */ if (work->done && work->done->progress_stamp && (jiffies - work->done->progress_stamp) > HZ * sysctl_hung_task_timeout_secs / 2) wake_up_all(work->done->waitq); +#endif =20 wbc_detach_inode(&wbc); work->nr_pages -=3D write_chunk - wbc.nr_to_write; --=20 2.47.3