From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6244C145348; Mon, 6 Jan 2025 15:59:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736179198; cv=none; b=b5Vob956fApNJP81uyN80kDNuATJDLLBUKHRRDD3FQL9Rlj3RhoK6sHXnGATognGBYrkkp65MWJ8r3pVWskHZskyz42dRryrsZHw5b/+y5vT7u/B+KqeSSZ3fZp4Q6uF0OgmLT4MygU4nd9SNcQg32c67PWuZeyHLFf4fAxp9o8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736179198; c=relaxed/simple; bh=vZF1t1TlGho8KnPZkv7thiNuPd+A0kZW8kBRJ5GaF5M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=S58ZpA1EF2jVms7TM09FByW+skW0vfha21rOkCFiN66/As3h/VUjD+q7rr7JXWuyxqTUbCrQ6NTnw9F+dxwHcJrMShclUJFi7+jukj2H4/DkK+jlBPXBp4z4caN3y9MHkXOw7XhfPDazXNHpei8jtQ4vRxYB0L5R5H7vRkefejY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oTqmXrTM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="oTqmXrTM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA37BC4CED2; Mon, 6 Jan 2025 15:59:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1736179198; bh=vZF1t1TlGho8KnPZkv7thiNuPd+A0kZW8kBRJ5GaF5M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oTqmXrTMdPtaGKwTzLwczXUOShDAkUbz6MM+kwrTX1C3QpbbmapAgR512U2DWwd9d paXQT3iPVbNwD8YwD75ZB/CMXfepviSSfx9hZkGVhuGhW4jqTb0yIzIMS/XUH5PTXg B7rQzt3HzywwFNGT7CCL3N62pxrH6I665QM4oG0c= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qu Wenruo , Filipe Manana , David Sterba Subject: [PATCH 5.4 59/93] btrfs: avoid monopolizing a core when activating a swap file Date: Mon, 6 Jan 2025 16:17:35 +0100 Message-ID: <20250106151130.932552278@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250106151128.686130933@linuxfoundation.org> References: <20250106151128.686130933@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Filipe Manana commit 2c8507c63f5498d4ee4af404a8e44ceae4345056 upstream. During swap activation we iterate over the extents of a file and we can have many thousands of them, so we can end up in a busy loop monopolizing a core. Avoid this by doing a voluntary reschedule after processing each extent. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/inode.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7679,6 +7679,8 @@ noinline int can_nocow_extent(struct ino ret = -EAGAIN; goto out; } + + cond_resched(); } btrfs_release_path(path);