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 4F81C2356AB; Mon, 10 Mar 2025 18:14:36 +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=1741630476; cv=none; b=tCvOHs0jousjEckwv1XdxRgBQxCUCIJq7WGIovJxCzCbZ9SaRZf1jwlmoaZQUZrT72XxoDLVRTCrZ2Z5cJ9SsQsnHEB/1u4UETooKZPhKHadb3NVicshpuMRcnAIC+zmxoaTX0cTHsafzi+G++B/Gprh/0ldqkedmJ8tKcPMJM8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741630476; c=relaxed/simple; bh=chstK6hWzyllcsY2Qgph3DDyOVJI7nZnfvxNseeS2lM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Xz28h84MVVXPFV4c4BItKEEdFRy7pJeywzTPlEmBQoaqtugMg8DWyjJqwIrxRYAb5zvUXfgIjbEbYqnAHdNihhft/3jIKxVMnj2VBspl54u8fAnZN91CZFSVq4IXfOAJCh1gPnlNaOdYAPRdxDujwQC0oRwGvFw+ELUpxLbGChA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BMlDn+C9; 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="BMlDn+C9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AEED2C4AF09; Mon, 10 Mar 2025 18:14:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741630476; bh=chstK6hWzyllcsY2Qgph3DDyOVJI7nZnfvxNseeS2lM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BMlDn+C9dAs7MPoBxRxCtKzqixSqbAOoVnlVz/rxkC9jb3rz/DhPpwnmu7SjNlYlm BBDfaA2sn0M+I8vmUJ0wvGDL/PCgAFpK5auH12vVig5dUn+XMpgDsquXabjaiTGkwg 3Skk8JMvaa8VpYEovw0ti1ne9gjgNsFrll/bkd2w= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qu Wenruo , Filipe Manana , David Sterba , Koichiro Den Subject: [PATCH 5.15 428/620] btrfs: avoid monopolizing a core when activating a swap file Date: Mon, 10 Mar 2025 18:04:34 +0100 Message-ID: <20250310170602.491778053@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250310170545.553361750@linuxfoundation.org> References: <20250310170545.553361750@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Filipe Manana commit 2c8507c63f5498d4ee4af404a8e44ceae4345056 upstream. This commit re-attempts the backport of the change to the linux-5.15.y branch. Commit 214d92f0a465 ("btrfs: avoid monopolizing a core when activating a swap file") on this branch was reverted. 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: Koichiro Den 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 @@ -11031,6 +11031,8 @@ static int btrfs_swap_activate(struct sw } start += len; + + cond_resched(); } if (bsi.block_len)