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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50F49C2BB55 for ; Thu, 16 Apr 2020 14:13:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3072D206D6 for ; Thu, 16 Apr 2020 14:13:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587046414; bh=Q6Ia7usDOLuZ4bedNUL50Ce4q2NYsM6H3bmyAwXYQEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wPgA0M4sJeSvPAY8pe3zBZ3Jr68SZSsFHIF3cCuGD+wmbRbYjB2XDbbKVrT1zgz2q qO4gr/RKbdN5G/PP1LRoWc+rIN9ywlWswQmt9dNPkG8dm5thOwtrr3s4vhLhZV7NRc UTIvPyX/cC7IN99g11/jMtYgOpcnv8jOtKCNncs0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2441950AbgDPONc (ORCPT ); Thu, 16 Apr 2020 10:13:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:34882 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2898782AbgDPNs5 (ORCPT ); Thu, 16 Apr 2020 09:48:57 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id ADF2E20732; Thu, 16 Apr 2020 13:48:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587044936; bh=Q6Ia7usDOLuZ4bedNUL50Ce4q2NYsM6H3bmyAwXYQEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qKd51s+cnU6BNNvHfSlszHsj9tS93HSLQ8hJG6La/AqG5cpyb9dhLen2iuB8+OjVv WwqUPwLZ+R8QLAaisUN9UfGhowWcJo189+p+0Jx8UDruzddbMBoIleUKpPUlW2agbW +ka005hhL1jJxFNStbpfFhjFgKakFZcOfVKkMD9c= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Mike Snitzer Subject: [PATCH 5.4 161/232] dm writecache: add cond_resched to avoid CPU hangs Date: Thu, 16 Apr 2020 15:24:15 +0200 Message-Id: <20200416131335.128511666@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200416131316.640996080@linuxfoundation.org> References: <20200416131316.640996080@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikulas Patocka commit 1edaa447d958bec24c6a79685a5790d98976fd16 upstream. Initializing a dm-writecache device can take a long time when the persistent memory device is large. Add cond_resched() to a few loops to avoid warnings that the CPU is stuck. Cc: stable@vger.kernel.org # v4.18+ Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-writecache.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -872,6 +872,7 @@ static int writecache_alloc_entries(stru struct wc_entry *e = &wc->entries[b]; e->index = b; e->write_in_progress = false; + cond_resched(); } return 0; @@ -926,6 +927,7 @@ static void writecache_resume(struct dm_ e->original_sector = le64_to_cpu(wme.original_sector); e->seq_count = le64_to_cpu(wme.seq_count); } + cond_resched(); } #endif for (b = 0; b < wc->n_blocks; b++) { @@ -1770,8 +1772,10 @@ static int init_memory(struct dm_writeca pmem_assign(sb(wc)->n_blocks, cpu_to_le64(wc->n_blocks)); pmem_assign(sb(wc)->seq_count, cpu_to_le64(0)); - for (b = 0; b < wc->n_blocks; b++) + for (b = 0; b < wc->n_blocks; b++) { write_original_sector_seq_count(wc, &wc->entries[b], -1, -1); + cond_resched(); + } writecache_flush_all_metadata(wc); writecache_commit_flushed(wc, false);