From patchwork Thu Apr 16 13:24:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 227529 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=ham 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 57FCBC2BB55 for ; Thu, 16 Apr 2020 15:55:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 350ED214AF for ; Thu, 16 Apr 2020 15:55:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587052523; bh=CSAq5rROppY5//OEGvd2X8BZ1Ko3UATRHocojnY+lYU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=oGz1F59I8O/D+VkgrYPtVGD9Ps4kVB1gAPzBTBw/R9y+LYkQcn2+njyX7icKg4DyQ BmBl4wLOfUTpAG7potcCkeuDQyLIYbyXeq9uKm22rfrBb3l/3LqQYfm52jpnfERhsK L1eB05HNkpg9m9aiCdJCSZMroZXkmdeTFwYJmRXA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2636156AbgDPPzR (ORCPT ); Thu, 16 Apr 2020 11:55:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:39936 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2896105AbgDPN3x (ORCPT ); Thu, 16 Apr 2020 09:29:53 -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 970E721D94; Thu, 16 Apr 2020 13:29:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587043793; bh=CSAq5rROppY5//OEGvd2X8BZ1Ko3UATRHocojnY+lYU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sGExd6hdJkc8L7/s8FF/iEjWdBF/E+YM4AXfuV4V+sVE2l+yHO7FVxokmiC8IiBnM 2VAmatjKfRCZXOVHU8nr1xvnlrBZlXVEBT+chbz4J4NyuAAP3rysyD9UpQV344s4II cEKBicUxEpNgEWuiqZyaqp2w9z+yUXNYvb6QO64s= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Mike Snitzer Subject: [PATCH 4.19 102/146] dm writecache: add cond_resched to avoid CPU hangs Date: Thu, 16 Apr 2020 15:24:03 +0200 Message-Id: <20200416131256.671279018@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200416131242.353444678@linuxfoundation.org> References: <20200416131242.353444678@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -878,6 +878,7 @@ 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; @@ -932,6 +933,7 @@ 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++) { @@ -1764,8 +1766,10 @@ 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);