From patchwork Fri Sep 17 02:56:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 12500867 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 C84D8C433FE for ; Fri, 17 Sep 2021 03:00:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B1A45611CA for ; Fri, 17 Sep 2021 03:00:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243568AbhIQDBa (ORCPT ); Thu, 16 Sep 2021 23:01:30 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:56608 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243240AbhIQDB1 (ORCPT ); Thu, 16 Sep 2021 23:01:27 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 9687D223BD; Fri, 17 Sep 2021 03:00:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1631847604; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+1u7JfJ60ADhg0u9Pcl8n+h1Bz25Z10lXHgfdltE1Jc=; b=09WD61SfjEhN3tce5Wk8dsHcJSb/WzRs0PxztPkg/oLbQ8tSPZsUEzjy6uqwmhzuikCPuq U/HwnCMpj/gmCuZzk7ruhT8FrXhKowH88e6xhNyS5IhdEstIJ/afToqMOTj8wFJrEPQ6Xa cVP2L7nrJ3Ww7J3EnBJIz5piqvJIZY0= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1631847604; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+1u7JfJ60ADhg0u9Pcl8n+h1Bz25Z10lXHgfdltE1Jc=; b=x0CJKsYi96KJP/4iSQP5YmW+cfO6FQgofzJz/NaLv+dviaJqtmgBNoT8ZnNF2BRpgwlvYN cVAEWbD8Oc5hvoAg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 3870F13D0B; Fri, 17 Sep 2021 02:59:59 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id s9QlOq8ERGGiMwAAMHmgww (envelope-from ); Fri, 17 Sep 2021 02:59:59 +0000 Subject: [PATCH 5/6] XFS: remove congestion_wait() loop from kmem_alloc() From: NeilBrown To: Andrew Morton , Theodore Ts'o , Andreas Dilger , "Darrick J. Wong" , Matthew Wilcox , Mel Gorman , Michal Hocko , ". Dave Chinner" , Jonathan Corbet Cc: linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Date: Fri, 17 Sep 2021 12:56:57 +1000 Message-ID: <163184741781.29351.4475236694432020436.stgit@noble.brown> In-Reply-To: <163184698512.29351.4735492251524335974.stgit@noble.brown> References: <163184698512.29351.4735492251524335974.stgit@noble.brown> User-Agent: StGit/0.23 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Documentation commment in gfp.h discourages indefinite retry loops on ENOMEM and says of __GFP_NOFAIL that it is definitely preferable to use the flag rather than opencode endless loop around allocator. So remove the loop, instead specifying __GFP_NOFAIL if KM_MAYFAIL was not given. As we no longer have the opportunity to report a warning after some failures, clear __GFP_NOWARN so that the default warning (rate-limited to 1 ever 10 seconds) will be reported instead. Signed-off-by: NeilBrown --- fs/xfs/kmem.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/fs/xfs/kmem.c b/fs/xfs/kmem.c index 6f49bf39183c..575a58e61391 100644 --- a/fs/xfs/kmem.c +++ b/fs/xfs/kmem.c @@ -11,21 +11,14 @@ void * kmem_alloc(size_t size, xfs_km_flags_t flags) { - int retries = 0; gfp_t lflags = kmem_flags_convert(flags); - void *ptr; trace_kmem_alloc(size, flags, _RET_IP_); - do { - ptr = kmalloc(size, lflags); - if (ptr || (flags & KM_MAYFAIL)) - return ptr; - if (!(++retries % 100)) - xfs_err(NULL, - "%s(%u) possible memory allocation deadlock size %u in %s (mode:0x%x)", - current->comm, current->pid, - (unsigned int)size, __func__, lflags); - congestion_wait(BLK_RW_ASYNC, HZ/50); - } while (1); + if (!(flags & KM_MAYFAIL)) { + lflags |= __GFP_NOFAIL; + lflags &= ~__GFP_NOWARN; + } + + return kmalloc(size, lflags); }