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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 113D0CD4F5F for ; Thu, 13 Nov 2025 08:41:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6E6E08E0014; Thu, 13 Nov 2025 03:41:01 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 6BD9F8E0011; Thu, 13 Nov 2025 03:41:01 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5FA708E0014; Thu, 13 Nov 2025 03:41:01 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 4EE328E0011 for ; Thu, 13 Nov 2025 03:41:01 -0500 (EST) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id E644612E5AD for ; Thu, 13 Nov 2025 08:41:00 +0000 (UTC) X-FDA: 84104938680.19.9FEC5BA Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf10.hostedemail.com (Postfix) with ESMTP id 53C3EC0009 for ; Thu, 13 Nov 2025 08:40:59 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=pSAt6uXD; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=lst.de (policy=none); spf=none (imf10.hostedemail.com: domain of BATV+fa6b10aa88fb4b0ddc30+8117+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+fa6b10aa88fb4b0ddc30+8117+infradead.org+hch@bombadil.srs.infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1763023259; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=8Bi/XPLfLPitz3QFgeWKraJXa3JEmVmi80D2Ta/Izrs=; b=ZKA3AVJIQCqVugMWmVas2ERQz/SZ3Orwm80NLx8mcklZakFUjp5tbMaVt9lOZ7ntjQDTot j6JDiPK6xxzu+/jkN3zWt7JK7Yc4Q5VV/NuM5/cMqYauhuVyUCMlQ3gfm4BbLZgps0Y5QX GW8gOxrAEVIE7Fqn/lkTjQK0/0ahIYo= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1763023259; a=rsa-sha256; cv=none; b=Zu5gFsZOtsNFAZj4AE8pKbL1VCxt9/gCjFujYsOy69dUHsAPpYy7ty5g52zuu96hZe0boF 5tdkUlWlXHS7QNNQWHmAKHKbCfQkxdd7ElsxuEURlBFc2fF8CGMEdWKcL0n2RUCt1InwcO u8mPnd6Y0FEA0eqEqdqk22MMyLC1wQU= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=pSAt6uXD; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=lst.de (policy=none); spf=none (imf10.hostedemail.com: domain of BATV+fa6b10aa88fb4b0ddc30+8117+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+fa6b10aa88fb4b0ddc30+8117+infradead.org+hch@bombadil.srs.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=8Bi/XPLfLPitz3QFgeWKraJXa3JEmVmi80D2Ta/Izrs=; b=pSAt6uXDuV54wYKSjed0vjd2l0 Ow3XeFxH55qemFo4LisNTpjDSMqYRHyiKJFN0tN5MPyRtpOtvAaKDhLa3ADkSACzqW3Ydgv9Q2AjE PW1VJGNcFEyFqt5VtNWeFAvNpSsv2QGN2YeWJHptkrncTNGSpHQ7r3jcMpmxXpdUvuYdIfv3De629 H9n8ZM+obWkoXZC4aPnJcZ6jUrxd8M7nsiYkFKV2KIHJbpoT5a/EdO7RniUh18WmuQ/XFIoi+rgXl G2O9CFV41dEGE9WyvbUWFzQRLjSUbSuBegagFiCwXFb9iIZVKOb3KJMUatT97i0UwU3D2TFF7PfRy zHdCSH8A==; Received: from 2a02-8389-2341-5b80-d601-7564-c2e0-491c.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:d601:7564:c2e0:491c] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vJSsx-0000000A7Qj-1Vux; Thu, 13 Nov 2025 08:40:55 +0000 From: Christoph Hellwig To: Vlastimil Babka , Andrew Morton Cc: Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Zi Yan , Eric Biggers , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 04/11] mempool: add error injection support Date: Thu, 13 Nov 2025 09:39:45 +0100 Message-ID: <20251113084022.1255121-5-hch@lst.de> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251113084022.1255121-1-hch@lst.de> References: <20251113084022.1255121-1-hch@lst.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Stat-Signature: bghqecqzc1pdq6g6df35a57ch56eexix X-Rspam-User: X-Rspamd-Queue-Id: 53C3EC0009 X-Rspamd-Server: rspam10 X-HE-Tag: 1763023259-534468 X-HE-Meta: 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 xyc9URMe 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Add a call to should_fail_ex that forces mempool to actually allocate from the pool to stress the mempool implementation when enabled through debugfs. By default should_fail{,_ex} prints a very verbose stack trace that clutters the kernel log, slows down execution and triggers the kernel bug detection in xfstests. Pass FAULT_NOWARN and print a single-line message notating the caller instead so that full tests can be run with fault injection. Signed-off-by: Christoph Hellwig Acked-by: Vlastimil Babka --- mm/mempool.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/mm/mempool.c b/mm/mempool.c index 1f4701713203..5cf59779cc3d 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -9,7 +9,7 @@ * started by Ingo Molnar, Copyright (C) 2001 * debugging by David Rientjes, Copyright (C) 2015 */ - +#include #include #include #include @@ -20,6 +20,15 @@ #include #include "slab.h" +static DECLARE_FAULT_ATTR(fail_mempool_alloc); + +static int __init mempool_faul_inject_init(void) +{ + return PTR_ERR_OR_ZERO(fault_create_debugfs_attr("fail_mempool_alloc", + NULL, &fail_mempool_alloc)); +} +late_initcall(mempool_faul_inject_init); + #ifdef CONFIG_SLUB_DEBUG_ON static void poison_error(mempool_t *pool, void *element, size_t size, size_t byte) @@ -404,9 +413,15 @@ void *mempool_alloc_noprof(mempool_t *pool, gfp_t gfp_mask) gfp_temp = gfp_mask & ~(__GFP_DIRECT_RECLAIM|__GFP_IO); repeat_alloc: + if (should_fail_ex(&fail_mempool_alloc, 1, FAULT_NOWARN)) { + pr_info("forcing mempool usage for %pS\n", + (void *)_RET_IP_); + element = NULL; + } else { + element = pool->alloc(gfp_temp, pool->pool_data); + } - element = pool->alloc(gfp_temp, pool->pool_data); - if (likely(element != NULL)) + if (likely(element)) return element; spin_lock_irqsave(&pool->lock, flags); -- 2.47.3