From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-402196-1526281275-2-15608630891594077591 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, MAILING_LIST_MULTI -1, RCVD_IN_DNSWL_HI -5, LANGUAGES sk.us-asciienro, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=fm2; t= 1526281274; b=XUnp+uAy+ZSE8BIoTVy+RsU6O+lys1hTOPEcfMJc9fYA/0+edo ANrCGSjvS6/pw1n0LGHeoaatSXwx66S7YIU4WAi9Nx7J+mCBC20JY8FfzGALfiiI nEdSJQ0BKycabBpKQabH7osQ36dfSI+wCA+4NCXj3HTenq3mSsao9QpgXNmP9Wm5 t+Uvikw4YAVqOzI9HZ278A3+SecmDaU9ClOjdrho8aMkpnrpMyziy3Pkc85PKG9l xqUCPM4qJ10mUM+QH0nzU1c8PhEcQLEAp8oYZNKg5fZszCu0XeQqdMpzp7Wdui0y 5VYSiRqLb/BN03EmdnpwySSA7e7M5unTS+SA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=fm2; t=1526281274; bh=oqAeyXRDxEANN8nucxLUoYAdCJPxtm wtMJ+vSiSOK5o=; b=BwvwltuufWV7qR5J6m8LktLyOrD0Z89jYWUIXEeWQi7rcH md5/3djWH31giiLjdz31aRVK8BnYXRYSn+qkr/iJlbp7mLSkKd48entG3WNQ5MBp B5Av9hS7purx22WXwFA4VeI0+gnG+bUbEC6K4K+QHvFSbwZlL9qVHyRPKmwJtAGo 5GrUpTGXanceRjAYDQU7cE0wdXRmYYEC2JZ/9H7qaeel4EnajpeGW9k8hCrhT7/D YrJpyP30NA3Mf91SxpqL3k6jQnhZvFaK01jP1cXRt3SO3+/RVIfslvYtpYeAnrcL Z3hwfTawJ4kuqJ4ZxMAp9AbjVkpkozUQnfeNjTMQ== ARC-Authentication-Results: i=1; mx4.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=kernel.org header.i=@kernel.org header.b=EmZmfCrB x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=default; dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx4.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=kernel.org header.i=@kernel.org header.b=EmZmfCrB x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=default; dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfP9rWiiicxVajhucpJJ3lqXXnQolIrb3d+2f19xrbwl3fBopPeFUu2D+H54DpTKsfmKD2XDyJsaHC4fvzvUeK+tiUgjFDrIeGKTIB5g85QYPayD0XiUR g1SBG8CbmbmNlMq6DkgNsa9YR5nNB40jHA2qzrM81y8xVEZVibt20k9Ouz2Zqo99NsLUCs8nV2I9d6XK8cZvSN7hvc29bo5tbuk2JmByZK7cWybA633uNl2K X-CM-Analysis: v=2.3 cv=JLoVTfCb c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=IkcTkHD0fZMA:10 a=VUJBJC2UJ8kA:10 a=pGLkceISAAAA:8 a=Z4Rwk6OoAAAA:8 a=VwQbUJbxAAAA:8 a=z6gsHLkEAAAA:8 a=_jlGtV7tAAAA:8 a=yMhMjlubAAAA:8 a=ag1SF4gXAAAA:8 a=0K4TOLIue6-ewoCfQ-cA:9 a=QEXdDO2ut3YA:10 a=HkZW87K1Qel5hWWM3VKY:22 a=AjGcO6oz07-iQ99wixmX:22 a=d-OLMTCWyvARjPbQ-enb:22 a=nlm17XC03S6CtCLSeiRr:22 a=Yupwre4RP9_Eg_Bd0iYG:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754231AbeENHA7 (ORCPT ); Mon, 14 May 2018 03:00:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:37760 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754173AbeENHA4 (ORCPT ); Mon, 14 May 2018 03:00:56 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Wool , Guenter Roeck , Oleksiy.Avramchenko@sony.com, Matthew Wilcox , Andrew Morton , Linus Torvalds Subject: [PATCH 4.16 31/72] z3fold: fix reclaim lock-ups Date: Mon, 14 May 2018 08:48:48 +0200 Message-Id: <20180514064824.416301035@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180514064823.033169170@linuxfoundation.org> References: <20180514064823.033169170@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vitaly Wool commit 6098d7e136692f9c6e23ae362c62ec822343e4d5 upstream. Do not try to optimize in-page object layout while the page is under reclaim. This fixes lock-ups on reclaim and improves reclaim performance at the same time. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20180430125800.444cae9706489f412ad12621@gmail.com Signed-off-by: Vitaly Wool Reported-by: Guenter Roeck Tested-by: Guenter Roeck Cc: Cc: Matthew Wilcox Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/z3fold.c | 42 ++++++++++++++++++++++++++++++------------ 1 file changed, 30 insertions(+), 12 deletions(-) --- a/mm/z3fold.c +++ b/mm/z3fold.c @@ -144,7 +144,8 @@ enum z3fold_page_flags { PAGE_HEADLESS = 0, MIDDLE_CHUNK_MAPPED, NEEDS_COMPACTING, - PAGE_STALE + PAGE_STALE, + UNDER_RECLAIM }; /***************** @@ -173,6 +174,7 @@ static struct z3fold_header *init_z3fold clear_bit(MIDDLE_CHUNK_MAPPED, &page->private); clear_bit(NEEDS_COMPACTING, &page->private); clear_bit(PAGE_STALE, &page->private); + clear_bit(UNDER_RECLAIM, &page->private); spin_lock_init(&zhdr->page_lock); kref_init(&zhdr->refcount); @@ -748,6 +750,10 @@ static void z3fold_free(struct z3fold_po atomic64_dec(&pool->pages_nr); return; } + if (test_bit(UNDER_RECLAIM, &page->private)) { + z3fold_page_unlock(zhdr); + return; + } if (test_and_set_bit(NEEDS_COMPACTING, &page->private)) { z3fold_page_unlock(zhdr); return; @@ -832,6 +838,8 @@ static int z3fold_reclaim_page(struct z3 kref_get(&zhdr->refcount); list_del_init(&zhdr->buddy); zhdr->cpu = -1; + set_bit(UNDER_RECLAIM, &page->private); + break; } list_del_init(&page->lru); @@ -879,25 +887,35 @@ static int z3fold_reclaim_page(struct z3 goto next; } next: - spin_lock(&pool->lock); if (test_bit(PAGE_HEADLESS, &page->private)) { if (ret == 0) { - spin_unlock(&pool->lock); free_z3fold_page(page); return 0; } - } else if (kref_put(&zhdr->refcount, release_z3fold_page)) { - atomic64_dec(&pool->pages_nr); + spin_lock(&pool->lock); + list_add(&page->lru, &pool->lru); + spin_unlock(&pool->lock); + } else { + z3fold_page_lock(zhdr); + clear_bit(UNDER_RECLAIM, &page->private); + if (kref_put(&zhdr->refcount, + release_z3fold_page_locked)) { + atomic64_dec(&pool->pages_nr); + return 0; + } + /* + * if we are here, the page is still not completely + * free. Take the global pool lock then to be able + * to add it back to the lru list + */ + spin_lock(&pool->lock); + list_add(&page->lru, &pool->lru); spin_unlock(&pool->lock); - return 0; + z3fold_page_unlock(zhdr); } - /* - * Add to the beginning of LRU. - * Pool lock has to be kept here to ensure the page has - * not already been released - */ - list_add(&page->lru, &pool->lru); + /* We started off locked to we need to lock the pool back */ + spin_lock(&pool->lock); } spin_unlock(&pool->lock); return -EAGAIN;