From patchwork Wed Sep 26 19:13:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nadav Amit X-Patchwork-Id: 10616567 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C35C8174A for ; Wed, 26 Sep 2018 19:15:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B47632A38E for ; Wed, 26 Sep 2018 19:15:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A84D72A39C; Wed, 26 Sep 2018 19:15:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3AC772A3BB for ; Wed, 26 Sep 2018 19:15:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 750D48E0005; Wed, 26 Sep 2018 15:15:12 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 544F98E0004; Wed, 26 Sep 2018 15:15:12 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 396F78E0005; Wed, 26 Sep 2018 15:15:12 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-pf1-f200.google.com (mail-pf1-f200.google.com [209.85.210.200]) by kanga.kvack.org (Postfix) with ESMTP id D0DBC8E0004 for ; Wed, 26 Sep 2018 15:15:11 -0400 (EDT) Received: by mail-pf1-f200.google.com with SMTP id c8-v6so85580pfn.2 for ; Wed, 26 Sep 2018 12:15:11 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:from:to:cc :subject:date:message-id:in-reply-to:references:mime-version; bh=Ox5uPeCneET61SfHC85zHaITGI5GJMznmFvV9SsV9a0=; b=c65PMlDohDyYhzki2+nLtOOuJZQdUh9WAbJKqsXr0zEuGP/rc+cLXSVAbZ1HViwTGC 9L8B/fonn/MCOFaA3SpGhOq/e5ema7W8GlBs+tPVsTk1iGDugNjkZT7x+Voa9REJThOm X7o9c9XQhtga3kQpfbN+3GOJF1QHlS8Mdv2xAzmA/FbehjtrPKthofhVyqFcIlridTsn 8dXZPxBsIU7FwfYgW2VWUZg9o+Zq431cJ7pxkQrOm/hoCGrFajR8FdfAaeC3P3Ax2X37 g0iB28KtOQC5U3+SNvZWEKHp1QW90DCR8lyvhmsYDZzmQuwJlJlElGxYMfs9xEhljkXE 0Hwg== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of namit@vmware.com designates 208.91.0.190 as permitted sender) smtp.mailfrom=namit@vmware.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=vmware.com X-Gm-Message-State: ABuFfoj/0kCSPrJGStvLMm86uVtlbaeDSbTb8V47kpm6qMi46z8kKMQd bLtVHfTbPBsjzAsACgYB78oaICF8srkpjpEvskh0SH4YNRk5ReWbKsRJCeF3aZ2VX6yt1t4htBI b4xxD81zXimJAi8T0j9cESfmS19PW+qzzNYKQTUum6lI2y5TTbfRcqP658dgyJAmZ2g== X-Received: by 2002:a63:4443:: with SMTP id t3-v6mr6937910pgk.102.1537989311539; Wed, 26 Sep 2018 12:15:11 -0700 (PDT) X-Google-Smtp-Source: ACcGV62IrhFjBYBkFmcEfif4UJfe/1SoSzdQ8rGjMIA1lmD2kDmOWX0R0Nq9WR0JfTue0W7Xknkd X-Received: by 2002:a63:4443:: with SMTP id t3-v6mr6937861pgk.102.1537989310722; Wed, 26 Sep 2018 12:15:10 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1537989310; cv=none; d=google.com; s=arc-20160816; b=RgvklnSuTAZW6XxgTLx7TY9sJ7pJKYWU7a4T+OeKbNc6AQ96qCZ22jAI+V4B3LeJah hqNp/xxJTcqNC1EPA945bkOZvgZG1YO/q9rfTcj29/rZYBoGEgU5osj+PjfJAcHsKiWU ebqPK1D+14dlqj6rrK/DcxjcmntPVTjRkH8tBoxOjtzfXlL3M0wERcNl3u9Xx2xIFuKz tieiSvkPB/v+oebnOTOMAcIz3nM4ub0E2LH63qnvykEZSMGu/QxrFoUow0hQSlMC4J6E SJgPvneCddB+H7DAyuw5CDumm7ba0UBRSSkr3tezk18H1AhqRn3twPNLSbd41LpF2tFt dxhg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:references:in-reply-to:message-id:date:subject:cc:to :from; bh=Ox5uPeCneET61SfHC85zHaITGI5GJMznmFvV9SsV9a0=; b=meX8O6QuouJ7RgdRVNrGb7Gmfbtw50gJkR5u5HbS3Vn8nrzcWD2KKy3LZkFbAIKDzD HHbYZvc2T3Bsmij4rOKAgbJq2VvrTgTfibVCsi+TjNG9I764fzGNKv2E63BJJ6ujFcBi 4o/WlnTT7TC0e48Wi/aIVhrqIhmFuJbgmJEzxX8YGkwcOSsMRKyaCPECbOPrmEaDMvvj 5EFZ5hAgmY7krtPMPLQnq+HMpqwZKGTff9u1ts4KW/vavowUzeovjWda9lM4kRyg+Iko BKB5yimBHleog8lPeFNcGUQSPmUpk6CTmtJXWfz6YEFvtZUHIU+a8dMGqXBP2R3zj8l+ 5Cyg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of namit@vmware.com designates 208.91.0.190 as permitted sender) smtp.mailfrom=namit@vmware.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=vmware.com Received: from EX13-EDG-OU-002.vmware.com (ex13-edg-ou-002.vmware.com. [208.91.0.190]) by mx.google.com with ESMTPS id q90-v6si5539344pfa.272.2018.09.26.12.15.10 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 26 Sep 2018 12:15:10 -0700 (PDT) Received-SPF: pass (google.com: domain of namit@vmware.com designates 208.91.0.190 as permitted sender) client-ip=208.91.0.190; Authentication-Results: mx.google.com; spf=pass (google.com: domain of namit@vmware.com designates 208.91.0.190 as permitted sender) smtp.mailfrom=namit@vmware.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=vmware.com Received: from sc9-mailhost2.vmware.com (10.113.161.72) by EX13-EDG-OU-002.vmware.com (10.113.208.156) with Microsoft SMTP Server id 15.0.1156.6; Wed, 26 Sep 2018 12:15:05 -0700 Received: from sc2-haas01-esx0118.eng.vmware.com (sc2-haas01-esx0118.eng.vmware.com [10.172.44.118]) by sc9-mailhost2.vmware.com (Postfix) with ESMTP id E3FCFB0E8E; Wed, 26 Sep 2018 15:15:09 -0400 (EDT) From: Nadav Amit To: Arnd Bergmann , CC: Xavier Deguillard , , Nadav Amit , "Michael S. Tsirkin" , Jason Wang , , Subject: [PATCH v3 15/20] mm/balloon_compaction: suppress allocation warnings Date: Wed, 26 Sep 2018 12:13:31 -0700 Message-ID: <20180926191336.101885-16-namit@vmware.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180926191336.101885-1-namit@vmware.com> References: <20180926191336.101885-1-namit@vmware.com> MIME-Version: 1.0 Received-SPF: None (EX13-EDG-OU-002.vmware.com: namit@vmware.com does not designate permitted sender hosts) 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: X-Virus-Scanned: ClamAV using ClamSMTP There is no reason to print warnings when balloon page allocation fails. Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: virtualization@lists.linux-foundation.org Cc: linux-mm@kvack.org Reviewed-by: Xavier Deguillard Signed-off-by: Nadav Amit --- mm/balloon_compaction.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index ef858d547e2d..a6c0efb3544f 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -22,7 +22,8 @@ struct page *balloon_page_alloc(void) { struct page *page = alloc_page(balloon_mapping_gfp_mask() | - __GFP_NOMEMALLOC | __GFP_NORETRY); + __GFP_NOMEMALLOC | __GFP_NORETRY | + __GFP_NOWARN); return page; } EXPORT_SYMBOL_GPL(balloon_page_alloc); From patchwork Wed Sep 26 19:13:32 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nadav Amit X-Patchwork-Id: 10616565 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1A2E4174A for ; 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[208.91.0.190]) by mx.google.com with ESMTPS id q90-v6si5539344pfa.272.2018.09.26.12.15.10 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 26 Sep 2018 12:15:10 -0700 (PDT) Received-SPF: pass (google.com: domain of namit@vmware.com designates 208.91.0.190 as permitted sender) client-ip=208.91.0.190; Authentication-Results: mx.google.com; spf=pass (google.com: domain of namit@vmware.com designates 208.91.0.190 as permitted sender) smtp.mailfrom=namit@vmware.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=vmware.com Received: from sc9-mailhost2.vmware.com (10.113.161.72) by EX13-EDG-OU-002.vmware.com (10.113.208.156) with Microsoft SMTP Server id 15.0.1156.6; Wed, 26 Sep 2018 12:15:05 -0700 Received: from sc2-haas01-esx0118.eng.vmware.com (sc2-haas01-esx0118.eng.vmware.com [10.172.44.118]) by sc9-mailhost2.vmware.com (Postfix) with ESMTP id F3DFFB0E7B; Wed, 26 Sep 2018 15:15:09 -0400 (EDT) From: Nadav Amit To: Arnd Bergmann , CC: Xavier Deguillard , , Nadav Amit , "Michael S. Tsirkin" , Jason Wang , , Subject: [PATCH v3 16/20] mm/balloon_compaction: list interfaces Date: Wed, 26 Sep 2018 12:13:32 -0700 Message-ID: <20180926191336.101885-17-namit@vmware.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180926191336.101885-1-namit@vmware.com> References: <20180926191336.101885-1-namit@vmware.com> MIME-Version: 1.0 Received-SPF: None (EX13-EDG-OU-002.vmware.com: namit@vmware.com does not designate permitted sender hosts) 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: X-Virus-Scanned: ClamAV using ClamSMTP Introduce interfaces for ballooning enqueueing and dequeueing of a list of pages. These interfaces reduce the overhead of storing and restoring IRQs by batching the operations. In addition they do not panic if the list of pages is empty. Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: linux-mm@kvack.org Cc: virtualization@lists.linux-foundation.org Reviewed-by: Xavier Deguillard Signed-off-by: Nadav Amit --- include/linux/balloon_compaction.h | 4 + mm/balloon_compaction.c | 139 +++++++++++++++++++++-------- 2 files changed, 105 insertions(+), 38 deletions(-) diff --git a/include/linux/balloon_compaction.h b/include/linux/balloon_compaction.h index 53051f3d8f25..2c5a8e09e413 100644 --- a/include/linux/balloon_compaction.h +++ b/include/linux/balloon_compaction.h @@ -72,6 +72,10 @@ extern struct page *balloon_page_alloc(void); extern void balloon_page_enqueue(struct balloon_dev_info *b_dev_info, struct page *page); extern struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info); +extern void balloon_page_list_enqueue(struct balloon_dev_info *b_dev_info, + struct list_head *pages); +extern int balloon_page_list_dequeue(struct balloon_dev_info *b_dev_info, + struct list_head *pages, int n_req_pages); static inline void balloon_devinfo_init(struct balloon_dev_info *balloon) { diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index a6c0efb3544f..b920c2a10d6f 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -10,6 +10,100 @@ #include #include +static int balloon_page_enqueue_one(struct balloon_dev_info *b_dev_info, + struct page *page) +{ + /* + * Block others from accessing the 'page' when we get around to + * establishing additional references. We should be the only one + * holding a reference to the 'page' at this point. + */ + if (!trylock_page(page)) { + WARN_ONCE(1, "balloon inflation failed to enqueue page\n"); + return -EFAULT; + } + list_del(&page->lru); + balloon_page_insert(b_dev_info, page); + unlock_page(page); + __count_vm_event(BALLOON_INFLATE); + return 0; +} + +/** + * balloon_page_list_enqueue() - inserts a list of pages into the balloon page + * list. + * @b_dev_info: balloon device descriptor where we will insert a new page to + * @pages: pages to enqueue - allocated using balloon_page_alloc. + * + * Driver must call it to properly enqueue a balloon pages before definitively + * removing it from the guest system. + */ +void balloon_page_list_enqueue(struct balloon_dev_info *b_dev_info, + struct list_head *pages) +{ + struct page *page, *tmp; + unsigned long flags; + + spin_lock_irqsave(&b_dev_info->pages_lock, flags); + list_for_each_entry_safe(page, tmp, pages, lru) + balloon_page_enqueue_one(b_dev_info, page); + spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); +} +EXPORT_SYMBOL_GPL(balloon_page_list_enqueue); + +/** + * balloon_page_list_dequeue() - removes pages from balloon's page list and + * returns a list of the pages. + * @b_dev_info: balloon device decriptor where we will grab a page from. + * @pages: pointer to the list of pages that would be returned to the caller. + * @n_req_pages: number of requested pages. + * + * Driver must call it to properly de-allocate a previous enlisted balloon pages + * before definetively releasing it back to the guest system. This function + * tries to remove @n_req_pages from the ballooned pages and return it to the + * caller in the @pages list. + * + * Note that this function may fail to dequeue some pages temporarily empty due + * to compaction isolated pages. + * + * Return: number of pages that were added to the @pages list. + */ +int balloon_page_list_dequeue(struct balloon_dev_info *b_dev_info, + struct list_head *pages, int n_req_pages) +{ + struct page *page, *tmp; + unsigned long flags; + int n_pages = 0; + + spin_lock_irqsave(&b_dev_info->pages_lock, flags); + list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { + /* + * Block others from accessing the 'page' while we get around + * establishing additional references and preparing the 'page' + * to be released by the balloon driver. + */ + if (!trylock_page(page)) + continue; + + if (IS_ENABLED(CONFIG_BALLOON_COMPACTION) && + PageIsolated(page)) { + /* raced with isolation */ + unlock_page(page); + continue; + } + balloon_page_delete(page); + __count_vm_event(BALLOON_DEFLATE); + unlock_page(page); + list_add(&page->lru, pages); + if (++n_pages >= n_req_pages) + break; + } + spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); + + return n_pages; +} +EXPORT_SYMBOL_GPL(balloon_page_list_dequeue); + /* * balloon_page_alloc - allocates a new page for insertion into the balloon * page list. @@ -44,17 +138,9 @@ void balloon_page_enqueue(struct balloon_dev_info *b_dev_info, { unsigned long flags; - /* - * Block others from accessing the 'page' when we get around to - * establishing additional references. We should be the only one - * holding a reference to the 'page' at this point. - */ - BUG_ON(!trylock_page(page)); spin_lock_irqsave(&b_dev_info->pages_lock, flags); - balloon_page_insert(b_dev_info, page); - __count_vm_event(BALLOON_INFLATE); + balloon_page_enqueue_one(b_dev_info, page); spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); - unlock_page(page); } EXPORT_SYMBOL_GPL(balloon_page_enqueue); @@ -71,36 +157,13 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); */ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { - struct page *page, *tmp; unsigned long flags; - bool dequeued_page; + LIST_HEAD(pages); + int n_pages; - dequeued_page = false; - spin_lock_irqsave(&b_dev_info->pages_lock, flags); - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { - /* - * Block others from accessing the 'page' while we get around - * establishing additional references and preparing the 'page' - * to be released by the balloon driver. - */ - if (trylock_page(page)) { -#ifdef CONFIG_BALLOON_COMPACTION - if (PageIsolated(page)) { - /* raced with isolation */ - unlock_page(page); - continue; - } -#endif - balloon_page_delete(page); - __count_vm_event(BALLOON_DEFLATE); - unlock_page(page); - dequeued_page = true; - break; - } - } - spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); + n_pages = balloon_page_list_dequeue(b_dev_info, &pages, 1); - if (!dequeued_page) { + if (n_pages != 1) { /* * If we are unable to dequeue a balloon page because the page * list is empty and there is no isolated pages, then something @@ -113,9 +176,9 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) !b_dev_info->isolated_pages)) BUG(); spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); - page = NULL; + return NULL; } - return page; + return list_first_entry(&pages, struct page, lru); } EXPORT_SYMBOL_GPL(balloon_page_dequeue);