From patchwork Wed Oct 18 07:59:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mel Gorman X-Patchwork-Id: 10013979 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F10C860211 for ; Wed, 18 Oct 2017 08:00:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E450328390 for ; Wed, 18 Oct 2017 08:00:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D953128AF0; Wed, 18 Oct 2017 08:00:44 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 519CC28390 for ; Wed, 18 Oct 2017 08:00:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935828AbdJRH74 (ORCPT ); Wed, 18 Oct 2017 03:59:56 -0400 Received: from outbound-smtp10.blacknight.com ([46.22.139.15]:56161 "EHLO outbound-smtp10.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933553AbdJRH7y (ORCPT ); Wed, 18 Oct 2017 03:59:54 -0400 Received: from mail.blacknight.com (pemlinmail04.blacknight.ie [81.17.254.17]) by outbound-smtp10.blacknight.com (Postfix) with ESMTPS id 7DFBD1C2F87 for ; Wed, 18 Oct 2017 08:59:53 +0100 (IST) Received: (qmail 32168 invoked from network); 18 Oct 2017 07:59:53 -0000 Received: from unknown (HELO stampy.163woodhaven.lan) (mgorman@techsingularity.net@[37.228.236.208]) by 81.17.254.9 with ESMTPA; 18 Oct 2017 07:59:53 -0000 From: Mel Gorman To: Andrew Morton Cc: Linux-MM , Linux-FSDevel , LKML , Jan Kara , Andi Kleen , Dave Hansen , Dave Chinner , Mel Gorman Subject: [PATCH 1/8] mm, page_alloc: Enable/disable IRQs once when freeing a list of pages Date: Wed, 18 Oct 2017 08:59:45 +0100 Message-Id: <20171018075952.10627-2-mgorman@techsingularity.net> X-Mailer: git-send-email 2.14.0 In-Reply-To: <20171018075952.10627-1-mgorman@techsingularity.net> References: <20171018075952.10627-1-mgorman@techsingularity.net> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Freeing a list of pages current enables/disables IRQs for each page freed. This patch splits freeing a list of pages into two operations -- preparing the pages for freeing and the actual freeing. This is a tradeoff - we're taking two passes of the list to free in exchange for avoiding multiple enable/disable of IRQs. sparsetruncate (tiny) 4.14.0-rc4 4.14.0-rc4 janbatch-v1r1 oneirq-v1r1 Min Time 149.00 ( 0.00%) 141.00 ( 5.37%) 1st-qrtle Time 150.00 ( 0.00%) 142.00 ( 5.33%) 2nd-qrtle Time 151.00 ( 0.00%) 142.00 ( 5.96%) 3rd-qrtle Time 151.00 ( 0.00%) 143.00 ( 5.30%) Max-90% Time 153.00 ( 0.00%) 144.00 ( 5.88%) Max-95% Time 155.00 ( 0.00%) 147.00 ( 5.16%) Max-99% Time 201.00 ( 0.00%) 195.00 ( 2.99%) Max Time 236.00 ( 0.00%) 230.00 ( 2.54%) Amean Time 152.65 ( 0.00%) 144.37 ( 5.43%) Stddev Time 9.78 ( 0.00%) 10.44 ( -6.72%) Coeff Time 6.41 ( 0.00%) 7.23 ( -12.84%) Best99%Amean Time 152.07 ( 0.00%) 143.72 ( 5.50%) Best95%Amean Time 150.75 ( 0.00%) 142.37 ( 5.56%) Best90%Amean Time 150.59 ( 0.00%) 142.19 ( 5.58%) Best75%Amean Time 150.36 ( 0.00%) 141.92 ( 5.61%) Best50%Amean Time 150.04 ( 0.00%) 141.69 ( 5.56%) Best25%Amean Time 149.85 ( 0.00%) 141.38 ( 5.65%) With a tiny number of files, each file truncated has resident page cache and it shows that time to truncate is roughtly 5-6% with some minor jitter. 4.14.0-rc4 4.14.0-rc4 janbatch-v1r1 oneirq-v1r1 Hmean SeqCreate ops 65.27 ( 0.00%) 81.86 ( 25.43%) Hmean SeqCreate read 39.48 ( 0.00%) 47.44 ( 20.16%) Hmean SeqCreate del 24963.95 ( 0.00%) 26319.99 ( 5.43%) Hmean RandCreate ops 65.47 ( 0.00%) 82.01 ( 25.26%) Hmean RandCreate read 42.04 ( 0.00%) 51.75 ( 23.09%) Hmean RandCreate del 23377.66 ( 0.00%) 23764.79 ( 1.66%) As expected, there is a small gain for the delete operation. Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka --- mm/page_alloc.c | 58 +++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 44 insertions(+), 14 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 77e4d3c5c57b..167e163cf733 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2590,24 +2590,26 @@ void mark_free_pages(struct zone *zone) } #endif /* CONFIG_PM */ -/* - * Free a 0-order page - * cold == true ? free a cold page : free a hot page - */ -void free_hot_cold_page(struct page *page, bool cold) +static bool free_hot_cold_page_prepare(struct page *page, unsigned long pfn) { - struct zone *zone = page_zone(page); - struct per_cpu_pages *pcp; - unsigned long flags; - unsigned long pfn = page_to_pfn(page); int migratetype; if (!free_pcp_prepare(page)) - return; + return false; migratetype = get_pfnblock_migratetype(page, pfn); set_pcppage_migratetype(page, migratetype); - local_irq_save(flags); + return true; +} + +static void free_hot_cold_page_commit(struct page *page, unsigned long pfn, + bool cold) +{ + struct zone *zone = page_zone(page); + struct per_cpu_pages *pcp; + int migratetype; + + migratetype = get_pcppage_migratetype(page); __count_vm_event(PGFREE); /* @@ -2620,7 +2622,7 @@ void free_hot_cold_page(struct page *page, bool cold) if (migratetype >= MIGRATE_PCPTYPES) { if (unlikely(is_migrate_isolate(migratetype))) { free_one_page(zone, page, pfn, 0, migratetype); - goto out; + return; } migratetype = MIGRATE_MOVABLE; } @@ -2636,8 +2638,22 @@ void free_hot_cold_page(struct page *page, bool cold) free_pcppages_bulk(zone, batch, pcp); pcp->count -= batch; } +} -out: +/* + * Free a 0-order page + * cold == true ? free a cold page : free a hot page + */ +void free_hot_cold_page(struct page *page, bool cold) +{ + unsigned long flags; + unsigned long pfn = page_to_pfn(page); + + if (!free_hot_cold_page_prepare(page, pfn)) + return; + + local_irq_save(flags); + free_hot_cold_page_commit(page, pfn, cold); local_irq_restore(flags); } @@ -2647,11 +2663,25 @@ void free_hot_cold_page(struct page *page, bool cold) void free_hot_cold_page_list(struct list_head *list, bool cold) { struct page *page, *next; + unsigned long flags, pfn; + + /* Prepare pages for freeing */ + list_for_each_entry_safe(page, next, list, lru) { + pfn = page_to_pfn(page); + if (!free_hot_cold_page_prepare(page, pfn)) + list_del(&page->lru); + page->private = pfn; + } + local_irq_save(flags); list_for_each_entry_safe(page, next, list, lru) { + unsigned long pfn = page->private; + + page->private = 0; trace_mm_page_free_batched(page, cold); - free_hot_cold_page(page, cold); + free_hot_cold_page_commit(page, pfn, cold); } + local_irq_restore(flags); } /*