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 X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 EEC00C0044C for ; Mon, 5 Nov 2018 13:02:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1E7B20819 for ; Mon, 5 Nov 2018 13:02:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C1E7B20819 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729843AbeKEWVw (ORCPT ); Mon, 5 Nov 2018 17:21:52 -0500 Received: from mx2.suse.de ([195.135.220.15]:42528 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728136AbeKEWVv (ORCPT ); Mon, 5 Nov 2018 17:21:51 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 8CC77AFE2; Mon, 5 Nov 2018 13:02:10 +0000 (UTC) Date: Mon, 5 Nov 2018 14:02:09 +0100 From: Michal Hocko To: Kuo-Hsin Yang Cc: linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, Chris Wilson , Joonas Lahtinen , Peter Zijlstra , Andrew Morton , Dave Hansen Subject: Re: [PATCH v4] mm, drm/i915: mark pinned shmemfs pages as unevictable Message-ID: <20181105130209.GI4361@dhcp22.suse.cz> References: <20181105111348.182492-1-vovoy@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181105111348.182492-1-vovoy@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 05-11-18 19:13:48, Kuo-Hsin Yang wrote: > The i915 driver uses shmemfs to allocate backing storage for gem > objects. These shmemfs pages can be pinned (increased ref count) by > shmem_read_mapping_page_gfp(). When a lot of pages are pinned, vmscan > wastes a lot of time scanning these pinned pages. In some extreme case, > all pages in the inactive anon lru are pinned, and only the inactive > anon lru is scanned due to inactive_ratio, the system cannot swap and > invokes the oom-killer. Mark these pinned pages as unevictable to speed > up vmscan. > > Export pagevec API check_move_unevictable_pages(). Thanks for reworking the patch. This looks much more to my taste. At least the mm part. I haven't really looked at the the drm part. Just a nit below > This patch was inspired by Chris Wilson's change [1]. > > [1]: https://patchwork.kernel.org/patch/9768741/ I would recommend using msg-id based url. > Cc: Chris Wilson > Cc: Michal Hocko > Cc: Joonas Lahtinen > Cc: Peter Zijlstra > Cc: Andrew Morton > Cc: Dave Hansen > Signed-off-by: Kuo-Hsin Yang other than that Acked-by: Michal Hocko [...] > @@ -4184,15 +4185,13 @@ int page_evictable(struct page *page) > > #ifdef CONFIG_SHMEM > /** > - * check_move_unevictable_pages - check pages for evictability and move to appropriate zone lru list > - * @pages: array of pages to check > - * @nr_pages: number of pages to check > + * check_move_unevictable_pages - move evictable pages to appropriate evictable > + * lru lists I am not sure this is an improvement. I would just keep the original wording. It is not great either but the explicit note about check for evictability sounds like a better fit to me. > + * @pvec: pagevec with pages to check > * > - * Checks pages for evictability and moves them to the appropriate lru list. > - * > - * This function is only used for SysV IPC SHM_UNLOCK. > + * This function is only used to move shmem pages. I do not really see anything that would be shmem specific here. We can use this function for any LRU pages unless I am missing something obscure. I would just drop the last sentence. A note that this function should be only used for LRU pages would be nice. > */ > -void check_move_unevictable_pages(struct page **pages, int nr_pages) > +void check_move_unevictable_pages(struct pagevec *pvec) > { > struct lruvec *lruvec; > struct pglist_data *pgdat = NULL; > @@ -4200,8 +4199,8 @@ void check_move_unevictable_pages(struct page **pages, int nr_pages) > int pgrescued = 0; > int i; > > - for (i = 0; i < nr_pages; i++) { > - struct page *page = pages[i]; > + for (i = 0; i < pvec->nr; i++) { > + struct page *page = pvec->pages[i]; > struct pglist_data *pagepgdat = page_pgdat(page); > > pgscanned++; > @@ -4233,4 +4232,5 @@ void check_move_unevictable_pages(struct page **pages, int nr_pages) > spin_unlock_irq(&pgdat->lru_lock); > } > } > +EXPORT_SYMBOL(check_move_unevictable_pages); > #endif /* CONFIG_SHMEM */ > -- > 2.19.1.930.g4563a0d9d0-goog > -- Michal Hocko SUSE Labs