From patchwork Wed Jun 13 01:11:01 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 9244 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id AB7A423E49 for ; Wed, 13 Jun 2012 01:11:21 +0000 (UTC) Received: from mail-yx0-f180.google.com (mail-yx0-f180.google.com [209.85.213.180]) by fiordland.canonical.com (Postfix) with ESMTP id 7B8B1A1818F for ; Wed, 13 Jun 2012 01:11:21 +0000 (UTC) Received: by mail-yx0-f180.google.com with SMTP id q6so131474yen.11 for ; Tue, 12 Jun 2012 18:11:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-forwarded-to:x-forwarded-for:delivered-to:received-spf:from:to:cc :subject:date:message-id:x-mailer:in-reply-to:references :x-content-scanned:x-cbid:x-gm-message-state; bh=meM6nke0DzJwWIxYgyg3JgFpgwFPA9icpyFtRsEQneE=; b=EQNZ3axM50fD0G90jHdTZsh49NNQkgEcfUWWZ9ueHNqi3u65tKIk44EwvVdm5mSGCA panHWpAT4sol32NgtkYVUNccO42CD5WW3UtmvXEBzlz8W50s0sSphHj+HMurrw3N4D+c qQJDLHD5fGY+7N+YWReQXqfXZmGz+p3614G9OrUJQxjkgXxw2B07qp23xiXkMAiNcRoA FymO/138310+Hpaqc6Av0a9vunYo9r3mlS08jx5EaLxOMdoc1kzbYWH3nn8oxGiBZezh fJgCeTPN3IBvUVMt7PQd/p303uJ9lFJZvJbljGWuUq5BhhOoDp7kJgTc51D65BzzhC48 jPEw== Received: by 10.50.160.198 with SMTP id xm6mr9718189igb.0.1339549880822; Tue, 12 Jun 2012 18:11:20 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.231.24.148 with SMTP id v20csp198992ibb; Tue, 12 Jun 2012 18:11:19 -0700 (PDT) Received: by 10.68.193.195 with SMTP id hq3mr44347057pbc.30.1339549879694; Tue, 12 Jun 2012 18:11:19 -0700 (PDT) Received: from e32.co.us.ibm.com (e32.co.us.ibm.com. 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Violators will be prosecuted; Tue, 12 Jun 2012 19:11:16 -0600 Received: from d03relay05.boulder.ibm.com (d03relay05.boulder.ibm.com [9.17.195.107]) by d03dlp02.boulder.ibm.com (Postfix) with ESMTP id 3C4F93E4004F; Wed, 13 Jun 2012 01:11:15 +0000 (WET) Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay05.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q5D1BAs0260566; Tue, 12 Jun 2012 19:11:11 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q5D1B8pp018459; Tue, 12 Jun 2012 19:11:10 -0600 Received: from kernel.beaverton.ibm.com (kernel.beaverton.ibm.com [9.47.67.96]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q5D1B8pv018440; Tue, 12 Jun 2012 19:11:08 -0600 Received: by kernel.beaverton.ibm.com (Postfix, from userid 1056) id ABC05C0627; Tue, 12 Jun 2012 18:11:06 -0700 (PDT) From: John Stultz To: LKML Cc: John Stultz , Andrew Morton , Android Kernel Team , Robert Love , Mel Gorman , Hugh Dickins , Dave Hansen , Rik van Riel , Dmitry Adamushko , Dave Chinner , Neil Brown , Andrea Righi , "Aneesh Kumar K.V" , Taras Glek , Mike Hommey , Jan Kara , KOSAKI Motohiro Subject: [PATCH 6/6] [RFC][HACK] mm: Change memory management of anonymous pages on swapless systems Date: Tue, 12 Jun 2012 18:11:01 -0700 Message-Id: <1339549862-653-7-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 1.7.3.2.146.gca209 In-Reply-To: <1339549862-653-1-git-send-email-john.stultz@linaro.org> References: <1339549862-653-1-git-send-email-john.stultz@linaro.org> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12061301-3270-0000-0000-0000072021F1 X-Gm-Message-State: ALoCoQkaokYUKDjvhfzLkJizs/vX7AcWcWPvySH+bE91BItxgg84uHKTxDYe+StHcrIaSx7mE32C Due to my newbie-ness, the following may not be precise, but I think it conveys the intent of what I'm trying to do here. Anonymous memory is tracked on two LRU lists: LRU_INACTIVE_ANON and LRU_ACTIVE_ANON. This split is useful when we need to free up pages and are trying to decide what to swap out. However, on systems that do no have swap, this partition is less clear. In many cases the code avoids aging active anonymous pages onto the inactive list. However in some cases pages do get moved to the inactive list, but we never call writepage, as there isn't anything to swap out. This patch changes some of the active/inactive list management of anonymous memory when there is no swap. In that case pages are always added to the active lru. The intent is that since anonymous pages cannot be swapped out, they all shoudld be active. The one exception is volatile pages, which can be moved to the inactive lru by calling deactivate_page(). In addition, I've changed the logic so we also do try to shrink the inactive anonymous lru, and call writepage. This should only be done if there are volatile pages on the inactive lru. This allows us to purge volatile pages in writepage when the system does not have swap. CC: Andrew Morton CC: Android Kernel Team CC: Robert Love CC: Mel Gorman CC: Hugh Dickins CC: Dave Hansen CC: Rik van Riel CC: Dmitry Adamushko CC: Dave Chinner CC: Neil Brown CC: Andrea Righi CC: Aneesh Kumar K.V CC: Taras Glek CC: Mike Hommey CC: Jan Kara CC: KOSAKI Motohiro Signed-off-by: John Stultz --- include/linux/pagevec.h | 5 +---- include/linux/swap.h | 23 +++++++++++++++-------- mm/swap.c | 13 ++++++++++++- mm/vmscan.c | 9 --------- 4 files changed, 28 insertions(+), 22 deletions(-) diff --git a/include/linux/pagevec.h b/include/linux/pagevec.h index 2aa12b8..e1312a5 100644 --- a/include/linux/pagevec.h +++ b/include/linux/pagevec.h @@ -22,6 +22,7 @@ struct pagevec { void __pagevec_release(struct pagevec *pvec); void __pagevec_lru_add(struct pagevec *pvec, enum lru_list lru); +void __pagevec_lru_add_anon(struct pagevec *pvec); unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping, pgoff_t start, unsigned nr_pages); unsigned pagevec_lookup_tag(struct pagevec *pvec, @@ -64,10 +65,6 @@ static inline void pagevec_release(struct pagevec *pvec) __pagevec_release(pvec); } -static inline void __pagevec_lru_add_anon(struct pagevec *pvec) -{ - __pagevec_lru_add(pvec, LRU_INACTIVE_ANON); -} static inline void __pagevec_lru_add_active_anon(struct pagevec *pvec) { diff --git a/include/linux/swap.h b/include/linux/swap.h index c84ec68..639936f 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -238,14 +238,6 @@ extern void swap_setup(void); extern void add_page_to_unevictable_list(struct page *page); -/** - * lru_cache_add: add a page to the page lists - * @page: the page to add - */ -static inline void lru_cache_add_anon(struct page *page) -{ - __lru_cache_add(page, LRU_INACTIVE_ANON); -} static inline void lru_cache_add_file(struct page *page) { @@ -474,5 +466,20 @@ mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent) } #endif /* CONFIG_SWAP */ + +/** + * lru_cache_add: add a page to the page lists + * @page: the page to add + */ +static inline void lru_cache_add_anon(struct page *page) +{ + int lru = LRU_INACTIVE_ANON; + if (!total_swap_pages) + lru = LRU_ACTIVE_ANON; + + __lru_cache_add(page, lru); +} + + #endif /* __KERNEL__*/ #endif /* _LINUX_SWAP_H */ diff --git a/mm/swap.c b/mm/swap.c index 4e7e2ec..f35df46 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -691,7 +691,7 @@ void lru_add_page_tail(struct page *page, struct page *page_tail, SetPageLRU(page_tail); if (page_evictable(page_tail, NULL)) { - if (PageActive(page)) { + if (PageActive(page) || !total_swap_pages) { SetPageActive(page_tail); active = 1; lru = LRU_ACTIVE_ANON; @@ -755,6 +755,17 @@ void __pagevec_lru_add(struct pagevec *pvec, enum lru_list lru) } EXPORT_SYMBOL(__pagevec_lru_add); + +void __pagevec_lru_add_anon(struct pagevec *pvec) +{ + if (!total_swap_pages) + __pagevec_lru_add(pvec, LRU_ACTIVE_ANON); + else + __pagevec_lru_add(pvec, LRU_INACTIVE_ANON); +} +EXPORT_SYMBOL(__pagevec_lru_add_anon); + + /** * pagevec_lookup - gang pagecache lookup * @pvec: Where the resulting pages are placed diff --git a/mm/vmscan.c b/mm/vmscan.c index eeb3bc9..52d8ad9 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1597,15 +1597,6 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, if (!global_reclaim(sc)) force_scan = true; - /* If we have no swap space, do not bother scanning anon pages. */ - if (!sc->may_swap || (nr_swap_pages <= 0)) { - noswap = 1; - fraction[0] = 0; - fraction[1] = 1; - denominator = 1; - goto out; - } - anon = get_lru_size(lruvec, LRU_ACTIVE_ANON) + get_lru_size(lruvec, LRU_INACTIVE_ANON); file = get_lru_size(lruvec, LRU_ACTIVE_FILE) +