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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 CBC4DC4332D for ; Sat, 13 Mar 2021 07:59:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B8A3D64ECE for ; Sat, 13 Mar 2021 07:59:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233468AbhCMH6l (ORCPT ); Sat, 13 Mar 2021 02:58:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58990 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232705AbhCMH6I (ORCPT ); Sat, 13 Mar 2021 02:58:08 -0500 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5BF1C061761 for ; Fri, 12 Mar 2021 23:58:07 -0800 (PST) Received: by mail-qk1-x749.google.com with SMTP id i188so19867209qkd.7 for ; Fri, 12 Mar 2021 23:58:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Y7HI6Iu8cEpN4/cKvfcV1g+GhNxN+RuODBCey3P9ub4=; b=Yxxt5mdzkudc9JV5Q09FDlj0cvp1kmfCXxaVjGD5K0eCTz/So1vsV5U0rgmXDgA+oo I0A6T+8UZJmQiHjXDXECTBckUL0jnXMRgRm7XVaG53YB34iWjqO40F4CKKEh9+/OoVRc G0AmzhscUbBJ/kam3+ejsn6XT8HmEmL1E1JV5ccYQd+ZntwFpRDTuwloc8JJwbzlOPz6 /TmQCN3DlJawauHo+hK8esqlLBqlUo0Hc3ctZf6lI6jfTJ6xP19kgHg147e6ddt/0Gru 4TRJ0LLQctTAhahAckLyUPLY8X0ofJQRXl5IFVx653ZZtEjcg5D9kIYZI+E7lddJGHTM WCSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Y7HI6Iu8cEpN4/cKvfcV1g+GhNxN+RuODBCey3P9ub4=; b=IhPlACmRhDBTPdmCHr0Oo1gV9hWUVpXkJQAh9lb+wytYYH7q3Kq7e+gKEZ0WvXAxP5 HCkzZEXo0KeDSrSNfpNxh8YUrLoNxRyc67U6jB0GE7MI8jH4hpyANf1w/gGK8VfBJVP6 HEd0MgT957tjxC4w5s2bFihlDvVujIJLQPYS+KO24VxvtbXLbjOayAHo8fH37VLxQ9U2 nOkP5ADzrpG+7bfsI2JutdLL5J6KjOX/ix5YTdFiiS1XlDgF+UDcwUkwnju04+gULHCK SWuoOrT0DOfqlcQ4ome3RlXCB1UU/RCIPUUA06Y1a7h09m5zX6C1pqv0hnFWEk1Ehj8t sE+g== X-Gm-Message-State: AOAM533FjF5wfsmOCevkWqM2Zy0aRGz/n1+9ldB7hstZ21MlGbAcnU9S iwofL/8D5KT2K6tTLoKvMx4do3+86Ss= X-Google-Smtp-Source: ABdhPJwaHhrMfJqAPFj0pJIH6XbHZzHvvKGA6xcQa4GVhmvHaXMnKKa3+FEHfHSk+8gEmFOMqKskjMN6bjo= X-Received: from yuzhao.bld.corp.google.com ([2620:15c:183:200:f931:d3e4:faa0:4f74]) (user=yuzhao job=sendgmr) by 2002:ad4:50c7:: with SMTP id e7mr1747988qvq.58.1615622286760; Fri, 12 Mar 2021 23:58:06 -0800 (PST) Date: Sat, 13 Mar 2021 00:57:41 -0700 In-Reply-To: <20210313075747.3781593-1-yuzhao@google.com> Message-Id: <20210313075747.3781593-9-yuzhao@google.com> Mime-Version: 1.0 References: <20210313075747.3781593-1-yuzhao@google.com> X-Mailer: git-send-email 2.31.0.rc2.261.g7f71774620-goog Subject: [PATCH v1 08/14] mm/vmscan.c: refactor shrink_node() From: Yu Zhao To: linux-mm@kvack.org Cc: Alex Shi , Andrew Morton , Dave Hansen , Hillf Danton , Johannes Weiner , Joonsoo Kim , Matthew Wilcox , Mel Gorman , Michal Hocko , Roman Gushchin , Vlastimil Babka , Wei Yang , Yang Shi , Ying Huang , linux-kernel@vger.kernel.org, page-reclaim@google.com, Yu Zhao Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Archived-At: List-Archive: List-Post: Heuristics in shrink_node() are rather independent and can be refactored into a separate function to improve readability. Signed-off-by: Yu Zhao --- mm/vmscan.c | 186 +++++++++++++++++++++++++++------------------------- 1 file changed, 98 insertions(+), 88 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 562e87cbd7a1..1a24d2e0a4cb 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2224,6 +2224,103 @@ enum scan_balance { SCAN_FILE, }; +static void prepare_scan_count(pg_data_t *pgdat, struct scan_control *sc) +{ + unsigned long file; + struct lruvec *target_lruvec; + + target_lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup, pgdat); + + /* + * Determine the scan balance between anon and file LRUs. + */ + spin_lock_irq(&target_lruvec->lru_lock); + sc->anon_cost = target_lruvec->anon_cost; + sc->file_cost = target_lruvec->file_cost; + spin_unlock_irq(&target_lruvec->lru_lock); + + /* + * Target desirable inactive:active list ratios for the anon + * and file LRU lists. + */ + if (!sc->force_deactivate) { + unsigned long refaults; + + refaults = lruvec_page_state(target_lruvec, + WORKINGSET_ACTIVATE_ANON); + if (refaults != target_lruvec->refaults[0] || + inactive_is_low(target_lruvec, LRU_INACTIVE_ANON)) + sc->may_deactivate |= DEACTIVATE_ANON; + else + sc->may_deactivate &= ~DEACTIVATE_ANON; + + /* + * When refaults are being observed, it means a new + * workingset is being established. Deactivate to get + * rid of any stale active pages quickly. + */ + refaults = lruvec_page_state(target_lruvec, + WORKINGSET_ACTIVATE_FILE); + if (refaults != target_lruvec->refaults[1] || + inactive_is_low(target_lruvec, LRU_INACTIVE_FILE)) + sc->may_deactivate |= DEACTIVATE_FILE; + else + sc->may_deactivate &= ~DEACTIVATE_FILE; + } else + sc->may_deactivate = DEACTIVATE_ANON | DEACTIVATE_FILE; + + /* + * If we have plenty of inactive file pages that aren't + * thrashing, try to reclaim those first before touching + * anonymous pages. + */ + file = lruvec_page_state(target_lruvec, NR_INACTIVE_FILE); + if (file >> sc->priority && !(sc->may_deactivate & DEACTIVATE_FILE)) + sc->cache_trim_mode = 1; + else + sc->cache_trim_mode = 0; + + /* + * Prevent the reclaimer from falling into the cache trap: as + * cache pages start out inactive, every cache fault will tip + * the scan balance towards the file LRU. And as the file LRU + * shrinks, so does the window for rotation from references. + * This means we have a runaway feedback loop where a tiny + * thrashing file LRU becomes infinitely more attractive than + * anon pages. Try to detect this based on file LRU size. + */ + if (!cgroup_reclaim(sc)) { + unsigned long total_high_wmark = 0; + unsigned long free, anon; + int z; + + free = sum_zone_node_page_state(pgdat->node_id, NR_FREE_PAGES); + file = node_page_state(pgdat, NR_ACTIVE_FILE) + + node_page_state(pgdat, NR_INACTIVE_FILE); + + for (z = 0; z < MAX_NR_ZONES; z++) { + struct zone *zone = &pgdat->node_zones[z]; + + if (!managed_zone(zone)) + continue; + + total_high_wmark += high_wmark_pages(zone); + } + + /* + * Consider anon: if that's low too, this isn't a + * runaway file reclaim problem, but rather just + * extreme pressure. Reclaim as per usual then. + */ + anon = node_page_state(pgdat, NR_INACTIVE_ANON); + + sc->file_is_tiny = + file + free <= total_high_wmark && + !(sc->may_deactivate & DEACTIVATE_ANON) && + anon >> sc->priority; + } +} + /* * Determine how aggressively the anon and file LRU lists should be * scanned. The relative value of each set of LRU lists is determined @@ -2669,7 +2766,6 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) unsigned long nr_reclaimed, nr_scanned; struct lruvec *target_lruvec; bool reclaimable = false; - unsigned long file; target_lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup, pgdat); @@ -2679,93 +2775,7 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) nr_reclaimed = sc->nr_reclaimed; nr_scanned = sc->nr_scanned; - /* - * Determine the scan balance between anon and file LRUs. - */ - spin_lock_irq(&target_lruvec->lru_lock); - sc->anon_cost = target_lruvec->anon_cost; - sc->file_cost = target_lruvec->file_cost; - spin_unlock_irq(&target_lruvec->lru_lock); - - /* - * Target desirable inactive:active list ratios for the anon - * and file LRU lists. - */ - if (!sc->force_deactivate) { - unsigned long refaults; - - refaults = lruvec_page_state(target_lruvec, - WORKINGSET_ACTIVATE_ANON); - if (refaults != target_lruvec->refaults[0] || - inactive_is_low(target_lruvec, LRU_INACTIVE_ANON)) - sc->may_deactivate |= DEACTIVATE_ANON; - else - sc->may_deactivate &= ~DEACTIVATE_ANON; - - /* - * When refaults are being observed, it means a new - * workingset is being established. Deactivate to get - * rid of any stale active pages quickly. - */ - refaults = lruvec_page_state(target_lruvec, - WORKINGSET_ACTIVATE_FILE); - if (refaults != target_lruvec->refaults[1] || - inactive_is_low(target_lruvec, LRU_INACTIVE_FILE)) - sc->may_deactivate |= DEACTIVATE_FILE; - else - sc->may_deactivate &= ~DEACTIVATE_FILE; - } else - sc->may_deactivate = DEACTIVATE_ANON | DEACTIVATE_FILE; - - /* - * If we have plenty of inactive file pages that aren't - * thrashing, try to reclaim those first before touching - * anonymous pages. - */ - file = lruvec_page_state(target_lruvec, NR_INACTIVE_FILE); - if (file >> sc->priority && !(sc->may_deactivate & DEACTIVATE_FILE)) - sc->cache_trim_mode = 1; - else - sc->cache_trim_mode = 0; - - /* - * Prevent the reclaimer from falling into the cache trap: as - * cache pages start out inactive, every cache fault will tip - * the scan balance towards the file LRU. And as the file LRU - * shrinks, so does the window for rotation from references. - * This means we have a runaway feedback loop where a tiny - * thrashing file LRU becomes infinitely more attractive than - * anon pages. Try to detect this based on file LRU size. - */ - if (!cgroup_reclaim(sc)) { - unsigned long total_high_wmark = 0; - unsigned long free, anon; - int z; - - free = sum_zone_node_page_state(pgdat->node_id, NR_FREE_PAGES); - file = node_page_state(pgdat, NR_ACTIVE_FILE) + - node_page_state(pgdat, NR_INACTIVE_FILE); - - for (z = 0; z < MAX_NR_ZONES; z++) { - struct zone *zone = &pgdat->node_zones[z]; - if (!managed_zone(zone)) - continue; - - total_high_wmark += high_wmark_pages(zone); - } - - /* - * Consider anon: if that's low too, this isn't a - * runaway file reclaim problem, but rather just - * extreme pressure. Reclaim as per usual then. - */ - anon = node_page_state(pgdat, NR_INACTIVE_ANON); - - sc->file_is_tiny = - file + free <= total_high_wmark && - !(sc->may_deactivate & DEACTIVATE_ANON) && - anon >> sc->priority; - } + prepare_scan_count(pgdat, sc); shrink_node_memcgs(pgdat, sc); -- 2.31.0.rc2.261.g7f71774620-goog