From patchwork Thu Feb 2 23:32:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13126808 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C05E9C6379F for ; Thu, 2 Feb 2023 23:32:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232102AbjBBXch (ORCPT ); Thu, 2 Feb 2023 18:32:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233205AbjBBXch (ORCPT ); Thu, 2 Feb 2023 18:32:37 -0500 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2B51CA09 for ; Thu, 2 Feb 2023 15:32:35 -0800 (PST) Received: by mail-pf1-x449.google.com with SMTP id f15-20020a62380f000000b0058db55a8d7aso1694968pfa.21 for ; Thu, 02 Feb 2023 15:32:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=jMfzYGpjLscA+cSHKjv+qODVcyrrlHVghJg0aaO0KBk=; b=OvrbEiCpGPYcK17eFl9Y8Nb0T74F1qeKRRPkLoOMDwdi/dRXxR6NuAQjAW9zXsUR0O NeVP3CBQfbmSZRDn3VjHms7iVR+lkrD9000HVofhlapWdM0H6OVWwh++RAm98vZ+5dhx bufiNX/dvrtyw3cumBPhgl4x+7y0E+G53ahhpnQuHNJSZ5luwRgX/jLAWcgel9dI3QjA SRu0TbgVgGpsoeFXfGAVryIKlsdRcV06r0T1Ttoz+3041WIcgTRlSdDg+usnZ1TMOPDz Rf9IFZN9Y+yLtQ9bRc+UBoG9YZg5Aztk+JWK5oqw6+zVPOqc/gIiW520ZtukWzKTIrxg lJvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=jMfzYGpjLscA+cSHKjv+qODVcyrrlHVghJg0aaO0KBk=; b=v+ns2Y6KWNNN3oOIjpMmzzsuIKfZ24MjtVsaYDtlLNziRTQU7Z7SZAwkQ17wTfW6ts vcqzQ2PSCRG32FQ9UPlS8i8YSHuz/eOUjxrLmm8QEY3brOH471UNgIulw5r/PZkdPmHl EvJXCF42MZgWSw+XZ5To4nOZv9/Zffpi+bo+8R868avzsPrSAjEBkDisWmNmzJmr6k6f 3Wh8rH/tEpj8If6N2rVjqY/HzsOYUUmmmqv8kpJSfTdpbt6heQNYPVGHO2ERY1bADPhy FzEtOsJOUTFA54uBiZqSbELL9MVPnoSEWSch9lSWkq+J7Vcy3qlinp65ENx/Hr/dZlBz RjIw== X-Gm-Message-State: AO0yUKVRy77S+Q0wGRJbkgkGsEfRMEru/laLQY4pw3eVDMoATomlhSFK VHDBrLWIRYCufVsfYoGi32pVJVdLdSI7b7Vr X-Google-Smtp-Source: AK7set9GQneKggPkDbKmlHsZPDxNqqKNqpt3nFbEgf1JtVVy4xckZ6axh9mOcnrxgc0XPi+3Fc6kG5az9ihIBd8Y X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a17:90a:7f93:b0:22c:aacd:86c5 with SMTP id m19-20020a17090a7f9300b0022caacd86c5mr992815pjl.76.1675380755306; Thu, 02 Feb 2023 15:32:35 -0800 (PST) Date: Thu, 2 Feb 2023 23:32:28 +0000 In-Reply-To: <20230202233229.3895713-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230202233229.3895713-1-yosryahmed@google.com> X-Mailer: git-send-email 2.39.1.519.gcb327c4b5f-goog Message-ID: <20230202233229.3895713-2-yosryahmed@google.com> Subject: [RFC PATCH v1 1/2] mm: vmscan: refactor updating reclaimed pages in reclaim_state From: Yosry Ahmed To: Alexander Viro , "Darrick J. Wong" , Christoph Lameter , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "Matthew Wilcox (Oracle)" , Miaohe Lin , David Hildenbrand , Johannes Weiner , Peter Xu , NeilBrown , Shakeel Butt , Michal Hocko Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org During reclaim, we keep track of pages reclaimed from other means than LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab, which we stash a pointer to in current task_struct. However, we keep track of more than just reclaimed slab pages through this. We also use it for clean file pages dropped through pruned inodes, and xfs buffer pages freed. Rename reclaimed_slab to reclaimed, and add a helper function that wraps updating it through current. Signed-off-by: Yosry Ahmed --- fs/inode.c | 3 +-- fs/xfs/xfs_buf.c | 3 +-- include/linux/swap.h | 5 ++++- mm/slab.c | 3 +-- mm/slob.c | 6 ++---- mm/slub.c | 5 ++--- mm/vmscan.c | 17 +++++++++++++++-- 7 files changed, 26 insertions(+), 16 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index f453eb58fd03..adf0a7725054 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -863,8 +863,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item, __count_vm_events(KSWAPD_INODESTEAL, reap); else __count_vm_events(PGINODESTEAL, reap); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += reap; + report_freed_pages(reap); } iput(inode); spin_lock(lru_lock); diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 54c774af6e1c..060079f1e966 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -286,8 +286,7 @@ xfs_buf_free_pages( if (bp->b_pages[i]) __free_page(bp->b_pages[i]); } - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += bp->b_page_count; + report_freed_pages(bp->b_page_count); if (bp->b_pages != bp->b_page_array) kmem_free(bp->b_pages); diff --git a/include/linux/swap.h b/include/linux/swap.h index 2787b84eaf12..bc1d8b326453 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -153,13 +153,16 @@ union swap_header { * memory reclaim */ struct reclaim_state { - unsigned long reclaimed_slab; + /* pages reclaimed outside of LRU-based reclaim */ + unsigned long reclaimed; #ifdef CONFIG_LRU_GEN /* per-thread mm walk data */ struct lru_gen_mm_walk *mm_walk; #endif }; +void report_freed_pages(unsigned long pages); + #ifdef __KERNEL__ struct address_space; diff --git a/mm/slab.c b/mm/slab.c index 29300fc1289a..452db5913356 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1395,8 +1395,7 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; + report_freed_pages(1 << order); unaccount_slab(slab, order, cachep); __free_pages(folio_page(folio, 0), order); } diff --git a/mm/slob.c b/mm/slob.c index fe567fcfa3a3..71ee00e9dd46 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -61,7 +61,7 @@ #include #include -#include /* struct reclaim_state */ +#include /* report_freed_pages() */ #include #include #include @@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int order) { struct page *sp = virt_to_page(b); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; - + report_freed_pages(1 << order); mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, -(PAGE_SIZE << order)); __free_pages(sp, order); diff --git a/mm/slub.c b/mm/slub.c index 13459c69095a..5145ad2467e9 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -11,7 +11,7 @@ */ #include -#include /* struct reclaim_state */ +#include /* report_freed_pages() */ #include #include #include @@ -2063,8 +2063,7 @@ static void __free_slab(struct kmem_cache *s, struct slab *slab) /* Make the mapping reset visible before clearing the flag */ smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += pages; + report_freed_pages(pages); unaccount_slab(slab, order, s); __free_pages(folio_page(folio, 0), order); } diff --git a/mm/vmscan.c b/mm/vmscan.c index bd6637fcd8f9..63a27d2f6f31 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -204,6 +204,19 @@ static void set_task_reclaim_state(struct task_struct *task, task->reclaim_state = rs; } +/* + * reclaim_report_freed_pages: report pages freed outside of LRU-based reclaim + * @pages: number of pages freed + * + * If the current process is undergoing a reclaim operation, + * increment the number of reclaimed pages by @pages. + */ +void report_freed_pages(unsigned long pages) +{ + if (current->reclaim_state) + current->reclaim_state->reclaimed += pages; +} + LIST_HEAD(shrinker_list); DECLARE_RWSEM(shrinker_rwsem); @@ -6169,8 +6182,8 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) shrink_node_memcgs(pgdat, sc); if (reclaim_state) { - sc->nr_reclaimed += reclaim_state->reclaimed_slab; - reclaim_state->reclaimed_slab = 0; + sc->nr_reclaimed += reclaim_state->reclaimed; + reclaim_state->reclaimed = 0; } /* Record the subtree's reclaim efficiency */ From patchwork Thu Feb 2 23:32:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13126809 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20CF7C636D7 for ; Thu, 2 Feb 2023 23:32:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233251AbjBBXcj (ORCPT ); Thu, 2 Feb 2023 18:32:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233244AbjBBXci (ORCPT ); Thu, 2 Feb 2023 18:32:38 -0500 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE844183 for ; Thu, 2 Feb 2023 15:32:37 -0800 (PST) Received: by mail-pf1-x449.google.com with SMTP id k14-20020aa7972e000000b00593a8232ac3so1683074pfg.22 for ; Thu, 02 Feb 2023 15:32:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=0NNiCqwzESyAJCUAtzOveFlWcEoCPQvaoYU5oWya4UE=; b=hOhCADwPkxUGmi7V1P/nnFPjlarle5tUS/LLXkpE2OMQZSESuPz1Yg7ch5+w2lQPvZ Tg/E8g4ve+TuLwEeRfChTbEYbLJeSDJDBhmLL+z83Q3UbkFRR/7iALI3n//9YzuETtUk /td2TUtQtadczPSW8P9uXTi/L7bXWxzWMSBHRmqrt9SBSEfcBH/jtfBlcjWv7c1f+PLe QQJMnYWOv7ywl4B7eaZ7s3dALT60pveMbI3kcs7UOtDp14gKlyebUk9ejlg7acW+153Z oPfBCDEgRhQOIX+ZejkUx9YYjTBJC43e4lfmtvzzmccRB1Rl0AHErHGP8WlCALz8YStS jSAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0NNiCqwzESyAJCUAtzOveFlWcEoCPQvaoYU5oWya4UE=; b=uzxJv4rs5zI4v8qaxBXrz133CGOEw4hgWPG4qoKF37LkP6mjofqq+NnCjlxOKhmWf+ FpavC+KAsrQD65HFKBNP7XF2axKZFWTAbAxTjoUnQcDl2eIlqeb/6z1hvRobyxHk8+NO 2cfXx//nwKvAetUPlbpGy3Av5xrm5fL1XT7XeLLWgmETroMg9ziTfJG8yFLZ3wvofx0x ef7CKrFVtr6UOGJsw51SRHdLPxb/tPPLleXToMwgS7kfLv/NMkJiipECJWXGzbGTJwY+ 2OYgkQEbbjQxQCqz/czLCDLxSGkrgG5JeiGmW04Ua6qZFF/oa/9AtZ2gBzETP/drGFdr Y2iA== X-Gm-Message-State: AO0yUKXQL4kbGTvW8qMTzux2FJZ0ctv0aFW3DCtM5XisHyPtZJPRYG5u 24QlYrJeidovgbUrloTvrcpTIdmubQRe1V97 X-Google-Smtp-Source: AK7set/gX+d7qL2VYRm0mNT1mURMK3jqpTnNExhfErr1wouO0vmd1XoXrrDp0BwbdxbCN+7oo8RXZwzOeOx6nPe4 X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a17:903:1c8:b0:193:9ec:fc13 with SMTP id e8-20020a17090301c800b0019309ecfc13mr1942596plh.33.1675380757137; Thu, 02 Feb 2023 15:32:37 -0800 (PST) Date: Thu, 2 Feb 2023 23:32:29 +0000 In-Reply-To: <20230202233229.3895713-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230202233229.3895713-1-yosryahmed@google.com> X-Mailer: git-send-email 2.39.1.519.gcb327c4b5f-goog Message-ID: <20230202233229.3895713-3-yosryahmed@google.com> Subject: [RFC PATCH v1 2/2] mm: vmscan: ignore non-LRU-based reclaim in memcg reclaim From: Yosry Ahmed To: Alexander Viro , "Darrick J. Wong" , Christoph Lameter , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "Matthew Wilcox (Oracle)" , Miaohe Lin , David Hildenbrand , Johannes Weiner , Peter Xu , NeilBrown , Shakeel Butt , Michal Hocko Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org We keep track of different types of reclaimed pages through reclaim_state->reclaimed, and we add them to the reported number of reclaimed pages. For non-memcg reclaim, this makes sense. For memcg reclaim, we have no clue if those pages are charged to the memcg under reclaim. Slab pages are shared by different memcgs, so a freed slab page may have only been partially charged to the memcg under reclaim. The same goes for clean file pages from pruned inodes or xfs buffer pages, there is no way to link them to the memcg under reclaim. Stop reporting those freed pages as reclaimed pages during memcg reclaim. This should make the return value of writing to memory.reclaim, and may help reduce unnecessary reclaim retries during memcg charging. Generally, this should make the return value of try_to_free_mem_cgroup_pages() more accurate. In some limited cases (e.g. freed a slab page that was mostly charged to the memcg under reclaim), the return value of try_to_free_mem_cgroup_pages() can be underestimated, but this should be fine as it is mostly called in a retry loop. Signed-off-by: Yosry Ahmed --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 63a27d2f6f31..207998b16e5f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -6181,7 +6181,7 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) shrink_node_memcgs(pgdat, sc); - if (reclaim_state) { + if (reclaim_state && !cgroup_reclaim(sc)) { sc->nr_reclaimed += reclaim_state->reclaimed; reclaim_state->reclaimed = 0; }