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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 BD560C4361B for ; Tue, 15 Dec 2020 13:36:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71E5D22482 for ; Tue, 15 Dec 2020 13:36:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728324AbgLONgF (ORCPT ); Tue, 15 Dec 2020 08:36:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:45814 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728283AbgLONgB (ORCPT ); Tue, 15 Dec 2020 08:36:01 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1608039314; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=E0ZZlFIFNjZLjI1zJKZsoEml0sOwnDtgK026kYKenBI=; b=Z6ZxxODUV2XHWmRmYCV1o9D/nJq+SiPOW/aVOWIkMz7l8JSXApKVfT7woLR4dunzRE3lHN bXNP2YJ/wA77wTuYlDWHXlsn7YrOnOYBxfsmB3r0/ill/VsLwPkkVG+GZK8GpOcIsm4WT6 EsTvSABPjTzw/lP1Dj2nyEqnl2U4TGA= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 632F9AF45; Tue, 15 Dec 2020 13:35:14 +0000 (UTC) Date: Tue, 15 Dec 2020 14:35:14 +0100 From: Michal Hocko To: Muchun Song Cc: gregkh@linuxfoundation.org, rafael@kernel.org, adobriyan@gmail.com, akpm@linux-foundation.org, hannes@cmpxchg.org, vdavydov.dev@gmail.com, hughd@google.com, shakeelb@google.com, guro@fb.com, samitolvanen@google.com, feng.tang@intel.com, neilb@suse.de, iamjoonsoo.kim@lge.com, rdunlap@infradead.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org Subject: Re: [PATCH v3 7/7] mm: memcontrol: make the slab calculation consistent Message-ID: <20201215133514.GP32193@dhcp22.suse.cz> References: <20201208041847.72122-1-songmuchun@bytedance.com> <20201208041847.72122-8-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201208041847.72122-8-songmuchun@bytedance.com> Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue 08-12-20 12:18:47, Muchun Song wrote: > Although the ratio of the slab is one, we also should read the ratio > from the related memory_stats instead of hard-coding. And the local > variable of size is already the value of slab_unreclaimable. So we > do not need to read again. > > We can drop the ratio in struct memory_stat. This can make the code > clean and simple. And get rid of the awkward mix of static and runtime > initialization of the memory_stats table. This changelog doesn't explain, what is the problem, why do we care and why the additional code is worthwile. > Signed-off-by: Muchun Song > --- > mm/memcontrol.c | 112 ++++++++++++++++++++++++++++++++++++-------------------- > 1 file changed, 73 insertions(+), 39 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index a40797a27f87..841ea37cc123 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1511,49 +1511,78 @@ static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) > > struct memory_stat { > const char *name; > - unsigned int ratio; > unsigned int idx; > }; > > static const struct memory_stat memory_stats[] = { > - { "anon", PAGE_SIZE, NR_ANON_MAPPED }, > - { "file", PAGE_SIZE, NR_FILE_PAGES }, > - { "kernel_stack", 1024, NR_KERNEL_STACK_KB }, > - { "pagetables", PAGE_SIZE, NR_PAGETABLE }, > - { "percpu", 1, MEMCG_PERCPU_B }, > - { "sock", PAGE_SIZE, MEMCG_SOCK }, > - { "shmem", PAGE_SIZE, NR_SHMEM }, > - { "file_mapped", PAGE_SIZE, NR_FILE_MAPPED }, > - { "file_dirty", PAGE_SIZE, NR_FILE_DIRTY }, > - { "file_writeback", PAGE_SIZE, NR_WRITEBACK }, > + { "anon", NR_ANON_MAPPED }, > + { "file", NR_FILE_PAGES }, > + { "kernel_stack", NR_KERNEL_STACK_KB }, > + { "pagetables", NR_PAGETABLE }, > + { "percpu", MEMCG_PERCPU_B }, > + { "sock", MEMCG_SOCK }, > + { "shmem", NR_SHMEM }, > + { "file_mapped", NR_FILE_MAPPED }, > + { "file_dirty", NR_FILE_DIRTY }, > + { "file_writeback", NR_WRITEBACK }, > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > - { "anon_thp", PAGE_SIZE, NR_ANON_THPS }, > - { "file_thp", PAGE_SIZE, NR_FILE_THPS }, > - { "shmem_thp", PAGE_SIZE, NR_SHMEM_THPS }, > + { "anon_thp", NR_ANON_THPS }, > + { "file_thp", NR_FILE_THPS }, > + { "shmem_thp", NR_SHMEM_THPS }, > #endif > - { "inactive_anon", PAGE_SIZE, NR_INACTIVE_ANON }, > - { "active_anon", PAGE_SIZE, NR_ACTIVE_ANON }, > - { "inactive_file", PAGE_SIZE, NR_INACTIVE_FILE }, > - { "active_file", PAGE_SIZE, NR_ACTIVE_FILE }, > - { "unevictable", PAGE_SIZE, NR_UNEVICTABLE }, > - > - /* > - * Note: The slab_reclaimable and slab_unreclaimable must be > - * together and slab_reclaimable must be in front. > - */ > - { "slab_reclaimable", 1, NR_SLAB_RECLAIMABLE_B }, > - { "slab_unreclaimable", 1, NR_SLAB_UNRECLAIMABLE_B }, > + { "inactive_anon", NR_INACTIVE_ANON }, > + { "active_anon", NR_ACTIVE_ANON }, > + { "inactive_file", NR_INACTIVE_FILE }, > + { "active_file", NR_ACTIVE_FILE }, > + { "unevictable", NR_UNEVICTABLE }, > + { "slab_reclaimable", NR_SLAB_RECLAIMABLE_B }, > + { "slab_unreclaimable", NR_SLAB_UNRECLAIMABLE_B }, > > /* The memory events */ > - { "workingset_refault_anon", 1, WORKINGSET_REFAULT_ANON }, > - { "workingset_refault_file", 1, WORKINGSET_REFAULT_FILE }, > - { "workingset_activate_anon", 1, WORKINGSET_ACTIVATE_ANON }, > - { "workingset_activate_file", 1, WORKINGSET_ACTIVATE_FILE }, > - { "workingset_restore_anon", 1, WORKINGSET_RESTORE_ANON }, > - { "workingset_restore_file", 1, WORKINGSET_RESTORE_FILE }, > - { "workingset_nodereclaim", 1, WORKINGSET_NODERECLAIM }, > + { "workingset_refault_anon", WORKINGSET_REFAULT_ANON }, > + { "workingset_refault_file", WORKINGSET_REFAULT_FILE }, > + { "workingset_activate_anon", WORKINGSET_ACTIVATE_ANON }, > + { "workingset_activate_file", WORKINGSET_ACTIVATE_FILE }, > + { "workingset_restore_anon", WORKINGSET_RESTORE_ANON }, > + { "workingset_restore_file", WORKINGSET_RESTORE_FILE }, > + { "workingset_nodereclaim", WORKINGSET_NODERECLAIM }, > }; > > +/* Translate stat items to the correct unit for memory.stat output */ > +static int memcg_page_state_unit(int item) > +{ > + int unit; > + > + switch (item) { > + case MEMCG_PERCPU_B: > + case NR_SLAB_RECLAIMABLE_B: > + case NR_SLAB_UNRECLAIMABLE_B: > + case WORKINGSET_REFAULT_ANON: > + case WORKINGSET_REFAULT_FILE: > + case WORKINGSET_ACTIVATE_ANON: > + case WORKINGSET_ACTIVATE_FILE: > + case WORKINGSET_RESTORE_ANON: > + case WORKINGSET_RESTORE_FILE: > + case WORKINGSET_NODERECLAIM: > + unit = 1; > + break; > + case NR_KERNEL_STACK_KB: > + unit = SZ_1K; > + break; > + default: > + unit = PAGE_SIZE; > + break; > + } > + > + return unit; > +} > + > +static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg, > + int item) > +{ > + return memcg_page_state(memcg, item) * memcg_page_state_unit(item); > +} > + > static char *memory_stat_format(struct mem_cgroup *memcg) > { > struct seq_buf s; > @@ -1577,13 +1606,12 @@ static char *memory_stat_format(struct mem_cgroup *memcg) > for (i = 0; i < ARRAY_SIZE(memory_stats); i++) { > u64 size; > > - size = memcg_page_state(memcg, memory_stats[i].idx); > - size *= memory_stats[i].ratio; > + size = memcg_page_state_output(memcg, memory_stats[i].idx); > seq_buf_printf(&s, "%s %llu\n", memory_stats[i].name, size); > > if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) { > - size = memcg_page_state(memcg, NR_SLAB_RECLAIMABLE_B) + > - memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE_B); > + size += memcg_page_state_output(memcg, > + NR_SLAB_RECLAIMABLE_B); > seq_buf_printf(&s, "slab %llu\n", size); > } > } > @@ -6377,6 +6405,12 @@ static int memory_stat_show(struct seq_file *m, void *v) > } > > #ifdef CONFIG_NUMA > +static inline unsigned long lruvec_page_state_output(struct lruvec *lruvec, > + int item) > +{ > + return lruvec_page_state(lruvec, item) * memcg_page_state_unit(item); > +} > + > static int memory_numa_stat_show(struct seq_file *m, void *v) > { > int i; > @@ -6394,8 +6428,8 @@ static int memory_numa_stat_show(struct seq_file *m, void *v) > struct lruvec *lruvec; > > lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); > - size = lruvec_page_state(lruvec, memory_stats[i].idx); > - size *= memory_stats[i].ratio; > + size = lruvec_page_state_output(lruvec, > + memory_stats[i].idx); > seq_printf(m, " N%d=%llu", nid, size); > } > seq_putc(m, '\n'); > -- > 2.11.0 -- Michal Hocko SUSE Labs