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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD3A2C38142 for ; Wed, 1 Feb 2023 00:45:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231831AbjBAApC (ORCPT ); Tue, 31 Jan 2023 19:45:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231723AbjBAApA (ORCPT ); Tue, 31 Jan 2023 19:45:00 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01B274F87F for ; Tue, 31 Jan 2023 16:44:59 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 94E2D6174D for ; Wed, 1 Feb 2023 00:44:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EE46FC433EF; Wed, 1 Feb 2023 00:44:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1675212298; bh=jpHk3roOtM1T6jz80GIHPJYxg3QrGYwq2FAa0FZ0Nbs=; h=Date:To:From:Subject:From; b=d2qqOyXKVMy2EGCJQBSNHrOhwwGhJ5Z0FbzFz8cMxJrVYcn+i4c+YWJOq/NI834GF w3MBwC7Wt+GuLlAvtix4ihNFsY6Wz40lKyUKx+2CNv5+YoquWluXfAxx1Xh9ERdbW3 0Bo70kNLw7tRtgqjHA4qj7IpmTmM53eXdtZH6vQM= Date: Tue, 31 Jan 2023 16:44:57 -0800 To: mm-commits@vger.kernel.org, yosryahmed@google.com, ying.huang@intel.com, yang.shi@linux.alibaba.com, weixugc@google.com, tj@kernel.org, songmuchun@bytedance.com, shakeelb@google.com, roman.gushchin@linux.dev, lizefan.x@bytedance.com, hannes@cmpxchg.org, corbet@lwn.net, bagasdotme@gmail.com, almasrymina@google.com, mhocko@suse.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-hotfixes-stable] revert-mm-add-nodes=-arg-to-memoryreclaim.patch removed from -mm tree Message-Id: <20230201004457.EE46FC433EF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: Revert "mm: add nodes= arg to memory.reclaim" has been removed from the -mm tree. Its filename was revert-mm-add-nodes=-arg-to-memoryreclaim.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Michal Hocko Subject: Revert "mm: add nodes= arg to memory.reclaim" Date: Fri, 16 Dec 2022 10:46:33 +0100 This reverts commit 12a5d3955227b0d7e04fb793ccceeb2a1dd275c5. Although it is recognized that a finer grained pro-active reclaim is something we need and want the semantic of this implementation is really ambiguous. In a follow up discussion it became clear that there are two essential usecases here. One is to use memory.reclaim to pro-actively reclaim memory and expectation is that the requested and reported amount of memory is uncharged from the memcg. Another usecase focuses on pro-active demotion when the memory is merely shuffled around to demotion targets while the overall charged memory stays unchanged. The current implementation considers demoted pages as reclaimed and that break both usecases. [1] has tried to address the reporting part but there are more issues with that summarized in [2] and follow up emails. Let's revert the nodemask based extension of the memcg pro-active reclaim for now until we settle with a more robust semantic. [1] http://lkml.kernel.org/r/http://lkml.kernel.org/r/20221206023406.3182800-1-almasrymina@google.com [2] http://lkml.kernel.org/r/Y5bsmpCyeryu3Zz1@dhcp22.suse.cz Link: https://lkml.kernel.org/r/Y5xASNe1x8cusiTx@dhcp22.suse.cz Fixes: 12a5d3955227b0d ("mm: add nodes= arg to memory.reclaim") Signed-off-by: Michal Hocko Cc: Bagas Sanjaya Cc: Huang Ying Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Mina Almasry Cc: Muchun Song Cc: Roman Gushchin Cc: Shakeel Butt Cc: Tejun Heo Cc: Wei Xu Cc: Yang Shi Cc: Yosry Ahmed Cc: zefan li Signed-off-by: Andrew Morton --- Documentation/admin-guide/cgroup-v2.rst | 15 +--- include/linux/swap.h | 3 mm/memcontrol.c | 67 ++++------------------ mm/vmscan.c | 4 - 4 files changed, 21 insertions(+), 68 deletions(-) --- a/Documentation/admin-guide/cgroup-v2.rst~revert-mm-add-nodes=-arg-to-memoryreclaim +++ a/Documentation/admin-guide/cgroup-v2.rst @@ -1245,13 +1245,17 @@ PAGE_SIZE multiple when read back. This is a simple interface to trigger memory reclaim in the target cgroup. - This file accepts a string which contains the number of bytes to - reclaim. + This file accepts a single key, the number of bytes to reclaim. + No nested keys are currently supported. Example:: echo "1G" > memory.reclaim + The interface can be later extended with nested keys to + configure the reclaim behavior. For example, specify the + type of memory to reclaim from (anon, file, ..). + Please note that the kernel can over or under reclaim from the target cgroup. If less bytes are reclaimed than the specified amount, -EAGAIN is returned. @@ -1263,13 +1267,6 @@ PAGE_SIZE multiple when read back. This means that the networking layer will not adapt based on reclaim induced by memory.reclaim. - This file also allows the user to specify the nodes to reclaim from, - via the 'nodes=' key, for example:: - - echo "1G nodes=0,1" > memory.reclaim - - The above instructs the kernel to reclaim memory from nodes 0,1. - memory.peak A read-only single value file which exists on non-root cgroups. --- a/include/linux/swap.h~revert-mm-add-nodes=-arg-to-memoryreclaim +++ a/include/linux/swap.h @@ -418,8 +418,7 @@ extern unsigned long try_to_free_pages(s extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, unsigned long nr_pages, gfp_t gfp_mask, - unsigned int reclaim_options, - nodemask_t *nodemask); + unsigned int reclaim_options); extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem, gfp_t gfp_mask, bool noswap, pg_data_t *pgdat, --- a/mm/memcontrol.c~revert-mm-add-nodes=-arg-to-memoryreclaim +++ a/mm/memcontrol.c @@ -63,7 +63,6 @@ #include #include #include -#include #include "internal.h" #include #include @@ -2393,8 +2392,7 @@ static unsigned long reclaim_high(struct psi_memstall_enter(&pflags); nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, - MEMCG_RECLAIM_MAY_SWAP, - NULL); + MEMCG_RECLAIM_MAY_SWAP); psi_memstall_leave(&pflags); } while ((memcg = parent_mem_cgroup(memcg)) && !mem_cgroup_is_root(memcg)); @@ -2685,8 +2683,7 @@ retry: psi_memstall_enter(&pflags); nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, - gfp_mask, reclaim_options, - NULL); + gfp_mask, reclaim_options); psi_memstall_leave(&pflags); if (mem_cgroup_margin(mem_over_limit) >= nr_pages) @@ -3506,8 +3503,7 @@ static int mem_cgroup_resize_max(struct } if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, - memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP, - NULL)) { + memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP)) { ret = -EBUSY; break; } @@ -3618,8 +3614,7 @@ static int mem_cgroup_force_empty(struct return -EINTR; if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, - MEMCG_RECLAIM_MAY_SWAP, - NULL)) + MEMCG_RECLAIM_MAY_SWAP)) nr_retries--; } @@ -6429,8 +6424,7 @@ static ssize_t memory_high_write(struct } reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high, - GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP, - NULL); + GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP); if (!reclaimed && !nr_retries--) break; @@ -6479,8 +6473,7 @@ static ssize_t memory_max_write(struct k if (nr_reclaims) { if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, - GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP, - NULL)) + GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP)) nr_reclaims--; continue; } @@ -6603,54 +6596,21 @@ static ssize_t memory_oom_group_write(st return nbytes; } -enum { - MEMORY_RECLAIM_NODES = 0, - MEMORY_RECLAIM_NULL, -}; - -static const match_table_t if_tokens = { - { MEMORY_RECLAIM_NODES, "nodes=%s" }, - { MEMORY_RECLAIM_NULL, NULL }, -}; - static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); unsigned int nr_retries = MAX_RECLAIM_RETRIES; unsigned long nr_to_reclaim, nr_reclaimed = 0; - unsigned int reclaim_options = MEMCG_RECLAIM_MAY_SWAP | - MEMCG_RECLAIM_PROACTIVE; - char *old_buf, *start; - substring_t args[MAX_OPT_ARGS]; - int token; - char value[256]; - nodemask_t nodemask = NODE_MASK_ALL; - - buf = strstrip(buf); - - old_buf = buf; - nr_to_reclaim = memparse(buf, &buf) / PAGE_SIZE; - if (buf == old_buf) - return -EINVAL; + unsigned int reclaim_options; + int err; buf = strstrip(buf); + err = page_counter_memparse(buf, "", &nr_to_reclaim); + if (err) + return err; - while ((start = strsep(&buf, " ")) != NULL) { - if (!strlen(start)) - continue; - token = match_token(start, if_tokens, args); - match_strlcpy(value, args, sizeof(value)); - switch (token) { - case MEMORY_RECLAIM_NODES: - if (nodelist_parse(value, nodemask) < 0) - return -EINVAL; - break; - default: - return -EINVAL; - } - } - + reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE; while (nr_reclaimed < nr_to_reclaim) { unsigned long reclaimed; @@ -6667,8 +6627,7 @@ static ssize_t memory_reclaim(struct ker reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_to_reclaim - nr_reclaimed, - GFP_KERNEL, reclaim_options, - &nodemask); + GFP_KERNEL, reclaim_options); if (!reclaimed && !nr_retries--) return -EAGAIN; --- a/mm/vmscan.c~revert-mm-add-nodes=-arg-to-memoryreclaim +++ a/mm/vmscan.c @@ -6754,8 +6754,7 @@ unsigned long mem_cgroup_shrink_node(str unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, unsigned long nr_pages, gfp_t gfp_mask, - unsigned int reclaim_options, - nodemask_t *nodemask) + unsigned int reclaim_options) { unsigned long nr_reclaimed; unsigned int noreclaim_flag; @@ -6770,7 +6769,6 @@ unsigned long try_to_free_mem_cgroup_pag .may_unmap = 1, .may_swap = !!(reclaim_options & MEMCG_RECLAIM_MAY_SWAP), .proactive = !!(reclaim_options & MEMCG_RECLAIM_PROACTIVE), - .nodemask = nodemask, }; /* * Traverse the ZONELIST_FALLBACK zonelist of the current node to put _ Patches currently in -mm which might be from mhocko@suse.com are