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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7A467C4452B for ; Thu, 23 Jul 2026 03:25:08 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2C97E6B00C5; Wed, 22 Jul 2026 23:25:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2A1206B00C6; Wed, 22 Jul 2026 23:25:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1B70A6B00C7; Wed, 22 Jul 2026 23:25:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id C66E96B00C5 for ; Wed, 22 Jul 2026 23:25:06 -0400 (EDT) Received: from smtpin13.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 1E5911C083D for ; Thu, 23 Jul 2026 03:25:06 +0000 (UTC) X-FDA: 85018600212.13.3DEA272 Received: from out-180.mta0.migadu.com (out-180.mta0.migadu.com [91.218.175.180]) by imf11.hostedemail.com (Postfix) with ESMTP id 5958640003 for ; Thu, 23 Jul 2026 03:25:04 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=gykCpbqN; spf=pass (imf11.hostedemail.com: domain of ridong.chen@linux.dev designates 91.218.175.180 as permitted sender) smtp.mailfrom=ridong.chen@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1784777104; b=magck33aLboAmtlFkFAP5bBNeCRV+K2UrjigBSbzpi/hpf+2qZqndtF1U83ssRuGTAHnaQ vXcPhNYg5J3gV6vS7uAolJrE9kflwKp03/RLa5qC+TkFB7UoKHElKTYRDeb6OqDo9UNEl8 cZuc7jKaBMl/dLuO1+Y8U39BBHdCtQA= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=gykCpbqN; spf=pass (imf11.hostedemail.com: domain of ridong.chen@linux.dev designates 91.218.175.180 as permitted sender) smtp.mailfrom=ridong.chen@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1784777104; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=t47mgjsy2KATKhTslu3AP/jd8ifMIeJbuWQDv9xr0N8=; b=Whx8YYqgD5XzInpUntwJZJRER617xq1KG8DP4cZfRgq4bb1P847R6Gp9T1+niHHVJ0xvxV C1CIQ9ygtl13HVfIWCp1CajfL4YqhWNzTq3/c3w0OI5DrAC6o6pNIoM5cXSp0xdlJgyQvN /V8M6XvbwZ9F8IH6unRofYv9PcYwLMg= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1784777102; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=t47mgjsy2KATKhTslu3AP/jd8ifMIeJbuWQDv9xr0N8=; b=gykCpbqNsx4BiZ36b+UTQGtY+ftHVgYOSP8swT3LMfmfhdE0M4m4FkiWOu7gTEKoKrv/Nr wKPC82RRw9bJ0XZNiur+JqNtAzBkesSdIgYJ8hUSDhf01VdoqTAAGATmEKcNmkMz4rouDE iIuriFNDDi41duWXaSkBR/sMyyPEHJ4= From: Ridong To: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Andrew Morton , Chris Li , Kairui Song Cc: Muchun Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Youngjun Park , David Hildenbrand , Qi Zheng , Lorenzo Stoakes , Axel Rasmussen , Yuanchu Xie , Wei Xu , Davidlohr Bueso , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Song Hu , Ridong Chen , Ridong Chen Subject: [PATCH -v4 1/2] memcg: move mem_cgroup_swappiness and vm_swappiness to mm/swap.h Date: Thu, 23 Jul 2026 11:24:33 +0800 Message-Id: <20260723032434.2016749-2-ridong.chen@linux.dev> In-Reply-To: <20260723032434.2016749-1-ridong.chen@linux.dev> References: <20260723032434.2016749-1-ridong.chen@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 5958640003 X-Stat-Signature: 9mxpcmp9mhkbsmqtiqownkrehsibpi6w X-Rspam-User: X-HE-Tag: 1784777104-24676 X-HE-Meta: U2FsdGVkX19E+l2DEmEY/SkYRG1V2sdPZuI08NyUgPbA8EAj2ca32aEpO4+CJvxGrcAsNB5yTYNzjEslZaCnTffOrLGD6gcMCu76+jC7+B1uZ0EuYHj2X2CT7XfOcxiyIo+iJV2wt0sPODYOx7Sh1cwLLiHtjRqktUXUtOfiAF+jVBfdov1qGkw6FLS64q/XTyWmnEk4EXE2gVC7ezv5dz5KoW/DM8ZSQDTfEOiJyQkrAW+XFN6mAEo5VGfy++hFa79iAAiTHkeulcOlZQ+VuBN9DtOpPX7qr7g6px7wF5BJX8bRgkU4SRz2XkPKB5jfGW6G2Y6P2bvWdINWKBtKdD5hqkuxOMCxgHZ+majW1BnRQ5nzP74mlhhJrc+Bza8/LiCcgjEsqCnNaH0gDxRi55C2kf6mKO2vK1Bs1Rykf1C1BwfgHBw2jYgvZ00b7Gl4gkNMzbIOMMuXICRIDY46YeGSss7Jfn97iJP7IqXBxQvCDTBAx54t3k5+q34R+aLh0U1yBWi/8oVDbmzsZwe5cG13BcSu7wPrjVAlg3VZyuGsinf5kLJ1i81T+XElwL/FoN8c/QhLg/ynB1HFI2xq4M7eJ1DR7FYDLP8WNyWb/eUumIfgTiU1PLOCO72hWqGzvOVvzFLR6HvjO7QGzs5Qpojoq6jbBsy0LDiNkjKCLPSWqiYWZxHd0hnPMgEiShWA5utkKPmpDEZgofUT+3s80z6vhcolzX1iIjGPJowIltCfPewbb8/Em/3IbOqtYZeMazWbQbu3EjYHDHGXXLJsTnpnQOj/Nm521Af/s+yasJ3aDvm664HvhfSiyxk68UOT6BQs5j2TB/L89RZxkeRACFCFF9YXS6DF8jCMN67vKGteaMO4pE+hs1V1r2D8AqOq+WzQ0y/BdrpcvbwzHd/QKV4UX6LPWCCVT6oJZ6MPhO8xiZniZh09XdDbtmKyACmhHbxpwfQIkiWPWRYtNN2 BdvMyzuN ZLL38A2xC4ASGJmil6yBKjNRcAe5Q8s6/czhrqXY22gY6jZHZmuiiZMW7QeiAxvkoBbjtqUtkgFWP/B9Tqc1DjqYVqypsi0RRqWKhbmLpebftAyHKwvtQUEs+AxcgwL2BeiUsJgBTsHMJrqiifc2IXF0qVmz511bJA60UP/ecIP/PF+W90bcCIjONfvweGAHkjYgDjM9rnTXWDTh+QtsBReeHTu/6WjzzDplyfWvuCA6l26LyiB6GY1/LkOUyjkq5k48WUTuMcqhOVnacSG92FN71+At7nlU4iXQq5AX8Zvnx/y3hvDv3hoTbQ4BBf1SakeO0r3aa+qUZVIiRgF/jEhUSbZ+CDSouAZeU9H8uXGBAfPo= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Ridong Chen The per-memcg swappiness knob is v1-only; v2 always uses global vm_swappiness and ignores the per-cgroup field. Both mem_cgroup_swappiness() and vm_swappiness are only used within mm/ (memcontrol.c, memcontrol-v1.c, vmscan.c), so move them out of the public include/linux/swap.h into the mm-private mm/swap.h. This keeps unrelated declarations out of include/linux/swap.h. Guard memcg->swappiness with CONFIG_MEMCG_V1 as well, so v2-only kernels drop the unused field. No functional change for v1; v2-only kernels drop the unused field. Acked-by: Johannes Weiner Reviewed-by: Barry Song Reviewed-by: Song Hu Signed-off-by: Ridong Chen --- include/linux/memcontrol.h | 4 ++-- include/linux/swap.h | 19 ------------------- mm/memcontrol.c | 4 ++-- mm/swap.h | 13 +++++++++++++ 4 files changed, 17 insertions(+), 23 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 957260677678..e7a794dfb40e 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -239,8 +239,6 @@ struct mem_cgroup { */ bool oom_group; - int swappiness; - /* memory.events and memory.events.local */ struct cgroup_file events_file; struct cgroup_file events_local_file; @@ -318,6 +316,8 @@ struct mem_cgroup { /* List of events which userspace want to receive */ struct list_head event_list; spinlock_t event_list_lock; + + int swappiness; #endif /* CONFIG_MEMCG_V1 */ struct mem_cgroup_per_node *nodeinfo[]; diff --git a/include/linux/swap.h b/include/linux/swap.h index 0544b2ec4c56..45f301d73e2a 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -309,7 +309,6 @@ static inline bool lru_cache_disabled(void) } extern unsigned long shrink_all_memory(unsigned long nr_pages); -extern int vm_swappiness; long remove_mapping(struct address_space *mapping, struct folio *folio); #if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA) @@ -473,25 +472,7 @@ static inline int add_swap_extent(struct swap_info_struct *sis, } #endif /* CONFIG_SWAP */ #ifdef CONFIG_MEMCG -static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg) -{ - /* Cgroup2 doesn't have per-cgroup swappiness */ - if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) - return READ_ONCE(vm_swappiness); - - /* root ? */ - if (mem_cgroup_disabled() || mem_cgroup_is_root(memcg)) - return READ_ONCE(vm_swappiness); - - return READ_ONCE(memcg->swappiness); -} - void lru_reparent_memcg(struct mem_cgroup *memcg, struct mem_cgroup *parent, int nid); -#else -static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg) -{ - return READ_ONCE(vm_swappiness); -} #endif #if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 8319ad8c5c23..6864b76456fb 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -63,6 +63,7 @@ #include #include #include "internal.h" +#include "swap.h" #include "swap_table.h" #include #include @@ -4176,11 +4177,10 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) #endif page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); if (parent) { - WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); - page_counter_init(&memcg->memory, &parent->memory, memcg_on_dfl); page_counter_init(&memcg->swap, &parent->swap, false); #ifdef CONFIG_MEMCG_V1 + WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); memcg->memory.track_failcnt = !memcg_on_dfl; WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable)); page_counter_init(&memcg->kmem, &parent->kmem, false); diff --git a/mm/swap.h b/mm/swap.h index abd26588abd2..d077e5893a42 100644 --- a/mm/swap.h +++ b/mm/swap.h @@ -4,6 +4,7 @@ #include /* for atomic_long_t */ #include /* for PAGE_SHIFT */ +#include /* for mem_cgroup_swappiness() */ struct mempolicy; struct swap_iocb; @@ -99,6 +100,18 @@ struct swap_ops { void (*submit_read)(struct swap_io_ctx *ctx); }; +extern int vm_swappiness; + +static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg) +{ +#ifdef CONFIG_MEMCG_V1 + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && + !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg)) + return READ_ONCE(memcg->swappiness); +#endif + return READ_ONCE(vm_swappiness); +} + #ifdef CONFIG_SWAP #include /* for swp_offset */ #include /* for bio_end_io_t */ -- 2.34.1