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 C471BD2ECEF for ; Mon, 19 Jan 2026 23:04:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 36C836B0330; Mon, 19 Jan 2026 18:04:18 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 353D76B0332; Mon, 19 Jan 2026 18:04:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2601E6B0333; Mon, 19 Jan 2026 18:04:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 1254C6B0330 for ; Mon, 19 Jan 2026 18:04:18 -0500 (EST) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id CD25FC177C for ; Mon, 19 Jan 2026 23:04:17 +0000 (UTC) X-FDA: 84350243754.30.61CE059 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf14.hostedemail.com (Postfix) with ESMTP id 0BC71100009 for ; Mon, 19 Jan 2026 23:04:15 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=oYhem+Ry; spf=pass (imf14.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1768863856; 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=OgbObs8HDdumlKaDxCQZI2KxkSHb7dglw2VWFF79KHc=; b=7RqgoiILrevjisjL9idNKwcropuFh/GjpVFS1iQelttbeq1kN9iTNhje5HdSe5LAtZ5viE glT2f9DtarUy9nrzxmpdxEjCyWMum2gqvqHbIt038BUbQ8aNaJNGFlrFiErXtwhfefsWhF MnRApwqdKX8GwctojkTOzAacAUlHXyw= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=oYhem+Ry; spf=pass (imf14.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1768863856; a=rsa-sha256; cv=none; b=f5YhRFHvwHBdC4uLouwAHL03NCPWCzYekvS9eWj6rwTOY2Pnj3jTLdkGPUJmo6wKMAXhjI vZTYlci7s6nb7jj3wdc41kvtgr7FJvvboDeco9+H5+2TsiPAe1Keevod9DthFcUA1lU2kG x5lDSn4YYnzN26dxb8gH5jmsvf80T4M= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 16E8440210; Mon, 19 Jan 2026 23:04:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D026BC116C6; Mon, 19 Jan 2026 23:04:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768863854; bh=rfLKWCy9vJo0cdwgW26hFt2Hmw6jpwEGhVTR8rbPNG0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oYhem+RyIfPYbRq/FfuQqbLgtWgy8BpIVjnZIFIo2pyBjNu0tkitvJixH2VAC5iwL 0udZb3Nwm9Nm9mnEfvtHLW9oTj17v3gePhwKqKsuwG2spWtGT7wrjMglu7Jk7xwwVL qgc0gO5oasN5SIWAvQ+fmSdW5X/8qWWN/6b89nNhT8qBhxDZLcl0dhrwWMDIQKhrbL 4k0sEibe6agRVrTRCbUTDZod92Sk3LXFSBCuK4MfajLCooB3qJFV8miYoiSDHNq1rg rRJf65xLWtvgrRdbaPTINUhuOO9OWGtADn303tSQQFRZaQP/O2FnwV9COpZS1oFNGo 4HRrRgQ99HmKA== From: "David Hildenbrand (Red Hat)" To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, Broadcom internal kernel review list , linux-doc@vger.kernel.org, virtualization@lists.linux.dev, "David Hildenbrand (Red Hat)" , Andrew Morton , Oscar Salvador , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonathan Corbet , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Arnd Bergmann , Greg Kroah-Hartman , Jerrin Shaji George , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , =?UTF-8?q?Eugenio=20P=C3=A9rez?= , Zi Yan Subject: [PATCH v3 22/24] mm: rename CONFIG_BALLOON_COMPACTION to CONFIG_BALLOON_MIGRATION Date: Tue, 20 Jan 2026 00:01:30 +0100 Message-ID: <20260119230133.3551867-23-david@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260119230133.3551867-1-david@kernel.org> References: <20260119230133.3551867-1-david@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: ac8itizj3qrrfinfpxd7fynxxukracrg X-Rspam-User: X-Rspamd-Queue-Id: 0BC71100009 X-Rspamd-Server: rspam08 X-HE-Tag: 1768863855-151863 X-HE-Meta: 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 +36gei0X RNh5cm23pOPIGeXkRCyNd/pKA5k0RY5V24khYInMkLDu8l2c7Uv0BP3D/u5UfhOUy7yzF61IFkq+mgBPhBdmVa0Fto1m+/yLW79BEso7SEzRjwAP1Ujy0ns/dkxLdBcA71xCsa6KPiOZyZvynXcnyQ/8eH9N+C5Ap0XRcG/wtTgMw15Lt1G8cFHXL+ZJFUGvMnJHN46to2fPeN4/T9p7IsHcPXlHdaJ/QASOBx0acTib3Ykr3A5fy6T8CnI3sLDBoXGF3qimNZbFPssKtOrQ9vBKKu5UB9XeFbM0dmQTZLEE7f8LCraRz+UKCDeGq/Pusudd3ycfVYpP2JOk= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: While compaction depends on migration, the other direction is not the case. So let's make it clearer that this is all about migration of balloon pages. Adjust all comments/docs in the core to talk about "migration" instead of "compaction". While at it add some "/* CONFIG_BALLOON_MIGRATION */". Reviewed-by: Lorenzo Stoakes Acked-by: Michael S. Tsirkin Signed-off-by: David Hildenbrand (Red Hat) --- Documentation/admin-guide/mm/memory-hotplug.rst | 8 ++++---- arch/powerpc/platforms/pseries/cmm.c | 8 ++++---- drivers/misc/vmw_balloon.c | 8 ++++---- drivers/virtio/virtio_balloon.c | 6 +++--- include/linux/balloon.h | 12 ++++++------ include/linux/vm_event_item.h | 4 ++-- mm/Kconfig | 4 ++-- mm/balloon.c | 10 +++++----- mm/memory_hotplug.c | 4 ++-- mm/migrate.c | 2 +- mm/vmstat.c | 4 ++-- 11 files changed, 35 insertions(+), 35 deletions(-) diff --git a/Documentation/admin-guide/mm/memory-hotplug.rst b/Documentation/admin-guide/mm/memory-hotplug.rst index 6581558fd0d7a..0207f87251421 100644 --- a/Documentation/admin-guide/mm/memory-hotplug.rst +++ b/Documentation/admin-guide/mm/memory-hotplug.rst @@ -603,11 +603,11 @@ ZONE_MOVABLE, especially when fine-tuning zone ratios: memory for metadata and page tables in the direct map; having a lot of offline memory blocks is not a typical case, though. -- Memory ballooning without balloon compaction is incompatible with - ZONE_MOVABLE. Only some implementations, such as virtio-balloon and - pseries CMM, fully support balloon compaction. +- Memory ballooning without support for balloon memory migration is incompatible + with ZONE_MOVABLE. Only some implementations, such as virtio-balloon and + pseries CMM, fully support balloon memory migration. - Further, the CONFIG_BALLOON_COMPACTION kernel configuration option might be + Further, the CONFIG_BALLOON_MIGRATION kernel configuration option might be disabled. In that case, balloon inflation will only perform unmovable allocations and silently create a zone imbalance, usually triggered by inflation requests from the hypervisor. diff --git a/arch/powerpc/platforms/pseries/cmm.c b/arch/powerpc/platforms/pseries/cmm.c index 7a3c4922685ab..8d83df12430f2 100644 --- a/arch/powerpc/platforms/pseries/cmm.c +++ b/arch/powerpc/platforms/pseries/cmm.c @@ -494,7 +494,7 @@ static struct notifier_block cmm_mem_nb = { .priority = CMM_MEM_HOTPLUG_PRI }; -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION static int cmm_migratepage(struct balloon_dev_info *b_dev_info, struct page *newpage, struct page *page, enum migrate_mode mode) @@ -520,10 +520,10 @@ static int cmm_migratepage(struct balloon_dev_info *b_dev_info, plpar_page_set_active(page); return 0; } -#else /* CONFIG_BALLOON_COMPACTION */ +#else /* CONFIG_BALLOON_MIGRATION */ int cmm_migratepage(struct balloon_dev_info *b_dev_info, struct page *newpage, struct page *page, enum migrate_mode mode); -#endif /* CONFIG_BALLOON_COMPACTION */ +#endif /* CONFIG_BALLOON_MIGRATION */ /** * cmm_init - Module initialization @@ -540,7 +540,7 @@ static int cmm_init(void) balloon_devinfo_init(&b_dev_info); b_dev_info.adjust_managed_page_count = true; - if (IS_ENABLED(CONFIG_BALLOON_COMPACTION)) + if (IS_ENABLED(CONFIG_BALLOON_MIGRATION)) b_dev_info.migratepage = cmm_migratepage; rc = register_oom_notifier(&cmm_oom_nb); diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c index 7fd3f709108c2..216a163959684 100644 --- a/drivers/misc/vmw_balloon.c +++ b/drivers/misc/vmw_balloon.c @@ -1719,7 +1719,7 @@ static inline void vmballoon_debugfs_exit(struct vmballoon *b) #endif /* CONFIG_DEBUG_FS */ -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION /** * vmballoon_migratepage() - migrates a balloon page. * @b_dev_info: balloon device information descriptor. @@ -1803,11 +1803,11 @@ static int vmballoon_migratepage(struct balloon_dev_info *b_dev_info, up_read(&b->conf_sem); return ret; } -#else /* CONFIG_BALLOON_COMPACTION */ +#else /* CONFIG_BALLOON_MIGRATION */ int vmballoon_migratepage(struct balloon_dev_info *b_dev_info, struct page *newpage, struct page *page, enum migrate_mode mode); -#endif /* CONFIG_BALLOON_COMPACTION */ +#endif /* CONFIG_BALLOON_MIGRATION */ static int __init vmballoon_init(void) { @@ -1827,7 +1827,7 @@ static int __init vmballoon_init(void) return error; balloon_devinfo_init(&balloon.b_dev_info); - if (IS_ENABLED(CONFIG_BALLOON_COMPACTION)) + if (IS_ENABLED(CONFIG_BALLOON_MIGRATION)) balloon.b_dev_info.migratepage = vmballoon_migratepage; INIT_LIST_HEAD(&balloon.huge_pages); diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index de8041c3285a1..4e549abe59ff1 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -802,7 +802,7 @@ static void report_free_page_func(struct work_struct *work) } } -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION /* * virtballoon_migratepage - perform the balloon page migration on behalf of * a compaction thread. (called under page lock) @@ -851,7 +851,7 @@ static int virtballoon_migratepage(struct balloon_dev_info *vb_dev_info, mutex_unlock(&vb->balloon_lock); return 0; } -#endif /* CONFIG_BALLOON_COMPACTION */ +#endif /* CONFIG_BALLOON_MIGRATION */ static unsigned long shrink_free_pages(struct virtio_balloon *vb, unsigned long pages_to_free) @@ -948,7 +948,7 @@ static int virtballoon_probe(struct virtio_device *vdev) if (!virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) vb->vb_dev_info.adjust_managed_page_count = true; -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION vb->vb_dev_info.migratepage = virtballoon_migratepage; #endif if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { diff --git a/include/linux/balloon.h b/include/linux/balloon.h index 82585542300d6..ca5b15150f425 100644 --- a/include/linux/balloon.h +++ b/include/linux/balloon.h @@ -22,9 +22,9 @@ * * As the page isolation scanning step a compaction thread does is a lockless * procedure (from a page standpoint), it might bring some racy situations while - * performing balloon page compaction. In order to sort out these racy scenarios - * and safely perform balloon's page compaction and migration we must, always, - * ensure following these simple rules: + * performing balloon page migration. In order to sort out these racy scenarios + * and safely perform balloon's page migration we must, always, ensure following + * these simple rules: * * i. Inflation/deflation must set/clear page->private under the * balloon_pages_lock @@ -45,10 +45,10 @@ /* * Balloon device information descriptor. - * This struct is used to allow the common balloon compaction interface + * This struct is used to allow the common balloon page migration interface * procedures to find the proper balloon device holding memory pages they'll - * have to cope for page compaction / migration, as well as it serves the - * balloon driver as a page book-keeper for its registered balloon devices. + * have to cope for page migration, as well as it serves the balloon driver as + * a page book-keeper for its registered balloon devices. */ struct balloon_dev_info { unsigned long isolated_pages; /* # of isolated pages for migration */ diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index 92f80b4d69a6d..fca34d3473b6b 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -125,9 +125,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, #ifdef CONFIG_MEMORY_BALLOON BALLOON_INFLATE, BALLOON_DEFLATE, -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION BALLOON_MIGRATE, -#endif +#endif /* CONFIG_BALLOON_MIGRATION */ #endif #ifdef CONFIG_DEBUG_TLBFLUSH NR_TLB_REMOTE_FLUSH, /* cpu tried to flush others' tlbs */ diff --git a/mm/Kconfig b/mm/Kconfig index 0d13c1b36e1c1..460a148d5b71a 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -597,8 +597,8 @@ config MEMORY_BALLOON bool # -# support for memory balloon compaction -config BALLOON_COMPACTION +# support for memory balloon page migration +config BALLOON_MIGRATION bool "Allow for balloon memory migration" default y depends on MIGRATION && MEMORY_BALLOON diff --git a/mm/balloon.c b/mm/balloon.c index 25e2a1e71eba9..834f86c3c116d 100644 --- a/mm/balloon.c +++ b/mm/balloon.c @@ -34,7 +34,7 @@ static void balloon_page_insert(struct balloon_dev_info *balloon, { lockdep_assert_held(&balloon_pages_lock); __SetPageOffline(page); - if (IS_ENABLED(CONFIG_BALLOON_COMPACTION)) { + if (IS_ENABLED(CONFIG_BALLOON_MIGRATION)) { SetPageMovableOps(page); set_page_private(page, (unsigned long)balloon); } @@ -51,7 +51,7 @@ static void balloon_page_insert(struct balloon_dev_info *balloon, static void balloon_page_finalize(struct page *page) { lockdep_assert_held(&balloon_pages_lock); - if (IS_ENABLED(CONFIG_BALLOON_COMPACTION)) + if (IS_ENABLED(CONFIG_BALLOON_MIGRATION)) set_page_private(page, 0); /* PageOffline is sticky until the page is freed to the buddy. */ } @@ -153,7 +153,7 @@ struct page *balloon_page_alloc(void) { gfp_t gfp_flags = __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; - if (IS_ENABLED(CONFIG_BALLOON_COMPACTION)) + if (IS_ENABLED(CONFIG_BALLOON_MIGRATION)) gfp_flags |= GFP_HIGHUSER_MOVABLE; else gfp_flags |= GFP_HIGHUSER; @@ -232,7 +232,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) } EXPORT_SYMBOL_GPL(balloon_page_dequeue); -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION static bool balloon_page_isolate(struct page *page, isolate_mode_t mode) @@ -342,4 +342,4 @@ static int __init balloon_init(void) } core_initcall(balloon_init); -#endif /* CONFIG_BALLOON_COMPACTION */ +#endif /* CONFIG_BALLOON_MIGRATION */ diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 389989a28abe0..bc805029da517 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -946,8 +946,8 @@ static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn * We rely on "present pages" instead of "managed pages", as the latter is * highly unreliable and dynamic in virtualized environments, and does not * consider boot time allocations. For example, memory ballooning adjusts the - * managed pages when inflating/deflating the balloon, and balloon compaction - * can even migrate inflated pages between zones. + * managed pages when inflating/deflating the balloon, and balloon page + * migration can even migrate inflated pages between zones. * * Using "present pages" is better but some things to keep in mind are: * diff --git a/mm/migrate.c b/mm/migrate.c index 4750a2ba15fef..1bf2cf8c44dd4 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -88,7 +88,7 @@ static const struct movable_operations *page_movable_ops(struct page *page) * back to the buddy. */ if (PageOffline(page)) - /* Only balloon compaction sets PageOffline pages movable. */ + /* Only balloon page migration sets PageOffline pages movable. */ return offline_movable_ops; if (PageZsmalloc(page)) return zsmalloc_movable_ops; diff --git a/mm/vmstat.c b/mm/vmstat.c index 6ae8891c9693e..e96a344ab5974 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1422,9 +1422,9 @@ const char * const vmstat_text[] = { #ifdef CONFIG_MEMORY_BALLOON [I(BALLOON_INFLATE)] = "balloon_inflate", [I(BALLOON_DEFLATE)] = "balloon_deflate", -#ifdef CONFIG_BALLOON_COMPACTION +#ifdef CONFIG_BALLOON_MIGRATION [I(BALLOON_MIGRATE)] = "balloon_migrate", -#endif +#endif /* CONFIG_BALLOON_MIGRATION */ #endif /* CONFIG_MEMORY_BALLOON */ #ifdef CONFIG_DEBUG_TLBFLUSH [I(NR_TLB_REMOTE_FLUSH)] = "nr_tlb_remote_flush", -- 2.52.0