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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 v2 21/23] mm: rename CONFIG_BALLOON_COMPACTION to CONFIG_BALLOON_MIGRATION Date: Thu, 15 Jan 2026 10:20:11 +0100 Message-ID: <20260115092015.3928975-22-david@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115092015.3928975-1-david@kernel.org> References: <20260115092015.3928975-1-david@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: C6A6C1C0004 X-Stat-Signature: qy4cr3jhjtiyaxg39my6ybsqot343omq X-Rspam-User: X-HE-Tag: 1768468969-332957 X-HE-Meta: U2FsdGVkX18/coa3NWsOGh0wCHgJaJZYawXQ7YWpSJibxBi9QP6mlKPfSdm2z9oAremBk0RFUw/xIGJWuXFi136+8KEYyuFQmy15bgos1/LEriGXbBdODcneVp4/zw4XR91Az8TT99VJpANFWOY6tr8QnJ7V/RK2fPOkGRi2s/Gfv0vAdFWny+jFXl7F/LmKmw0rwff8iUA2MwNjQ2/gqjnkezMGdJIFmjNfuuQ3d7J7zV/azZ1Qc0zfVcKZabA86wlHG5mOkkZnKyQek/DDN/OQly8JBo1tMQwkxTx8DoPWFn8duGxmp76KFyTqpuBbMdBNF1y3HQhNdvdrmfafY2kpFIVM7+xidxETbunFdq/EwovOt3dlTiRQ/M2rwHNKJf61rHlMnlozoiwMfUblfuLnvqElSeNP/Py6Ws3glnN9sz+5x1bslspt1H/GbUiYrQCvVWCVD7Q76HS6mDLaucOasAs3k46ckd3mGtIDamW7S7YzVfXIop3RFKsN87ee4CY5XEnTB9wFCV6P5x3QueQpbCm5DjFACstDDv35qBhkOJ1MGXhSgR+i4HrVVZj84bz35NSmNqEyjINMQavaYI3XK99gUg7f5un+HLGLUaxSqFK9qPpInBG3GMgLkT8XjVxOxmm4g6Db2dWkM6FQmZy/bHy76tpi6i9LFUjTKmA66vUzMni7F08oo9m9KeMbye0pIPaq++0SqyLQV42yC9SLzZqKt3shuBLzWFRrHlaIWabkH3imSk+XsYHEfEVhhr5nUgrKkUzwj1pidJ7ThAMedQBZy/GmoW2W8osv5IDb5bKuOOYSJQcMwMipdln1mtLDER/aGd0tgYFW2zrBP8n9jcVkeAkTT9/cPujpltBnBbSBFkDUNrU5crYIjLr7P9g6B9tF7KxuKipjanCt+imtPsVvRlmgpOYvQM1dG5m4sjyAZhRO4XQGaPz84Vp2bMTgt1jkyUH6ki72MAi K7u+U9kj rI3rrbshJuYEPoTlX0Rctrr4MR6GRJ102JNHjBKWG5X9Ty51+fAewiQQGSChKBZ0S5rKsOrSe+sRTqlVutZ5HNGACDYTSFnVcVQAIvHqCQedU0OirDHwxUmxPP0JGj2/+5wWc2lrM/Hm9OpG7e3bxQJK/SaT2D14Mj3FUqe0138J5lmOZDJBNsUQylveJqR13SyIQDgFafXS33ggEf2ymlsQGG9G69wXdznOmtPTYabMYaQt9l3kzkC+/BOegMVGSJykw8C+b7XjSPMIfTDwKqGteaA== 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 */". 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 | 2 +- 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, 30 insertions(+), 30 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..e8da95ca4ad48 100644 --- a/include/linux/balloon.h +++ b/include/linux/balloon.h @@ -45,7 +45,7 @@ /* * 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. 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 5734dae81e318..8a21c6b9a7f0a 100644 --- a/mm/balloon.c +++ b/mm/balloon.c @@ -34,7 +34,7 @@ static inline 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 inline void balloon_page_insert(struct balloon_dev_info *balloon, static inline 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) @@ -340,4 +340,4 @@ 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