Since the migratetype hygiene patches [0], the locking here is a bit more formalised, so write it down with an assert. [0] https://lore.kernel.org/lkml/20240320180429.678181-3-hannes@xxxxxxxxxxx/T/ Signed-off-by: Brendan Jackman <jackmanb@xxxxxxxxxx> --- include/linux/memory_hotplug.h | 1 + mm/memory_hotplug.c | 5 +++++ mm/page_alloc.c | 4 ++++ 3 files changed, 10 insertions(+) diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index eaac5ae8c05c8ee2f2868d5bc1b04d1f68235b3f..ff9511d9b9e6f775feeb4f897754878ac4c8cdb0 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -175,6 +175,7 @@ void put_online_mems(void); void mem_hotplug_begin(void); void mem_hotplug_done(void); +bool in_mem_hotplug(void); /* See kswapd_is_running() */ static inline void pgdat_kswapd_lock(pg_data_t *pgdat) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 16cf9e17077e359b98a69dc4bca48f4575b9a28c..2b9d1a6267c0872c433fafe8684dd4e2aa821f5f 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -267,6 +267,11 @@ void mem_hotplug_done(void) cpus_read_unlock(); } +bool in_mem_hotplug(void) +{ + return percpu_is_write_locked(&mem_hotplug_lock); +} + u64 max_mem_size = U64_MAX; /* add this memory to iomem resource */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 299c9f10bbcd2aa1d35ac6eb5131a2471da825d5..e0516d70835e20e54ff8e43f3aa884c7e36d929a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -417,6 +417,10 @@ void set_pfnblock_flags_mask(struct page *page, unsigned long flags, void set_pageblock_migratetype(struct page *page, int migratetype) { + lockdep_assert_once(system_state == SYSTEM_BOOTING || + in_mem_hotplug() || + lockdep_is_held(&page_zone(page)->lock)); + if (unlikely(page_group_by_mobility_disabled && migratetype < MIGRATE_PCPTYPES)) migratetype = MIGRATE_UNMOVABLE; --- base-commit: d58172d128acbafa2295aa17cc96e28260da9a86 change-id: 20250227-pageblock-lockdep-9628c48d7e08 Best regards, -- Brendan Jackman <jackmanb@xxxxxxxxxx>
