From 4ef3f5a32051def596b2d445462a1dccda7af600 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Tue, 23 Aug 2022 19:03:59 +0200 Subject: [PATCH] mm/slub: convert object_map_lock to non-raw spinlock The only remaining user of object_map_lock is list_slab_objects(). Obtaining the lock there used to happen under slab_lock() which implied disabling irqs on PREEMPT_RT, thus it's a raw_spinlock. With the slab_lock() removed, we can convert it to a normal spinlock. Also remove the get_map()/put_map() wrappers as list_slab_objects() became their only remaining user. Signed-off-by: Vlastimil Babka Acked-by: David Rientjes Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Sebastian Andrzej Siewior --- mm/slub.c | 36 ++++++------------------------------ 1 file changed, 6 insertions(+), 30 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 37234e6..e0759b5 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -565,7 +565,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct slab *slab, #ifdef CONFIG_SLUB_DEBUG static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)]; -static DEFINE_RAW_SPINLOCK(object_map_lock); +static DEFINE_SPINLOCK(object_map_lock); static void __fill_map(unsigned long *obj_map, struct kmem_cache *s, struct slab *slab) @@ -599,30 +599,6 @@ static bool slab_add_kunit_errors(void) static inline bool slab_add_kunit_errors(void) { return false; } #endif -/* - * Determine a map of objects in use in a slab. - * - * Node listlock must be held to guarantee that the slab does - * not vanish from under us. - */ -static unsigned long *get_map(struct kmem_cache *s, struct slab *slab) - __acquires(&object_map_lock) -{ - VM_BUG_ON(!irqs_disabled()); - - raw_spin_lock(&object_map_lock); - - __fill_map(object_map, s, slab); - - return object_map; -} - -static void put_map(unsigned long *map) __releases(&object_map_lock) -{ - VM_BUG_ON(map != object_map); - raw_spin_unlock(&object_map_lock); -} - static inline unsigned int size_from_object(struct kmem_cache *s) { if (s->flags & SLAB_RED_ZONE) @@ -4368,21 +4344,21 @@ static void list_slab_objects(struct kmem_cache *s, struct slab *slab, { #ifdef CONFIG_SLUB_DEBUG void *addr = slab_address(slab); - unsigned long flags; - unsigned long *map; void *p; slab_err(s, slab, text, s->name); - map = get_map(s, slab); + spin_lock(&object_map_lock); + __fill_map(object_map, s, slab); + for_each_object(p, s, addr, slab->objects) { - if (!test_bit(__obj_to_index(s, addr, p), map)) { + if (!test_bit(__obj_to_index(s, addr, p), object_map)) { pr_err("Object 0x%p @offset=%tu\n", p, p - addr); print_tracking(s, p); } } - put_map(map); + spin_unlock(&object_map_lock); #endif } -- 2.7.4