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| author | Vlastimil Babka <vbabka@suse.cz> | 2021-05-11 17:45:26 +0200 |
|---|---|---|
| committer | Vlastimil Babka <vbabka@suse.cz> | 2021-09-04 01:12:21 +0200 |
| commit | 4b1f449dedd2ff1eede4ced08a503e13c8d668ce (patch) | |
| tree | b62ea094b918c5c85a691a27d01ef9e328dce165 /mm | |
| parent | mm, slub: check new pages with restored irqs (diff) | |
| download | linux-4b1f449dedd2ff1eede4ced08a503e13c8d668ce.tar.xz linux-4b1f449dedd2ff1eede4ced08a503e13c8d668ce.zip | |
mm, slub: stop disabling irqs around get_partial()
The function get_partial() does not need to have irqs disabled as a whole. It's
sufficient to convert spin_lock operations to their irq saving/restoring
versions.
As a result, it's now possible to reach the page allocator from the slab
allocator without disabling and re-enabling interrupts on the way.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/slub.c | 22 |
1 files changed, 8 insertions, 14 deletions
diff --git a/mm/slub.c b/mm/slub.c index b5788040d92e..8433e50d2c8e 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2010,11 +2010,12 @@ static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags); * Try to allocate a partial slab from a specific node. */ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, - struct page **ret_page, gfp_t flags) + struct page **ret_page, gfp_t gfpflags) { struct page *page, *page2; void *object = NULL; unsigned int available = 0; + unsigned long flags; int objects; /* @@ -2026,11 +2027,11 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, if (!n || !n->nr_partial) return NULL; - spin_lock(&n->list_lock); + spin_lock_irqsave(&n->list_lock, flags); list_for_each_entry_safe(page, page2, &n->partial, slab_list) { void *t; - if (!pfmemalloc_match(page, flags)) + if (!pfmemalloc_match(page, gfpflags)) continue; t = acquire_slab(s, n, page, object == NULL, &objects); @@ -2051,7 +2052,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, break; } - spin_unlock(&n->list_lock); + spin_unlock_irqrestore(&n->list_lock, flags); return object; } @@ -2779,8 +2780,10 @@ new_slab: local_irq_restore(flags); goto reread_page; } - if (unlikely(!slub_percpu_partial(c))) + if (unlikely(!slub_percpu_partial(c))) { + local_irq_restore(flags); goto new_objects; /* stolen by an IRQ handler */ + } page = c->page = slub_percpu_partial(c); slub_set_percpu_partial(c, page); @@ -2789,18 +2792,9 @@ new_slab: goto redo; } - local_irq_save(flags); - if (unlikely(c->page)) { - local_irq_restore(flags); - goto reread_page; - } - new_objects: - lockdep_assert_irqs_disabled(); - freelist = get_partial(s, gfpflags, node, &page); - local_irq_restore(flags); if (freelist) goto check_new_page; |