[PATCH v6 21/33] mm, slub: move irq control into unfreeze_partials()
From: Vlastimil Babka <hidden>
Date: 2021-09-04 10:52:08
Also in:
lkml
Subsystem:
memory management, slab allocator, the rest · Maintainers:
Andrew Morton, Vlastimil Babka, Harry Yoo, Linus Torvalds
unfreeze_partials() can be optimized so that it doesn't need irqs disabled for the whole time. As the first step, move irq control into the function and remove it from the put_cpu_partial() caller. Signed-off-by: Vlastimil Babka <redacted> --- mm/slub.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index cb12a077c61c..1c4bd45d66a1 100644
--- a/mm/slub.c
+++ b/mm/slub.c@@ -2350,9 +2350,8 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page, /* * Unfreeze all the cpu partial slabs. * - * This function must be called with interrupts disabled - * for the cpu using c (or some other guarantee must be there - * to guarantee no concurrent accesses). + * This function must be called with preemption or migration + * disabled with c local to the cpu. */ static void unfreeze_partials(struct kmem_cache *s, struct kmem_cache_cpu *c)
@@ -2360,6 +2359,9 @@ static void unfreeze_partials(struct kmem_cache *s, #ifdef CONFIG_SLUB_CPU_PARTIAL struct kmem_cache_node *n = NULL, *n2 = NULL; struct page *page, *discard_page = NULL; + unsigned long flags; + + local_irq_save(flags); while ((page = slub_percpu_partial(c))) { struct page new;
@@ -2412,6 +2414,8 @@ static void unfreeze_partials(struct kmem_cache *s, discard_slab(s, page); stat(s, FREE_SLAB); } + + local_irq_restore(flags); #endif /* CONFIG_SLUB_CPU_PARTIAL */ }
@@ -2439,14 +2443,11 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) pobjects = oldpage->pobjects; pages = oldpage->pages; if (drain && pobjects > slub_cpu_partial(s)) { - unsigned long flags; /* * partial array is full. Move the existing * set to the per node partial list. */ - local_irq_save(flags); unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); - local_irq_restore(flags); oldpage = NULL; pobjects = 0; pages = 0;
--
2.33.0