[PATCH v5 28/35] mm, slab: make flush_slab() possible to call with irqs enabled
From: Vlastimil Babka <hidden>
Date: 2021-08-23 15:00:59
Also in:
lkml
Subsystem:
memory management, slab allocator, the rest · Maintainers:
Andrew Morton, Vlastimil Babka, Harry Yoo, Linus Torvalds
Currently flush_slab() is always called with disabled IRQs if it's needed, but the following patches will change that, so add a parameter to control IRQ disabling within the function, which only protects the kmem_cache_cpu manipulation and not the call to deactivate_slab() which doesn't need it. Signed-off-by: Vlastimil Babka <redacted> --- mm/slub.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index ddcaddc5e801..bb7e05543738 100644
--- a/mm/slub.c
+++ b/mm/slub.c@@ -2480,16 +2480,28 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) #endif /* CONFIG_SLUB_CPU_PARTIAL */ } -static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) +static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c, + bool lock) { - void *freelist = c->freelist; - struct page *page = c->page; + unsigned long flags; + void *freelist; + struct page *page; + + if (lock) + local_irq_save(flags); + + freelist = c->freelist; + page = c->page; c->page = NULL; c->freelist = NULL; c->tid = next_tid(c->tid); - deactivate_slab(s, page, freelist); + if (lock) + local_irq_restore(flags); + + if (page) + deactivate_slab(s, page, freelist); stat(s, CPUSLAB_FLUSH); }
@@ -2499,7 +2511,7 @@ static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); if (c->page) - flush_slab(s, c); + flush_slab(s, c, false); unfreeze_partials_cpu(s, c); }
@@ -2515,7 +2527,7 @@ static void flush_cpu_slab(void *d) struct kmem_cache_cpu *c = this_cpu_ptr(s->cpu_slab); if (c->page) - flush_slab(s, c); + flush_slab(s, c, false); unfreeze_partials(s); }
--
2.32.0