From: Thomas Gleixner Date: Wed, 9 Jan 2013 12:08:15 +0100 Subject: [PATCH 082/351] slub: Enable irqs for __GFP_WAIT Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=1be9be5f873d2a5d5743064f8e1a0c80d7ecc737 SYSTEM_RUNNING might be too late for enabling interrupts. Allocations with GFP_WAIT can happen before that. So use this as an indicator. Signed-off-by: Thomas Gleixner --- mm/slub.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/slub.c b/mm/slub.c index 1f32f64254a7..197bab70a05d 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1597,10 +1597,17 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) void *start, *p; int idx, order; bool shuffle; + bool enableirqs = false; flags &= gfp_allowed_mask; if (gfpflags_allow_blocking(flags)) + enableirqs = true; +#ifdef CONFIG_PREEMPT_RT_FULL + if (system_state > SYSTEM_BOOTING) + enableirqs = true; +#endif + if (enableirqs) local_irq_enable(); flags |= s->allocflags; @@ -1659,7 +1666,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) page->frozen = 1; out: - if (gfpflags_allow_blocking(flags)) + if (enableirqs) local_irq_disable(); if (!page) return NULL;