Messages in this thread | | | Date | Mon, 09 Feb 2009 00:44:03 -0800 | From | Yinghai Lu <> | Subject | Re: [PATCH] irq: optimize init_kstat_irqs/init_copy_kstat_irqs |
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Ingo Molnar wrote: > * Andrew Morton <akpm@linux-foundation.org> wrote: > >> On Mon, 9 Feb 2009 09:11:24 +0100 Ingo Molnar <mingo@elte.hu> wrote: >> >>> * Andrew Morton <akpm@linux-foundation.org> wrote: >>> >>>> On Sat, 7 Feb 2009 01:01:03 -0800 Yinghai Lu <yinghai@kernel.org> wrote: >>>> >>>>> add kzalloc_node_safe()? >>>> I cannot find that function. >>> His suggestion is to provide that allocator variant. >>> >> Oh. >> >> It isn't possible to write a kzalloc_node_safe(GFP_ATOMIC). Or at >> least, we've never worked out a way. >> >> Maybe I'm confused again. > > Indeed - duh - more morning tea needed. > > Yinghai, why are those allocations GFP_ATOMIC to begin with? These: > > earth4:~/tip> grep GFP_ATOMIC kernel/irq/*.c > kernel/irq/handle.c: ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs), GFP_ATOMIC, node); > kernel/irq/handle.c: desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node); > kernel/irq/manage.c: action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC); > > Should all be GFP_KERNEL. Wherever they are within a spinlocked section the code > should be restructured. All descriptor data structures should be preallocated at > __setup_irq() time. If we ever need to allocate dynamically later on, in the middle > of some difficult codepath that's a structure bug in the code.
ok.
> > and this one: > > kernel/irq/numa_migrate.c: desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node); > > should fail the migration silently if GFP_ATOMIC returns NULL. it will reuse the old one.
YH
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