Re: [PATCH] sparseirq: Enable early irq_desc allocation.

[Ingo Molnar <mingo@elte.hu>]

* Paul Mundt <lethal@linux-sh.org> wrote:

> On Thu, May 21, 2009 at 01:26:26PM -0700, Yinghai Lu wrote:
> > can you check tip?
> > we change _cpu to node already.
> > 
> > also only sh have after_bootmem now.
> > arch/sh/mm/init.c:int after_bootmem = 0;
> > arch/sh/mm/init.c:      after_bootmem = 1;
> > arch/sh/mm/ioremap_64.c:        extern int after_bootmem;
> > arch/sh/mm/ioremap_64.c:        if (after_bootmem) {
> > include/linux/mm.h:extern int after_bootmem;
> > 
> > for x86 we have bootmem_state ...
> > arch/x86/include/asm/page_types.h:enum bootmem_state {
> > arch/x86/include/asm/page_types.h:extern enum bootmem_state bootmem_state;
> > arch/x86/kernel/setup.c:        bootmem_state = DURING_BOOTMEM;
> > arch/x86/mm/init.c:enum bootmem_state bootmem_state = BEFORE_BOOTMEM;
> > arch/x86/mm/init.c:     if (bootmem_state == BEFORE_BOOTMEM)
> > arch/x86/mm/init.c:     if (bootmem_state == BEFORE_BOOTMEM)
> > arch/x86/mm/init.c:     if (bootmem_state == BEFORE_BOOTMEM && !start) {
> > arch/x86/mm/init.c:     if (bootmem_state == BEFORE_BOOTMEM &&
> > arch/x86/mm/init.c:     if (bootmem_state == BEFORE_BOOTMEM)
> > 
> > Andrew,
> > do we need to move bootmem_state back to linux/mm.h?
> 
> No need, I just switched to slab_is_available() in the respin. Here is
> v2, against -tip:

thanks.

I'm a bit unhappy about allocators here (and this is not your 
fault). There's not two but _three_ states for allocation: bootmem, 
pagealloc, kmalloc. There is a (short) stage during bootup where 
kmalloc is not enabled yet and bootmem is already deactivated. If we 
ever use slab_is_available() in such a state it will blow up.

Fixing all this allocator bootstrapping mess we have in Linux is a 
lot larger project though.

	Ingo