Messages in this thread | | | Subject | Re: slab: setup allocators earlier in the boot sequence | From | Pekka Enberg <> | Date | Fri, 12 Jun 2009 17:04:17 +0300 |
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Hi Ben,
On Sat, 2009-06-13 at 00:02 +1000, Benjamin Herrenschmidt wrote: > On Fri, 2009-06-12 at 16:54 +0300, Pekka Enberg wrote: > > Hi Christoph, > > > > On Fri, 2009-06-12 at 09:49 -0400, Christoph Lameter wrote: > > > Best thing to do is to recognize the fact that we are still in early boot > > > in the allocators. Derived allocators (such as slab and vmalloc) mask bits > > > using GFP_RECLAIM_MASK and when doing allocations through the page > > > allocator. You could make GFP_RECLAIM_MASK a variable. During boot > > > __GFP_WAIT would not be set in GFP_RECLAIM_MASK. > > > > Ben's patch does something like that and I have patches that do that > > floating around too. > > > > The problem here is that it's not enough that we make GFP_RECLAIM_MASK a > > variable. There are various _debugging checks_ that happen much earlier > > than that. We need to mask out those too which adds overhead to > > kmalloc() fastpath, for example. > > Hrm... I though I stuck my masking before the lockdep tests but maybe I > missed some...
Your patch is fine but what Christoph suggested is not (at least the way I understood it).
Pekka
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