Re: [PATCH] alloc_percpu() fails to allocate percpu data
From: Christoph Lameter
Date: Wed Feb 27 2008 - 16:57:32 EST
On Wed, 27 Feb 2008, Andrew Morton wrote:
> On Wed, 27 Feb 2008 11:59:32 -0800 (PST)
> Christoph Lameter <clameter@xxxxxxx> wrote:
>
> > Any decision made on what to do about this one? Mike or I can
> > repost the per cpu allocator against mm? The fix by Eric could be used
> > in the interim for 2.6.24?
> >
>
> I suppose I'll merge Eric's patch when I've tested it fully (well, as fully
> as I test stuff).
Urgh. You too?
> It'd be nice to get that cache_line_size()/L1_CACHE_BYTES/L1_CACHE_ALIGN()
> mess sorted out. If it's a mess - I _think_ it is?
Well I tried it when slub went first in and it did not go well. The issue
is that x86 detects the cache line size on bootup. Thus cache_line_size().
Most of the other arch have compile time cache line sizes. Thus
L1_CACHE_BYTES. So L1_CACHE_BYTES is the maximum value that
cache_line_size() can take.
What I was attempting to do is to make x86 have one compile time cache
line size L1_CACHE_BYTES. That raised objections because space was wasted.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/