Re: [bg-linux] [PATCH 5/7] [RFC] force 32-byte aligned kmallocs
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2011-05-20 02:13:55
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2011-05-20 02:13:55
Also in:
lkml
On Fri, 2011-05-20 at 12:08 +1000, Benjamin Herrenschmidt wrote:
On Thu, 2011-05-19 at 20:32 -0500, Kazutomo Yoshii wrote:quoted
Actually DMA sends invalidate requests to the snoop unit(L2 level). BGP SoC is a bit different from other 4xx base.Well, some other 44x also have a snooping L2 (more or less), but L1 is usually the problem.
Hrm... looking at the doco you pointed me to, it looks like the L1 -is- coherent, it gets snoop kills from the L2. Ok so we do need to make this non-coherent cache stuff a runtime option (well, we need that for 440+476 too anyways so may as well do it now). As for the alignment of kmalloc, it looks like a hack that should be done in the torus code itself. Cheers, Ben.