On Tue, 24 May 2011 06:51:01 +1000 Benjamin Herrenschmidt <b...@kernel.crashing.org> wrote:
> Is your linear mapping bolted ? If it is you may be able to cut out most > of the save/restore stuff (SRR0,1, ...) since with a normal walk you > won't take nested misses. It is bolted -- we ignore anything we can't map with 16 entries. The only semi-realistic case I can think of where we might bump into that (and thus want non-bolted memory), especially with more than negligible loss compared to the size of memory, is AMP with a non-zero start address where we have to stick with smaller pages due to alignment. Even so, 16 times the alignment of the start of RAM doesn't seem that unreasonable a limit. The 32-bit limit of 3 entries for lowmem is a bit more troublesome there. -Scott _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
