On Fri, 2010-04-09 at 13:35 +1000, Nick Piggin wrote: > On Thu, Apr 08, 2010 at 09:17:46PM +0200, Peter Zijlstra wrote: > > Index: linux-2.6/include/asm-generic/tlb.h > > =================================================================== > > --- linux-2.6.orig/include/asm-generic/tlb.h > > +++ linux-2.6/include/asm-generic/tlb.h > > @@ -27,6 +27,49 @@ > > #define tlb_fast_mode(tlb) 1 > > #endif > > > > +#ifdef HAVE_ARCH_RCU_TABLE_FREE > > +/* > > + * Semi RCU freeing of the page directories. > > + * > > + * This is needed by some architectures to implement gup_fast(). > > Really? I see the comment in the powerpc code, but powerpc was already > using RCU before gup_fast(), and AFAIKS it is indeed using it so that > it can handle faults by getting the linux pte with find_linux_pte ? Ah, see that is my ignorance of the powerpc mmu code, I've only been staring at this mmu_gather piece long enough to (hopefully) make it work. If there is indeed more to it, then yes, that needs documenting. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
