On Mon, 2010-11-29 at 11:53 +0900, KAMEZAWA Hiroyuki wrote: > On Fri, 26 Nov 2010 15:38:51 +0100 > Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote: > > > Make mmu_gather preemptible by using a small on stack list and use > > an option allocation to speed things up. > > > > Preemptible mmu_gather is desired in general and usable once > > i_mmap_lock becomes a mutex. Doing it before the mutex conversion > > saves us from having to rework the code by moving the mmu_gather > > bits inside the i_mmap_lock. > > > > Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > > Cc: David Miller <davem@xxxxxxxxxxxxx> > > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> > > Cc: Russell King <rmk@xxxxxxxxxxxxxxxx> > > Cc: Paul Mundt <lethal@xxxxxxxxxxxx> > > Cc: Jeff Dike <jdike@xxxxxxxxxxx> > > Cc: Tony Luck <tony.luck@xxxxxxxxx> > > Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> > > Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> > > Interesting, Hmm, how about using the 1st freed pages as tlb->pages > rathet than calling alloc_page() ? no benefits ? We could try that, but we need to be careful there, you need to wait till after the TLB invalidate and possibly an RCU period for the page-directory pages (sparc/powerpc). So doing an optimistic allocation before the TLB invalidate seems saner. Also, see patch 20. -- 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
