On Wed, May 29, 2013 at 01:56:13PM +0100, Vineet Gupta wrote: > zap_pte_range loops from @addr to @end. In the middle, if it runs out of > batching slots, TLB entries needs to be flushed for @start to @interim, > NOT @interim to @end. > > Since ARC port doesn't use page free batching I can't test it myself but > this seems like the right thing to do. > Observed this when working on a fix for the issue at thread: > http://www.spinics.net/lists/linux-arch/msg21736.html > > Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxx> > Cc: Hugh Dickins <hughd@xxxxxxxxxx> > Cc: Rik van Riel <riel@xxxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Cc: linux-mm@xxxxxxxxx > Cc: linux-arch@xxxxxxxxxxxxxxx <linux-arch@xxxxxxxxxxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: Max Filippov <jcmvbkbc@xxxxxxxxx> > --- > mm/memory.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/mm/memory.c b/mm/memory.c > index 6dc1882..d9d5fd9 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -1110,6 +1110,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, > spinlock_t *ptl; > pte_t *start_pte; > pte_t *pte; > + unsigned long range_start = addr; > > again: > init_rss_vec(rss); > @@ -1215,12 +1216,14 @@ again: > force_flush = 0; > > #ifdef HAVE_GENERIC_MMU_GATHER > - tlb->start = addr; > - tlb->end = end; > + tlb->start = range_start; > + tlb->end = addr; > #endif > tlb_flush_mmu(tlb); > - if (addr != end) > + if (addr != end) { > + range_start = addr; > goto again; > + } > } Isn't this code only run if force_flush != 0? force_flush is set to !__tlb_remove_page() and this function always returns 1 on (generic TLB) UP since tlb_fast_mode() is 1. There is no batching on UP with the generic TLB code. -- Catalin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>