On Mon, Nov 22, 2010 at 02:21:09PM -0800, Andrew Morton wrote: > On Sun, 21 Nov 2010 23:30:24 +0900 > Minchan Kim <minchan.kim@xxxxxxxxx> wrote: > > > Now zap_pte_range alwayas promotes pages which are pte_young && > > !VM_SequentialReadHint(vma). But in case of calling MADV_DONTNEED, > > it's unnecessary since the page wouldn't use any more. > > > > If the page is sharred by other processes and it's real working set > > This patch doesn't actually do anything. It passes variable `promote' > all the way down to unmap_vmas(), but unmap_vmas() doesn't use that new > variable. > > Have a comment fixlet: > > --- a/mm/memory.c~mm-prevent-promotion-of-page-in-madvise_dontneed-fix > +++ a/mm/memory.c > @@ -1075,7 +1075,7 @@ static unsigned long unmap_page_range(st > * @end_addr: virtual address at which to end unmapping > * @nr_accounted: Place number of unmapped pages in vm-accountable vma's here > * @details: details of nonlinear truncation or shared cache invalidation > - * @promote: whether pages inclued vma would be promoted or not > + * @promote: whether pages included in the vma should be promoted or not > * > * Returns the end address of the unmapping (restart addr if interrupted). > * > _ > > Also, I'd suggest that we avoid introducing the term "promote". Promote also has special meaning for huge pages. Demoting or promoting a page refers to changing its size. The same applies to the other patch - s/demote/deactive/ s/promote/activate/ . Currently this is no confusion within the VM but when Andrea's THP patches are merged, it'll become an issue. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>