On Wed, Jul 22, 2015 at 02:29:08PM +0200, Vlastimil Babka wrote: > On 07/21/2015 02:53 PM, Vlastimil Babka wrote: > > The pair of get/set_freepage_migratetype() functions are used to cache > > pageblock migratetype for a page put on a pcplist, so that it does not have > > to be retrieved again when the page is put on a free list (e.g. when pcplists > > become full). Historically it was also assumed that the value is accurate for > > pages on freelists (as the functions' names unfortunately suggest), but that > > cannot be guaranteed without affecting various allocator fast paths. It is in > > fact not needed and all such uses have been removed. > > > > The last remaining (but pointless) usage related to pages of freelists is in > > move_freepages(), which this patch removes. > > I realized there's one more callsite that can be removed. Here's > whole updated patch due to different changelog and to cope with > context changed by the fixlet to patch 1/2. > > ------8<------ > From: Vlastimil Babka <vbabka@xxxxxxx> > Date: Thu, 2 Jul 2015 16:37:06 +0200 > Subject: mm: rename and move get/set_freepage_migratetype > > The pair of get/set_freepage_migratetype() functions are used to cache > pageblock migratetype for a page put on a pcplist, so that it does not have > to be retrieved again when the page is put on a free list (e.g. when pcplists > become full). Historically it was also assumed that the value is accurate for > pages on freelists (as the functions' names unfortunately suggest), but that > cannot be guaranteed without affecting various allocator fast paths. It is in > fact not needed and all such uses have been removed. > > The last two remaining (but pointless) usages related to pages of freelists > are removed by this patch: > - move_freepages() which operates on pages already on freelists > - __free_pages_ok() which puts a page directly to freelist, bypassing pcplists > > To prevent further confusion, rename the functions to > get/set_pcppage_migratetype() and expand their description. Since all the > users are now in mm/page_alloc.c, move the functions there from the shared > header. > > Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> > Acked-by: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > Cc: Minchan Kim <minchan@xxxxxxxxxx> > Cc: Michal Nazarewicz <mina86@xxxxxxxxxx> > Cc: Laura Abbott <lauraa@xxxxxxxxxxxxxx> > Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxx> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> -- 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