On 11/05/2015 09:09 AM, Joonsoo Kim wrote: > On Wed, Nov 04, 2015 at 04:00:57PM +0100, Vlastimil Babka wrote: >> The information in /sys/kernel/debug/page_owner includes the migratetype >> declared during the page allocation via gfp_flags. This is also checked against >> the pageblock's migratetype, and reported as Fallback allocation if these two >> differ (although in fact fallback allocation is not the only reason why they >> can differ). >> >> However, the migratetype actually printed is the one of the pageblock, not of >> the page itself, so it's the same for all pages in the pageblock. This is >> apparently a bug, noticed when working on other page_owner improvements. Fixed. > > We can guess page migratetype through gfp_mask output although it isn't > easy task for now. But, there is no way to know pageblock migratetype. > I used this to know how memory is fragmented. Ah, I see. How bout just we print both migratetypes then and remove the "Fallback" part, which can be trivially deduced from them (and as I noted it's somewhat misleading anyway)? > Thanks. > >> >> Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> >> --- >> mm/page_owner.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/mm/page_owner.c b/mm/page_owner.c >> index 983c3a1..a9f16b8 100644 >> --- a/mm/page_owner.c >> +++ b/mm/page_owner.c >> @@ -113,7 +113,7 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, >> "PFN %lu Block %lu type %d %s Flags %s%s%s%s%s%s%s%s%s%s%s%s\n", >> pfn, >> pfn >> pageblock_order, >> - pageblock_mt, >> + page_mt, >> pageblock_mt != page_mt ? "Fallback" : " ", >> PageLocked(page) ? "K" : " ", >> PageError(page) ? "E" : " ", >> -- >> 2.6.2 >> >> -- >> 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> > -- 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>