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No functional change. >> >> ... >> >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -6235,16 +6235,13 @@ static void calculate_totalreserve_pages(void) >> unsigned long managed_pages = zone_managed_pages(zone); >> >> /* Find valid and maximum lowmem_reserve in the zone */ >> - for (j = i; j < MAX_NR_ZONES; j++) { >> - if (zone->lowmem_reserve[j] > max) >> - max = zone->lowmem_reserve[j]; >> - } >> + for (j = i; j < MAX_NR_ZONES; j++) >> + max = max(max, zone->lowmem_reserve[j]); >> >> /* we treat the high watermark as reserved pages. */ >> max += high_wmark_pages(zone); >> >> - if (max > managed_pages) >> - max = managed_pages; >> + max = min_t(unsigned long, max, managed_pages); >> > > Use of max_t/min_t is usually a sign that we messed up the type choices > somewhere. > > In this case, I'd say that zone.lowmem_reserve[] should have been > ulong. Oh well. It was, but then changed into long because in __zone_watermark_ok() it is compared to can-be-negative free_pages (see commit 3484b2de9499). Maybe it is better to revert that change and convert ulong lowmem_reserve to long in __zone_watermark_ok() for the comparison. +Mel, for his opinion on it, since he made the change in 3484b2de9499. -- Best Regards, Yan, Zi