Messages in this thread | | | From | "Huang\, Ying" <> | Subject | Re: [PATCH -mm -V3 03/21] mm, THP, swap: Support PMD swap mapping in swap_duplicate() | Date | Tue, 12 Jun 2018 11:15:28 +0800 |
| |
"Huang, Ying" <ying.huang@intel.com> writes: >> On Wed, May 23, 2018 at 04:26:07PM +0800, Huang, Ying wrote: >>> @@ -3516,11 +3512,39 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) >> >> Two comments about this part of __swap_duplicate as long as you're moving it to >> another function: >> >> } else if (count || has_cache) { >> >> if ((count & ~COUNT_CONTINUED) < SWAP_MAP_MAX) /* #1 */ >> count += usage; >> else if ((count & ~COUNT_CONTINUED) > SWAP_MAP_MAX) /* #2 */ >> err = -EINVAL; >> >> #1: __swap_duplicate_locked might use >> >> VM_BUG_ON(usage != SWAP_HAS_CACHE && usage != 1); >> >> to document the unstated assumption that usage is 1 (otherwise count could >> overflow). > > Sounds good. Will do this.
Found usage parameter of __swap_duplicate() could be SWAP_MAP_SHMEM too. We can improve the parameter checking. But that appears not belong to this series.
Best Regards, Huang, Ying
| |