lkml.org 
[lkml]   [2018]   [Jun]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH -mm -V3 03/21] mm, THP, swap: Support PMD swap mapping in swap_duplicate()
On Tue, Jun 12, 2018 at 11:15:28AM +0800, Huang, Ying wrote:
> "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.

Fair enough, I'll see about adding this along with the other patch I'm sending.

Daniel

\
 
 \ /
  Last update: 2018-06-12 14:06    [W:0.091 / U:5.732 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site