[lkml]   [2013]   [Jul]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] mm: Save soft-dirty bits on swapped pages
On Wed, Jul 24, 2013 at 09:23:14AM -0700, Andy Lutomirski wrote:
> On Wed, Jul 24, 2013 at 9:08 AM, Cyrill Gorcunov <> wrote:
> > Andy Lutomirski reported that in case if a page with _PAGE_SOFT_DIRTY
> > bit set get swapped out, the bit is getting lost and no longer
> > available when pte read back.
> Potentially silly question (due to my completely lack of understanding
> of how swapping works in Linux): what about file-backed pages?
> (Arguably these would be best supported by filesystems instead of by
> the core vm, in which case it might make sense to drop soft-dirty
> support for these pages entirely.)

Hi Andy, if I understand you correctly "file-backed pages" are carried
in pte with _PAGE_FILE bit set and the swap soft-dirty bit won't be
used on them but _PAGE_SOFT_DIRTY will be set on write if only I've
not missed something obvious (Pavel?).

 \ /
  Last update: 2013-07-24 19:01    [W:0.078 / U:3.616 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site