memcg: when do_swap's do_wp_page fails

Don't uncharge when do_swap_page's call to do_wp_page fails: the page which
was charged for is there in the pagetable, and will be correctly uncharged
when that area is unmapped - it was only its COWing which failed.

And while we're here, remove earlier XXX comment: yes, OR in do_wp_page's
return value (maybe VM_FAULT_WRITE) with do_swap_page's there; but if it
fails, mask out success bits, which might confuse some arches e.g.  sparc.

Signed-off-by: Hugh Dickins <[email protected]>
Cc: David Rientjes <[email protected]>
Acked-by: Balbir Singh <[email protected]>
Acked-by: KAMEZAWA Hiroyuki <[email protected]>
Cc: Hirokazu Takahashi <[email protected]>
Cc: YAMAMOTO Takashi <[email protected]>
Cc: Paul Menage <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions