From: Hugh Dickins <hugh@veritas.com>
Date: Wed, 19 Nov 2008 23:36:37 +0000 (-0800)
Subject: vmscan: let GFP_NOFS go to swap again
X-Git-Tag: v2.6.28-rc6~26
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=63eb6b93ce725e4c5f38fc85dd703d49465b03cb;p=pandora-kernel.git

vmscan: let GFP_NOFS go to swap again

In the past, GFP_NOFS (but of course not GFP_NOIO) was allowed to reclaim
by writing to swap.  That got partially broken in 2.6.23, when may_enter_fs
initialization was moved up before the allocation of swap, so its
PageSwapCache test was failing the first time around,

Fix it by setting may_enter_fs when add_to_swap() succeeds with
__GFP_IO.  In fact, check __GFP_IO before calling add_to_swap():
allocating swap we're not ready to use just increases disk seeking.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

Reading git-diff-tree failed