diff options
| author | Hugh Dickins <hugh@veritas.com> | 2008-03-04 14:29:08 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-03-04 16:35:15 -0800 |
| commit | 7e924aafa4b03ff71de34af8553d9a1ebc86c071 (patch) | |
| tree | 21735b7369ede27f34c41184b0a686020b80e2c6 /mm/shmem.c | |
| parent | 9442ec9df40d952b0de185ae5638a74970388e01 (diff) | |
| download | lwn-7e924aafa4b03ff71de34af8553d9a1ebc86c071.tar.gz lwn-7e924aafa4b03ff71de34af8553d9a1ebc86c071.zip | |
memcg: mem_cgroup_charge never NULL
My memcgroup patch to fix hang with shmem/tmpfs added NULL page handling to
mem_cgroup_charge_common. It seemed convenient at the time, but hard to
justify now: there's a perfectly appropriate swappage to charge and uncharge
instead, this is not on any hot path through shmem_getpage, and no performance
hit was observed from the slight extra overhead.
So revert that NULL page handling from mem_cgroup_charge_common; and make it
clearer by bringing page_cgroup_assign_new_page_cgroup into its body - that
was a helper I found more of a hindrance to understanding.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: David Rientjes <rientjes@google.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hirokazu Takahashi <taka@valinux.co.jp>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/shmem.c')
| -rw-r--r-- | mm/shmem.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 90b576cbc06e..3372bc579e89 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1370,14 +1370,17 @@ repeat: shmem_swp_unmap(entry); spin_unlock(&info->lock); unlock_page(swappage); - page_cache_release(swappage); if (error == -ENOMEM) { /* allow reclaim from this memory cgroup */ - error = mem_cgroup_cache_charge(NULL, + error = mem_cgroup_cache_charge(swappage, current->mm, gfp & ~__GFP_HIGHMEM); - if (error) + if (error) { + page_cache_release(swappage); goto failed; + } + mem_cgroup_uncharge_page(swappage); } + page_cache_release(swappage); goto repeat; } } else if (sgp == SGP_READ && !filepage) { |