diff options
| author | Mel Gorman | 2012-08-01 01:44:26 +0200 |
|---|---|---|
| committer | Linus Torvalds | 2012-08-01 03:42:46 +0200 |
| commit | b4b9e3558508980fc0cd161a545ffb55a1f13ee9 (patch) | |
| tree | abb2ab54f4b201b1cbdaf181ec16912c3dd889eb /net/core/sock.c | |
| parent | netvm: propagate page->pfmemalloc from skb_alloc_page to skb (diff) | |
| download | kernel-qcow2-linux-b4b9e3558508980fc0cd161a545ffb55a1f13ee9.tar.gz kernel-qcow2-linux-b4b9e3558508980fc0cd161a545ffb55a1f13ee9.tar.xz kernel-qcow2-linux-b4b9e3558508980fc0cd161a545ffb55a1f13ee9.zip | |
netvm: set PF_MEMALLOC as appropriate during SKB processing
In order to make sure pfmemalloc packets receive all memory needed to
proceed, ensure processing of pfmemalloc SKBs happens under PF_MEMALLOC.
This is limited to a subset of protocols that are expected to be used for
writing to swap. Taps are not allowed to use PF_MEMALLOC as these are
expected to communicate with userspace processes which could be paged out.
[a.p.zijlstra@chello.nl: Ideas taken from various patches]
[jslaby@suse.cz: Lock imbalance fix]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'net/core/sock.c')
| -rw-r--r-- | net/core/sock.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index c8c5816289fe..32fdcd2d6e8f 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -298,6 +298,22 @@ void sk_clear_memalloc(struct sock *sk) } EXPORT_SYMBOL_GPL(sk_clear_memalloc); +int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) +{ + int ret; + unsigned long pflags = current->flags; + + /* these should have been dropped before queueing */ + BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); + + current->flags |= PF_MEMALLOC; + ret = sk->sk_backlog_rcv(sk, skb); + tsk_restore_flags(current, pflags, PF_MEMALLOC); + + return ret; +} +EXPORT_SYMBOL(__sk_backlog_rcv); + #if defined(CONFIG_CGROUPS) #if !defined(CONFIG_NET_CLS_CGROUP) int net_cls_subsys_id = -1; |