Commit e89df813 authored Jan 13, 2017 by Eric Dumazet Committed by David S. Miller Jan 16, 2017

netlink: do not enter direct reclaim from netlink_trim()



In commit d35c99ff ("netlink: do not enter direct reclaim from
netlink_dump()") we made sure to not trigger expensive memory reclaim.

Problem is that a bit later, netlink_trim() might be called and
trigger memory reclaim.

netlink_trim() should be best effort, and really as fast as possible.
Under memory pressure, it is fine to not trim this skb.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 3be0679b

net/netlink/af_netlink.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -1210,7 +1210,9 @@ static struct sk_buff netlink_trim(struct sk_buff skb, gfp_t allocation)
		skb = nskb;
		}

		if (!pskb_expand_head(skb, 0, -delta, allocation))
		if (!pskb_expand_head(skb, 0, -delta,
		(allocation & ~__GFP_DIRECT_RECLAIM) \|
		__GFP_NOWARN \| __GFP_NORETRY))
		skb->truesize -= delta;

		return skb;