From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx176.postini.com [74.125.245.176]) by kanga.kvack.org (Postfix) with SMTP id 76A3B6B00DD for ; Thu, 21 Jun 2012 12:30:49 -0400 (EDT) Date: Thu, 21 Jun 2012 18:30:29 +0200 From: Sebastian Andrzej Siewior Subject: Re: [PATCH 10/17] netvm: Allow skb allocation to use PFMEMALLOC reserves Message-ID: <20120621163029.GB6045@breakpoint.cc> References: <1340192652-31658-1-git-send-email-mgorman@suse.de> <1340192652-31658-11-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1340192652-31658-11-git-send-email-mgorman@suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , Linux-MM , Linux-Netdev , LKML , David Miller , Neil Brown , Peter Zijlstra , Mike Christie , Eric B Munson > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > index 1d6ecc8..9a58dcc 100644 > --- a/net/core/skbuff.c > +++ b/net/core/skbuff.c > @@ -167,14 +206,19 @@ static void skb_under_panic(struct sk_buff *skb, int sz, void *here) > * %GFP_ATOMIC. > */ > struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, > - int fclone, int node) > + int flags, int node) > { > struct kmem_cache *cache; > struct skb_shared_info *shinfo; > struct sk_buff *skb; > u8 *data; > + bool pfmemalloc; > > - cache = fclone ? skbuff_fclone_cache : skbuff_head_cache; > + cache = (flags & SKB_ALLOC_FCLONE) > + ? skbuff_fclone_cache : skbuff_head_cache; > + > + if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX)) > + gfp_mask |= __GFP_MEMALLOC; > > /* Get the HEAD */ > skb = kmem_cache_alloc_node(cache, gfp_mask & ~__GFP_DMA, node); This is mostly used by nic to refil their RX skb pool. You add the __GFP_MEMALLOC to the allocation to rise the change of a successfull refill for the swap case. A few drivers use build_skb() to create the skb. __netdev_alloc_skb() shouldn't be affected since the allocation happens with GFP_ATOMIC. Looking at TG3 it uses build_skb() and get_pages() / kmalloc(). Shouldn't this be some considered? Sebastian -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org