Re: __alloc_pages() failures reported due to fragmentation

From: Larry Woodman
Date: Fri Nov 03 2006 - 07:48:32 EST


Arjan van de Ven wrote:

--- linux-2.6.18.noarch/net/core/sock.c.orig
+++ linux-2.6.18.noarch/net/core/sock.c
@@ -1154,7 +1154,7 @@ static struct sk_buff *sock_alloc_send_p
goto failure;

if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
- skb = alloc_skb(header_len, sk->sk_allocation);
+ skb = alloc_skb(header_len, gfp_mask);
if (skb) {
int npages;
int i;



Hi,

this is not actually right though... sk_allocation is very possible to
have a restricting mask compared to the one passed in (say "no highmem"
or even GFP_DMA) and you now discard this... probably better would be to
calculate a set of "transient" flags that you then or into the
sk_allocation mask at this time...

Greetings,
Arjan van de Ven



Hi Arjan. Right but this just includes __GFP_REPEAT in the mask so we can
defrag in __alloc_pages and only if GFP_WAIT was passed in origionally.

Larry


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/