Re: sk_lock: inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W}usage

[David Miller]

From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Date: Fri, 10 Jul 2009 16:02:47 +0800

> On Fri, Jul 10, 2009 at 04:00:17PM +0800, Wu Fengguang wrote:
>> 
>> The (sk_allocation & ~__GFP_WAIT) cases should be rare, but I guess
>> the networking code shall do it anyway, because sk_allocation defaults
>> to GFP_KERNEL. It seems that currently the networking code simply uses
>> a lot of GFP_ATOMIC, do they really mean "I cannot sleep"?
> 
> Yep because they're done from softirq context.

Yes, this is the core issue.

All of Wu's talk about how "GFP_ATOMIC will wake up kswapd and
therefore can succeed just as well as GFP_KERNEL" is not relevant,
because GFP_ATOMIC means sleeping is not allowed.
--
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/