Home
last modified time | relevance | path

Searched hist:c722c625dbe2758d53365c0ed7d401b0e286f2cf (Results 1 – 1 of 1) sorted by relevance

/openbmc/linux/drivers/net/
H A Dtun.cdiff c722c625dbe2758d53365c0ed7d401b0e286f2cf Wed Jun 03 23:45:55 CDT 2009 Herbert Xu <herbert@gondor.apana.org.au> tun: Only wake up writers

When I added socket accounting to tun I inadvertently introduced
spurious wake-up events that kills qemu performance. The problem
occurs when qemu polls on the tun fd for read, and then transmits
packets. For each packet transmitted, we will wake up qemu even
if it only cares about read events.

Now this affects all sockets, but it is only a new problem for
tun. So this patch tries to fix it for tun first and we can then
look at the problem in general.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>