net: poll/select low latency socket support
select/poll busy-poll support.
Split sysctl value into two separate ones, one for read and one for poll.
updated Documentation/sysctl/net.txt
Add a new poll flag POLL_LL. When this flag is set, sock_poll will call
sk_poll_ll if possible. sock_poll sets this flag in its return value
to indicate to select/poll when a socket that can busy poll is found.
When poll/select have nothing to report, call the low-level
sock_poll again until we are out of time or we find something.
Once the system call finds something, it stops setting POLL_LL, so it can
return the result to the user ASAP.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/sock.c b/net/core/sock.c
index 1e744b1..b6c619f 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2307,7 +2307,7 @@
#ifdef CONFIG_NET_LL_RX_POLL
sk->sk_napi_id = 0;
- sk->sk_ll_usec = sysctl_net_ll_poll;
+ sk->sk_ll_usec = sysctl_net_ll_read;
#endif
/*