[TCP]: Limit processing lost_retrans loop to work-to-do cases

This addition of lost_retrans_low to tcp_sock might be
unnecessary, it's not clear how often lost_retrans worker is
executed when there wasn't work to do.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 9ff456e8d6c7..c5b94c1a5ee2 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -348,6 +348,8 @@ struct tcp_sock {
         int     lost_cnt_hint;
         int     retransmit_cnt_hint;
 
+        u32     lost_retrans_low;       /* Sent seq after any rxmit (lowest) */
+
         u16     advmss;         /* Advertised MSS                       */
         u16     prior_ssthresh; /* ssthresh saved at recovery start     */
         u32     lost_out;       /* Lost packets                 */