[PATCH 3.19.y-ckt 62/70] tcp: convert cached rtt from usec to jiffies when feeding initial rto

From: Kamal Mostafa
Date: Wed Mar 16 2016 - 16:12:45 EST


v3.19.8-ckt17 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>

commit 9bdfb3b79e61c60e1a3e2dc05ad164528afa6b8a upstream.

Currently it's converted into msecs, thus HZ=1000 intact.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Fixes: 740b0f1841f6 ("tcp: switch rtt estimations to usec resolution")
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
net/ipv4/tcp_metrics.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index ed9c9a9..c90e76c 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -550,7 +550,7 @@ reset:
*/
if (crtt > tp->srtt_us) {
/* Set RTO like tcp_rtt_estimator(), but from cached RTT. */
- crtt /= 8 * USEC_PER_MSEC;
+ crtt /= 8 * USEC_PER_SEC / HZ;
inet_csk(sk)->icsk_rto = crtt + max(2 * crtt, tcp_rto_min(sk));
} else if (tp->srtt_us == 0) {
/* RFC6298: 5.7 We've failed to get a valid RTT sample from
--
2.7.0