From 29a22bc0a7fcc25e02b1fd173c8f0095d653d501 Mon Sep 17 00:00:00 2001
From: Olivier Houchard <ohouchard@haproxy.com>
Date: Tue, 4 Dec 2018 18:16:45 +0100
Subject: [PATCH] MEDIUM: h1: Realign the ibuf before calling rcv_buf if
 needed.

If the ibuf only contains a small amount of data, realign it
before calling rcv_buf(), as it's probably going to be cheaper
to do so than to do 2 calls to recv().
---
 src/mux_h1.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/mux_h1.c b/src/mux_h1.c
index b0d556700..1c980dca6 100644
--- a/src/mux_h1.c
+++ b/src/mux_h1.c
@@ -1484,6 +1484,13 @@ static int h1_recv(struct h1c *h1c)
 		goto end;
 	}
 
+	/*
+	 * If we only have a small amount of data, realign it,
+	 * it's probably cheaper than doing 2 recv() calls.
+	 */
+	if (b_data(&h1c->ibuf) > 0 && b_data(&h1c->ibuf) < 128)
+		b_slow_realign(&h1c->ibuf, trash.area, 0);
+
 	max = b_room(&h1c->ibuf);
 	if (max) {
 		h1c->flags &= ~H1C_F_IN_FULL;