From 05ac42455fab8bba252bf124d6c450402429fd39 Mon Sep 17 00:00:00 2001
From: Thierry FOURNIER <tfournier@exceliance.fr>
Date: Fri, 27 Feb 2015 18:37:27 +0100
Subject: [PATCH] MEDIUM: lua: Lua initialisation "on demand"

Actually, the Lua context is always initilized in each
session, even if the session doesn't use Lua. This
behavior cause 5% performances loss.

This patch initilize the Lua only if it is use by the
session. The initialization is now on demand.
---
 src/hlua.c    | 36 ++++++++++++++++++++++++++++++++++++
 src/session.c | 13 ++++---------
 2 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/src/hlua.c b/src/hlua.c
index de27ba25ab..a0e4d91b49 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -2709,6 +2709,18 @@ static int hlua_sample_conv_wrapper(struct session *session, const struct arg *a
 {
 	struct hlua_function *fcn = (struct hlua_function *)private;
 
+	/* In the execution wrappers linked with a session, the
+	 * Lua context can be not initialized. This behavior
+	 * permits to save performances because a systematic
+	 * Lua initialization cause 5% performances loss.
+	 */
+	if (!session->hlua.T && !hlua_ctx_init(&session->hlua, session->task)) {
+		send_log(session->be, LOG_ERR, "Lua converter '%s': can't initialize Lua context.", fcn->name);
+		if (!(global.mode & MODE_QUIET) || (global.mode & MODE_VERBOSE))
+			Alert("Lua converter '%s': can't initialize Lua context.\n", fcn->name);
+		return 0;
+	}
+
 	/* If it is the first run, initialize the data for the call. */
 	if (session->hlua.state == HLUA_STOP) {
 		/* Check stack available size. */
@@ -2796,6 +2808,18 @@ static int hlua_sample_fetch_wrapper(struct proxy *px, struct session *s, void *
 {
 	struct hlua_function *fcn = (struct hlua_function *)private;
 
+	/* In the execution wrappers linked with a session, the
+	 * Lua context can be not initialized. This behavior
+	 * permits to save performances because a systematic
+	 * Lua initialization cause 5% performances loss.
+	 */
+	if (!s->hlua.T && !hlua_ctx_init(&s->hlua, s->task)) {
+		send_log(s->be, LOG_ERR, "Lua sample-fetch '%s': can't initialize Lua context.", fcn->name);
+		if (!(global.mode & MODE_QUIET) || (global.mode & MODE_VERBOSE))
+			Alert("Lua sample-fetch '%s': can't initialize Lua context.\n", fcn->name);
+		return 0;
+	}
+
 	/* If it is the first run, initialize the data for the call. */
 	if (s->hlua.state == HLUA_STOP) {
 		/* Check stack available size. */
@@ -3063,6 +3087,18 @@ static int hlua_request_act_wrapper(struct hlua_rule *rule, struct proxy *px,
 {
 	char **arg;
 
+	/* In the execution wrappers linked with a session, the
+	 * Lua context can be not initialized. This behavior
+	 * permits to save performances because a systematic
+	 * Lua initialization cause 5% performances loss.
+	 */
+	if (!s->hlua.T && !hlua_ctx_init(&s->hlua, s->task)) {
+		send_log(px, LOG_ERR, "Lua action '%s': can't initialize Lua context.", rule->fcn.name);
+		if (!(global.mode & MODE_QUIET) || (global.mode & MODE_VERBOSE))
+			Alert("Lua action '%s': can't initialize Lua context.\n", rule->fcn.name);
+		return 0;
+	}
+
 	/* If it is the first run, initialize the data for the call. */
 	if (s->hlua.state == HLUA_STOP) {
 		/* Check stack available size. */
diff --git a/src/session.c b/src/session.c
index 7ab91e6b6b..77ec4ca2ab 100644
--- a/src/session.c
+++ b/src/session.c
@@ -545,8 +545,7 @@ int session_complete(struct session *s)
 	txn->rsp.chn = s->rep;
 
 #ifdef USE_LUA
-	if (!hlua_ctx_init(&s->hlua, s->task))
-		goto out_free_rep;
+	s->hlua.T = NULL;
 #endif
 
 	/* finish initialization of the accepted file descriptor */
@@ -557,7 +556,7 @@ int session_complete(struct session *s)
 		 * finished (=0, eg: monitoring), in both situations,
 		 * we can release everything and close.
 		 */
-		goto out_free_lua;
+		goto out_free_rep;
 	}
 
 	/* if logs require transport layer information, note it on the connection */
@@ -575,11 +574,6 @@ int session_complete(struct session *s)
 	return 1;
 
 	/* Error unrolling */
- out_free_lua:
-#ifdef USE_LUA
-	hlua_ctx_destroy(&s->hlua);
-#endif
-
  out_free_rep:
 	pool_free2(pool2_channel, s->rep);
  out_free_req:
@@ -642,7 +636,8 @@ static void session_free(struct session *s)
 		session_offer_buffers();
 
 #ifdef USE_LUA
-	hlua_ctx_destroy(&s->hlua);
+	if (s->hlua.T)
+		hlua_ctx_destroy(&s->hlua);
 #endif
 
 	pool_free2(pool2_channel, s->req);
-- 
2.47.3