lttng-tools: Allow reconnect to relayd

If relayd is started after connection attempt from consumerd it will
leave the session in disconnected state and causes the following
inconvenience. This is covered by an upstream feature, see
https://bugs.lttng.org/issues/883. Before it's done, this patches
allows users to reconnect to relayd.

root@localhost:~# lttng enable-event --userspace --all
Error: Events: UST create channel failed (channel channel0, session trace_session)
root@localhost:~# lttng-relayd -b
Warning: No tracing group detected
root@localhost:~# lttng enable-event --userspace --all
Error: Events: UST create channel failed (channel channel0, session trace_session)

(From OE-Core rev: 6f0079a6c3cc8926423cff3a927a78dcecede90d)

Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-kernel/lttng/lttng-tools/0001-Allow-multiple-attempts-to-connect-to-relayd.patch

@@ -0,0 +1,43 @@
+From 70eff899104b86bae02862927c76caaef5de5d3c Mon Sep 17 00:00:00 2001
+From: Mikael Beckius <mikael.beckius@windriver.com>
+Date: Thu, 7 May 2015 16:14:25 +0200
+Subject: [PATCH] Allow multiple attempts to connect to relayd.
+
+It is unclear why a session needs to be made
+unusable after a failure to connect to relayd
+since a check for a relayd connection is
+always made before a session can be configured.
+
+The behaviour was introduced in:
+d9078d0c000d04d49c599a72c1a725026b636ec0
+
+Signed-off-by: Mikael Beckius <mikael.beckius@windriver.com>
+[ The context has moved, adjust the hunk accordingly ]
+Signed-off-by: He Zhe <zhe.he@windriver.com>
+Upstream-Status: Pending
+---
+ src/bin/lttng-sessiond/cmd.c |    8 --------
+ 1 file changed, 8 deletions(-)
+
+diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
+index 73b4ce3..36f62ee 100644
+--- a/src/bin/lttng-sessiond/cmd.c
++++ b/src/bin/lttng-sessiond/cmd.c
+@@ -689,14 +689,6 @@ close_sock:
+ 	free(rsock);
+ 
+ error:
+-	if (ret != LTTNG_OK) {
+-		/*
+-		 * The consumer output for this session should not be used anymore
+-		 * since the relayd connection failed thus making any tracing or/and
+-		 * streaming not usable.
+-		 */
+-		consumer->enabled = 0;
+-	}
+ 	return ret;
+ }
+ 
+-- 
+1.7.9.5
+

meta/recipes-kernel/lttng/lttng-tools_2.9.5.bb

@@ -30,6 +30,7 @@ PACKAGECONFIG_remove_riscv64 = "lttng-ust"
 SRC_URI = "https://lttng.org/files/lttng-tools/lttng-tools-${PV}.tar.bz2 \
            file://x32.patch \
            file://run-ptest \
+           file://0001-Allow-multiple-attempts-to-connect-to-relayd.patch \
            "
 
 SRC_URI[md5sum] = "051224eb991aee07f8721ff1877d0b96"