From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Mon, 7 Sep 2015 14:36:08 +0000 (-0400)
Subject: Add rcu_read_ongoing() assertions around process_client_msg
X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=commitdiff_plain;h=3745d31545c667ea0e5151fc2a2b0b90f59c1a2d

Add rcu_read_ongoing() assertions around process_client_msg

process_client_msg ensures that RCU read-side lock should not be held
when calling it. Validate this using rcu_read_ongoing() at the entry and
exit points of this function. This allows us to catch unbalanced RCU
read-side lock within commands quickly.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 7c48e4da4..0e7de6e5e 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -2972,6 +2972,8 @@ static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
 
 	DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
 
+	assert(!rcu_read_ongoing());
+
 	*sock_error = 0;
 
 	switch (cmd_ctx->lsm->cmd_type) {
@@ -4059,6 +4061,7 @@ setup_error:
 		session_unlock_list();
 	}
 init_setup_error:
+	assert(!rcu_read_ongoing());
 	return ret;
 }