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-Tag: v2.7.0-rc2~42
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=bfca0e92334dfb99fe792a91e9fbc471615f1aee;p=lttng-tools.git

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 9519eb397..6454449bd 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -2962,6 +2962,8 @@ 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) {
@@ -4021,6 +4023,7 @@ setup_error:
 		session_unlock_list();
 	}
 init_setup_error:
+	assert(!rcu_read_ongoing());
 	return ret;
 }