From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Thu, 21 Jul 2011 16:18:35 +0000 (-0400)
Subject: Fix vpid/vppid/vtid contexts handling of sched_switch vs exit NULL nsproxy
X-Git-Tag: v2.0-pre1~6
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=90f96adf9b02ecdb8c982bfda64fbfd4b11c34a8;p=lttng-modules.git

Fix vpid/vppid/vtid contexts handling of sched_switch vs exit NULL nsproxy

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/lttng-context-vpid.c b/lttng-context-vpid.c
index f12eb97e..3f16e03a 100644
--- a/lttng-context-vpid.c
+++ b/lttng-context-vpid.c
@@ -32,7 +32,13 @@ void vpid_record(struct lttng_ctx_field *field,
 {
 	pid_t vpid;
 
-	vpid = task_tgid_vnr(current);
+	/*
+	 * nsproxy can be NULL when scheduled out of exit.
+	 */
+	if (!current->nsproxy)
+		vpid = 0;
+	else
+		vpid = task_tgid_vnr(current);
 	lib_ring_buffer_align_ctx(ctx, ltt_alignof(vpid));
 	chan->ops->event_write(ctx, &vpid, sizeof(vpid));
 }
diff --git a/lttng-context-vppid.c b/lttng-context-vppid.c
index 4abf7846..f01b0206 100644
--- a/lttng-context-vppid.c
+++ b/lttng-context-vppid.c
@@ -31,10 +31,18 @@ void vppid_record(struct lttng_ctx_field *field,
 		  struct lib_ring_buffer_ctx *ctx,
 		  struct ltt_channel *chan)
 {
+	struct task_struct *parent;
 	pid_t vppid;
 
+	/*
+	 * nsproxy can be NULL when scheduled out of exit.
+	 */
 	rcu_read_lock();
-	vppid = task_tgid_vnr(current->real_parent);
+	parent = rcu_dereference(current->real_parent);
+	if (!parent->nsproxy)
+		vppid = 0;
+	else
+		vppid = task_tgid_vnr(parent);
 	rcu_read_unlock();
 	lib_ring_buffer_align_ctx(ctx, ltt_alignof(vppid));
 	chan->ops->event_write(ctx, &vppid, sizeof(vppid));
diff --git a/lttng-context-vtid.c b/lttng-context-vtid.c
index c428911e..264bbb30 100644
--- a/lttng-context-vtid.c
+++ b/lttng-context-vtid.c
@@ -32,7 +32,13 @@ void vtid_record(struct lttng_ctx_field *field,
 {
 	pid_t vtid;
 
-	vtid = task_pid_vnr(current);
+	/*
+	 * nsproxy can be NULL when scheduled out of exit.
+	 */
+	if (!current->nsproxy)
+		vtid = 0;
+	else
+		vtid = task_pid_vnr(current);
 	lib_ring_buffer_align_ctx(ctx, ltt_alignof(vtid));
 	chan->ops->event_write(ctx, &vtid, sizeof(vtid));
 }