+/*
+ * Called with task lock held.
+ */
+static
+void lttng_statedump_process_ns(struct lttng_session *session,
+ struct task_struct *p,
+ enum lttng_thread_type type,
+ enum lttng_execution_mode mode,
+ enum lttng_execution_submode submode,
+ enum lttng_process_status status)
+{
+ struct nsproxy *proxy;
+ struct pid_namespace *pid_ns;
+
+ /*
+ * Back and forth on locking strategy within Linux upstream for nsproxy.
+ * See Linux upstream commit 728dba3a39c66b3d8ac889ddbe38b5b1c264aec3
+ * "namespaces: Use task_lock and not rcu to protect nsproxy"
+ * for details.
+ */
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) || \
+ LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,36, 3,14,0,0) || \
+ LTTNG_UBUNTU_KERNEL_RANGE(3,16,1,11, 3,17,0,0) || \
+ LTTNG_RHEL_KERNEL_RANGE(3,10,0,229,13,0, 3,11,0,0,0,0))
+ proxy = p->nsproxy;
+#else
+ rcu_read_lock();
+ proxy = task_nsproxy(p);
+#endif
+ if (proxy) {
+ pid_ns = lttng_get_proxy_pid_ns(proxy);
+ do {
+ trace_lttng_statedump_process_state(session,
+ p, type, mode, submode, status, pid_ns);
+ pid_ns = pid_ns->parent;
+ } while (pid_ns);
+ } else {
+ trace_lttng_statedump_process_state(session,
+ p, type, mode, submode, status, NULL);
+ }
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) || \
+ LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,36, 3,14,0,0) || \
+ LTTNG_UBUNTU_KERNEL_RANGE(3,16,1,11, 3,17,0,0) || \
+ LTTNG_RHEL_KERNEL_RANGE(3,10,0,229,13,0, 3,11,0,0,0,0))
+ /* (nothing) */
+#else
+ rcu_read_unlock();
+#endif
+}
+