From 7bbf55ea7a85748e02c9b3e966c1812032c48eb8 Mon Sep 17 00:00:00 2001
From: Sebastien Lorrain <sebastien.lorrain01@gmail.com>
Date: Wed, 15 Apr 2015 11:53:53 -0400
Subject: [PATCH] Add namespace info in sched_fork and statedump

Modifications to sched_fork : Add a field for parent and child pid
namespace inode (as in /proc/$PID/ns/pid). Also add a field for the
child VTID.

Modifications to lttng_statedump_process_state : Add a field for the pid
namespace inode of the task.

Signed-off-by: Sebastien Lorrain <sebastien.lorrain01@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 .../events/lttng-module/lttng-statedump.h     | 11 ++++
 instrumentation/events/lttng-module/sched.h   | 63 ++++++++++++++++++-
 2 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/instrumentation/events/lttng-module/lttng-statedump.h b/instrumentation/events/lttng-module/lttng-statedump.h
index 23690370..916a6c5c 100644
--- a/instrumentation/events/lttng-module/lttng-statedump.h
+++ b/instrumentation/events/lttng-module/lttng-statedump.h
@@ -8,6 +8,14 @@
 #include <linux/nsproxy.h>
 #include <linux/pid_namespace.h>
 #include <linux/types.h>
+#include <linux/version.h>
+
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,19,0))
+#define lttng_proc_inum ns.inum
+#else
+#define lttng_proc_inum proc_inum
+#endif
 
 LTTNG_TRACEPOINT_EVENT(lttng_statedump_start,
 	TP_PROTO(struct lttng_session *session),
@@ -60,6 +68,9 @@ LTTNG_TRACEPOINT_EVENT(lttng_statedump_process_state,
 		ctf_integer(int, submode, submode)
 		ctf_integer(int, status, status)
 		ctf_integer(int, ns_level, pid_ns ? pid_ns->level : 0)
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
+		ctf_integer(unsigned int, ns_inum, pid_ns ? pid_ns->lttng_proc_inum : 0)
+#endif
 	)
 )
 
diff --git a/instrumentation/events/lttng-module/sched.h b/instrumentation/events/lttng-module/sched.h
index ac61bcef..6e42fc62 100644
--- a/instrumentation/events/lttng-module/sched.h
+++ b/instrumentation/events/lttng-module/sched.h
@@ -6,12 +6,21 @@
 
 #include "../../../probes/lttng-tracepoint-event.h"
 #include <linux/sched.h>
+#include <linux/pid_namespace.h>
 #include <linux/binfmts.h>
 #include <linux/version.h>
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,9,0))
 #include <linux/sched/rt.h>
 #endif
 
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,19,0))
+#define lttng_proc_inum ns.inum
+#else
+#define lttng_proc_inum proc_inum
+#endif
+
+#define LTTNG_MAX_PID_NS_LEVEL 32
+
 #ifndef _TRACE_SCHED_DEF_
 #define _TRACE_SCHED_DEF_
 
@@ -288,19 +297,71 @@ LTTNG_TRACEPOINT_EVENT(sched_process_wait,
  * == child_pid, while creation of a thread yields to child_tid !=
  * child_pid.
  */
-LTTNG_TRACEPOINT_EVENT(sched_process_fork,
+LTTNG_TRACEPOINT_EVENT_CODE(sched_process_fork,
 
 	TP_PROTO(struct task_struct *parent, struct task_struct *child),
 
 	TP_ARGS(parent, child),
 
+	TP_locvar(
+		pid_t vtids[LTTNG_MAX_PID_NS_LEVEL];
+		unsigned int ns_level;
+	),
+
+	TP_code(
+		if (child) {
+			struct pid *child_pid;
+			unsigned int i;
+
+			child_pid = task_pid(child);
+			tp_locvar->ns_level =
+				min_t(unsigned int, child_pid->level + 1,
+					LTTNG_MAX_PID_NS_LEVEL);
+			for (i = 0; i < tp_locvar->ns_level; i++)
+				tp_locvar->vtids[i] = child_pid->numbers[i].nr;
+		}
+	),
+
 	TP_FIELDS(
 		ctf_array_text(char, parent_comm, parent->comm, TASK_COMM_LEN)
 		ctf_integer(pid_t, parent_tid, parent->pid)
 		ctf_integer(pid_t, parent_pid, parent->tgid)
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
+		ctf_integer(unsigned int, parent_ns_inum,
+			({
+				unsigned int parent_ns_inum = 0;
+
+				if (parent) {
+					struct pid_namespace *pid_ns;
+
+					pid_ns = task_active_pid_ns(parent);
+					if (pid_ns)
+						parent_ns_inum =
+							pid_ns->lttng_proc_inum;
+				}
+				parent_ns_inum;
+			}))
+#endif
 		ctf_array_text(char, child_comm, child->comm, TASK_COMM_LEN)
 		ctf_integer(pid_t, child_tid, child->pid)
+		ctf_sequence(pid_t, vtids, tp_locvar->vtids, u8, tp_locvar->ns_level)
 		ctf_integer(pid_t, child_pid, child->tgid)
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
+		ctf_integer(unsigned int, child_ns_inum,
+			({
+				unsigned int child_ns_inum = 0;
+
+				if (child) {
+					struct pid_namespace *pid_ns;
+
+					pid_ns = task_active_pid_ns(child);
+					if (pid_ns)
+						child_ns_inum =
+							pid_ns->lttng_proc_inum;
+				}
+				child_ns_inum;
+			}))
+#endif
 	)
 )
 
-- 
2.34.1