[lttng-modules.git] / lttng-statedump-impl.c

/*
 * lttng-statedump.c
 *
 * Linux Trace Toolkit Next Generation Kernel State Dump
 *
 * Copyright 2005 Jean-Hugues Deschenes <jean-hugues.deschenes@polymtl.ca>
 * Copyright 2006-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; only
 * version 2.1 of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * Changes:
 *	Eric Clement:                   Add listing of network IP interface
 *	2006, 2007 Mathieu Desnoyers	Fix kernel threads
 *	                                Various updates
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/inet.h>
#include <linux/ip.h>
#include <linux/kthread.h>
#include <linux/proc_fs.h>
#include <linux/file.h>
#include <linux/interrupt.h>
#include <linux/irqnr.h>
#include <linux/cpu.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fdtable.h>
#include <linux/swap.h>
#include <linux/wait.h>
#include <linux/mutex.h>

#include "lttng-events.h"
#include "wrapper/irqdesc.h"
#include "wrapper/spinlock.h"

#ifdef CONFIG_GENERIC_HARDIRQS
#include <linux/irq.h>
#endif

/* Define the tracepoints, but do not build the probes */
#define CREATE_TRACE_POINTS
#define TRACE_INCLUDE_PATH ../instrumentation/events/lttng-module
#define TRACE_INCLUDE_FILE lttng-statedump
#include "instrumentation/events/lttng-module/lttng-statedump.h"

/*
 * Protected by the trace lock.
 */
static struct delayed_work cpu_work[NR_CPUS];
static DECLARE_WAIT_QUEUE_HEAD(statedump_wq);
static atomic_t kernel_threads_to_run;

enum lttng_thread_type {
	LTTNG_USER_THREAD = 0,
	LTTNG_KERNEL_THREAD = 1,
};

enum lttng_execution_mode {
	LTTNG_USER_MODE = 0,
	LTTNG_SYSCALL = 1,
	LTTNG_TRAP = 2,
	LTTNG_IRQ = 3,
	LTTNG_SOFTIRQ = 4,
	LTTNG_MODE_UNKNOWN = 5,
};

enum lttng_execution_submode {
	LTTNG_NONE = 0,
	LTTNG_UNKNOWN = 1,
};

enum lttng_process_status {
	LTTNG_UNNAMED = 0,
	LTTNG_WAIT_FORK = 1,
	LTTNG_WAIT_CPU = 2,
	LTTNG_EXIT = 3,
	LTTNG_ZOMBIE = 4,
	LTTNG_WAIT = 5,
	LTTNG_RUN = 6,
	LTTNG_DEAD = 7,
};

#ifdef CONFIG_INET
static
void lttng_enumerate_device(struct lttng_session *session,
		struct net_device *dev)
{
	struct in_device *in_dev;
	struct in_ifaddr *ifa;

	if (dev->flags & IFF_UP) {
		in_dev = in_dev_get(dev);
		if (in_dev) {
			for (ifa = in_dev->ifa_list; ifa != NULL;
			     ifa = ifa->ifa_next) {
				trace_lttng_statedump_network_interface(
					session, dev, ifa);
			}
			in_dev_put(in_dev);
		}
	} else {
		trace_lttng_statedump_network_interface(
			session, dev, NULL);
	}
}

static
int lttng_enumerate_network_ip_interface(struct lttng_session *session)
{
	struct net_device *dev;

	read_lock(&dev_base_lock);
	for_each_netdev(&init_net, dev)
		lttng_enumerate_device(session, dev);
	read_unlock(&dev_base_lock);

	return 0;
}
#else /* CONFIG_INET */
static inline
int lttng_enumerate_network_ip_interface(struct lttng_session *session)
{
	return 0;
}
#endif /* CONFIG_INET */


static
void lttng_enumerate_task_fd(struct lttng_session *session,
		struct task_struct *p, char *tmp)
{
	struct fdtable *fdt;
	struct file *filp;
	unsigned int i;
	const unsigned char *path;

	task_lock(p);
	if (!p->files)
		goto unlock_task;
	spin_lock(&p->files->file_lock);
	fdt = files_fdtable(p->files);
	for (i = 0; i < fdt->max_fds; i++) {
		filp = fcheck_files(p->files, i);
		if (!filp)
			continue;
		path = d_path(&filp->f_path, tmp, PAGE_SIZE);
		/* Make sure we give at least some info */
		trace_lttng_statedump_file_descriptor(session, p, i,
			IS_ERR(path) ?
				filp->f_dentry->d_name.name :
				path);
	}
	spin_unlock(&p->files->file_lock);
unlock_task:
	task_unlock(p);
}

static
int lttng_enumerate_file_descriptors(struct lttng_session *session)
{
	struct task_struct *p;
	char *tmp = (char *) __get_free_page(GFP_KERNEL);

	/* Enumerate active file descriptors */
	rcu_read_lock();
	for_each_process(p)
		lttng_enumerate_task_fd(session, p, tmp);
	rcu_read_unlock();
	free_page((unsigned long) tmp);
	return 0;
}

#if 0
/*
 * FIXME: we cannot take a mmap_sem while in a RCU read-side critical section
 * (scheduling in atomic). Normally, the tasklist lock protects this kind of
 * iteration, but it is not exported to modules.
 */
static
void lttng_enumerate_task_vm_maps(struct lttng_session *session,
		struct task_struct *p)
{
	struct mm_struct *mm;
	struct vm_area_struct *map;
	unsigned long ino;

	/* get_task_mm does a task_lock... */
	mm = get_task_mm(p);
	if (!mm)
		return;

	map = mm->mmap;
	if (map) {
		down_read(&mm->mmap_sem);
		while (map) {
			if (map->vm_file)
				ino = map->vm_file->f_dentry->d_inode->i_ino;
			else
				ino = 0;
			trace_lttng_statedump_vm_map(session, p, map, ino);
			map = map->vm_next;
		}
		up_read(&mm->mmap_sem);
	}
	mmput(mm);
}

static
int lttng_enumerate_vm_maps(struct lttng_session *session)
{
	struct task_struct *p;

	rcu_read_lock();
	for_each_process(p)
		lttng_enumerate_task_vm_maps(session, p);
	rcu_read_unlock();
	return 0;
}
#endif

#ifdef CONFIG_GENERIC_HARDIRQS

#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,39))
#define irq_desc_get_chip(desc) get_irq_desc_chip(desc)
#endif

static
void lttng_list_interrupts(struct lttng_session *session)
{
	unsigned int irq;
	unsigned long flags = 0;
	struct irq_desc *desc;

#define irq_to_desc	wrapper_irq_to_desc
	/* needs irq_desc */
	for_each_irq_desc(irq, desc) {
		struct irqaction *action;
		const char *irq_chip_name =
			irq_desc_get_chip(desc)->name ? : "unnamed_irq_chip";

		local_irq_save(flags);
		wrapper_desc_spin_lock(&desc->lock);
		for (action = desc->action; action; action = action->next) {
			trace_lttng_statedump_interrupt(session,
				irq, irq_chip_name, action);
		}
		wrapper_desc_spin_unlock(&desc->lock);
		local_irq_restore(flags);
	}
#undef irq_to_desc
}
#else
static inline
void list_interrupts(struct lttng_session *session)
{
}
#endif

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;

	rcu_read_lock();
	proxy = task_nsproxy(p);
	if (proxy) {
		pid_ns = proxy->pid_ns;
		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);
	}
	rcu_read_unlock();
}

static
int lttng_enumerate_process_states(struct lttng_session *session)
{
	struct task_struct *g, *p;

	rcu_read_lock();
	for_each_process(g) {
		p = g;
		do {
			enum lttng_execution_mode mode =
				LTTNG_MODE_UNKNOWN;
			enum lttng_execution_submode submode =
				LTTNG_UNKNOWN;
			enum lttng_process_status status;
			enum lttng_thread_type type;

			task_lock(p);
			if (p->exit_state == EXIT_ZOMBIE)
				status = LTTNG_ZOMBIE;
			else if (p->exit_state == EXIT_DEAD)
				status = LTTNG_DEAD;
			else if (p->state == TASK_RUNNING) {
				/* Is this a forked child that has not run yet? */
				if (list_empty(&p->rt.run_list))
					status = LTTNG_WAIT_FORK;
				else
					/*
					 * All tasks are considered as wait_cpu;
					 * the viewer will sort out if the task
					 * was really running at this time.
					 */
					status = LTTNG_WAIT_CPU;
			} else if (p->state &
				(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)) {
				/* Task is waiting for something to complete */
				status = LTTNG_WAIT;
			} else
				status = LTTNG_UNNAMED;
			submode = LTTNG_NONE;

			/*
			 * Verification of t->mm is to filter out kernel
			 * threads; Viewer will further filter out if a
			 * user-space thread was in syscall mode or not.
			 */
			if (p->mm)
				type = LTTNG_USER_THREAD;
			else
				type = LTTNG_KERNEL_THREAD;
			lttng_statedump_process_ns(session,
				p, type, mode, submode, status);
			task_unlock(p);
		} while_each_thread(g, p);
	}
	rcu_read_unlock();

	return 0;
}

static
void lttng_statedump_work_func(struct work_struct *work)
{
	if (atomic_dec_and_test(&kernel_threads_to_run))
		/* If we are the last thread, wake up do_lttng_statedump */
		wake_up(&statedump_wq);
}

static
int do_lttng_statedump(struct lttng_session *session)
{
	int cpu;

	printk(KERN_DEBUG "LTT state dump thread start\n");
	trace_lttng_statedump_start(session);
	lttng_enumerate_process_states(session);
	lttng_enumerate_file_descriptors(session);
	/* FIXME lttng_enumerate_vm_maps(session); */
	lttng_list_interrupts(session);
	lttng_enumerate_network_ip_interface(session);

	/* TODO lttng_dump_idt_table(session); */
	/* TODO lttng_dump_softirq_vec(session); */
	/* TODO lttng_list_modules(session); */
	/* TODO lttng_dump_swap_files(session); */

	/*
	 * Fire off a work queue on each CPU. Their sole purpose in life
	 * is to guarantee that each CPU has been in a state where is was in
	 * syscall mode (i.e. not in a trap, an IRQ or a soft IRQ).
	 */
	get_online_cpus();
	atomic_set(&kernel_threads_to_run, num_online_cpus());
	for_each_online_cpu(cpu) {
		INIT_DELAYED_WORK(&cpu_work[cpu], lttng_statedump_work_func);
		schedule_delayed_work_on(cpu, &cpu_work[cpu], 0);
	}
	/* Wait for all threads to run */
	wait_event(statedump_wq, (atomic_read(&kernel_threads_to_run) != 0));
	put_online_cpus();
	/* Our work is done */
	printk(KERN_DEBUG "LTT state dump end\n");
	trace_lttng_statedump_end(session);
	return 0;
}

/*
 * Called with session mutex held.
 */
int lttng_statedump_start(struct lttng_session *session)
{
	printk(KERN_DEBUG "LTTng: state dump begin\n");
	return do_lttng_statedump(session);
}
EXPORT_SYMBOL_GPL(lttng_statedump_start);

MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Jean-Hugues Deschenes");
MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Statedump");
Commit	Line	Data
c337ddc2	1	/*
886d51a3 MD	2	* lttng-statedump.c
886d51a3 MD	3	*
c337ddc2 MD	4	* Linux Trace Toolkit Next Generation Kernel State Dump
	5	*
	6	* Copyright 2005 Jean-Hugues Deschenes <jean-hugues.deschenes@polymtl.ca>
	7	* Copyright 2006-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
886d51a3 MD	9	* This library is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU Lesser General Public
	11	* License as published by the Free Software Foundation; only
	12	* version 2.1 of the License.
	13	*
	14	* This library is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* Lesser General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU Lesser General Public
	20	* License along with this library; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	22	*
c337ddc2 MD	23	* Changes:
	24	* Eric Clement: Add listing of network IP interface
	25	* 2006, 2007 Mathieu Desnoyers Fix kernel threads
	26	* Various updates
c337ddc2 MD	27	*/
	28
	29	#include <linux/init.h>
	30	#include <linux/module.h>
	31	#include <linux/netlink.h>
	32	#include <linux/inet.h>
	33	#include <linux/ip.h>
	34	#include <linux/kthread.h>
	35	#include <linux/proc_fs.h>
	36	#include <linux/file.h>
	37	#include <linux/interrupt.h>
	38	#include <linux/irqnr.h>
	39	#include <linux/cpu.h>
	40	#include <linux/netdevice.h>
	41	#include <linux/inetdevice.h>
	42	#include <linux/sched.h>
	43	#include <linux/mm.h>
	44	#include <linux/fdtable.h>
	45	#include <linux/swap.h>
	46	#include <linux/wait.h>
	47	#include <linux/mutex.h>
	48
	49	#include "lttng-events.h"
	50	#include "wrapper/irqdesc.h"
3a523f5b	51	#include "wrapper/spinlock.h"
c337ddc2 MD	52
	53	#ifdef CONFIG_GENERIC_HARDIRQS
	54	#include <linux/irq.h>
	55	#endif
	56
	57	/* Define the tracepoints, but do not build the probes */
	58	#define CREATE_TRACE_POINTS
	59	#define TRACE_INCLUDE_PATH ../instrumentation/events/lttng-module
	60	#define TRACE_INCLUDE_FILE lttng-statedump
	61	#include "instrumentation/events/lttng-module/lttng-statedump.h"
	62
	63	/*
	64	* Protected by the trace lock.
	65	*/
	66	static struct delayed_work cpu_work[NR_CPUS];
	67	static DECLARE_WAIT_QUEUE_HEAD(statedump_wq);
	68	static atomic_t kernel_threads_to_run;
	69
	70	enum lttng_thread_type {
	71	LTTNG_USER_THREAD = 0,
	72	LTTNG_KERNEL_THREAD = 1,
	73	};
	74
	75	enum lttng_execution_mode {
	76	LTTNG_USER_MODE = 0,
	77	LTTNG_SYSCALL = 1,
	78	LTTNG_TRAP = 2,
	79	LTTNG_IRQ = 3,
	80	LTTNG_SOFTIRQ = 4,
	81	LTTNG_MODE_UNKNOWN = 5,
	82	};
	83
	84	enum lttng_execution_submode {
	85	LTTNG_NONE = 0,
	86	LTTNG_UNKNOWN = 1,
	87	};
	88
	89	enum lttng_process_status {
	90	LTTNG_UNNAMED = 0,
	91	LTTNG_WAIT_FORK = 1,
	92	LTTNG_WAIT_CPU = 2,
	93	LTTNG_EXIT = 3,
	94	LTTNG_ZOMBIE = 4,
	95	LTTNG_WAIT = 5,
	96	LTTNG_RUN = 6,
	97	LTTNG_DEAD = 7,
	98	};
	99
	100	#ifdef CONFIG_INET
	101	static
	102	void lttng_enumerate_device(struct lttng_session *session,
	103	struct net_device *dev)
	104	{
	105	struct in_device *in_dev;
	106	struct in_ifaddr *ifa;
	107
	108	if (dev->flags & IFF_UP) {
	109	in_dev = in_dev_get(dev);
	110	if (in_dev) {
	111	for (ifa = in_dev->ifa_list; ifa != NULL;
	112	ifa = ifa->ifa_next) {
	113	trace_lttng_statedump_network_interface(
	114	session, dev, ifa);
	115	}
116	in_dev_put(in_dev);
117	}
118	} else {
119	trace_lttng_statedump_network_interface(
120	session, dev, NULL);
121	}
122	}
123
124	static
125	int lttng_enumerate_network_ip_interface(struct lttng_session *session)
126	{
127	struct net_device *dev;
128
129	read_lock(&dev_base_lock);
130	for_each_netdev(&init_net, dev)
131	lttng_enumerate_device(session, dev);
132	read_unlock(&dev_base_lock);
133
134	return 0;
135	}
136	#else /* CONFIG_INET */
137	static inline
138	int lttng_enumerate_network_ip_interface(struct lttng_session *session)
139	{
140	return 0;
141	}
142	#endif /* CONFIG_INET */
143
144
145	static
146	void lttng_enumerate_task_fd(struct lttng_session *session,
147	struct task_struct p, char tmp)
148	{
149	struct fdtable *fdt;
150	struct file *filp;
151	unsigned int i;
152	const unsigned char *path;
153
154	task_lock(p);
155	if (!p->files)
156	goto unlock_task;
157	spin_lock(&p->files->file_lock);
158	fdt = files_fdtable(p->files);
159	for (i = 0; i < fdt->max_fds; i++) {
160	filp = fcheck_files(p->files, i);
161	if (!filp)
162	continue;
163	path = d_path(&filp->f_path, tmp, PAGE_SIZE);
164	/* Make sure we give at least some info */
165	trace_lttng_statedump_file_descriptor(session, p, i,
166	IS_ERR(path) ?
167	filp->f_dentry->d_name.name :
168	path);
169	}
170	spin_unlock(&p->files->file_lock);
171	unlock_task:
172	task_unlock(p);
173	}
174
175	static
176	int lttng_enumerate_file_descriptors(struct lttng_session *session)
177	{
178	struct task_struct *p;
179	char tmp = (char ) __get_free_page(GFP_KERNEL);
180
181	/* Enumerate active file descriptors */
182	rcu_read_lock();
183	for_each_process(p)
184	lttng_enumerate_task_fd(session, p, tmp);
185	rcu_read_unlock();
186	free_page((unsigned long) tmp);
187	return 0;
188	}
189
0658bdda MD	190	#if 0
	191	/*
	192	* FIXME: we cannot take a mmap_sem while in a RCU read-side critical section
	193	* (scheduling in atomic). Normally, the tasklist lock protects this kind of
	194	* iteration, but it is not exported to modules.
	195	*/
c337ddc2 MD	196	static
	197	void lttng_enumerate_task_vm_maps(struct lttng_session *session,
	198	struct task_struct *p)
	199	{
	200	struct mm_struct *mm;
	201	struct vm_area_struct *map;
	202	unsigned long ino;
	203
	204	/* get_task_mm does a task_lock... */
	205	mm = get_task_mm(p);
	206	if (!mm)
	207	return;
	208
	209	map = mm->mmap;
	210	if (map) {
	211	down_read(&mm->mmap_sem);
	212	while (map) {
	213	if (map->vm_file)
	214	ino = map->vm_file->f_dentry->d_inode->i_ino;
	215	else
	216	ino = 0;
	217	trace_lttng_statedump_vm_map(session, p, map, ino);
	218	map = map->vm_next;
	219	}
	220	up_read(&mm->mmap_sem);
	221	}
	222	mmput(mm);
	223	}
	224
	225	static
	226	int lttng_enumerate_vm_maps(struct lttng_session *session)
	227	{
	228	struct task_struct *p;
	229
	230	rcu_read_lock();
	231	for_each_process(p)
	232	lttng_enumerate_task_vm_maps(session, p);
	233	rcu_read_unlock();
	234	return 0;
	235	}
0658bdda	236	#endif
c337ddc2 MD	237
c337ddc2 MD	238	#ifdef CONFIG_GENERIC_HARDIRQS
47faec4b JN	239
	240	#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,39))
	241	#define irq_desc_get_chip(desc) get_irq_desc_chip(desc)
	242	#endif
	243
c337ddc2 MD	244	static
	245	void lttng_list_interrupts(struct lttng_session *session)
	246	{
	247	unsigned int irq;
	248	unsigned long flags = 0;
	249	struct irq_desc *desc;
	250
	251	#define irq_to_desc wrapper_irq_to_desc
	252	/* needs irq_desc */
	253	for_each_irq_desc(irq, desc) {
	254	struct irqaction *action;
	255	const char *irq_chip_name =
	256	irq_desc_get_chip(desc)->name ? : "unnamed_irq_chip";
	257
	258	local_irq_save(flags);
3a523f5b	259	wrapper_desc_spin_lock(&desc->lock);
c337ddc2 MD	260	for (action = desc->action; action; action = action->next) {
	261	trace_lttng_statedump_interrupt(session,
	262	irq, irq_chip_name, action);
	263	}
3a523f5b	264	wrapper_desc_spin_unlock(&desc->lock);
c337ddc2 MD	265	local_irq_restore(flags);
	266	}
	267	#undef irq_to_desc
	268	}
	269	#else
	270	static inline
	271	void list_interrupts(struct lttng_session *session)
	272	{
	273	}
	274	#endif
	275
73e8ba37 JD	276	static
	277	void lttng_statedump_process_ns(struct lttng_session *session,
	278	struct task_struct *p,
	279	enum lttng_thread_type type,
	280	enum lttng_execution_mode mode,
	281	enum lttng_execution_submode submode,
	282	enum lttng_process_status status)
	283	{
	284	struct nsproxy *proxy;
	285	struct pid_namespace *pid_ns;
	286
	287	rcu_read_lock();
	288	proxy = task_nsproxy(p);
	289	if (proxy) {
	290	pid_ns = proxy->pid_ns;
	291	do {
	292	trace_lttng_statedump_process_state(session,
	293	p, type, mode, submode, status, pid_ns);
af73f727	294	pid_ns = pid_ns->parent;
73e8ba37 JD	295	} while (pid_ns);
	296	} else {
	297	trace_lttng_statedump_process_state(session,
	298	p, type, mode, submode, status, NULL);
	299	}
	300	rcu_read_unlock();
	301	}
	302
c337ddc2 MD	303	static
	304	int lttng_enumerate_process_states(struct lttng_session *session)
	305	{
	306	struct task_struct g, p;
	307
	308	rcu_read_lock();
	309	for_each_process(g) {
	310	p = g;
	311	do {
	312	enum lttng_execution_mode mode =
	313	LTTNG_MODE_UNKNOWN;
	314	enum lttng_execution_submode submode =
	315	LTTNG_UNKNOWN;
	316	enum lttng_process_status status;
	317	enum lttng_thread_type type;
	318
	319	task_lock(p);
	320	if (p->exit_state == EXIT_ZOMBIE)
	321	status = LTTNG_ZOMBIE;
	322	else if (p->exit_state == EXIT_DEAD)
	323	status = LTTNG_DEAD;
	324	else if (p->state == TASK_RUNNING) {
	325	/* Is this a forked child that has not run yet? */
	326	if (list_empty(&p->rt.run_list))
	327	status = LTTNG_WAIT_FORK;
	328	else
	329	/*
	330	* All tasks are considered as wait_cpu;
	331	* the viewer will sort out if the task
	332	* was really running at this time.
	333	*/
	334	status = LTTNG_WAIT_CPU;
	335	} else if (p->state &
	336	(TASK_INTERRUPTIBLE \| TASK_UNINTERRUPTIBLE)) {
	337	/* Task is waiting for something to complete */
	338	status = LTTNG_WAIT;
	339	} else
	340	status = LTTNG_UNNAMED;
	341	submode = LTTNG_NONE;
	342
	343	/*
	344	* Verification of t->mm is to filter out kernel
	345	* threads; Viewer will further filter out if a
	346	* user-space thread was in syscall mode or not.
	347	*/
	348	if (p->mm)
	349	type = LTTNG_USER_THREAD;
	350	else
	351	type = LTTNG_KERNEL_THREAD;
73e8ba37	352	lttng_statedump_process_ns(session,
c337ddc2 MD	353	p, type, mode, submode, status);
	354	task_unlock(p);
	355	} while_each_thread(g, p);
	356	}
	357	rcu_read_unlock();
	358
	359	return 0;
	360	}
	361
	362	static
	363	void lttng_statedump_work_func(struct work_struct *work)
	364	{
	365	if (atomic_dec_and_test(&kernel_threads_to_run))
	366	/* If we are the last thread, wake up do_lttng_statedump */
	367	wake_up(&statedump_wq);
	368	}
	369
	370	static
	371	int do_lttng_statedump(struct lttng_session *session)
	372	{
	373	int cpu;
	374
	375	printk(KERN_DEBUG "LTT state dump thread start\n");
	376	trace_lttng_statedump_start(session);
	377	lttng_enumerate_process_states(session);
	378	lttng_enumerate_file_descriptors(session);
0658bdda	379	/* FIXME lttng_enumerate_vm_maps(session); */
c337ddc2 MD	380	lttng_list_interrupts(session);
	381	lttng_enumerate_network_ip_interface(session);
	382
	383	/* TODO lttng_dump_idt_table(session); */
	384	/* TODO lttng_dump_softirq_vec(session); */
	385	/* TODO lttng_list_modules(session); */
	386	/* TODO lttng_dump_swap_files(session); */
	387
	388	/*
	389	* Fire off a work queue on each CPU. Their sole purpose in life
	390	* is to guarantee that each CPU has been in a state where is was in
	391	* syscall mode (i.e. not in a trap, an IRQ or a soft IRQ).
	392	*/
	393	get_online_cpus();
	394	atomic_set(&kernel_threads_to_run, num_online_cpus());
	395	for_each_online_cpu(cpu) {
	396	INIT_DELAYED_WORK(&cpu_work[cpu], lttng_statedump_work_func);
	397	schedule_delayed_work_on(cpu, &cpu_work[cpu], 0);
	398	}
	399	/* Wait for all threads to run */
8240b2e2	400	wait_event(statedump_wq, (atomic_read(&kernel_threads_to_run) != 0));
c337ddc2 MD	401	put_online_cpus();
	402	/* Our work is done */
	403	printk(KERN_DEBUG "LTT state dump end\n");
	404	trace_lttng_statedump_end(session);
	405	return 0;
	406	}
	407
	408	/*
	409	* Called with session mutex held.
	410	*/
	411	int lttng_statedump_start(struct lttng_session *session)
	412	{
	413	printk(KERN_DEBUG "LTTng: state dump begin\n");
	414	return do_lttng_statedump(session);
	415	}
	416	EXPORT_SYMBOL_GPL(lttng_statedump_start);
	417
	418	MODULE_LICENSE("GPL and additional rights");
	419	MODULE_AUTHOR("Jean-Hugues Deschenes");
	420	MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Statedump");