[deliverable/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"
#include "wrapper/fdtable.h"
#include "wrapper/nsproxy.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"

struct lttng_fd_ctx {
	char *page;
	struct lttng_session *session;
	struct task_struct *p;
};

/*
 * 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
int lttng_dump_one_fd(const void *p, struct file *file, unsigned int fd)
{
	const struct lttng_fd_ctx *ctx = p;
	const char *s = d_path(&file->f_path, ctx->page, PAGE_SIZE);

	if (IS_ERR(s)) {
		struct dentry *dentry = file->f_path.dentry;

		/* Make sure we give at least some info */
		spin_lock(&dentry->d_lock);
		trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd,
			dentry->d_name.name);
		spin_unlock(&dentry->d_lock);
		goto end;
	}
	trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd, s);
end:
	return 0;
}

static
void lttng_enumerate_task_fd(struct lttng_session *session,
		struct task_struct *p, char *tmp)
{
	struct lttng_fd_ctx ctx = { .page = tmp, .session = session, .p = p };

	task_lock(p);
	lttng_iterate_fd(p->files, 0, lttng_dump_one_fd, &ctx);
	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 = 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);
	}
	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;

	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 */
	trace_lttng_statedump_end(session);
	return 0;
}

/*
 * Called with session mutex held.
 */
int lttng_statedump_start(struct lttng_session *session)
{
	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"
361c023a	52	#include "wrapper/fdtable.h"
3247f8bd	53	#include "wrapper/nsproxy.h"
c337ddc2 MD	54
	55	#ifdef CONFIG_GENERIC_HARDIRQS
	56	#include <linux/irq.h>
	57	#endif
	58
	59	/* Define the tracepoints, but do not build the probes */
	60	#define CREATE_TRACE_POINTS
	61	#define TRACE_INCLUDE_PATH ../instrumentation/events/lttng-module
	62	#define TRACE_INCLUDE_FILE lttng-statedump
	63	#include "instrumentation/events/lttng-module/lttng-statedump.h"
	64
361c023a MD	65	struct lttng_fd_ctx {
	66	char *page;
	67	struct lttng_session *session;
	68	struct task_struct *p;
	69	};
	70
c337ddc2 MD	71	/*
	72	* Protected by the trace lock.
	73	*/
	74	static struct delayed_work cpu_work[NR_CPUS];
	75	static DECLARE_WAIT_QUEUE_HEAD(statedump_wq);
	76	static atomic_t kernel_threads_to_run;
	77
	78	enum lttng_thread_type {
	79	LTTNG_USER_THREAD = 0,
	80	LTTNG_KERNEL_THREAD = 1,
	81	};
	82
	83	enum lttng_execution_mode {
	84	LTTNG_USER_MODE = 0,
	85	LTTNG_SYSCALL = 1,
	86	LTTNG_TRAP = 2,
	87	LTTNG_IRQ = 3,
	88	LTTNG_SOFTIRQ = 4,
	89	LTTNG_MODE_UNKNOWN = 5,
	90	};
	91
	92	enum lttng_execution_submode {
	93	LTTNG_NONE = 0,
	94	LTTNG_UNKNOWN = 1,
	95	};
	96
	97	enum lttng_process_status {
	98	LTTNG_UNNAMED = 0,
	99	LTTNG_WAIT_FORK = 1,
	100	LTTNG_WAIT_CPU = 2,
	101	LTTNG_EXIT = 3,
	102	LTTNG_ZOMBIE = 4,
	103	LTTNG_WAIT = 5,
	104	LTTNG_RUN = 6,
	105	LTTNG_DEAD = 7,
	106	};
	107
	108	#ifdef CONFIG_INET
	109	static
	110	void lttng_enumerate_device(struct lttng_session *session,
	111	struct net_device *dev)
	112	{
	113	struct in_device *in_dev;
	114	struct in_ifaddr *ifa;
	115
	116	if (dev->flags & IFF_UP) {
	117	in_dev = in_dev_get(dev);
	118	if (in_dev) {
	119	for (ifa = in_dev->ifa_list; ifa != NULL;
	120	ifa = ifa->ifa_next) {
	121	trace_lttng_statedump_network_interface(
	122	session, dev, ifa);
	123	}
	124	in_dev_put(in_dev);
	125	}
	126	} else {
	127	trace_lttng_statedump_network_interface(
	128	session, dev, NULL);
	129	}
	130	}
	131
	132	static
	133	int lttng_enumerate_network_ip_interface(struct lttng_session *session)
	134	{
135	struct net_device *dev;
136
137	read_lock(&dev_base_lock);
138	for_each_netdev(&init_net, dev)
139	lttng_enumerate_device(session, dev);
140	read_unlock(&dev_base_lock);
141
142	return 0;
143	}
144	#else /* CONFIG_INET */
145	static inline
146	int lttng_enumerate_network_ip_interface(struct lttng_session *session)
147	{
148	return 0;
149	}
150	#endif /* CONFIG_INET */
151
361c023a MD	152	static
	153	int lttng_dump_one_fd(const void p, struct file file, unsigned int fd)
	154	{
	155	const struct lttng_fd_ctx *ctx = p;
	156	const char *s = d_path(&file->f_path, ctx->page, PAGE_SIZE);
	157
	158	if (IS_ERR(s)) {
	159	struct dentry *dentry = file->f_path.dentry;
	160
	161	/* Make sure we give at least some info */
	162	spin_lock(&dentry->d_lock);
	163	trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd,
	164	dentry->d_name.name);
	165	spin_unlock(&dentry->d_lock);
	166	goto end;
	167	}
	168	trace_lttng_statedump_file_descriptor(ctx->session, ctx->p, fd, s);
	169	end:
	170	return 0;
	171	}
c337ddc2 MD	172
	173	static
	174	void lttng_enumerate_task_fd(struct lttng_session *session,
	175	struct task_struct p, char tmp)
	176	{
361c023a	177	struct lttng_fd_ctx ctx = { .page = tmp, .session = session, .p = p };
c337ddc2 MD	178
c337ddc2 MD	179	task_lock(p);
361c023a	180	lttng_iterate_fd(p->files, 0, lttng_dump_one_fd, &ctx);
c337ddc2 MD	181	task_unlock(p);
	182	}
	183
	184	static
	185	int lttng_enumerate_file_descriptors(struct lttng_session *session)
	186	{
	187	struct task_struct *p;
	188	char tmp = (char ) __get_free_page(GFP_KERNEL);
	189
	190	/* Enumerate active file descriptors */
	191	rcu_read_lock();
	192	for_each_process(p)
	193	lttng_enumerate_task_fd(session, p, tmp);
	194	rcu_read_unlock();
	195	free_page((unsigned long) tmp);
	196	return 0;
	197	}
	198
0658bdda MD	199	#if 0
	200	/*
	201	* FIXME: we cannot take a mmap_sem while in a RCU read-side critical section
	202	* (scheduling in atomic). Normally, the tasklist lock protects this kind of
	203	* iteration, but it is not exported to modules.
	204	*/
c337ddc2 MD	205	static
	206	void lttng_enumerate_task_vm_maps(struct lttng_session *session,
	207	struct task_struct *p)
	208	{
	209	struct mm_struct *mm;
	210	struct vm_area_struct *map;
	211	unsigned long ino;
	212
	213	/* get_task_mm does a task_lock... */
	214	mm = get_task_mm(p);
	215	if (!mm)
	216	return;
	217
	218	map = mm->mmap;
	219	if (map) {
	220	down_read(&mm->mmap_sem);
	221	while (map) {
	222	if (map->vm_file)
	223	ino = map->vm_file->f_dentry->d_inode->i_ino;
	224	else
	225	ino = 0;
	226	trace_lttng_statedump_vm_map(session, p, map, ino);
	227	map = map->vm_next;
	228	}
	229	up_read(&mm->mmap_sem);
	230	}
	231	mmput(mm);
	232	}
	233
	234	static
	235	int lttng_enumerate_vm_maps(struct lttng_session *session)
	236	{
	237	struct task_struct *p;
	238
	239	rcu_read_lock();
	240	for_each_process(p)
	241	lttng_enumerate_task_vm_maps(session, p);
	242	rcu_read_unlock();
	243	return 0;
	244	}
0658bdda	245	#endif
c337ddc2 MD	246
c337ddc2 MD	247	#ifdef CONFIG_GENERIC_HARDIRQS
47faec4b JN	248
	249	#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,39))
	250	#define irq_desc_get_chip(desc) get_irq_desc_chip(desc)
	251	#endif
	252
c337ddc2 MD	253	static
	254	void lttng_list_interrupts(struct lttng_session *session)
	255	{
	256	unsigned int irq;
	257	unsigned long flags = 0;
	258	struct irq_desc *desc;
	259
	260	#define irq_to_desc wrapper_irq_to_desc
	261	/* needs irq_desc */
	262	for_each_irq_desc(irq, desc) {
	263	struct irqaction *action;
	264	const char *irq_chip_name =
	265	irq_desc_get_chip(desc)->name ? : "unnamed_irq_chip";
	266
	267	local_irq_save(flags);
3a523f5b	268	wrapper_desc_spin_lock(&desc->lock);
c337ddc2 MD	269	for (action = desc->action; action; action = action->next) {
	270	trace_lttng_statedump_interrupt(session,
	271	irq, irq_chip_name, action);
	272	}
3a523f5b	273	wrapper_desc_spin_unlock(&desc->lock);
c337ddc2 MD	274	local_irq_restore(flags);
	275	}
	276	#undef irq_to_desc
	277	}
	278	#else
	279	static inline
	280	void list_interrupts(struct lttng_session *session)
	281	{
	282	}
	283	#endif
	284
73e8ba37 JD	285	static
	286	void lttng_statedump_process_ns(struct lttng_session *session,
	287	struct task_struct *p,
	288	enum lttng_thread_type type,
	289	enum lttng_execution_mode mode,
	290	enum lttng_execution_submode submode,
	291	enum lttng_process_status status)
	292	{
	293	struct nsproxy *proxy;
	294	struct pid_namespace *pid_ns;
	295
	296	rcu_read_lock();
	297	proxy = task_nsproxy(p);
	298	if (proxy) {
3247f8bd	299	pid_ns = lttng_get_proxy_pid_ns(proxy);
73e8ba37 JD	300	do {
	301	trace_lttng_statedump_process_state(session,
	302	p, type, mode, submode, status, pid_ns);
af73f727	303	pid_ns = pid_ns->parent;
73e8ba37 JD	304	} while (pid_ns);
	305	} else {
	306	trace_lttng_statedump_process_state(session,
	307	p, type, mode, submode, status, NULL);
	308	}
	309	rcu_read_unlock();
	310	}
	311
c337ddc2 MD	312	static
	313	int lttng_enumerate_process_states(struct lttng_session *session)
	314	{
	315	struct task_struct g, p;
	316
	317	rcu_read_lock();
	318	for_each_process(g) {
	319	p = g;
	320	do {
	321	enum lttng_execution_mode mode =
	322	LTTNG_MODE_UNKNOWN;
	323	enum lttng_execution_submode submode =
	324	LTTNG_UNKNOWN;
	325	enum lttng_process_status status;
	326	enum lttng_thread_type type;
	327
	328	task_lock(p);
	329	if (p->exit_state == EXIT_ZOMBIE)
	330	status = LTTNG_ZOMBIE;
	331	else if (p->exit_state == EXIT_DEAD)
	332	status = LTTNG_DEAD;
	333	else if (p->state == TASK_RUNNING) {
	334	/* Is this a forked child that has not run yet? */
	335	if (list_empty(&p->rt.run_list))
	336	status = LTTNG_WAIT_FORK;
	337	else
	338	/*
	339	* All tasks are considered as wait_cpu;
	340	* the viewer will sort out if the task
	341	* was really running at this time.
	342	*/
	343	status = LTTNG_WAIT_CPU;
	344	} else if (p->state &
	345	(TASK_INTERRUPTIBLE \| TASK_UNINTERRUPTIBLE)) {
	346	/* Task is waiting for something to complete */
	347	status = LTTNG_WAIT;
	348	} else
	349	status = LTTNG_UNNAMED;
	350	submode = LTTNG_NONE;
	351
	352	/*
	353	* Verification of t->mm is to filter out kernel
	354	* threads; Viewer will further filter out if a
	355	* user-space thread was in syscall mode or not.
	356	*/
	357	if (p->mm)
	358	type = LTTNG_USER_THREAD;
	359	else
	360	type = LTTNG_KERNEL_THREAD;
73e8ba37	361	lttng_statedump_process_ns(session,
c337ddc2 MD	362	p, type, mode, submode, status);
	363	task_unlock(p);
	364	} while_each_thread(g, p);
	365	}
	366	rcu_read_unlock();
	367
	368	return 0;
	369	}
	370
	371	static
	372	void lttng_statedump_work_func(struct work_struct *work)
	373	{
	374	if (atomic_dec_and_test(&kernel_threads_to_run))
	375	/* If we are the last thread, wake up do_lttng_statedump */
	376	wake_up(&statedump_wq);
	377	}
	378
	379	static
	380	int do_lttng_statedump(struct lttng_session *session)
	381	{
	382	int cpu;
	383
c337ddc2 MD	384	trace_lttng_statedump_start(session);
	385	lttng_enumerate_process_states(session);
	386	lttng_enumerate_file_descriptors(session);
0658bdda	387	/* FIXME lttng_enumerate_vm_maps(session); */
c337ddc2 MD	388	lttng_list_interrupts(session);
	389	lttng_enumerate_network_ip_interface(session);
	390
	391	/* TODO lttng_dump_idt_table(session); */
	392	/* TODO lttng_dump_softirq_vec(session); */
	393	/* TODO lttng_list_modules(session); */
	394	/* TODO lttng_dump_swap_files(session); */
	395
	396	/*
	397	* Fire off a work queue on each CPU. Their sole purpose in life
	398	* is to guarantee that each CPU has been in a state where is was in
	399	* syscall mode (i.e. not in a trap, an IRQ or a soft IRQ).
	400	*/
	401	get_online_cpus();
	402	atomic_set(&kernel_threads_to_run, num_online_cpus());
	403	for_each_online_cpu(cpu) {
	404	INIT_DELAYED_WORK(&cpu_work[cpu], lttng_statedump_work_func);
	405	schedule_delayed_work_on(cpu, &cpu_work[cpu], 0);
	406	}
	407	/* Wait for all threads to run */
7a7128e0	408	__wait_event(statedump_wq, (atomic_read(&kernel_threads_to_run) == 0));
c337ddc2 MD	409	put_online_cpus();
c337ddc2 MD	410	/* Our work is done */
c337ddc2 MD	411	trace_lttng_statedump_end(session);
	412	return 0;
	413	}
	414
	415	/*
	416	* Called with session mutex held.
	417	*/
	418	int lttng_statedump_start(struct lttng_session *session)
	419	{
c337ddc2 MD	420	return do_lttng_statedump(session);
	421	}
	422	EXPORT_SYMBOL_GPL(lttng_statedump_start);
	423
	424	MODULE_LICENSE("GPL and additional rights");
	425	MODULE_AUTHOR("Jean-Hugues Deschenes");
	426	MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Statedump");