4 * Linux Trace Toolkit Next Generation Kernel State Dump
6 * Copyright 2005 Jean-Hugues Deschenes <jean-hugues.deschenes@polymtl.ca>
7 * Copyright 2006-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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.
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.
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
24 * Eric Clement: Add listing of network IP interface
25 * 2006, 2007 Mathieu Desnoyers Fix kernel threads
29 #include <linux/init.h>
30 #include <linux/module.h>
31 #include <linux/netlink.h>
32 #include <linux/inet.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>
44 #include <linux/fdtable.h>
45 #include <linux/swap.h>
46 #include <linux/wait.h>
47 #include <linux/mutex.h>
48 #include <linux/device.h>
50 #include "lttng-events.h"
51 #include "lttng-tracer.h"
52 #include "wrapper/irqdesc.h"
53 #include "wrapper/spinlock.h"
54 #include "wrapper/fdtable.h"
55 #include "wrapper/nsproxy.h"
56 #include "wrapper/irq.h"
57 #include "wrapper/tracepoint.h"
58 #include "wrapper/genhd.h"
60 #ifdef CONFIG_LTTNG_HAS_LIST_IRQ
61 #include <linux/irq.h>
64 /* Define the tracepoints, but do not build the probes */
65 #define CREATE_TRACE_POINTS
66 #define TRACE_INCLUDE_PATH ../instrumentation/events/lttng-module
67 #define TRACE_INCLUDE_FILE lttng-statedump
68 #include "instrumentation/events/lttng-module/lttng-statedump.h"
70 DEFINE_TRACE(lttng_statedump_block_device
);
71 DEFINE_TRACE(lttng_statedump_end
);
72 DEFINE_TRACE(lttng_statedump_interrupt
);
73 DEFINE_TRACE(lttng_statedump_file_descriptor
);
74 DEFINE_TRACE(lttng_statedump_start
);
75 DEFINE_TRACE(lttng_statedump_process_state
);
76 DEFINE_TRACE(lttng_statedump_network_interface
);
80 struct lttng_session
*session
;
81 struct task_struct
*p
;
86 * Protected by the trace lock.
88 static struct delayed_work cpu_work
[NR_CPUS
];
89 static DECLARE_WAIT_QUEUE_HEAD(statedump_wq
);
90 static atomic_t kernel_threads_to_run
;
92 enum lttng_thread_type
{
93 LTTNG_USER_THREAD
= 0,
94 LTTNG_KERNEL_THREAD
= 1,
97 enum lttng_execution_mode
{
103 LTTNG_MODE_UNKNOWN
= 5,
106 enum lttng_execution_submode
{
111 enum lttng_process_status
{
123 int lttng_enumerate_block_devices(struct lttng_session
*session
)
125 struct class *ptr_block_class
;
126 struct device_type
*ptr_disk_type
;
127 struct class_dev_iter iter
;
130 ptr_block_class
= wrapper_get_block_class();
131 if (!ptr_block_class
)
133 ptr_disk_type
= wrapper_get_disk_type();
134 if (!ptr_disk_type
) {
137 class_dev_iter_init(&iter
, ptr_block_class
, NULL
, ptr_disk_type
);
138 while ((dev
= class_dev_iter_next(&iter
))) {
139 struct disk_part_iter piter
;
140 struct gendisk
*disk
= dev_to_disk(dev
);
141 struct hd_struct
*part
;
143 disk_part_iter_init(&piter
, disk
, DISK_PITER_INCL_PART0
);
144 while ((part
= disk_part_iter_next(&piter
))) {
145 char name_buf
[BDEVNAME_SIZE
];
148 p
= wrapper_disk_name(disk
, part
->partno
, name_buf
);
150 disk_part_iter_exit(&piter
);
151 class_dev_iter_exit(&iter
);
154 trace_lttng_statedump_block_device(session
,
155 part_devt(part
), name_buf
);
157 disk_part_iter_exit(&piter
);
159 class_dev_iter_exit(&iter
);
166 void lttng_enumerate_device(struct lttng_session
*session
,
167 struct net_device
*dev
)
169 struct in_device
*in_dev
;
170 struct in_ifaddr
*ifa
;
172 if (dev
->flags
& IFF_UP
) {
173 in_dev
= in_dev_get(dev
);
175 for (ifa
= in_dev
->ifa_list
; ifa
!= NULL
;
176 ifa
= ifa
->ifa_next
) {
177 trace_lttng_statedump_network_interface(
183 trace_lttng_statedump_network_interface(
189 int lttng_enumerate_network_ip_interface(struct lttng_session
*session
)
191 struct net_device
*dev
;
193 read_lock(&dev_base_lock
);
194 for_each_netdev(&init_net
, dev
)
195 lttng_enumerate_device(session
, dev
);
196 read_unlock(&dev_base_lock
);
200 #else /* CONFIG_INET */
202 int lttng_enumerate_network_ip_interface(struct lttng_session
*session
)
206 #endif /* CONFIG_INET */
209 int lttng_dump_one_fd(const void *p
, struct file
*file
, unsigned int fd
)
211 const struct lttng_fd_ctx
*ctx
= p
;
212 const char *s
= d_path(&file
->f_path
, ctx
->page
, PAGE_SIZE
);
213 unsigned int flags
= file
->f_flags
;
216 * We don't expose kernel internal flags, only userspace-visible
219 flags
&= ~FMODE_NONOTIFY
;
220 if (test_bit(fd
, ctx
->fdt
->close_on_exec
))
223 struct dentry
*dentry
= file
->f_path
.dentry
;
225 /* Make sure we give at least some info */
226 spin_lock(&dentry
->d_lock
);
227 trace_lttng_statedump_file_descriptor(ctx
->session
, ctx
->p
, fd
,
228 dentry
->d_name
.name
, flags
, file
->f_mode
);
229 spin_unlock(&dentry
->d_lock
);
232 trace_lttng_statedump_file_descriptor(ctx
->session
, ctx
->p
, fd
, s
,
233 flags
, file
->f_mode
);
239 void lttng_enumerate_task_fd(struct lttng_session
*session
,
240 struct task_struct
*p
, char *tmp
)
242 struct lttng_fd_ctx ctx
= { .page
= tmp
, .session
= session
, .p
= p
};
245 ctx
.fdt
= files_fdtable(p
->files
);
246 lttng_iterate_fd(p
->files
, 0, lttng_dump_one_fd
, &ctx
);
251 int lttng_enumerate_file_descriptors(struct lttng_session
*session
)
253 struct task_struct
*p
;
254 char *tmp
= (char *) __get_free_page(GFP_KERNEL
);
256 /* Enumerate active file descriptors */
259 lttng_enumerate_task_fd(session
, p
, tmp
);
261 free_page((unsigned long) tmp
);
267 * FIXME: we cannot take a mmap_sem while in a RCU read-side critical section
268 * (scheduling in atomic). Normally, the tasklist lock protects this kind of
269 * iteration, but it is not exported to modules.
272 void lttng_enumerate_task_vm_maps(struct lttng_session
*session
,
273 struct task_struct
*p
)
275 struct mm_struct
*mm
;
276 struct vm_area_struct
*map
;
279 /* get_task_mm does a task_lock... */
286 down_read(&mm
->mmap_sem
);
289 ino
= map
->vm_file
->f_dentry
->d_inode
->i_ino
;
292 trace_lttng_statedump_vm_map(session
, p
, map
, ino
);
295 up_read(&mm
->mmap_sem
);
301 int lttng_enumerate_vm_maps(struct lttng_session
*session
)
303 struct task_struct
*p
;
307 lttng_enumerate_task_vm_maps(session
, p
);
313 #ifdef CONFIG_LTTNG_HAS_LIST_IRQ
315 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,39))
316 #define irq_desc_get_chip(desc) get_irq_desc_chip(desc)
320 void lttng_list_interrupts(struct lttng_session
*session
)
323 unsigned long flags
= 0;
324 struct irq_desc
*desc
;
326 #define irq_to_desc wrapper_irq_to_desc
328 for_each_irq_desc(irq
, desc
) {
329 struct irqaction
*action
;
330 const char *irq_chip_name
=
331 irq_desc_get_chip(desc
)->name
? : "unnamed_irq_chip";
333 local_irq_save(flags
);
334 wrapper_desc_spin_lock(&desc
->lock
);
335 for (action
= desc
->action
; action
; action
= action
->next
) {
336 trace_lttng_statedump_interrupt(session
,
337 irq
, irq_chip_name
, action
);
339 wrapper_desc_spin_unlock(&desc
->lock
);
340 local_irq_restore(flags
);
346 void lttng_list_interrupts(struct lttng_session
*session
)
352 void lttng_statedump_process_ns(struct lttng_session
*session
,
353 struct task_struct
*p
,
354 enum lttng_thread_type type
,
355 enum lttng_execution_mode mode
,
356 enum lttng_execution_submode submode
,
357 enum lttng_process_status status
)
359 struct nsproxy
*proxy
;
360 struct pid_namespace
*pid_ns
;
363 proxy
= task_nsproxy(p
);
365 pid_ns
= lttng_get_proxy_pid_ns(proxy
);
367 trace_lttng_statedump_process_state(session
,
368 p
, type
, mode
, submode
, status
, pid_ns
);
369 pid_ns
= pid_ns
->parent
;
372 trace_lttng_statedump_process_state(session
,
373 p
, type
, mode
, submode
, status
, NULL
);
379 int lttng_enumerate_process_states(struct lttng_session
*session
)
381 struct task_struct
*g
, *p
;
384 for_each_process(g
) {
387 enum lttng_execution_mode mode
=
389 enum lttng_execution_submode submode
=
391 enum lttng_process_status status
;
392 enum lttng_thread_type type
;
395 if (p
->exit_state
== EXIT_ZOMBIE
)
396 status
= LTTNG_ZOMBIE
;
397 else if (p
->exit_state
== EXIT_DEAD
)
399 else if (p
->state
== TASK_RUNNING
) {
400 /* Is this a forked child that has not run yet? */
401 if (list_empty(&p
->rt
.run_list
))
402 status
= LTTNG_WAIT_FORK
;
405 * All tasks are considered as wait_cpu;
406 * the viewer will sort out if the task
407 * was really running at this time.
409 status
= LTTNG_WAIT_CPU
;
410 } else if (p
->state
&
411 (TASK_INTERRUPTIBLE
| TASK_UNINTERRUPTIBLE
)) {
412 /* Task is waiting for something to complete */
415 status
= LTTNG_UNNAMED
;
416 submode
= LTTNG_NONE
;
419 * Verification of t->mm is to filter out kernel
420 * threads; Viewer will further filter out if a
421 * user-space thread was in syscall mode or not.
424 type
= LTTNG_USER_THREAD
;
426 type
= LTTNG_KERNEL_THREAD
;
427 lttng_statedump_process_ns(session
,
428 p
, type
, mode
, submode
, status
);
430 } while_each_thread(g
, p
);
438 void lttng_statedump_work_func(struct work_struct
*work
)
440 if (atomic_dec_and_test(&kernel_threads_to_run
))
441 /* If we are the last thread, wake up do_lttng_statedump */
442 wake_up(&statedump_wq
);
446 int do_lttng_statedump(struct lttng_session
*session
)
450 trace_lttng_statedump_start(session
);
451 lttng_enumerate_process_states(session
);
452 lttng_enumerate_file_descriptors(session
);
453 /* FIXME lttng_enumerate_vm_maps(session); */
454 lttng_list_interrupts(session
);
455 lttng_enumerate_network_ip_interface(session
);
456 lttng_enumerate_block_devices(session
);
458 /* TODO lttng_dump_idt_table(session); */
459 /* TODO lttng_dump_softirq_vec(session); */
460 /* TODO lttng_list_modules(session); */
461 /* TODO lttng_dump_swap_files(session); */
464 * Fire off a work queue on each CPU. Their sole purpose in life
465 * is to guarantee that each CPU has been in a state where is was in
466 * syscall mode (i.e. not in a trap, an IRQ or a soft IRQ).
469 atomic_set(&kernel_threads_to_run
, num_online_cpus());
470 for_each_online_cpu(cpu
) {
471 INIT_DELAYED_WORK(&cpu_work
[cpu
], lttng_statedump_work_func
);
472 schedule_delayed_work_on(cpu
, &cpu_work
[cpu
], 0);
474 /* Wait for all threads to run */
475 __wait_event(statedump_wq
, (atomic_read(&kernel_threads_to_run
) == 0));
477 /* Our work is done */
478 trace_lttng_statedump_end(session
);
483 * Called with session mutex held.
485 int lttng_statedump_start(struct lttng_session
*session
)
487 return do_lttng_statedump(session
);
489 EXPORT_SYMBOL_GPL(lttng_statedump_start
);
492 int __init
lttng_statedump_init(void)
495 * Allow module to load even if the fixup cannot be done. This
496 * will allow seemless transition when the underlying issue fix
497 * is merged into the Linux kernel, and when tracepoint.c
498 * "tracepoint_module_notify" is turned into a static function.
500 (void) wrapper_lttng_fixup_sig(THIS_MODULE
);
504 module_init(lttng_statedump_init
);
507 void __exit
lttng_statedump_exit(void)
511 module_exit(lttng_statedump_exit
);
513 MODULE_LICENSE("GPL and additional rights");
514 MODULE_AUTHOR("Jean-Hugues Deschenes");
515 MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Statedump");
516 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION
) "."
517 __stringify(LTTNG_MODULES_MINOR_VERSION
) "."
518 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION
)
519 LTTNG_MODULES_EXTRAVERSION
);