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b7cdc182 | 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
9f36eaed | 2 | * |
886d51a3 MD |
3 | * lttng-statedump.c |
4 | * | |
c337ddc2 MD |
5 | * Linux Trace Toolkit Next Generation Kernel State Dump |
6 | * | |
7 | * Copyright 2005 Jean-Hugues Deschenes <jean-hugues.deschenes@polymtl.ca> | |
8 | * Copyright 2006-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
9 | * | |
10 | * Changes: | |
11 | * Eric Clement: Add listing of network IP interface | |
12 | * 2006, 2007 Mathieu Desnoyers Fix kernel threads | |
13 | * Various updates | |
c337ddc2 MD |
14 | */ |
15 | ||
16 | #include <linux/init.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/netlink.h> | |
19 | #include <linux/inet.h> | |
20 | #include <linux/ip.h> | |
21 | #include <linux/kthread.h> | |
22 | #include <linux/proc_fs.h> | |
23 | #include <linux/file.h> | |
24 | #include <linux/interrupt.h> | |
25 | #include <linux/irqnr.h> | |
26 | #include <linux/cpu.h> | |
27 | #include <linux/netdevice.h> | |
28 | #include <linux/inetdevice.h> | |
29 | #include <linux/sched.h> | |
30 | #include <linux/mm.h> | |
c337ddc2 MD |
31 | #include <linux/swap.h> |
32 | #include <linux/wait.h> | |
33 | #include <linux/mutex.h> | |
f0dbdefb | 34 | #include <linux/device.h> |
997eff5e | 35 | #include <linux/fdtable.h> |
88eb3d8e | 36 | #include <linux/irq.h> |
c337ddc2 | 37 | |
241ae9a8 MD |
38 | #include <lttng-events.h> |
39 | #include <lttng-tracer.h> | |
241ae9a8 | 40 | #include <wrapper/genhd.h> |
c337ddc2 | 41 | |
c337ddc2 MD |
42 | /* Define the tracepoints, but do not build the probes */ |
43 | #define CREATE_TRACE_POINTS | |
241ae9a8 | 44 | #define TRACE_INCLUDE_PATH instrumentation/events/lttng-module |
c337ddc2 | 45 | #define TRACE_INCLUDE_FILE lttng-statedump |
3bc29f0a | 46 | #define LTTNG_INSTRUMENTATION |
241ae9a8 | 47 | #include <instrumentation/events/lttng-module/lttng-statedump.h> |
c337ddc2 | 48 | |
f0dbdefb | 49 | DEFINE_TRACE(lttng_statedump_block_device); |
20591cf7 MD |
50 | DEFINE_TRACE(lttng_statedump_end); |
51 | DEFINE_TRACE(lttng_statedump_interrupt); | |
52 | DEFINE_TRACE(lttng_statedump_file_descriptor); | |
53 | DEFINE_TRACE(lttng_statedump_start); | |
54 | DEFINE_TRACE(lttng_statedump_process_state); | |
1965e6b4 MJ |
55 | DEFINE_TRACE(lttng_statedump_process_pid_ns); |
56 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)) | |
57 | DEFINE_TRACE(lttng_statedump_process_cgroup_ns); | |
58 | #endif | |
59 | DEFINE_TRACE(lttng_statedump_process_ipc_ns); | |
60 | #ifndef LTTNG_MNT_NS_MISSING_HEADER | |
61 | DEFINE_TRACE(lttng_statedump_process_mnt_ns); | |
62 | #endif | |
63 | DEFINE_TRACE(lttng_statedump_process_net_ns); | |
64 | DEFINE_TRACE(lttng_statedump_process_user_ns); | |
65 | DEFINE_TRACE(lttng_statedump_process_uts_ns); | |
20591cf7 | 66 | DEFINE_TRACE(lttng_statedump_network_interface); |
d0b55e4c | 67 | #ifdef LTTNG_HAVE_STATEDUMP_CPU_TOPOLOGY |
502e4132 JD |
68 | DEFINE_TRACE(lttng_statedump_cpu_topology); |
69 | #endif | |
20591cf7 | 70 | |
361c023a MD |
71 | struct lttng_fd_ctx { |
72 | char *page; | |
73 | struct lttng_session *session; | |
d561ecfb | 74 | struct files_struct *files; |
361c023a MD |
75 | }; |
76 | ||
c337ddc2 MD |
77 | /* |
78 | * Protected by the trace lock. | |
79 | */ | |
80 | static struct delayed_work cpu_work[NR_CPUS]; | |
81 | static DECLARE_WAIT_QUEUE_HEAD(statedump_wq); | |
82 | static atomic_t kernel_threads_to_run; | |
83 | ||
84 | enum lttng_thread_type { | |
85 | LTTNG_USER_THREAD = 0, | |
86 | LTTNG_KERNEL_THREAD = 1, | |
87 | }; | |
88 | ||
89 | enum lttng_execution_mode { | |
90 | LTTNG_USER_MODE = 0, | |
91 | LTTNG_SYSCALL = 1, | |
92 | LTTNG_TRAP = 2, | |
93 | LTTNG_IRQ = 3, | |
94 | LTTNG_SOFTIRQ = 4, | |
95 | LTTNG_MODE_UNKNOWN = 5, | |
96 | }; | |
97 | ||
98 | enum lttng_execution_submode { | |
99 | LTTNG_NONE = 0, | |
100 | LTTNG_UNKNOWN = 1, | |
101 | }; | |
102 | ||
103 | enum lttng_process_status { | |
104 | LTTNG_UNNAMED = 0, | |
105 | LTTNG_WAIT_FORK = 1, | |
106 | LTTNG_WAIT_CPU = 2, | |
107 | LTTNG_EXIT = 3, | |
108 | LTTNG_ZOMBIE = 4, | |
109 | LTTNG_WAIT = 5, | |
110 | LTTNG_RUN = 6, | |
111 | LTTNG_DEAD = 7, | |
112 | }; | |
113 | ||
f0dbdefb HD |
114 | static |
115 | int lttng_enumerate_block_devices(struct lttng_session *session) | |
116 | { | |
117 | struct class *ptr_block_class; | |
118 | struct device_type *ptr_disk_type; | |
119 | struct class_dev_iter iter; | |
120 | struct device *dev; | |
121 | ||
122 | ptr_block_class = wrapper_get_block_class(); | |
123 | if (!ptr_block_class) | |
124 | return -ENOSYS; | |
125 | ptr_disk_type = wrapper_get_disk_type(); | |
126 | if (!ptr_disk_type) { | |
127 | return -ENOSYS; | |
128 | } | |
129 | class_dev_iter_init(&iter, ptr_block_class, NULL, ptr_disk_type); | |
130 | while ((dev = class_dev_iter_next(&iter))) { | |
131 | struct disk_part_iter piter; | |
132 | struct gendisk *disk = dev_to_disk(dev); | |
133 | struct hd_struct *part; | |
134 | ||
5a91f3df MD |
135 | /* |
136 | * Don't show empty devices or things that have been | |
137 | * suppressed | |
138 | */ | |
139 | if (get_capacity(disk) == 0 || | |
140 | (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)) | |
141 | continue; | |
142 | ||
f0dbdefb HD |
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]; | |
146 | char *p; | |
147 | ||
148 | p = wrapper_disk_name(disk, part->partno, name_buf); | |
149 | if (!p) { | |
150 | disk_part_iter_exit(&piter); | |
151 | class_dev_iter_exit(&iter); | |
152 | return -ENOSYS; | |
153 | } | |
154 | trace_lttng_statedump_block_device(session, | |
155 | part_devt(part), name_buf); | |
156 | } | |
157 | disk_part_iter_exit(&piter); | |
158 | } | |
159 | class_dev_iter_exit(&iter); | |
160 | return 0; | |
161 | } | |
162 | ||
c337ddc2 | 163 | #ifdef CONFIG_INET |
f0dbdefb | 164 | |
c337ddc2 MD |
165 | static |
166 | void lttng_enumerate_device(struct lttng_session *session, | |
167 | struct net_device *dev) | |
168 | { | |
169 | struct in_device *in_dev; | |
170 | struct in_ifaddr *ifa; | |
171 | ||
172 | if (dev->flags & IFF_UP) { | |
173 | in_dev = in_dev_get(dev); | |
174 | if (in_dev) { | |
175 | for (ifa = in_dev->ifa_list; ifa != NULL; | |
176 | ifa = ifa->ifa_next) { | |
177 | trace_lttng_statedump_network_interface( | |
178 | session, dev, ifa); | |
179 | } | |
180 | in_dev_put(in_dev); | |
181 | } | |
182 | } else { | |
183 | trace_lttng_statedump_network_interface( | |
184 | session, dev, NULL); | |
185 | } | |
186 | } | |
187 | ||
188 | static | |
189 | int lttng_enumerate_network_ip_interface(struct lttng_session *session) | |
190 | { | |
191 | struct net_device *dev; | |
192 | ||
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); | |
197 | ||
198 | return 0; | |
199 | } | |
200 | #else /* CONFIG_INET */ | |
201 | static inline | |
202 | int lttng_enumerate_network_ip_interface(struct lttng_session *session) | |
203 | { | |
204 | return 0; | |
205 | } | |
206 | #endif /* CONFIG_INET */ | |
207 | ||
361c023a MD |
208 | static |
209 | int lttng_dump_one_fd(const void *p, struct file *file, unsigned int fd) | |
210 | { | |
211 | const struct lttng_fd_ctx *ctx = p; | |
212 | const char *s = d_path(&file->f_path, ctx->page, PAGE_SIZE); | |
29021503 | 213 | unsigned int flags = file->f_flags; |
d561ecfb | 214 | struct fdtable *fdt; |
361c023a | 215 | |
29021503 MD |
216 | /* |
217 | * We don't expose kernel internal flags, only userspace-visible | |
218 | * flags. | |
219 | */ | |
220 | flags &= ~FMODE_NONOTIFY; | |
d561ecfb MD |
221 | fdt = files_fdtable(ctx->files); |
222 | /* | |
223 | * We need to check here again whether fd is within the fdt | |
224 | * max_fds range, because we might be seeing a different | |
225 | * files_fdtable() than iterate_fd(), assuming only RCU is | |
226 | * protecting the read. In reality, iterate_fd() holds | |
227 | * file_lock, which should ensure the fdt does not change while | |
228 | * the lock is taken, but we are not aware whether this is | |
229 | * guaranteed or not, so play safe. | |
230 | */ | |
997eff5e | 231 | if (fd < fdt->max_fds && close_on_exec(fd, fdt)) |
29021503 | 232 | flags |= O_CLOEXEC; |
361c023a MD |
233 | if (IS_ERR(s)) { |
234 | struct dentry *dentry = file->f_path.dentry; | |
235 | ||
236 | /* Make sure we give at least some info */ | |
237 | spin_lock(&dentry->d_lock); | |
e7a0ca72 MD |
238 | trace_lttng_statedump_file_descriptor(ctx->session, |
239 | ctx->files, fd, dentry->d_name.name, flags, | |
240 | file->f_mode); | |
361c023a MD |
241 | spin_unlock(&dentry->d_lock); |
242 | goto end; | |
243 | } | |
e7a0ca72 MD |
244 | trace_lttng_statedump_file_descriptor(ctx->session, |
245 | ctx->files, fd, s, flags, file->f_mode); | |
361c023a MD |
246 | end: |
247 | return 0; | |
248 | } | |
c337ddc2 | 249 | |
e7a0ca72 | 250 | /* Called with task lock held. */ |
c337ddc2 | 251 | static |
e7a0ca72 MD |
252 | void lttng_enumerate_files(struct lttng_session *session, |
253 | struct files_struct *files, | |
254 | char *tmp) | |
c337ddc2 | 255 | { |
e7a0ca72 | 256 | struct lttng_fd_ctx ctx = { .page = tmp, .session = session, .files = files, }; |
c337ddc2 | 257 | |
997eff5e | 258 | iterate_fd(files, 0, lttng_dump_one_fd, &ctx); |
c337ddc2 MD |
259 | } |
260 | ||
d0b55e4c | 261 | #ifdef LTTNG_HAVE_STATEDUMP_CPU_TOPOLOGY |
502e4132 JD |
262 | static |
263 | int lttng_enumerate_cpu_topology(struct lttng_session *session) | |
264 | { | |
265 | int cpu; | |
266 | const cpumask_t *cpumask = cpu_possible_mask; | |
267 | ||
268 | for (cpu = cpumask_first(cpumask); cpu < nr_cpu_ids; | |
269 | cpu = cpumask_next(cpu, cpumask)) { | |
270 | trace_lttng_statedump_cpu_topology(session, &cpu_data(cpu)); | |
271 | } | |
272 | ||
273 | return 0; | |
274 | } | |
275 | #else | |
276 | static | |
277 | int lttng_enumerate_cpu_topology(struct lttng_session *session) | |
278 | { | |
279 | return 0; | |
280 | } | |
281 | #endif | |
282 | ||
0658bdda MD |
283 | #if 0 |
284 | /* | |
285 | * FIXME: we cannot take a mmap_sem while in a RCU read-side critical section | |
286 | * (scheduling in atomic). Normally, the tasklist lock protects this kind of | |
287 | * iteration, but it is not exported to modules. | |
288 | */ | |
c337ddc2 MD |
289 | static |
290 | void lttng_enumerate_task_vm_maps(struct lttng_session *session, | |
291 | struct task_struct *p) | |
292 | { | |
293 | struct mm_struct *mm; | |
294 | struct vm_area_struct *map; | |
295 | unsigned long ino; | |
296 | ||
297 | /* get_task_mm does a task_lock... */ | |
298 | mm = get_task_mm(p); | |
299 | if (!mm) | |
300 | return; | |
301 | ||
302 | map = mm->mmap; | |
303 | if (map) { | |
304 | down_read(&mm->mmap_sem); | |
305 | while (map) { | |
306 | if (map->vm_file) | |
34522739 | 307 | ino = map->vm_file->f_path.dentry->d_inode->i_ino; |
c337ddc2 MD |
308 | else |
309 | ino = 0; | |
310 | trace_lttng_statedump_vm_map(session, p, map, ino); | |
311 | map = map->vm_next; | |
312 | } | |
313 | up_read(&mm->mmap_sem); | |
314 | } | |
315 | mmput(mm); | |
316 | } | |
317 | ||
318 | static | |
319 | int lttng_enumerate_vm_maps(struct lttng_session *session) | |
320 | { | |
321 | struct task_struct *p; | |
322 | ||
323 | rcu_read_lock(); | |
324 | for_each_process(p) | |
325 | lttng_enumerate_task_vm_maps(session, p); | |
326 | rcu_read_unlock(); | |
327 | return 0; | |
328 | } | |
0658bdda | 329 | #endif |
c337ddc2 | 330 | |
c337ddc2 | 331 | static |
cfcee1c7 | 332 | int lttng_list_interrupts(struct lttng_session *session) |
c337ddc2 MD |
333 | { |
334 | unsigned int irq; | |
335 | unsigned long flags = 0; | |
336 | struct irq_desc *desc; | |
337 | ||
c337ddc2 MD |
338 | /* needs irq_desc */ |
339 | for_each_irq_desc(irq, desc) { | |
340 | struct irqaction *action; | |
341 | const char *irq_chip_name = | |
342 | irq_desc_get_chip(desc)->name ? : "unnamed_irq_chip"; | |
343 | ||
344 | local_irq_save(flags); | |
fc94c945 | 345 | raw_spin_lock(&desc->lock); |
c337ddc2 MD |
346 | for (action = desc->action; action; action = action->next) { |
347 | trace_lttng_statedump_interrupt(session, | |
348 | irq, irq_chip_name, action); | |
349 | } | |
fc94c945 | 350 | raw_spin_unlock(&desc->lock); |
c337ddc2 MD |
351 | local_irq_restore(flags); |
352 | } | |
cfcee1c7 | 353 | return 0; |
c337ddc2 | 354 | } |
c337ddc2 | 355 | |
4ba1f53c | 356 | /* |
1965e6b4 MJ |
357 | * Statedump the task's namespaces using the proc filesystem inode number as |
358 | * the unique identifier. The user and pid ns are nested and will be dumped | |
359 | * recursively. | |
360 | * | |
4ba1f53c MD |
361 | * Called with task lock held. |
362 | */ | |
73e8ba37 JD |
363 | static |
364 | void lttng_statedump_process_ns(struct lttng_session *session, | |
365 | struct task_struct *p, | |
366 | enum lttng_thread_type type, | |
367 | enum lttng_execution_mode mode, | |
368 | enum lttng_execution_submode submode, | |
369 | enum lttng_process_status status) | |
370 | { | |
1965e6b4 | 371 | struct nsproxy *proxy; |
73e8ba37 | 372 | struct pid_namespace *pid_ns; |
1965e6b4 | 373 | struct user_namespace *user_ns; |
73e8ba37 | 374 | |
1965e6b4 MJ |
375 | /* |
376 | * The pid and user namespaces are special, they are nested and | |
377 | * accessed with specific functions instead of the nsproxy struct | |
378 | * like the other namespaces. | |
379 | */ | |
887bcdac MJ |
380 | pid_ns = task_active_pid_ns(p); |
381 | do { | |
1965e6b4 | 382 | trace_lttng_statedump_process_pid_ns(session, p, pid_ns); |
adcc8b5e | 383 | pid_ns = pid_ns ? pid_ns->parent : NULL; |
887bcdac | 384 | } while (pid_ns); |
1965e6b4 MJ |
385 | |
386 | ||
387 | user_ns = task_cred_xxx(p, user_ns); | |
388 | do { | |
389 | trace_lttng_statedump_process_user_ns(session, p, user_ns); | |
1964cccb MD |
390 | /* |
391 | * trace_lttng_statedump_process_user_ns() internally | |
392 | * checks whether user_ns is NULL. While this does not | |
393 | * appear to be a possible return value for | |
394 | * task_cred_xxx(), err on the safe side and check | |
395 | * for NULL here as well to be consistent with the | |
396 | * paranoid behavior of | |
397 | * trace_lttng_statedump_process_user_ns(). | |
398 | */ | |
6388029c | 399 | user_ns = user_ns ? user_ns->parent : NULL; |
1965e6b4 MJ |
400 | } while (user_ns); |
401 | ||
402 | /* | |
403 | * Back and forth on locking strategy within Linux upstream for nsproxy. | |
404 | * See Linux upstream commit 728dba3a39c66b3d8ac889ddbe38b5b1c264aec3 | |
405 | * "namespaces: Use task_lock and not rcu to protect nsproxy" | |
406 | * for details. | |
407 | */ | |
408 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) || \ | |
409 | LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,36, 3,14,0,0) || \ | |
410 | LTTNG_UBUNTU_KERNEL_RANGE(3,16,1,11, 3,17,0,0) || \ | |
411 | LTTNG_RHEL_KERNEL_RANGE(3,10,0,229,13,0, 3,11,0,0,0,0)) | |
412 | proxy = p->nsproxy; | |
413 | #else | |
414 | rcu_read_lock(); | |
415 | proxy = task_nsproxy(p); | |
416 | #endif | |
417 | if (proxy) { | |
418 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)) | |
419 | trace_lttng_statedump_process_cgroup_ns(session, p, proxy->cgroup_ns); | |
420 | #endif | |
421 | trace_lttng_statedump_process_ipc_ns(session, p, proxy->ipc_ns); | |
422 | #ifndef LTTNG_MNT_NS_MISSING_HEADER | |
423 | trace_lttng_statedump_process_mnt_ns(session, p, proxy->mnt_ns); | |
424 | #endif | |
425 | trace_lttng_statedump_process_net_ns(session, p, proxy->net_ns); | |
426 | trace_lttng_statedump_process_uts_ns(session, p, proxy->uts_ns); | |
427 | } | |
428 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) || \ | |
429 | LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,36, 3,14,0,0) || \ | |
430 | LTTNG_UBUNTU_KERNEL_RANGE(3,16,1,11, 3,17,0,0) || \ | |
431 | LTTNG_RHEL_KERNEL_RANGE(3,10,0,229,13,0, 3,11,0,0,0,0)) | |
432 | /* (nothing) */ | |
433 | #else | |
434 | rcu_read_unlock(); | |
435 | #endif | |
73e8ba37 JD |
436 | } |
437 | ||
c337ddc2 MD |
438 | static |
439 | int lttng_enumerate_process_states(struct lttng_session *session) | |
440 | { | |
441 | struct task_struct *g, *p; | |
e7a0ca72 MD |
442 | char *tmp; |
443 | ||
444 | tmp = (char *) __get_free_page(GFP_KERNEL); | |
445 | if (!tmp) | |
446 | return -ENOMEM; | |
c337ddc2 MD |
447 | |
448 | rcu_read_lock(); | |
449 | for_each_process(g) { | |
e7a0ca72 MD |
450 | struct files_struct *prev_files = NULL; |
451 | ||
c337ddc2 MD |
452 | p = g; |
453 | do { | |
454 | enum lttng_execution_mode mode = | |
455 | LTTNG_MODE_UNKNOWN; | |
456 | enum lttng_execution_submode submode = | |
457 | LTTNG_UNKNOWN; | |
458 | enum lttng_process_status status; | |
459 | enum lttng_thread_type type; | |
e7a0ca72 | 460 | struct files_struct *files; |
c337ddc2 MD |
461 | |
462 | task_lock(p); | |
463 | if (p->exit_state == EXIT_ZOMBIE) | |
464 | status = LTTNG_ZOMBIE; | |
465 | else if (p->exit_state == EXIT_DEAD) | |
466 | status = LTTNG_DEAD; | |
467 | else if (p->state == TASK_RUNNING) { | |
468 | /* Is this a forked child that has not run yet? */ | |
469 | if (list_empty(&p->rt.run_list)) | |
470 | status = LTTNG_WAIT_FORK; | |
471 | else | |
472 | /* | |
473 | * All tasks are considered as wait_cpu; | |
474 | * the viewer will sort out if the task | |
475 | * was really running at this time. | |
476 | */ | |
477 | status = LTTNG_WAIT_CPU; | |
478 | } else if (p->state & | |
479 | (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)) { | |
480 | /* Task is waiting for something to complete */ | |
481 | status = LTTNG_WAIT; | |
482 | } else | |
483 | status = LTTNG_UNNAMED; | |
484 | submode = LTTNG_NONE; | |
485 | ||
486 | /* | |
487 | * Verification of t->mm is to filter out kernel | |
488 | * threads; Viewer will further filter out if a | |
489 | * user-space thread was in syscall mode or not. | |
490 | */ | |
491 | if (p->mm) | |
492 | type = LTTNG_USER_THREAD; | |
493 | else | |
494 | type = LTTNG_KERNEL_THREAD; | |
e7a0ca72 | 495 | files = p->files; |
d2a927ac MJ |
496 | |
497 | trace_lttng_statedump_process_state(session, | |
e7a0ca72 | 498 | p, type, mode, submode, status, files); |
73e8ba37 | 499 | lttng_statedump_process_ns(session, |
c337ddc2 | 500 | p, type, mode, submode, status); |
e7a0ca72 MD |
501 | /* |
502 | * As an optimisation for the common case, do not | |
503 | * repeat information for the same files_struct in | |
504 | * two consecutive threads. This is the common case | |
505 | * for threads sharing the same fd table. RCU guarantees | |
506 | * that the same files_struct pointer is not re-used | |
507 | * throughout processes/threads iteration. | |
508 | */ | |
509 | if (files && files != prev_files) { | |
510 | lttng_enumerate_files(session, files, tmp); | |
511 | prev_files = files; | |
512 | } | |
c337ddc2 MD |
513 | task_unlock(p); |
514 | } while_each_thread(g, p); | |
515 | } | |
516 | rcu_read_unlock(); | |
517 | ||
e7a0ca72 MD |
518 | free_page((unsigned long) tmp); |
519 | ||
c337ddc2 MD |
520 | return 0; |
521 | } | |
522 | ||
523 | static | |
524 | void lttng_statedump_work_func(struct work_struct *work) | |
525 | { | |
526 | if (atomic_dec_and_test(&kernel_threads_to_run)) | |
527 | /* If we are the last thread, wake up do_lttng_statedump */ | |
528 | wake_up(&statedump_wq); | |
529 | } | |
530 | ||
531 | static | |
532 | int do_lttng_statedump(struct lttng_session *session) | |
533 | { | |
cfcee1c7 | 534 | int cpu, ret; |
c337ddc2 | 535 | |
c337ddc2 | 536 | trace_lttng_statedump_start(session); |
cfcee1c7 | 537 | ret = lttng_enumerate_process_states(session); |
cfcee1c7 MD |
538 | if (ret) |
539 | return ret; | |
540 | /* | |
541 | * FIXME | |
542 | * ret = lttng_enumerate_vm_maps(session); | |
543 | * if (ret) | |
544 | * return ret; | |
545 | */ | |
546 | ret = lttng_list_interrupts(session); | |
547 | if (ret) | |
548 | return ret; | |
549 | ret = lttng_enumerate_network_ip_interface(session); | |
550 | if (ret) | |
551 | return ret; | |
552 | ret = lttng_enumerate_block_devices(session); | |
553 | switch (ret) { | |
84c7055e MD |
554 | case 0: |
555 | break; | |
cfcee1c7 MD |
556 | case -ENOSYS: |
557 | printk(KERN_WARNING "LTTng: block device enumeration is not supported by kernel\n"); | |
558 | break; | |
559 | default: | |
560 | return ret; | |
561 | } | |
502e4132 JD |
562 | ret = lttng_enumerate_cpu_topology(session); |
563 | if (ret) | |
564 | return ret; | |
c337ddc2 MD |
565 | |
566 | /* TODO lttng_dump_idt_table(session); */ | |
567 | /* TODO lttng_dump_softirq_vec(session); */ | |
568 | /* TODO lttng_list_modules(session); */ | |
569 | /* TODO lttng_dump_swap_files(session); */ | |
570 | ||
571 | /* | |
572 | * Fire off a work queue on each CPU. Their sole purpose in life | |
573 | * is to guarantee that each CPU has been in a state where is was in | |
574 | * syscall mode (i.e. not in a trap, an IRQ or a soft IRQ). | |
575 | */ | |
576 | get_online_cpus(); | |
577 | atomic_set(&kernel_threads_to_run, num_online_cpus()); | |
578 | for_each_online_cpu(cpu) { | |
579 | INIT_DELAYED_WORK(&cpu_work[cpu], lttng_statedump_work_func); | |
580 | schedule_delayed_work_on(cpu, &cpu_work[cpu], 0); | |
581 | } | |
582 | /* Wait for all threads to run */ | |
7a7128e0 | 583 | __wait_event(statedump_wq, (atomic_read(&kernel_threads_to_run) == 0)); |
c337ddc2 MD |
584 | put_online_cpus(); |
585 | /* Our work is done */ | |
c337ddc2 MD |
586 | trace_lttng_statedump_end(session); |
587 | return 0; | |
588 | } | |
589 | ||
590 | /* | |
591 | * Called with session mutex held. | |
592 | */ | |
593 | int lttng_statedump_start(struct lttng_session *session) | |
594 | { | |
c337ddc2 MD |
595 | return do_lttng_statedump(session); |
596 | } | |
597 | EXPORT_SYMBOL_GPL(lttng_statedump_start); | |
598 | ||
dd8d5afb MD |
599 | static |
600 | int __init lttng_statedump_init(void) | |
601 | { | |
d16aa9c9 | 602 | return 0; |
dd8d5afb MD |
603 | } |
604 | ||
605 | module_init(lttng_statedump_init); | |
606 | ||
461277e7 MD |
607 | static |
608 | void __exit lttng_statedump_exit(void) | |
609 | { | |
610 | } | |
611 | ||
612 | module_exit(lttng_statedump_exit); | |
613 | ||
c337ddc2 MD |
614 | MODULE_LICENSE("GPL and additional rights"); |
615 | MODULE_AUTHOR("Jean-Hugues Deschenes"); | |
1c124020 | 616 | MODULE_DESCRIPTION("LTTng statedump provider"); |
13ab8b0a MD |
617 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
618 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
619 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) | |
620 | LTTNG_MODULES_EXTRAVERSION); |