]>
Commit | Line | Data |
---|---|---|
6714d8e8 KH |
1 | /* -*- mode: c; c-basic-offset: 8; -*- |
2 | * vim: noexpandtab sw=8 ts=8 sts=0: | |
3 | * | |
4 | * dlmthread.c | |
5 | * | |
6 | * standalone DLM module | |
7 | * | |
8 | * Copyright (C) 2004 Oracle. All rights reserved. | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public | |
12 | * License as published by the Free Software Foundation; either | |
13 | * version 2 of the License, or (at your option) any later version. | |
14 | * | |
15 | * This program is distributed in the hope that it will be useful, | |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
18 | * General Public License for more details. | |
19 | * | |
20 | * You should have received a copy of the GNU General Public | |
21 | * License along with this program; if not, write to the | |
22 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
23 | * Boston, MA 021110-1307, USA. | |
24 | * | |
25 | */ | |
26 | ||
27 | ||
28 | #include <linux/module.h> | |
29 | #include <linux/fs.h> | |
30 | #include <linux/types.h> | |
6714d8e8 | 31 | #include <linux/highmem.h> |
6714d8e8 KH |
32 | #include <linux/init.h> |
33 | #include <linux/sysctl.h> | |
34 | #include <linux/random.h> | |
35 | #include <linux/blkdev.h> | |
36 | #include <linux/socket.h> | |
37 | #include <linux/inet.h> | |
38 | #include <linux/timer.h> | |
39 | #include <linux/kthread.h> | |
8d79d088 | 40 | #include <linux/delay.h> |
6714d8e8 KH |
41 | |
42 | ||
43 | #include "cluster/heartbeat.h" | |
44 | #include "cluster/nodemanager.h" | |
45 | #include "cluster/tcp.h" | |
46 | ||
47 | #include "dlmapi.h" | |
48 | #include "dlmcommon.h" | |
49 | #include "dlmdomain.h" | |
50 | ||
51 | #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_THREAD) | |
52 | #include "cluster/masklog.h" | |
53 | ||
6714d8e8 | 54 | static int dlm_thread(void *data); |
6714d8e8 KH |
55 | static void dlm_flush_asts(struct dlm_ctxt *dlm); |
56 | ||
57 | #define dlm_lock_is_remote(dlm, lock) ((lock)->ml.node != (dlm)->node_num) | |
58 | ||
59 | /* will exit holding res->spinlock, but may drop in function */ | |
60 | /* waits until flags are cleared on res->state */ | |
61 | void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags) | |
62 | { | |
63 | DECLARE_WAITQUEUE(wait, current); | |
64 | ||
65 | assert_spin_locked(&res->spinlock); | |
66 | ||
67 | add_wait_queue(&res->wq, &wait); | |
68 | repeat: | |
69 | set_current_state(TASK_UNINTERRUPTIBLE); | |
70 | if (res->state & flags) { | |
71 | spin_unlock(&res->spinlock); | |
72 | schedule(); | |
73 | spin_lock(&res->spinlock); | |
74 | goto repeat; | |
75 | } | |
76 | remove_wait_queue(&res->wq, &wait); | |
5c2c9d38 | 77 | __set_current_state(TASK_RUNNING); |
6714d8e8 KH |
78 | } |
79 | ||
ba2bf218 | 80 | int __dlm_lockres_has_locks(struct dlm_lock_resource *res) |
6714d8e8 KH |
81 | { |
82 | if (list_empty(&res->granted) && | |
83 | list_empty(&res->converting) && | |
ba2bf218 KH |
84 | list_empty(&res->blocked)) |
85 | return 0; | |
86 | return 1; | |
87 | } | |
88 | ||
89 | /* "unused": the lockres has no locks, is not on the dirty list, | |
90 | * has no inflight locks (in the gap between mastery and acquiring | |
91 | * the first lock), and has no bits in its refmap. | |
92 | * truly ready to be freed. */ | |
93 | int __dlm_lockres_unused(struct dlm_lock_resource *res) | |
94 | { | |
a524812b WW |
95 | int bit; |
96 | ||
97 | if (__dlm_lockres_has_locks(res)) | |
98 | return 0; | |
99 | ||
100 | if (!list_empty(&res->dirty) || res->state & DLM_LOCK_RES_DIRTY) | |
101 | return 0; | |
102 | ||
103 | if (res->state & DLM_LOCK_RES_RECOVERING) | |
104 | return 0; | |
105 | ||
106 | bit = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); | |
107 | if (bit < O2NM_MAX_NODES) | |
108 | return 0; | |
109 | ||
110 | /* | |
111 | * since the bit for dlm->node_num is not set, inflight_locks better | |
112 | * be zero | |
113 | */ | |
114 | BUG_ON(res->inflight_locks != 0); | |
115 | return 1; | |
6714d8e8 KH |
116 | } |
117 | ||
118 | ||
119 | /* Call whenever you may have added or deleted something from one of | |
120 | * the lockres queue's. This will figure out whether it belongs on the | |
121 | * unused list or not and does the appropriate thing. */ | |
122 | void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm, | |
123 | struct dlm_lock_resource *res) | |
124 | { | |
125 | mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); | |
126 | ||
127 | assert_spin_locked(&dlm->spinlock); | |
128 | assert_spin_locked(&res->spinlock); | |
129 | ||
130 | if (__dlm_lockres_unused(res)){ | |
131 | if (list_empty(&res->purge)) { | |
ba2bf218 KH |
132 | mlog(0, "putting lockres %.*s:%p onto purge list\n", |
133 | res->lockname.len, res->lockname.name, res); | |
6714d8e8 KH |
134 | |
135 | res->last_used = jiffies; | |
ba2bf218 | 136 | dlm_lockres_get(res); |
6714d8e8 KH |
137 | list_add_tail(&res->purge, &dlm->purge_list); |
138 | dlm->purge_count++; | |
139 | } | |
140 | } else if (!list_empty(&res->purge)) { | |
ba2bf218 KH |
141 | mlog(0, "removing lockres %.*s:%p from purge list, owner=%u\n", |
142 | res->lockname.len, res->lockname.name, res, res->owner); | |
6714d8e8 KH |
143 | |
144 | list_del_init(&res->purge); | |
ba2bf218 | 145 | dlm_lockres_put(res); |
6714d8e8 KH |
146 | dlm->purge_count--; |
147 | } | |
148 | } | |
149 | ||
150 | void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, | |
151 | struct dlm_lock_resource *res) | |
152 | { | |
153 | mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); | |
154 | spin_lock(&dlm->spinlock); | |
155 | spin_lock(&res->spinlock); | |
156 | ||
157 | __dlm_lockres_calc_usage(dlm, res); | |
158 | ||
159 | spin_unlock(&res->spinlock); | |
160 | spin_unlock(&dlm->spinlock); | |
161 | } | |
162 | ||
7beaf243 | 163 | static void dlm_purge_lockres(struct dlm_ctxt *dlm, |
faf0ec9f | 164 | struct dlm_lock_resource *res) |
6714d8e8 KH |
165 | { |
166 | int master; | |
ba2bf218 | 167 | int ret = 0; |
6714d8e8 | 168 | |
7beaf243 SE |
169 | assert_spin_locked(&dlm->spinlock); |
170 | assert_spin_locked(&res->spinlock); | |
516b7e52 | 171 | |
ba2bf218 | 172 | master = (res->owner == dlm->node_num); |
516b7e52 | 173 | |
6714d8e8 | 174 | |
ba2bf218 KH |
175 | mlog(0, "purging lockres %.*s, master = %d\n", res->lockname.len, |
176 | res->lockname.name, master); | |
177 | ||
178 | if (!master) { | |
7beaf243 | 179 | res->state |= DLM_LOCK_RES_DROPPING_REF; |
c824c3c7 | 180 | /* drop spinlock... retake below */ |
7beaf243 | 181 | spin_unlock(&res->spinlock); |
c824c3c7 SM |
182 | spin_unlock(&dlm->spinlock); |
183 | ||
3b8118cf KH |
184 | spin_lock(&res->spinlock); |
185 | /* This ensures that clear refmap is sent after the set */ | |
7dc102b7 | 186 | __dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG); |
3b8118cf | 187 | spin_unlock(&res->spinlock); |
c824c3c7 | 188 | |
ba2bf218 KH |
189 | /* clear our bit from the master's refmap, ignore errors */ |
190 | ret = dlm_drop_lockres_ref(dlm, res); | |
191 | if (ret < 0) { | |
192 | mlog_errno(ret); | |
193 | if (!dlm_is_host_down(ret)) | |
194 | BUG(); | |
195 | } | |
196 | mlog(0, "%s:%.*s: dlm_deref_lockres returned %d\n", | |
197 | dlm->name, res->lockname.len, res->lockname.name, ret); | |
198 | spin_lock(&dlm->spinlock); | |
7beaf243 | 199 | spin_lock(&res->spinlock); |
6714d8e8 KH |
200 | } |
201 | ||
ba2bf218 KH |
202 | if (!list_empty(&res->purge)) { |
203 | mlog(0, "removing lockres %.*s:%p from purgelist, " | |
204 | "master = %d\n", res->lockname.len, res->lockname.name, | |
205 | res, master); | |
206 | list_del_init(&res->purge); | |
207 | dlm_lockres_put(res); | |
6714d8e8 | 208 | dlm->purge_count--; |
7beaf243 SE |
209 | } |
210 | ||
211 | if (!__dlm_lockres_unused(res)) { | |
212 | mlog(ML_ERROR, "found lockres %s:%.*s: in use after deref\n", | |
213 | dlm->name, res->lockname.len, res->lockname.name); | |
214 | __dlm_print_one_lock_resource(res); | |
215 | BUG(); | |
216 | } | |
83e32d90 | 217 | |
ba2bf218 | 218 | __dlm_unhash_lockres(res); |
6714d8e8 | 219 | |
ba2bf218 KH |
220 | /* lockres is not in the hash now. drop the flag and wake up |
221 | * any processes waiting in dlm_get_lock_resource. */ | |
222 | if (!master) { | |
ba2bf218 KH |
223 | res->state &= ~DLM_LOCK_RES_DROPPING_REF; |
224 | spin_unlock(&res->spinlock); | |
225 | wake_up(&res->wq); | |
7beaf243 SE |
226 | } else |
227 | spin_unlock(&res->spinlock); | |
8b219809 KH |
228 | } |
229 | ||
6714d8e8 KH |
230 | static void dlm_run_purge_list(struct dlm_ctxt *dlm, |
231 | int purge_now) | |
232 | { | |
233 | unsigned int run_max, unused; | |
234 | unsigned long purge_jiffies; | |
235 | struct dlm_lock_resource *lockres; | |
236 | ||
237 | spin_lock(&dlm->spinlock); | |
238 | run_max = dlm->purge_count; | |
239 | ||
240 | while(run_max && !list_empty(&dlm->purge_list)) { | |
241 | run_max--; | |
242 | ||
243 | lockres = list_entry(dlm->purge_list.next, | |
244 | struct dlm_lock_resource, purge); | |
245 | ||
6714d8e8 | 246 | spin_lock(&lockres->spinlock); |
6714d8e8 KH |
247 | |
248 | purge_jiffies = lockres->last_used + | |
249 | msecs_to_jiffies(DLM_PURGE_INTERVAL_MS); | |
250 | ||
251 | /* Make sure that we want to be processing this guy at | |
252 | * this time. */ | |
253 | if (!purge_now && time_after(purge_jiffies, jiffies)) { | |
254 | /* Since resources are added to the purge list | |
255 | * in tail order, we can stop at the first | |
256 | * unpurgable resource -- anyone added after | |
257 | * him will have a greater last_used value */ | |
7beaf243 | 258 | spin_unlock(&lockres->spinlock); |
6714d8e8 KH |
259 | break; |
260 | } | |
261 | ||
7beaf243 SE |
262 | /* Status of the lockres *might* change so double |
263 | * check. If the lockres is unused, holding the dlm | |
264 | * spinlock will prevent people from getting and more | |
265 | * refs on it. */ | |
266 | unused = __dlm_lockres_unused(lockres); | |
267 | if (!unused || | |
268 | (lockres->state & DLM_LOCK_RES_MIGRATING)) { | |
269 | mlog(0, "lockres %s:%.*s: is in use or " | |
270 | "being remastered, used %d, state %d\n", | |
271 | dlm->name, lockres->lockname.len, | |
272 | lockres->lockname.name, !unused, lockres->state); | |
273 | list_move_tail(&dlm->purge_list, &lockres->purge); | |
274 | spin_unlock(&lockres->spinlock); | |
275 | continue; | |
276 | } | |
277 | ||
78062cb2 | 278 | dlm_lockres_get(lockres); |
6714d8e8 | 279 | |
7beaf243 | 280 | dlm_purge_lockres(dlm, lockres); |
78062cb2 | 281 | |
3fca0894 | 282 | dlm_lockres_put(lockres); |
6714d8e8 KH |
283 | |
284 | /* Avoid adding any scheduling latencies */ | |
285 | cond_resched_lock(&dlm->spinlock); | |
286 | } | |
287 | ||
288 | spin_unlock(&dlm->spinlock); | |
289 | } | |
290 | ||
291 | static void dlm_shuffle_lists(struct dlm_ctxt *dlm, | |
292 | struct dlm_lock_resource *res) | |
293 | { | |
294 | struct dlm_lock *lock, *target; | |
295 | struct list_head *iter; | |
296 | struct list_head *head; | |
297 | int can_grant = 1; | |
298 | ||
299 | //mlog(0, "res->lockname.len=%d\n", res->lockname.len); | |
300 | //mlog(0, "res->lockname.name=%p\n", res->lockname.name); | |
301 | //mlog(0, "shuffle res %.*s\n", res->lockname.len, | |
302 | // res->lockname.name); | |
303 | ||
304 | /* because this function is called with the lockres | |
305 | * spinlock, and because we know that it is not migrating/ | |
306 | * recovering/in-progress, it is fine to reserve asts and | |
307 | * basts right before queueing them all throughout */ | |
d9ef7522 | 308 | assert_spin_locked(&dlm->ast_lock); |
6714d8e8 KH |
309 | assert_spin_locked(&res->spinlock); |
310 | BUG_ON((res->state & (DLM_LOCK_RES_MIGRATING| | |
311 | DLM_LOCK_RES_RECOVERING| | |
312 | DLM_LOCK_RES_IN_PROGRESS))); | |
313 | ||
314 | converting: | |
315 | if (list_empty(&res->converting)) | |
316 | goto blocked; | |
317 | mlog(0, "res %.*s has locks on a convert queue\n", res->lockname.len, | |
318 | res->lockname.name); | |
319 | ||
320 | target = list_entry(res->converting.next, struct dlm_lock, list); | |
321 | if (target->ml.convert_type == LKM_IVMODE) { | |
322 | mlog(ML_ERROR, "%.*s: converting a lock with no " | |
323 | "convert_type!\n", res->lockname.len, res->lockname.name); | |
324 | BUG(); | |
325 | } | |
326 | head = &res->granted; | |
327 | list_for_each(iter, head) { | |
328 | lock = list_entry(iter, struct dlm_lock, list); | |
329 | if (lock==target) | |
330 | continue; | |
331 | if (!dlm_lock_compatible(lock->ml.type, | |
332 | target->ml.convert_type)) { | |
333 | can_grant = 0; | |
334 | /* queue the BAST if not already */ | |
335 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
336 | __dlm_lockres_reserve_ast(res); | |
d9ef7522 | 337 | __dlm_queue_bast(dlm, lock); |
6714d8e8 KH |
338 | } |
339 | /* update the highest_blocked if needed */ | |
340 | if (lock->ml.highest_blocked < target->ml.convert_type) | |
341 | lock->ml.highest_blocked = | |
342 | target->ml.convert_type; | |
343 | } | |
344 | } | |
345 | head = &res->converting; | |
346 | list_for_each(iter, head) { | |
347 | lock = list_entry(iter, struct dlm_lock, list); | |
348 | if (lock==target) | |
349 | continue; | |
350 | if (!dlm_lock_compatible(lock->ml.type, | |
351 | target->ml.convert_type)) { | |
352 | can_grant = 0; | |
353 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
354 | __dlm_lockres_reserve_ast(res); | |
d9ef7522 | 355 | __dlm_queue_bast(dlm, lock); |
6714d8e8 KH |
356 | } |
357 | if (lock->ml.highest_blocked < target->ml.convert_type) | |
358 | lock->ml.highest_blocked = | |
359 | target->ml.convert_type; | |
360 | } | |
361 | } | |
362 | ||
363 | /* we can convert the lock */ | |
364 | if (can_grant) { | |
365 | spin_lock(&target->spinlock); | |
366 | BUG_ON(target->ml.highest_blocked != LKM_IVMODE); | |
367 | ||
368 | mlog(0, "calling ast for converting lock: %.*s, have: %d, " | |
369 | "granting: %d, node: %u\n", res->lockname.len, | |
370 | res->lockname.name, target->ml.type, | |
371 | target->ml.convert_type, target->ml.node); | |
372 | ||
373 | target->ml.type = target->ml.convert_type; | |
374 | target->ml.convert_type = LKM_IVMODE; | |
f116629d | 375 | list_move_tail(&target->list, &res->granted); |
6714d8e8 KH |
376 | |
377 | BUG_ON(!target->lksb); | |
378 | target->lksb->status = DLM_NORMAL; | |
379 | ||
380 | spin_unlock(&target->spinlock); | |
381 | ||
382 | __dlm_lockres_reserve_ast(res); | |
d9ef7522 | 383 | __dlm_queue_ast(dlm, target); |
6714d8e8 KH |
384 | /* go back and check for more */ |
385 | goto converting; | |
386 | } | |
387 | ||
388 | blocked: | |
389 | if (list_empty(&res->blocked)) | |
390 | goto leave; | |
391 | target = list_entry(res->blocked.next, struct dlm_lock, list); | |
392 | ||
393 | head = &res->granted; | |
394 | list_for_each(iter, head) { | |
395 | lock = list_entry(iter, struct dlm_lock, list); | |
396 | if (lock==target) | |
397 | continue; | |
398 | if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) { | |
399 | can_grant = 0; | |
400 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
401 | __dlm_lockres_reserve_ast(res); | |
d9ef7522 | 402 | __dlm_queue_bast(dlm, lock); |
6714d8e8 KH |
403 | } |
404 | if (lock->ml.highest_blocked < target->ml.type) | |
405 | lock->ml.highest_blocked = target->ml.type; | |
406 | } | |
407 | } | |
408 | ||
409 | head = &res->converting; | |
410 | list_for_each(iter, head) { | |
411 | lock = list_entry(iter, struct dlm_lock, list); | |
412 | if (lock==target) | |
413 | continue; | |
414 | if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) { | |
415 | can_grant = 0; | |
416 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
417 | __dlm_lockres_reserve_ast(res); | |
d9ef7522 | 418 | __dlm_queue_bast(dlm, lock); |
6714d8e8 KH |
419 | } |
420 | if (lock->ml.highest_blocked < target->ml.type) | |
421 | lock->ml.highest_blocked = target->ml.type; | |
422 | } | |
423 | } | |
424 | ||
425 | /* we can grant the blocked lock (only | |
426 | * possible if converting list empty) */ | |
427 | if (can_grant) { | |
428 | spin_lock(&target->spinlock); | |
429 | BUG_ON(target->ml.highest_blocked != LKM_IVMODE); | |
430 | ||
431 | mlog(0, "calling ast for blocked lock: %.*s, granting: %d, " | |
432 | "node: %u\n", res->lockname.len, res->lockname.name, | |
433 | target->ml.type, target->ml.node); | |
434 | ||
435 | // target->ml.type is already correct | |
f116629d | 436 | list_move_tail(&target->list, &res->granted); |
6714d8e8 KH |
437 | |
438 | BUG_ON(!target->lksb); | |
439 | target->lksb->status = DLM_NORMAL; | |
440 | ||
441 | spin_unlock(&target->spinlock); | |
442 | ||
443 | __dlm_lockres_reserve_ast(res); | |
d9ef7522 | 444 | __dlm_queue_ast(dlm, target); |
6714d8e8 KH |
445 | /* go back and check for more */ |
446 | goto converting; | |
447 | } | |
448 | ||
449 | leave: | |
450 | return; | |
451 | } | |
452 | ||
453 | /* must have NO locks when calling this with res !=NULL * */ | |
454 | void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) | |
455 | { | |
456 | mlog_entry("dlm=%p, res=%p\n", dlm, res); | |
457 | if (res) { | |
458 | spin_lock(&dlm->spinlock); | |
459 | spin_lock(&res->spinlock); | |
460 | __dlm_dirty_lockres(dlm, res); | |
461 | spin_unlock(&res->spinlock); | |
462 | spin_unlock(&dlm->spinlock); | |
463 | } | |
464 | wake_up(&dlm->dlm_thread_wq); | |
465 | } | |
466 | ||
467 | void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) | |
468 | { | |
469 | mlog_entry("dlm=%p, res=%p\n", dlm, res); | |
470 | ||
471 | assert_spin_locked(&dlm->spinlock); | |
472 | assert_spin_locked(&res->spinlock); | |
473 | ||
474 | /* don't shuffle secondary queues */ | |
ddc09c8d KH |
475 | if ((res->owner == dlm->node_num)) { |
476 | if (res->state & (DLM_LOCK_RES_MIGRATING | | |
477 | DLM_LOCK_RES_BLOCK_DIRTY)) | |
478 | return; | |
479 | ||
480 | if (list_empty(&res->dirty)) { | |
481 | /* ref for dirty_list */ | |
482 | dlm_lockres_get(res); | |
483 | list_add_tail(&res->dirty, &dlm->dirty_list); | |
484 | res->state |= DLM_LOCK_RES_DIRTY; | |
485 | } | |
6714d8e8 KH |
486 | } |
487 | } | |
488 | ||
489 | ||
490 | /* Launch the NM thread for the mounted volume */ | |
491 | int dlm_launch_thread(struct dlm_ctxt *dlm) | |
492 | { | |
493 | mlog(0, "starting dlm thread...\n"); | |
494 | ||
495 | dlm->dlm_thread_task = kthread_run(dlm_thread, dlm, "dlm_thread"); | |
496 | if (IS_ERR(dlm->dlm_thread_task)) { | |
497 | mlog_errno(PTR_ERR(dlm->dlm_thread_task)); | |
498 | dlm->dlm_thread_task = NULL; | |
499 | return -EINVAL; | |
500 | } | |
501 | ||
502 | return 0; | |
503 | } | |
504 | ||
505 | void dlm_complete_thread(struct dlm_ctxt *dlm) | |
506 | { | |
507 | if (dlm->dlm_thread_task) { | |
508 | mlog(ML_KTHREAD, "waiting for dlm thread to exit\n"); | |
509 | kthread_stop(dlm->dlm_thread_task); | |
510 | dlm->dlm_thread_task = NULL; | |
511 | } | |
512 | } | |
513 | ||
514 | static int dlm_dirty_list_empty(struct dlm_ctxt *dlm) | |
515 | { | |
516 | int empty; | |
517 | ||
518 | spin_lock(&dlm->spinlock); | |
519 | empty = list_empty(&dlm->dirty_list); | |
520 | spin_unlock(&dlm->spinlock); | |
521 | ||
522 | return empty; | |
523 | } | |
524 | ||
525 | static void dlm_flush_asts(struct dlm_ctxt *dlm) | |
526 | { | |
527 | int ret; | |
528 | struct dlm_lock *lock; | |
529 | struct dlm_lock_resource *res; | |
530 | u8 hi; | |
531 | ||
532 | spin_lock(&dlm->ast_lock); | |
533 | while (!list_empty(&dlm->pending_asts)) { | |
534 | lock = list_entry(dlm->pending_asts.next, | |
535 | struct dlm_lock, ast_list); | |
536 | /* get an extra ref on lock */ | |
537 | dlm_lock_get(lock); | |
538 | res = lock->lockres; | |
539 | mlog(0, "delivering an ast for this lockres\n"); | |
540 | ||
541 | BUG_ON(!lock->ast_pending); | |
542 | ||
543 | /* remove from list (including ref) */ | |
544 | list_del_init(&lock->ast_list); | |
545 | dlm_lock_put(lock); | |
546 | spin_unlock(&dlm->ast_lock); | |
547 | ||
548 | if (lock->ml.node != dlm->node_num) { | |
549 | ret = dlm_do_remote_ast(dlm, res, lock); | |
550 | if (ret < 0) | |
551 | mlog_errno(ret); | |
552 | } else | |
553 | dlm_do_local_ast(dlm, res, lock); | |
554 | ||
555 | spin_lock(&dlm->ast_lock); | |
556 | ||
557 | /* possible that another ast was queued while | |
558 | * we were delivering the last one */ | |
559 | if (!list_empty(&lock->ast_list)) { | |
560 | mlog(0, "aha another ast got queued while " | |
561 | "we were finishing the last one. will " | |
562 | "keep the ast_pending flag set.\n"); | |
563 | } else | |
564 | lock->ast_pending = 0; | |
565 | ||
566 | /* drop the extra ref. | |
567 | * this may drop it completely. */ | |
568 | dlm_lock_put(lock); | |
569 | dlm_lockres_release_ast(dlm, res); | |
570 | } | |
571 | ||
572 | while (!list_empty(&dlm->pending_basts)) { | |
573 | lock = list_entry(dlm->pending_basts.next, | |
574 | struct dlm_lock, bast_list); | |
575 | /* get an extra ref on lock */ | |
576 | dlm_lock_get(lock); | |
577 | res = lock->lockres; | |
578 | ||
579 | BUG_ON(!lock->bast_pending); | |
580 | ||
581 | /* get the highest blocked lock, and reset */ | |
582 | spin_lock(&lock->spinlock); | |
583 | BUG_ON(lock->ml.highest_blocked <= LKM_IVMODE); | |
584 | hi = lock->ml.highest_blocked; | |
585 | lock->ml.highest_blocked = LKM_IVMODE; | |
586 | spin_unlock(&lock->spinlock); | |
587 | ||
588 | /* remove from list (including ref) */ | |
589 | list_del_init(&lock->bast_list); | |
590 | dlm_lock_put(lock); | |
591 | spin_unlock(&dlm->ast_lock); | |
592 | ||
593 | mlog(0, "delivering a bast for this lockres " | |
594 | "(blocked = %d\n", hi); | |
595 | ||
596 | if (lock->ml.node != dlm->node_num) { | |
597 | ret = dlm_send_proxy_bast(dlm, res, lock, hi); | |
598 | if (ret < 0) | |
599 | mlog_errno(ret); | |
600 | } else | |
601 | dlm_do_local_bast(dlm, res, lock, hi); | |
602 | ||
603 | spin_lock(&dlm->ast_lock); | |
604 | ||
605 | /* possible that another bast was queued while | |
606 | * we were delivering the last one */ | |
607 | if (!list_empty(&lock->bast_list)) { | |
608 | mlog(0, "aha another bast got queued while " | |
609 | "we were finishing the last one. will " | |
610 | "keep the bast_pending flag set.\n"); | |
611 | } else | |
612 | lock->bast_pending = 0; | |
613 | ||
614 | /* drop the extra ref. | |
615 | * this may drop it completely. */ | |
616 | dlm_lock_put(lock); | |
617 | dlm_lockres_release_ast(dlm, res); | |
618 | } | |
619 | wake_up(&dlm->ast_wq); | |
620 | spin_unlock(&dlm->ast_lock); | |
621 | } | |
622 | ||
623 | ||
624 | #define DLM_THREAD_TIMEOUT_MS (4 * 1000) | |
625 | #define DLM_THREAD_MAX_DIRTY 100 | |
626 | #define DLM_THREAD_MAX_ASTS 10 | |
627 | ||
628 | static int dlm_thread(void *data) | |
629 | { | |
630 | struct dlm_lock_resource *res; | |
631 | struct dlm_ctxt *dlm = data; | |
632 | unsigned long timeout = msecs_to_jiffies(DLM_THREAD_TIMEOUT_MS); | |
633 | ||
634 | mlog(0, "dlm thread running for %s...\n", dlm->name); | |
635 | ||
636 | while (!kthread_should_stop()) { | |
637 | int n = DLM_THREAD_MAX_DIRTY; | |
638 | ||
639 | /* dlm_shutting_down is very point-in-time, but that | |
640 | * doesn't matter as we'll just loop back around if we | |
641 | * get false on the leading edge of a state | |
642 | * transition. */ | |
643 | dlm_run_purge_list(dlm, dlm_shutting_down(dlm)); | |
644 | ||
645 | /* We really don't want to hold dlm->spinlock while | |
646 | * calling dlm_shuffle_lists on each lockres that | |
647 | * needs to have its queues adjusted and AST/BASTs | |
648 | * run. So let's pull each entry off the dirty_list | |
649 | * and drop dlm->spinlock ASAP. Once off the list, | |
650 | * res->spinlock needs to be taken again to protect | |
651 | * the queues while calling dlm_shuffle_lists. */ | |
652 | spin_lock(&dlm->spinlock); | |
653 | while (!list_empty(&dlm->dirty_list)) { | |
654 | int delay = 0; | |
655 | res = list_entry(dlm->dirty_list.next, | |
656 | struct dlm_lock_resource, dirty); | |
657 | ||
658 | /* peel a lockres off, remove it from the list, | |
659 | * unset the dirty flag and drop the dlm lock */ | |
660 | BUG_ON(!res); | |
661 | dlm_lockres_get(res); | |
662 | ||
663 | spin_lock(&res->spinlock); | |
ddc09c8d | 664 | /* We clear the DLM_LOCK_RES_DIRTY state once we shuffle lists below */ |
6714d8e8 KH |
665 | list_del_init(&res->dirty); |
666 | spin_unlock(&res->spinlock); | |
667 | spin_unlock(&dlm->spinlock); | |
6ff06a93 KH |
668 | /* Drop dirty_list ref */ |
669 | dlm_lockres_put(res); | |
6714d8e8 KH |
670 | |
671 | /* lockres can be re-dirtied/re-added to the | |
672 | * dirty_list in this gap, but that is ok */ | |
673 | ||
d9ef7522 | 674 | spin_lock(&dlm->ast_lock); |
6714d8e8 KH |
675 | spin_lock(&res->spinlock); |
676 | if (res->owner != dlm->node_num) { | |
677 | __dlm_print_one_lock_resource(res); | |
678 | mlog(ML_ERROR, "inprog:%s, mig:%s, reco:%s, dirty:%s\n", | |
679 | res->state & DLM_LOCK_RES_IN_PROGRESS ? "yes" : "no", | |
680 | res->state & DLM_LOCK_RES_MIGRATING ? "yes" : "no", | |
681 | res->state & DLM_LOCK_RES_RECOVERING ? "yes" : "no", | |
682 | res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no"); | |
683 | } | |
684 | BUG_ON(res->owner != dlm->node_num); | |
685 | ||
686 | /* it is now ok to move lockreses in these states | |
687 | * to the dirty list, assuming that they will only be | |
688 | * dirty for a short while. */ | |
ddc09c8d | 689 | BUG_ON(res->state & DLM_LOCK_RES_MIGRATING); |
6714d8e8 | 690 | if (res->state & (DLM_LOCK_RES_IN_PROGRESS | |
6714d8e8 KH |
691 | DLM_LOCK_RES_RECOVERING)) { |
692 | /* move it to the tail and keep going */ | |
ddc09c8d | 693 | res->state &= ~DLM_LOCK_RES_DIRTY; |
6714d8e8 | 694 | spin_unlock(&res->spinlock); |
d9ef7522 | 695 | spin_unlock(&dlm->ast_lock); |
6714d8e8 KH |
696 | mlog(0, "delaying list shuffling for in-" |
697 | "progress lockres %.*s, state=%d\n", | |
698 | res->lockname.len, res->lockname.name, | |
699 | res->state); | |
700 | delay = 1; | |
701 | goto in_progress; | |
702 | } | |
703 | ||
704 | /* at this point the lockres is not migrating/ | |
705 | * recovering/in-progress. we have the lockres | |
706 | * spinlock and do NOT have the dlm lock. | |
707 | * safe to reserve/queue asts and run the lists. */ | |
708 | ||
8d79d088 KH |
709 | mlog(0, "calling dlm_shuffle_lists with dlm=%s, " |
710 | "res=%.*s\n", dlm->name, | |
711 | res->lockname.len, res->lockname.name); | |
6714d8e8 KH |
712 | |
713 | /* called while holding lockres lock */ | |
714 | dlm_shuffle_lists(dlm, res); | |
ddc09c8d | 715 | res->state &= ~DLM_LOCK_RES_DIRTY; |
6714d8e8 | 716 | spin_unlock(&res->spinlock); |
d9ef7522 | 717 | spin_unlock(&dlm->ast_lock); |
6714d8e8 KH |
718 | |
719 | dlm_lockres_calc_usage(dlm, res); | |
720 | ||
721 | in_progress: | |
722 | ||
723 | spin_lock(&dlm->spinlock); | |
724 | /* if the lock was in-progress, stick | |
725 | * it on the back of the list */ | |
726 | if (delay) { | |
727 | spin_lock(&res->spinlock); | |
ddc09c8d | 728 | __dlm_dirty_lockres(dlm, res); |
6714d8e8 KH |
729 | spin_unlock(&res->spinlock); |
730 | } | |
731 | dlm_lockres_put(res); | |
732 | ||
733 | /* unlikely, but we may need to give time to | |
734 | * other tasks */ | |
735 | if (!--n) { | |
736 | mlog(0, "throttling dlm_thread\n"); | |
737 | break; | |
738 | } | |
739 | } | |
740 | ||
741 | spin_unlock(&dlm->spinlock); | |
742 | dlm_flush_asts(dlm); | |
743 | ||
744 | /* yield and continue right away if there is more work to do */ | |
745 | if (!n) { | |
f85cd47a | 746 | cond_resched(); |
6714d8e8 KH |
747 | continue; |
748 | } | |
749 | ||
750 | wait_event_interruptible_timeout(dlm->dlm_thread_wq, | |
751 | !dlm_dirty_list_empty(dlm) || | |
752 | kthread_should_stop(), | |
753 | timeout); | |
754 | } | |
755 | ||
756 | mlog(0, "quitting DLM thread\n"); | |
757 | return 0; | |
758 | } |