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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 | { | |
95 | if (!__dlm_lockres_has_locks(res) && | |
ddc09c8d | 96 | (list_empty(&res->dirty) && !(res->state & DLM_LOCK_RES_DIRTY))) { |
ba2bf218 KH |
97 | /* try not to scan the bitmap unless the first two |
98 | * conditions are already true */ | |
99 | int bit = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); | |
100 | if (bit >= O2NM_MAX_NODES) { | |
101 | /* since the bit for dlm->node_num is not | |
102 | * set, inflight_locks better be zero */ | |
103 | BUG_ON(res->inflight_locks != 0); | |
104 | return 1; | |
105 | } | |
106 | } | |
6714d8e8 KH |
107 | return 0; |
108 | } | |
109 | ||
110 | ||
111 | /* Call whenever you may have added or deleted something from one of | |
112 | * the lockres queue's. This will figure out whether it belongs on the | |
113 | * unused list or not and does the appropriate thing. */ | |
114 | void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm, | |
115 | struct dlm_lock_resource *res) | |
116 | { | |
117 | mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); | |
118 | ||
119 | assert_spin_locked(&dlm->spinlock); | |
120 | assert_spin_locked(&res->spinlock); | |
121 | ||
122 | if (__dlm_lockres_unused(res)){ | |
123 | if (list_empty(&res->purge)) { | |
ba2bf218 KH |
124 | mlog(0, "putting lockres %.*s:%p onto purge list\n", |
125 | res->lockname.len, res->lockname.name, res); | |
6714d8e8 KH |
126 | |
127 | res->last_used = jiffies; | |
ba2bf218 | 128 | dlm_lockres_get(res); |
6714d8e8 KH |
129 | list_add_tail(&res->purge, &dlm->purge_list); |
130 | dlm->purge_count++; | |
131 | } | |
132 | } else if (!list_empty(&res->purge)) { | |
ba2bf218 KH |
133 | mlog(0, "removing lockres %.*s:%p from purge list, owner=%u\n", |
134 | res->lockname.len, res->lockname.name, res, res->owner); | |
6714d8e8 KH |
135 | |
136 | list_del_init(&res->purge); | |
ba2bf218 | 137 | dlm_lockres_put(res); |
6714d8e8 KH |
138 | dlm->purge_count--; |
139 | } | |
140 | } | |
141 | ||
142 | void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, | |
143 | struct dlm_lock_resource *res) | |
144 | { | |
145 | mlog_entry("%.*s\n", res->lockname.len, res->lockname.name); | |
146 | spin_lock(&dlm->spinlock); | |
147 | spin_lock(&res->spinlock); | |
148 | ||
149 | __dlm_lockres_calc_usage(dlm, res); | |
150 | ||
151 | spin_unlock(&res->spinlock); | |
152 | spin_unlock(&dlm->spinlock); | |
153 | } | |
154 | ||
faf0ec9f AB |
155 | static int dlm_purge_lockres(struct dlm_ctxt *dlm, |
156 | struct dlm_lock_resource *res) | |
6714d8e8 KH |
157 | { |
158 | int master; | |
ba2bf218 | 159 | int ret = 0; |
6714d8e8 | 160 | |
ba2bf218 KH |
161 | spin_lock(&res->spinlock); |
162 | if (!__dlm_lockres_unused(res)) { | |
ba2bf218 KH |
163 | mlog(0, "%s:%.*s: tried to purge but not unused\n", |
164 | dlm->name, res->lockname.len, res->lockname.name); | |
516b7e52 SM |
165 | __dlm_print_one_lock_resource(res); |
166 | spin_unlock(&res->spinlock); | |
167 | BUG(); | |
168 | } | |
169 | ||
170 | if (res->state & DLM_LOCK_RES_MIGRATING) { | |
171 | mlog(0, "%s:%.*s: Delay dropref as this lockres is " | |
172 | "being remastered\n", dlm->name, res->lockname.len, | |
173 | res->lockname.name); | |
174 | /* Re-add the lockres to the end of the purge list */ | |
175 | if (!list_empty(&res->purge)) { | |
176 | list_del_init(&res->purge); | |
177 | list_add_tail(&res->purge, &dlm->purge_list); | |
178 | } | |
179 | spin_unlock(&res->spinlock); | |
180 | return 0; | |
ba2bf218 | 181 | } |
516b7e52 | 182 | |
ba2bf218 | 183 | master = (res->owner == dlm->node_num); |
516b7e52 | 184 | |
6714d8e8 | 185 | if (!master) |
ba2bf218 KH |
186 | res->state |= DLM_LOCK_RES_DROPPING_REF; |
187 | spin_unlock(&res->spinlock); | |
6714d8e8 | 188 | |
ba2bf218 KH |
189 | mlog(0, "purging lockres %.*s, master = %d\n", res->lockname.len, |
190 | res->lockname.name, master); | |
191 | ||
192 | if (!master) { | |
c824c3c7 SM |
193 | /* drop spinlock... retake below */ |
194 | spin_unlock(&dlm->spinlock); | |
195 | ||
3b8118cf KH |
196 | spin_lock(&res->spinlock); |
197 | /* This ensures that clear refmap is sent after the set */ | |
7dc102b7 | 198 | __dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG); |
3b8118cf | 199 | spin_unlock(&res->spinlock); |
c824c3c7 | 200 | |
ba2bf218 KH |
201 | /* clear our bit from the master's refmap, ignore errors */ |
202 | ret = dlm_drop_lockres_ref(dlm, res); | |
203 | if (ret < 0) { | |
204 | mlog_errno(ret); | |
205 | if (!dlm_is_host_down(ret)) | |
206 | BUG(); | |
207 | } | |
208 | mlog(0, "%s:%.*s: dlm_deref_lockres returned %d\n", | |
209 | dlm->name, res->lockname.len, res->lockname.name, ret); | |
210 | spin_lock(&dlm->spinlock); | |
6714d8e8 KH |
211 | } |
212 | ||
83e32d90 | 213 | spin_lock(&res->spinlock); |
ba2bf218 KH |
214 | if (!list_empty(&res->purge)) { |
215 | mlog(0, "removing lockres %.*s:%p from purgelist, " | |
216 | "master = %d\n", res->lockname.len, res->lockname.name, | |
217 | res, master); | |
218 | list_del_init(&res->purge); | |
83e32d90 | 219 | spin_unlock(&res->spinlock); |
ba2bf218 | 220 | dlm_lockres_put(res); |
6714d8e8 | 221 | dlm->purge_count--; |
83e32d90 WW |
222 | } else |
223 | spin_unlock(&res->spinlock); | |
224 | ||
ba2bf218 | 225 | __dlm_unhash_lockres(res); |
6714d8e8 | 226 | |
ba2bf218 KH |
227 | /* lockres is not in the hash now. drop the flag and wake up |
228 | * any processes waiting in dlm_get_lock_resource. */ | |
229 | if (!master) { | |
230 | spin_lock(&res->spinlock); | |
231 | res->state &= ~DLM_LOCK_RES_DROPPING_REF; | |
232 | spin_unlock(&res->spinlock); | |
233 | wake_up(&res->wq); | |
8b219809 | 234 | } |
ba2bf218 | 235 | return 0; |
8b219809 KH |
236 | } |
237 | ||
6714d8e8 KH |
238 | static void dlm_run_purge_list(struct dlm_ctxt *dlm, |
239 | int purge_now) | |
240 | { | |
241 | unsigned int run_max, unused; | |
242 | unsigned long purge_jiffies; | |
243 | struct dlm_lock_resource *lockres; | |
244 | ||
245 | spin_lock(&dlm->spinlock); | |
246 | run_max = dlm->purge_count; | |
247 | ||
248 | while(run_max && !list_empty(&dlm->purge_list)) { | |
249 | run_max--; | |
250 | ||
251 | lockres = list_entry(dlm->purge_list.next, | |
252 | struct dlm_lock_resource, purge); | |
253 | ||
254 | /* Status of the lockres *might* change so double | |
255 | * check. If the lockres is unused, holding the dlm | |
256 | * spinlock will prevent people from getting and more | |
257 | * refs on it -- there's no need to keep the lockres | |
258 | * spinlock. */ | |
259 | spin_lock(&lockres->spinlock); | |
260 | unused = __dlm_lockres_unused(lockres); | |
261 | spin_unlock(&lockres->spinlock); | |
262 | ||
263 | if (!unused) | |
264 | continue; | |
265 | ||
266 | purge_jiffies = lockres->last_used + | |
267 | msecs_to_jiffies(DLM_PURGE_INTERVAL_MS); | |
268 | ||
269 | /* Make sure that we want to be processing this guy at | |
270 | * this time. */ | |
271 | if (!purge_now && time_after(purge_jiffies, jiffies)) { | |
272 | /* Since resources are added to the purge list | |
273 | * in tail order, we can stop at the first | |
274 | * unpurgable resource -- anyone added after | |
275 | * him will have a greater last_used value */ | |
276 | break; | |
277 | } | |
278 | ||
78062cb2 | 279 | dlm_lockres_get(lockres); |
6714d8e8 KH |
280 | |
281 | /* This may drop and reacquire the dlm spinlock if it | |
282 | * has to do migration. */ | |
ba2bf218 KH |
283 | if (dlm_purge_lockres(dlm, lockres)) |
284 | BUG(); | |
78062cb2 | 285 | |
3fca0894 | 286 | dlm_lockres_put(lockres); |
6714d8e8 KH |
287 | |
288 | /* Avoid adding any scheduling latencies */ | |
289 | cond_resched_lock(&dlm->spinlock); | |
290 | } | |
291 | ||
292 | spin_unlock(&dlm->spinlock); | |
293 | } | |
294 | ||
295 | static void dlm_shuffle_lists(struct dlm_ctxt *dlm, | |
296 | struct dlm_lock_resource *res) | |
297 | { | |
298 | struct dlm_lock *lock, *target; | |
299 | struct list_head *iter; | |
300 | struct list_head *head; | |
301 | int can_grant = 1; | |
302 | ||
303 | //mlog(0, "res->lockname.len=%d\n", res->lockname.len); | |
304 | //mlog(0, "res->lockname.name=%p\n", res->lockname.name); | |
305 | //mlog(0, "shuffle res %.*s\n", res->lockname.len, | |
306 | // res->lockname.name); | |
307 | ||
308 | /* because this function is called with the lockres | |
309 | * spinlock, and because we know that it is not migrating/ | |
310 | * recovering/in-progress, it is fine to reserve asts and | |
311 | * basts right before queueing them all throughout */ | |
312 | assert_spin_locked(&res->spinlock); | |
313 | BUG_ON((res->state & (DLM_LOCK_RES_MIGRATING| | |
314 | DLM_LOCK_RES_RECOVERING| | |
315 | DLM_LOCK_RES_IN_PROGRESS))); | |
316 | ||
317 | converting: | |
318 | if (list_empty(&res->converting)) | |
319 | goto blocked; | |
320 | mlog(0, "res %.*s has locks on a convert queue\n", res->lockname.len, | |
321 | res->lockname.name); | |
322 | ||
323 | target = list_entry(res->converting.next, struct dlm_lock, list); | |
324 | if (target->ml.convert_type == LKM_IVMODE) { | |
325 | mlog(ML_ERROR, "%.*s: converting a lock with no " | |
326 | "convert_type!\n", res->lockname.len, res->lockname.name); | |
327 | BUG(); | |
328 | } | |
329 | head = &res->granted; | |
330 | list_for_each(iter, head) { | |
331 | lock = list_entry(iter, struct dlm_lock, list); | |
332 | if (lock==target) | |
333 | continue; | |
334 | if (!dlm_lock_compatible(lock->ml.type, | |
335 | target->ml.convert_type)) { | |
336 | can_grant = 0; | |
337 | /* queue the BAST if not already */ | |
338 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
339 | __dlm_lockres_reserve_ast(res); | |
340 | dlm_queue_bast(dlm, lock); | |
341 | } | |
342 | /* update the highest_blocked if needed */ | |
343 | if (lock->ml.highest_blocked < target->ml.convert_type) | |
344 | lock->ml.highest_blocked = | |
345 | target->ml.convert_type; | |
346 | } | |
347 | } | |
348 | head = &res->converting; | |
349 | list_for_each(iter, head) { | |
350 | lock = list_entry(iter, struct dlm_lock, list); | |
351 | if (lock==target) | |
352 | continue; | |
353 | if (!dlm_lock_compatible(lock->ml.type, | |
354 | target->ml.convert_type)) { | |
355 | can_grant = 0; | |
356 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
357 | __dlm_lockres_reserve_ast(res); | |
358 | dlm_queue_bast(dlm, lock); | |
359 | } | |
360 | if (lock->ml.highest_blocked < target->ml.convert_type) | |
361 | lock->ml.highest_blocked = | |
362 | target->ml.convert_type; | |
363 | } | |
364 | } | |
365 | ||
366 | /* we can convert the lock */ | |
367 | if (can_grant) { | |
368 | spin_lock(&target->spinlock); | |
369 | BUG_ON(target->ml.highest_blocked != LKM_IVMODE); | |
370 | ||
371 | mlog(0, "calling ast for converting lock: %.*s, have: %d, " | |
372 | "granting: %d, node: %u\n", res->lockname.len, | |
373 | res->lockname.name, target->ml.type, | |
374 | target->ml.convert_type, target->ml.node); | |
375 | ||
376 | target->ml.type = target->ml.convert_type; | |
377 | target->ml.convert_type = LKM_IVMODE; | |
f116629d | 378 | list_move_tail(&target->list, &res->granted); |
6714d8e8 KH |
379 | |
380 | BUG_ON(!target->lksb); | |
381 | target->lksb->status = DLM_NORMAL; | |
382 | ||
383 | spin_unlock(&target->spinlock); | |
384 | ||
385 | __dlm_lockres_reserve_ast(res); | |
386 | dlm_queue_ast(dlm, target); | |
387 | /* go back and check for more */ | |
388 | goto converting; | |
389 | } | |
390 | ||
391 | blocked: | |
392 | if (list_empty(&res->blocked)) | |
393 | goto leave; | |
394 | target = list_entry(res->blocked.next, struct dlm_lock, list); | |
395 | ||
396 | head = &res->granted; | |
397 | list_for_each(iter, head) { | |
398 | lock = list_entry(iter, struct dlm_lock, list); | |
399 | if (lock==target) | |
400 | continue; | |
401 | if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) { | |
402 | can_grant = 0; | |
403 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
404 | __dlm_lockres_reserve_ast(res); | |
405 | dlm_queue_bast(dlm, lock); | |
406 | } | |
407 | if (lock->ml.highest_blocked < target->ml.type) | |
408 | lock->ml.highest_blocked = target->ml.type; | |
409 | } | |
410 | } | |
411 | ||
412 | head = &res->converting; | |
413 | list_for_each(iter, head) { | |
414 | lock = list_entry(iter, struct dlm_lock, list); | |
415 | if (lock==target) | |
416 | continue; | |
417 | if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) { | |
418 | can_grant = 0; | |
419 | if (lock->ml.highest_blocked == LKM_IVMODE) { | |
420 | __dlm_lockres_reserve_ast(res); | |
421 | dlm_queue_bast(dlm, lock); | |
422 | } | |
423 | if (lock->ml.highest_blocked < target->ml.type) | |
424 | lock->ml.highest_blocked = target->ml.type; | |
425 | } | |
426 | } | |
427 | ||
428 | /* we can grant the blocked lock (only | |
429 | * possible if converting list empty) */ | |
430 | if (can_grant) { | |
431 | spin_lock(&target->spinlock); | |
432 | BUG_ON(target->ml.highest_blocked != LKM_IVMODE); | |
433 | ||
434 | mlog(0, "calling ast for blocked lock: %.*s, granting: %d, " | |
435 | "node: %u\n", res->lockname.len, res->lockname.name, | |
436 | target->ml.type, target->ml.node); | |
437 | ||
438 | // target->ml.type is already correct | |
f116629d | 439 | list_move_tail(&target->list, &res->granted); |
6714d8e8 KH |
440 | |
441 | BUG_ON(!target->lksb); | |
442 | target->lksb->status = DLM_NORMAL; | |
443 | ||
444 | spin_unlock(&target->spinlock); | |
445 | ||
446 | __dlm_lockres_reserve_ast(res); | |
447 | dlm_queue_ast(dlm, target); | |
448 | /* go back and check for more */ | |
449 | goto converting; | |
450 | } | |
451 | ||
452 | leave: | |
453 | return; | |
454 | } | |
455 | ||
456 | /* must have NO locks when calling this with res !=NULL * */ | |
457 | void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) | |
458 | { | |
459 | mlog_entry("dlm=%p, res=%p\n", dlm, res); | |
460 | if (res) { | |
461 | spin_lock(&dlm->spinlock); | |
462 | spin_lock(&res->spinlock); | |
463 | __dlm_dirty_lockres(dlm, res); | |
464 | spin_unlock(&res->spinlock); | |
465 | spin_unlock(&dlm->spinlock); | |
466 | } | |
467 | wake_up(&dlm->dlm_thread_wq); | |
468 | } | |
469 | ||
470 | void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) | |
471 | { | |
472 | mlog_entry("dlm=%p, res=%p\n", dlm, res); | |
473 | ||
474 | assert_spin_locked(&dlm->spinlock); | |
475 | assert_spin_locked(&res->spinlock); | |
476 | ||
477 | /* don't shuffle secondary queues */ | |
ddc09c8d KH |
478 | if ((res->owner == dlm->node_num)) { |
479 | if (res->state & (DLM_LOCK_RES_MIGRATING | | |
480 | DLM_LOCK_RES_BLOCK_DIRTY)) | |
481 | return; | |
482 | ||
483 | if (list_empty(&res->dirty)) { | |
484 | /* ref for dirty_list */ | |
485 | dlm_lockres_get(res); | |
486 | list_add_tail(&res->dirty, &dlm->dirty_list); | |
487 | res->state |= DLM_LOCK_RES_DIRTY; | |
488 | } | |
6714d8e8 KH |
489 | } |
490 | } | |
491 | ||
492 | ||
493 | /* Launch the NM thread for the mounted volume */ | |
494 | int dlm_launch_thread(struct dlm_ctxt *dlm) | |
495 | { | |
496 | mlog(0, "starting dlm thread...\n"); | |
497 | ||
498 | dlm->dlm_thread_task = kthread_run(dlm_thread, dlm, "dlm_thread"); | |
499 | if (IS_ERR(dlm->dlm_thread_task)) { | |
500 | mlog_errno(PTR_ERR(dlm->dlm_thread_task)); | |
501 | dlm->dlm_thread_task = NULL; | |
502 | return -EINVAL; | |
503 | } | |
504 | ||
505 | return 0; | |
506 | } | |
507 | ||
508 | void dlm_complete_thread(struct dlm_ctxt *dlm) | |
509 | { | |
510 | if (dlm->dlm_thread_task) { | |
511 | mlog(ML_KTHREAD, "waiting for dlm thread to exit\n"); | |
512 | kthread_stop(dlm->dlm_thread_task); | |
513 | dlm->dlm_thread_task = NULL; | |
514 | } | |
515 | } | |
516 | ||
517 | static int dlm_dirty_list_empty(struct dlm_ctxt *dlm) | |
518 | { | |
519 | int empty; | |
520 | ||
521 | spin_lock(&dlm->spinlock); | |
522 | empty = list_empty(&dlm->dirty_list); | |
523 | spin_unlock(&dlm->spinlock); | |
524 | ||
525 | return empty; | |
526 | } | |
527 | ||
528 | static void dlm_flush_asts(struct dlm_ctxt *dlm) | |
529 | { | |
530 | int ret; | |
531 | struct dlm_lock *lock; | |
532 | struct dlm_lock_resource *res; | |
533 | u8 hi; | |
534 | ||
535 | spin_lock(&dlm->ast_lock); | |
536 | while (!list_empty(&dlm->pending_asts)) { | |
537 | lock = list_entry(dlm->pending_asts.next, | |
538 | struct dlm_lock, ast_list); | |
539 | /* get an extra ref on lock */ | |
540 | dlm_lock_get(lock); | |
541 | res = lock->lockres; | |
542 | mlog(0, "delivering an ast for this lockres\n"); | |
543 | ||
544 | BUG_ON(!lock->ast_pending); | |
545 | ||
546 | /* remove from list (including ref) */ | |
547 | list_del_init(&lock->ast_list); | |
548 | dlm_lock_put(lock); | |
549 | spin_unlock(&dlm->ast_lock); | |
550 | ||
551 | if (lock->ml.node != dlm->node_num) { | |
552 | ret = dlm_do_remote_ast(dlm, res, lock); | |
553 | if (ret < 0) | |
554 | mlog_errno(ret); | |
555 | } else | |
556 | dlm_do_local_ast(dlm, res, lock); | |
557 | ||
558 | spin_lock(&dlm->ast_lock); | |
559 | ||
560 | /* possible that another ast was queued while | |
561 | * we were delivering the last one */ | |
562 | if (!list_empty(&lock->ast_list)) { | |
563 | mlog(0, "aha another ast got queued while " | |
564 | "we were finishing the last one. will " | |
565 | "keep the ast_pending flag set.\n"); | |
566 | } else | |
567 | lock->ast_pending = 0; | |
568 | ||
569 | /* drop the extra ref. | |
570 | * this may drop it completely. */ | |
571 | dlm_lock_put(lock); | |
572 | dlm_lockres_release_ast(dlm, res); | |
573 | } | |
574 | ||
575 | while (!list_empty(&dlm->pending_basts)) { | |
576 | lock = list_entry(dlm->pending_basts.next, | |
577 | struct dlm_lock, bast_list); | |
578 | /* get an extra ref on lock */ | |
579 | dlm_lock_get(lock); | |
580 | res = lock->lockres; | |
581 | ||
582 | BUG_ON(!lock->bast_pending); | |
583 | ||
584 | /* get the highest blocked lock, and reset */ | |
585 | spin_lock(&lock->spinlock); | |
586 | BUG_ON(lock->ml.highest_blocked <= LKM_IVMODE); | |
587 | hi = lock->ml.highest_blocked; | |
588 | lock->ml.highest_blocked = LKM_IVMODE; | |
589 | spin_unlock(&lock->spinlock); | |
590 | ||
591 | /* remove from list (including ref) */ | |
592 | list_del_init(&lock->bast_list); | |
593 | dlm_lock_put(lock); | |
594 | spin_unlock(&dlm->ast_lock); | |
595 | ||
596 | mlog(0, "delivering a bast for this lockres " | |
597 | "(blocked = %d\n", hi); | |
598 | ||
599 | if (lock->ml.node != dlm->node_num) { | |
600 | ret = dlm_send_proxy_bast(dlm, res, lock, hi); | |
601 | if (ret < 0) | |
602 | mlog_errno(ret); | |
603 | } else | |
604 | dlm_do_local_bast(dlm, res, lock, hi); | |
605 | ||
606 | spin_lock(&dlm->ast_lock); | |
607 | ||
608 | /* possible that another bast was queued while | |
609 | * we were delivering the last one */ | |
610 | if (!list_empty(&lock->bast_list)) { | |
611 | mlog(0, "aha another bast got queued while " | |
612 | "we were finishing the last one. will " | |
613 | "keep the bast_pending flag set.\n"); | |
614 | } else | |
615 | lock->bast_pending = 0; | |
616 | ||
617 | /* drop the extra ref. | |
618 | * this may drop it completely. */ | |
619 | dlm_lock_put(lock); | |
620 | dlm_lockres_release_ast(dlm, res); | |
621 | } | |
622 | wake_up(&dlm->ast_wq); | |
623 | spin_unlock(&dlm->ast_lock); | |
624 | } | |
625 | ||
626 | ||
627 | #define DLM_THREAD_TIMEOUT_MS (4 * 1000) | |
628 | #define DLM_THREAD_MAX_DIRTY 100 | |
629 | #define DLM_THREAD_MAX_ASTS 10 | |
630 | ||
631 | static int dlm_thread(void *data) | |
632 | { | |
633 | struct dlm_lock_resource *res; | |
634 | struct dlm_ctxt *dlm = data; | |
635 | unsigned long timeout = msecs_to_jiffies(DLM_THREAD_TIMEOUT_MS); | |
636 | ||
637 | mlog(0, "dlm thread running for %s...\n", dlm->name); | |
638 | ||
639 | while (!kthread_should_stop()) { | |
640 | int n = DLM_THREAD_MAX_DIRTY; | |
641 | ||
642 | /* dlm_shutting_down is very point-in-time, but that | |
643 | * doesn't matter as we'll just loop back around if we | |
644 | * get false on the leading edge of a state | |
645 | * transition. */ | |
646 | dlm_run_purge_list(dlm, dlm_shutting_down(dlm)); | |
647 | ||
648 | /* We really don't want to hold dlm->spinlock while | |
649 | * calling dlm_shuffle_lists on each lockres that | |
650 | * needs to have its queues adjusted and AST/BASTs | |
651 | * run. So let's pull each entry off the dirty_list | |
652 | * and drop dlm->spinlock ASAP. Once off the list, | |
653 | * res->spinlock needs to be taken again to protect | |
654 | * the queues while calling dlm_shuffle_lists. */ | |
655 | spin_lock(&dlm->spinlock); | |
656 | while (!list_empty(&dlm->dirty_list)) { | |
657 | int delay = 0; | |
658 | res = list_entry(dlm->dirty_list.next, | |
659 | struct dlm_lock_resource, dirty); | |
660 | ||
661 | /* peel a lockres off, remove it from the list, | |
662 | * unset the dirty flag and drop the dlm lock */ | |
663 | BUG_ON(!res); | |
664 | dlm_lockres_get(res); | |
665 | ||
666 | spin_lock(&res->spinlock); | |
ddc09c8d | 667 | /* We clear the DLM_LOCK_RES_DIRTY state once we shuffle lists below */ |
6714d8e8 KH |
668 | list_del_init(&res->dirty); |
669 | spin_unlock(&res->spinlock); | |
670 | spin_unlock(&dlm->spinlock); | |
6ff06a93 KH |
671 | /* Drop dirty_list ref */ |
672 | dlm_lockres_put(res); | |
6714d8e8 KH |
673 | |
674 | /* lockres can be re-dirtied/re-added to the | |
675 | * dirty_list in this gap, but that is ok */ | |
676 | ||
677 | spin_lock(&res->spinlock); | |
678 | if (res->owner != dlm->node_num) { | |
679 | __dlm_print_one_lock_resource(res); | |
680 | mlog(ML_ERROR, "inprog:%s, mig:%s, reco:%s, dirty:%s\n", | |
681 | res->state & DLM_LOCK_RES_IN_PROGRESS ? "yes" : "no", | |
682 | res->state & DLM_LOCK_RES_MIGRATING ? "yes" : "no", | |
683 | res->state & DLM_LOCK_RES_RECOVERING ? "yes" : "no", | |
684 | res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no"); | |
685 | } | |
686 | BUG_ON(res->owner != dlm->node_num); | |
687 | ||
688 | /* it is now ok to move lockreses in these states | |
689 | * to the dirty list, assuming that they will only be | |
690 | * dirty for a short while. */ | |
ddc09c8d | 691 | BUG_ON(res->state & DLM_LOCK_RES_MIGRATING); |
6714d8e8 | 692 | if (res->state & (DLM_LOCK_RES_IN_PROGRESS | |
6714d8e8 KH |
693 | DLM_LOCK_RES_RECOVERING)) { |
694 | /* move it to the tail and keep going */ | |
ddc09c8d | 695 | res->state &= ~DLM_LOCK_RES_DIRTY; |
6714d8e8 KH |
696 | spin_unlock(&res->spinlock); |
697 | mlog(0, "delaying list shuffling for in-" | |
698 | "progress lockres %.*s, state=%d\n", | |
699 | res->lockname.len, res->lockname.name, | |
700 | res->state); | |
701 | delay = 1; | |
702 | goto in_progress; | |
703 | } | |
704 | ||
705 | /* at this point the lockres is not migrating/ | |
706 | * recovering/in-progress. we have the lockres | |
707 | * spinlock and do NOT have the dlm lock. | |
708 | * safe to reserve/queue asts and run the lists. */ | |
709 | ||
8d79d088 KH |
710 | mlog(0, "calling dlm_shuffle_lists with dlm=%s, " |
711 | "res=%.*s\n", dlm->name, | |
712 | res->lockname.len, res->lockname.name); | |
6714d8e8 KH |
713 | |
714 | /* called while holding lockres lock */ | |
715 | dlm_shuffle_lists(dlm, res); | |
ddc09c8d | 716 | res->state &= ~DLM_LOCK_RES_DIRTY; |
6714d8e8 KH |
717 | spin_unlock(&res->spinlock); |
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 | } |