Commit | Line | Data |
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d7e09d03 PT |
1 | /* |
2 | * GPL HEADER START | |
3 | * | |
4 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 only, | |
8 | * as published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, but | |
11 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 | * General Public License version 2 for more details (a copy is included | |
14 | * in the LICENSE file that accompanied this code). | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * version 2 along with this program; If not, see | |
6a5b99a4 | 18 | * http://www.gnu.org/licenses/gpl-2.0.html |
d7e09d03 | 19 | * |
d7e09d03 PT |
20 | * GPL HEADER END |
21 | */ | |
22 | /* | |
23 | * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. | |
24 | * Use is subject to license terms. | |
25 | * | |
1dc563a6 | 26 | * Copyright (c) 2011, 2015, Intel Corporation. |
d7e09d03 PT |
27 | */ |
28 | /* | |
29 | * This file is part of Lustre, http://www.lustre.org/ | |
30 | * Lustre is a trademark of Sun Microsystems, Inc. | |
31 | * | |
32 | * lustre/ptlrpc/ptlrpcd.c | |
33 | */ | |
34 | ||
35 | /** \defgroup ptlrpcd PortalRPC daemon | |
36 | * | |
37 | * ptlrpcd is a special thread with its own set where other user might add | |
38 | * requests when they don't want to wait for their completion. | |
39 | * PtlRPCD will take care of sending such requests and then processing their | |
40 | * replies and calling completion callbacks as necessary. | |
41 | * The callbacks are called directly from ptlrpcd context. | |
42 | * It is important to never significantly block (esp. on RPCs!) within such | |
43 | * completion handler or a deadlock might occur where ptlrpcd enters some | |
44 | * callback that attempts to send another RPC and wait for it to return, | |
45 | * during which time ptlrpcd is completely blocked, so e.g. if import | |
46 | * fails, recovery cannot progress because connection requests are also | |
47 | * sent by ptlrpcd. | |
48 | * | |
49 | * @{ | |
50 | */ | |
51 | ||
52 | #define DEBUG_SUBSYSTEM S_RPC | |
53 | ||
9fdaf8c0 | 54 | #include "../../include/linux/libcfs/libcfs.h" |
d7e09d03 | 55 | |
e27db149 GKH |
56 | #include "../include/lustre_net.h" |
57 | #include "../include/lustre_lib.h" | |
58 | #include "../include/lustre_ha.h" | |
59 | #include "../include/obd_class.h" /* for obd_zombie */ | |
60 | #include "../include/obd_support.h" /* for OBD_FAIL_CHECK */ | |
61 | #include "../include/cl_object.h" /* cl_env_{get,put}() */ | |
62 | #include "../include/lprocfs_status.h" | |
d7e09d03 PT |
63 | |
64 | #include "ptlrpc_internal.h" | |
65 | ||
c5c4c6fa | 66 | /* One of these per CPT. */ |
d7e09d03 | 67 | struct ptlrpcd { |
d0bfef31 CH |
68 | int pd_size; |
69 | int pd_index; | |
c5c4c6fa OW |
70 | int pd_cpt; |
71 | int pd_cursor; | |
d0bfef31 | 72 | int pd_nthreads; |
c5c4c6fa | 73 | int pd_groupsize; |
d7e09d03 PT |
74 | struct ptlrpcd_ctl pd_threads[0]; |
75 | }; | |
76 | ||
c5c4c6fa OW |
77 | /* |
78 | * max_ptlrpcds is obsolete, but retained to ensure that the kernel | |
79 | * module will load on a system where it has been tuned. | |
80 | * A value other than 0 implies it was tuned, in which case the value | |
81 | * is used to derive a setting for ptlrpcd_per_cpt_max. | |
82 | */ | |
d7e09d03 | 83 | static int max_ptlrpcds; |
8cc7b4b9 PT |
84 | module_param(max_ptlrpcds, int, 0644); |
85 | MODULE_PARM_DESC(max_ptlrpcds, "Max ptlrpcd thread count to be started."); | |
d7e09d03 | 86 | |
c5c4c6fa OW |
87 | /* |
88 | * ptlrpcd_bind_policy is obsolete, but retained to ensure that | |
89 | * the kernel module will load on a system where it has been tuned. | |
90 | * A value other than 0 implies it was tuned, in which case the value | |
91 | * is used to derive a setting for ptlrpcd_partner_group_size. | |
92 | */ | |
93 | static int ptlrpcd_bind_policy; | |
8cc7b4b9 | 94 | module_param(ptlrpcd_bind_policy, int, 0644); |
c5c4c6fa OW |
95 | MODULE_PARM_DESC(ptlrpcd_bind_policy, |
96 | "Ptlrpcd threads binding mode (obsolete)."); | |
97 | ||
98 | /* | |
99 | * ptlrpcd_per_cpt_max: The maximum number of ptlrpcd threads to run | |
100 | * in a CPT. | |
101 | */ | |
102 | static int ptlrpcd_per_cpt_max; | |
103 | module_param(ptlrpcd_per_cpt_max, int, 0644); | |
104 | MODULE_PARM_DESC(ptlrpcd_per_cpt_max, | |
105 | "Max ptlrpcd thread count to be started per cpt."); | |
106 | ||
107 | /* | |
108 | * ptlrpcd_partner_group_size: The desired number of threads in each | |
109 | * ptlrpcd partner thread group. Default is 2, corresponding to the | |
110 | * old PDB_POLICY_PAIR. A negative value makes all ptlrpcd threads in | |
111 | * a CPT partners of each other. | |
112 | */ | |
113 | static int ptlrpcd_partner_group_size; | |
114 | module_param(ptlrpcd_partner_group_size, int, 0644); | |
115 | MODULE_PARM_DESC(ptlrpcd_partner_group_size, | |
116 | "Number of ptlrpcd threads in a partner group."); | |
117 | ||
118 | /* | |
119 | * ptlrpcd_cpts: A CPT string describing the CPU partitions that | |
120 | * ptlrpcd threads should run on. Used to make ptlrpcd threads run on | |
121 | * a subset of all CPTs. | |
122 | * | |
123 | * ptlrpcd_cpts=2 | |
124 | * ptlrpcd_cpts=[2] | |
125 | * run ptlrpcd threads only on CPT 2. | |
126 | * | |
127 | * ptlrpcd_cpts=0-3 | |
128 | * ptlrpcd_cpts=[0-3] | |
129 | * run ptlrpcd threads on CPTs 0, 1, 2, and 3. | |
130 | * | |
131 | * ptlrpcd_cpts=[0-3,5,7] | |
132 | * run ptlrpcd threads on CPTS 0, 1, 2, 3, 5, and 7. | |
133 | */ | |
134 | static char *ptlrpcd_cpts; | |
135 | module_param(ptlrpcd_cpts, charp, 0644); | |
136 | MODULE_PARM_DESC(ptlrpcd_cpts, | |
137 | "CPU partitions ptlrpcd threads should run in"); | |
138 | ||
139 | /* ptlrpcds_cpt_idx maps cpt numbers to an index in the ptlrpcds array. */ | |
140 | static int *ptlrpcds_cpt_idx; | |
141 | ||
142 | /* ptlrpcds_num is the number of entries in the ptlrpcds array. */ | |
143 | static int ptlrpcds_num; | |
144 | static struct ptlrpcd **ptlrpcds; | |
145 | ||
146 | /* | |
147 | * In addition to the regular thread pool above, there is a single | |
148 | * global recovery thread. Recovery isn't critical for performance, | |
149 | * and doesn't block, but must always be able to proceed, and it is | |
150 | * possible that all normal ptlrpcd threads are blocked. Hence the | |
151 | * need for a dedicated thread. | |
152 | */ | |
153 | static struct ptlrpcd_ctl ptlrpcd_rcv; | |
d7e09d03 PT |
154 | |
155 | struct mutex ptlrpcd_mutex; | |
225f597c | 156 | static int ptlrpcd_users; |
d7e09d03 PT |
157 | |
158 | void ptlrpcd_wake(struct ptlrpc_request *req) | |
159 | { | |
32c8728d | 160 | struct ptlrpc_request_set *set = req->rq_set; |
d7e09d03 | 161 | |
32c8728d | 162 | wake_up(&set->set_waitq); |
d7e09d03 PT |
163 | } |
164 | EXPORT_SYMBOL(ptlrpcd_wake); | |
165 | ||
166 | static struct ptlrpcd_ctl * | |
c5c4c6fa | 167 | ptlrpcd_select_pc(struct ptlrpc_request *req) |
d7e09d03 | 168 | { |
c5c4c6fa OW |
169 | struct ptlrpcd *pd; |
170 | int cpt; | |
171 | int idx; | |
d7e09d03 | 172 | |
8b382089 | 173 | if (req && req->rq_send_state != LUSTRE_IMP_FULL) |
c5c4c6fa OW |
174 | return &ptlrpcd_rcv; |
175 | ||
176 | cpt = cfs_cpt_current(cfs_cpt_table, 1); | |
177 | if (!ptlrpcds_cpt_idx) | |
178 | idx = cpt; | |
179 | else | |
180 | idx = ptlrpcds_cpt_idx[cpt]; | |
181 | pd = ptlrpcds[idx]; | |
182 | ||
d7e09d03 | 183 | /* We do not care whether it is strict load balance. */ |
c5c4c6fa OW |
184 | idx = pd->pd_cursor; |
185 | if (++idx == pd->pd_nthreads) | |
186 | idx = 0; | |
187 | pd->pd_cursor = idx; | |
d7e09d03 | 188 | |
c5c4c6fa | 189 | return &pd->pd_threads[idx]; |
d7e09d03 PT |
190 | } |
191 | ||
d7e09d03 PT |
192 | /** |
193 | * Return transferred RPCs count. | |
194 | */ | |
195 | static int ptlrpcd_steal_rqset(struct ptlrpc_request_set *des, | |
196 | struct ptlrpc_request_set *src) | |
197 | { | |
198 | struct list_head *tmp, *pos; | |
199 | struct ptlrpc_request *req; | |
200 | int rc = 0; | |
201 | ||
202 | spin_lock(&src->set_new_req_lock); | |
203 | if (likely(!list_empty(&src->set_new_requests))) { | |
204 | list_for_each_safe(pos, tmp, &src->set_new_requests) { | |
205 | req = list_entry(pos, struct ptlrpc_request, | |
30c0aa39 | 206 | rq_set_chain); |
d7e09d03 PT |
207 | req->rq_set = des; |
208 | } | |
30c0aa39 | 209 | list_splice_init(&src->set_new_requests, &des->set_requests); |
d7e09d03 PT |
210 | rc = atomic_read(&src->set_new_count); |
211 | atomic_add(rc, &des->set_remaining); | |
212 | atomic_set(&src->set_new_count, 0); | |
213 | } | |
214 | spin_unlock(&src->set_new_req_lock); | |
215 | return rc; | |
216 | } | |
217 | ||
218 | /** | |
219 | * Requests that are added to the ptlrpcd queue are sent via | |
220 | * ptlrpcd_check->ptlrpc_check_set(). | |
221 | */ | |
c5c4c6fa | 222 | void ptlrpcd_add_req(struct ptlrpc_request *req) |
d7e09d03 PT |
223 | { |
224 | struct ptlrpcd_ctl *pc; | |
225 | ||
226 | if (req->rq_reqmsg) | |
227 | lustre_msg_set_jobid(req->rq_reqmsg, NULL); | |
228 | ||
229 | spin_lock(&req->rq_lock); | |
230 | if (req->rq_invalid_rqset) { | |
231 | struct l_wait_info lwi = LWI_TIMEOUT(cfs_time_seconds(5), | |
232 | back_to_sleep, NULL); | |
233 | ||
234 | req->rq_invalid_rqset = 0; | |
235 | spin_unlock(&req->rq_lock); | |
8b382089 | 236 | l_wait_event(req->rq_set_waitq, !req->rq_set, &lwi); |
d7e09d03 | 237 | } else if (req->rq_set) { |
b6da17f3 | 238 | /* If we have a valid "rq_set", just reuse it to avoid double |
dadfcdab OD |
239 | * linked. |
240 | */ | |
d7e09d03 PT |
241 | LASSERT(req->rq_phase == RQ_PHASE_NEW); |
242 | LASSERT(req->rq_send_state == LUSTRE_IMP_REPLAY); | |
243 | ||
244 | /* ptlrpc_check_set will decrease the count */ | |
245 | atomic_inc(&req->rq_set->set_remaining); | |
246 | spin_unlock(&req->rq_lock); | |
247 | wake_up(&req->rq_set->set_waitq); | |
248 | return; | |
249 | } else { | |
250 | spin_unlock(&req->rq_lock); | |
251 | } | |
252 | ||
c5c4c6fa | 253 | pc = ptlrpcd_select_pc(req); |
d7e09d03 PT |
254 | |
255 | DEBUG_REQ(D_INFO, req, "add req [%p] to pc [%s:%d]", | |
256 | req, pc->pc_name, pc->pc_index); | |
257 | ||
258 | ptlrpc_set_add_new_req(pc, req); | |
259 | } | |
260 | EXPORT_SYMBOL(ptlrpcd_add_req); | |
261 | ||
262 | static inline void ptlrpc_reqset_get(struct ptlrpc_request_set *set) | |
263 | { | |
264 | atomic_inc(&set->set_refcount); | |
265 | } | |
266 | ||
267 | /** | |
268 | * Check if there is more work to do on ptlrpcd set. | |
269 | * Returns 1 if yes. | |
270 | */ | |
271 | static int ptlrpcd_check(struct lu_env *env, struct ptlrpcd_ctl *pc) | |
272 | { | |
273 | struct list_head *tmp, *pos; | |
274 | struct ptlrpc_request *req; | |
275 | struct ptlrpc_request_set *set = pc->pc_set; | |
276 | int rc = 0; | |
277 | int rc2; | |
d7e09d03 PT |
278 | |
279 | if (atomic_read(&set->set_new_count)) { | |
280 | spin_lock(&set->set_new_req_lock); | |
281 | if (likely(!list_empty(&set->set_new_requests))) { | |
282 | list_splice_init(&set->set_new_requests, | |
30c0aa39 | 283 | &set->set_requests); |
d7e09d03 | 284 | atomic_add(atomic_read(&set->set_new_count), |
30c0aa39 | 285 | &set->set_remaining); |
d7e09d03 PT |
286 | atomic_set(&set->set_new_count, 0); |
287 | /* | |
288 | * Need to calculate its timeout. | |
289 | */ | |
290 | rc = 1; | |
291 | } | |
292 | spin_unlock(&set->set_new_req_lock); | |
293 | } | |
294 | ||
295 | /* We should call lu_env_refill() before handling new requests to make | |
296 | * sure that env key the requests depending on really exists. | |
297 | */ | |
298 | rc2 = lu_env_refill(env); | |
299 | if (rc2 != 0) { | |
300 | /* | |
301 | * XXX This is very awkward situation, because | |
302 | * execution can neither continue (request | |
303 | * interpreters assume that env is set up), nor repeat | |
304 | * the loop (as this potentially results in a tight | |
305 | * loop of -ENOMEM's). | |
306 | * | |
307 | * Fortunately, refill only ever does something when | |
308 | * new modules are loaded, i.e., early during boot up. | |
309 | */ | |
310 | CERROR("Failure to refill session: %d\n", rc2); | |
0a3bdb00 | 311 | return rc; |
d7e09d03 PT |
312 | } |
313 | ||
314 | if (atomic_read(&set->set_remaining)) | |
315 | rc |= ptlrpc_check_set(env, set); | |
316 | ||
fa55c6a4 | 317 | /* NB: ptlrpc_check_set has already moved completed request at the |
dadfcdab OD |
318 | * head of seq::set_requests |
319 | */ | |
fa55c6a4 LZ |
320 | list_for_each_safe(pos, tmp, &set->set_requests) { |
321 | req = list_entry(pos, struct ptlrpc_request, rq_set_chain); | |
322 | if (req->rq_phase != RQ_PHASE_COMPLETE) | |
323 | break; | |
d7e09d03 | 324 | |
fa55c6a4 LZ |
325 | list_del_init(&req->rq_set_chain); |
326 | req->rq_set = NULL; | |
327 | ptlrpc_req_finished(req); | |
d7e09d03 PT |
328 | } |
329 | ||
330 | if (rc == 0) { | |
331 | /* | |
332 | * If new requests have been added, make sure to wake up. | |
333 | */ | |
334 | rc = atomic_read(&set->set_new_count); | |
335 | ||
336 | /* If we have nothing to do, check whether we can take some | |
dadfcdab OD |
337 | * work from our partner threads. |
338 | */ | |
d7e09d03 PT |
339 | if (rc == 0 && pc->pc_npartners > 0) { |
340 | struct ptlrpcd_ctl *partner; | |
341 | struct ptlrpc_request_set *ps; | |
342 | int first = pc->pc_cursor; | |
343 | ||
344 | do { | |
345 | partner = pc->pc_partners[pc->pc_cursor++]; | |
346 | if (pc->pc_cursor >= pc->pc_npartners) | |
347 | pc->pc_cursor = 0; | |
8b382089 | 348 | if (!partner) |
d7e09d03 PT |
349 | continue; |
350 | ||
351 | spin_lock(&partner->pc_lock); | |
352 | ps = partner->pc_set; | |
8b382089 | 353 | if (!ps) { |
d7e09d03 PT |
354 | spin_unlock(&partner->pc_lock); |
355 | continue; | |
356 | } | |
357 | ||
358 | ptlrpc_reqset_get(ps); | |
359 | spin_unlock(&partner->pc_lock); | |
360 | ||
361 | if (atomic_read(&ps->set_new_count)) { | |
362 | rc = ptlrpcd_steal_rqset(set, ps); | |
363 | if (rc > 0) | |
2d00bd17 JP |
364 | CDEBUG(D_RPCTRACE, "transfer %d async RPCs [%d->%d]\n", |
365 | rc, partner->pc_index, | |
366 | pc->pc_index); | |
d7e09d03 PT |
367 | } |
368 | ptlrpc_reqset_put(ps); | |
369 | } while (rc == 0 && pc->pc_cursor != first); | |
370 | } | |
371 | } | |
372 | ||
0a3bdb00 | 373 | return rc; |
d7e09d03 PT |
374 | } |
375 | ||
376 | /** | |
377 | * Main ptlrpcd thread. | |
378 | * ptlrpc's code paths like to execute in process context, so we have this | |
379 | * thread which spins on a set which contains the rpcs and sends them. | |
380 | * | |
381 | */ | |
382 | static int ptlrpcd(void *arg) | |
383 | { | |
384 | struct ptlrpcd_ctl *pc = arg; | |
c5c4c6fa | 385 | struct ptlrpc_request_set *set; |
2579d8d0 JX |
386 | struct lu_context ses = { 0 }; |
387 | struct lu_env env = { .le_ses = &ses }; | |
c5c4c6fa OW |
388 | int rc = 0; |
389 | int exit = 0; | |
d7e09d03 PT |
390 | |
391 | unshare_fs_struct(); | |
c5c4c6fa OW |
392 | if (cfs_cpt_bind(cfs_cpt_table, pc->pc_cpt) != 0) |
393 | CWARN("Failed to bind %s on CPT %d\n", pc->pc_name, pc->pc_cpt); | |
394 | ||
395 | /* | |
396 | * Allocate the request set after the thread has been bound | |
397 | * above. This is safe because no requests will be queued | |
398 | * until all ptlrpcd threads have confirmed that they have | |
399 | * successfully started. | |
400 | */ | |
401 | set = ptlrpc_prep_set(); | |
402 | if (!set) { | |
403 | rc = -ENOMEM; | |
404 | goto failed; | |
d7e09d03 | 405 | } |
c5c4c6fa OW |
406 | spin_lock(&pc->pc_lock); |
407 | pc->pc_set = set; | |
408 | spin_unlock(&pc->pc_lock); | |
d7e09d03 PT |
409 | /* |
410 | * XXX So far only "client" ptlrpcd uses an environment. In | |
411 | * the future, ptlrpcd thread (or a thread-set) has to given | |
412 | * an argument, describing its "scope". | |
413 | */ | |
414 | rc = lu_context_init(&env.le_ctx, | |
cd94f231 | 415 | LCT_CL_THREAD | LCT_REMEMBER | LCT_NOREF); |
2579d8d0 JX |
416 | if (rc == 0) { |
417 | rc = lu_context_init(env.le_ses, | |
418 | LCT_SESSION | LCT_REMEMBER | LCT_NOREF); | |
419 | if (rc != 0) | |
420 | lu_context_fini(&env.le_ctx); | |
421 | } | |
422 | ||
d7e09d03 | 423 | if (rc != 0) |
c5c4c6fa OW |
424 | goto failed; |
425 | ||
426 | complete(&pc->pc_starting); | |
d7e09d03 PT |
427 | |
428 | /* | |
429 | * This mainloop strongly resembles ptlrpc_set_wait() except that our | |
430 | * set never completes. ptlrpcd_check() calls ptlrpc_check_set() when | |
431 | * there are requests in the set. New requests come in on the set's | |
432 | * new_req_list and ptlrpcd_check() moves them into the set. | |
433 | */ | |
434 | do { | |
435 | struct l_wait_info lwi; | |
436 | int timeout; | |
437 | ||
438 | timeout = ptlrpc_set_next_timeout(set); | |
439 | lwi = LWI_TIMEOUT(cfs_time_seconds(timeout ? timeout : 1), | |
440 | ptlrpc_expired_set, set); | |
441 | ||
442 | lu_context_enter(&env.le_ctx); | |
2579d8d0 JX |
443 | lu_context_enter(env.le_ses); |
444 | l_wait_event(set->set_waitq, ptlrpcd_check(&env, pc), &lwi); | |
d7e09d03 | 445 | lu_context_exit(&env.le_ctx); |
2579d8d0 | 446 | lu_context_exit(env.le_ses); |
d7e09d03 PT |
447 | |
448 | /* | |
449 | * Abort inflight rpcs for forced stop case. | |
450 | */ | |
451 | if (test_bit(LIOD_STOP, &pc->pc_flags)) { | |
452 | if (test_bit(LIOD_FORCE, &pc->pc_flags)) | |
453 | ptlrpc_abort_set(set); | |
454 | exit++; | |
455 | } | |
456 | ||
457 | /* | |
458 | * Let's make one more loop to make sure that ptlrpcd_check() | |
459 | * copied all raced new rpcs into the set so we can kill them. | |
460 | */ | |
461 | } while (exit < 2); | |
462 | ||
463 | /* | |
464 | * Wait for inflight requests to drain. | |
465 | */ | |
466 | if (!list_empty(&set->set_requests)) | |
467 | ptlrpc_set_wait(set); | |
468 | lu_context_fini(&env.le_ctx); | |
2579d8d0 | 469 | lu_context_fini(env.le_ses); |
d7e09d03 PT |
470 | |
471 | complete(&pc->pc_finishing); | |
472 | ||
473 | return 0; | |
c5c4c6fa OW |
474 | failed: |
475 | pc->pc_error = rc; | |
476 | complete(&pc->pc_starting); | |
477 | return rc; | |
d7e09d03 PT |
478 | } |
479 | ||
c5c4c6fa OW |
480 | static void ptlrpcd_ctl_init(struct ptlrpcd_ctl *pc, int index, int cpt) |
481 | { | |
482 | pc->pc_index = index; | |
483 | pc->pc_cpt = cpt; | |
484 | init_completion(&pc->pc_starting); | |
485 | init_completion(&pc->pc_finishing); | |
486 | spin_lock_init(&pc->pc_lock); | |
487 | ||
488 | if (index < 0) { | |
489 | /* Recovery thread. */ | |
490 | snprintf(pc->pc_name, sizeof(pc->pc_name), "ptlrpcd_rcv"); | |
491 | } else { | |
492 | /* Regular thread. */ | |
493 | snprintf(pc->pc_name, sizeof(pc->pc_name), | |
494 | "ptlrpcd_%02d_%02d", cpt, index); | |
495 | } | |
496 | } | |
497 | ||
498 | /* XXX: We want multiple CPU cores to share the async RPC load. So we | |
499 | * start many ptlrpcd threads. We also want to reduce the ptlrpcd | |
500 | * overhead caused by data transfer cross-CPU cores. So we bind | |
501 | * all ptlrpcd threads to a CPT, in the expectation that CPTs | |
502 | * will be defined in a way that matches these boundaries. Within | |
503 | * a CPT a ptlrpcd thread can be scheduled on any available core. | |
d7e09d03 | 504 | * |
c5c4c6fa OW |
505 | * Each ptlrpcd thread has its own request queue. This can cause |
506 | * response delay if the thread is already busy. To help with | |
507 | * this we define partner threads: these are other threads bound | |
508 | * to the same CPT which will check for work in each other's | |
509 | * request queues if they have no work to do. | |
d7e09d03 | 510 | * |
c5c4c6fa OW |
511 | * The desired number of partner threads can be tuned by setting |
512 | * ptlrpcd_partner_group_size. The default is to create pairs of | |
513 | * partner threads. | |
d7e09d03 | 514 | */ |
c5c4c6fa | 515 | static int ptlrpcd_partners(struct ptlrpcd *pd, int index) |
d7e09d03 PT |
516 | { |
517 | struct ptlrpcd_ctl *pc; | |
c5c4c6fa OW |
518 | struct ptlrpcd_ctl **ppc; |
519 | int first; | |
520 | int i; | |
d7e09d03 | 521 | int rc = 0; |
c5c4c6fa OW |
522 | int size; |
523 | ||
524 | LASSERT(index >= 0 && index < pd->pd_nthreads); | |
525 | pc = &pd->pd_threads[index]; | |
526 | pc->pc_npartners = pd->pd_groupsize - 1; | |
527 | ||
528 | if (pc->pc_npartners <= 0) | |
529 | goto out; | |
d7e09d03 | 530 | |
c5c4c6fa OW |
531 | size = sizeof(struct ptlrpcd_ctl *) * pc->pc_npartners; |
532 | pc->pc_partners = kzalloc_node(size, GFP_NOFS, | |
533 | cfs_cpt_spread_node(cfs_cpt_table, | |
534 | pc->pc_cpt)); | |
535 | if (!pc->pc_partners) { | |
d7e09d03 | 536 | pc->pc_npartners = 0; |
c5c4c6fa OW |
537 | rc = -ENOMEM; |
538 | goto out; | |
d7e09d03 PT |
539 | } |
540 | ||
c5c4c6fa OW |
541 | first = index - index % pd->pd_groupsize; |
542 | ppc = pc->pc_partners; | |
543 | for (i = first; i < first + pd->pd_groupsize; i++) { | |
544 | if (i != index) | |
545 | *ppc++ = &pd->pd_threads[i]; | |
d7e09d03 | 546 | } |
c5c4c6fa | 547 | out: |
0a3bdb00 | 548 | return rc; |
d7e09d03 PT |
549 | } |
550 | ||
c5c4c6fa | 551 | int ptlrpcd_start(struct ptlrpcd_ctl *pc) |
d7e09d03 | 552 | { |
c5c4c6fa OW |
553 | struct task_struct *task; |
554 | int rc = 0; | |
d7e09d03 PT |
555 | |
556 | /* | |
557 | * Do not allow start second thread for one pc. | |
558 | */ | |
559 | if (test_and_set_bit(LIOD_START, &pc->pc_flags)) { | |
560 | CWARN("Starting second thread (%s) for same pc %p\n", | |
c5c4c6fa | 561 | pc->pc_name, pc); |
0a3bdb00 | 562 | return 0; |
d7e09d03 PT |
563 | } |
564 | ||
d7e09d03 PT |
565 | /* |
566 | * So far only "client" ptlrpcd uses an environment. In the future, | |
567 | * ptlrpcd thread (or a thread-set) has to be given an argument, | |
568 | * describing its "scope". | |
569 | */ | |
cd94f231 | 570 | rc = lu_context_init(&pc->pc_env.le_ctx, LCT_CL_THREAD | LCT_REMEMBER); |
d7e09d03 | 571 | if (rc != 0) |
c5c4c6fa | 572 | goto out; |
d7e09d03 | 573 | |
c5c4c6fa OW |
574 | task = kthread_run(ptlrpcd, pc, "%s", pc->pc_name); |
575 | if (IS_ERR(task)) { | |
576 | rc = PTR_ERR(task); | |
577 | goto out_set; | |
578 | } | |
d7e09d03 | 579 | |
c5c4c6fa OW |
580 | wait_for_completion(&pc->pc_starting); |
581 | rc = pc->pc_error; | |
582 | if (rc != 0) | |
583 | goto out_set; | |
d7e09d03 | 584 | |
87c7d315 DE |
585 | return 0; |
586 | ||
87c7d315 | 587 | out_set: |
8b382089 | 588 | if (pc->pc_set) { |
87c7d315 DE |
589 | struct ptlrpc_request_set *set = pc->pc_set; |
590 | ||
591 | spin_lock(&pc->pc_lock); | |
592 | pc->pc_set = NULL; | |
593 | spin_unlock(&pc->pc_lock); | |
594 | ptlrpc_set_destroy(set); | |
d7e09d03 | 595 | } |
c5c4c6fa | 596 | lu_context_fini(&pc->pc_env.le_ctx); |
87c7d315 DE |
597 | |
598 | out: | |
599 | clear_bit(LIOD_START, &pc->pc_flags); | |
0a3bdb00 | 600 | return rc; |
d7e09d03 PT |
601 | } |
602 | ||
603 | void ptlrpcd_stop(struct ptlrpcd_ctl *pc, int force) | |
604 | { | |
d7e09d03 PT |
605 | if (!test_bit(LIOD_START, &pc->pc_flags)) { |
606 | CWARN("Thread for pc %p was not started\n", pc); | |
23f14e79 | 607 | return; |
d7e09d03 PT |
608 | } |
609 | ||
610 | set_bit(LIOD_STOP, &pc->pc_flags); | |
611 | if (force) | |
612 | set_bit(LIOD_FORCE, &pc->pc_flags); | |
613 | wake_up(&pc->pc_set->set_waitq); | |
d7e09d03 PT |
614 | } |
615 | ||
616 | void ptlrpcd_free(struct ptlrpcd_ctl *pc) | |
617 | { | |
618 | struct ptlrpc_request_set *set = pc->pc_set; | |
d7e09d03 PT |
619 | |
620 | if (!test_bit(LIOD_START, &pc->pc_flags)) { | |
621 | CWARN("Thread for pc %p was not started\n", pc); | |
622 | goto out; | |
623 | } | |
624 | ||
625 | wait_for_completion(&pc->pc_finishing); | |
626 | lu_context_fini(&pc->pc_env.le_ctx); | |
627 | ||
628 | spin_lock(&pc->pc_lock); | |
629 | pc->pc_set = NULL; | |
630 | spin_unlock(&pc->pc_lock); | |
631 | ptlrpc_set_destroy(set); | |
632 | ||
633 | clear_bit(LIOD_START, &pc->pc_flags); | |
634 | clear_bit(LIOD_STOP, &pc->pc_flags); | |
635 | clear_bit(LIOD_FORCE, &pc->pc_flags); | |
d7e09d03 PT |
636 | |
637 | out: | |
638 | if (pc->pc_npartners > 0) { | |
8b382089 | 639 | LASSERT(pc->pc_partners); |
d7e09d03 | 640 | |
9ae10597 | 641 | kfree(pc->pc_partners); |
d7e09d03 PT |
642 | pc->pc_partners = NULL; |
643 | } | |
644 | pc->pc_npartners = 0; | |
c5c4c6fa | 645 | pc->pc_error = 0; |
d7e09d03 PT |
646 | } |
647 | ||
648 | static void ptlrpcd_fini(void) | |
649 | { | |
650 | int i; | |
c5c4c6fa | 651 | int j; |
d7e09d03 | 652 | |
8b382089 | 653 | if (ptlrpcds) { |
c5c4c6fa OW |
654 | for (i = 0; i < ptlrpcds_num; i++) { |
655 | if (!ptlrpcds[i]) | |
656 | break; | |
657 | for (j = 0; j < ptlrpcds[i]->pd_nthreads; j++) | |
658 | ptlrpcd_stop(&ptlrpcds[i]->pd_threads[j], 0); | |
659 | for (j = 0; j < ptlrpcds[i]->pd_nthreads; j++) | |
660 | ptlrpcd_free(&ptlrpcds[i]->pd_threads[j]); | |
661 | kfree(ptlrpcds[i]); | |
662 | ptlrpcds[i] = NULL; | |
663 | } | |
9ae10597 | 664 | kfree(ptlrpcds); |
d7e09d03 | 665 | } |
c5c4c6fa OW |
666 | ptlrpcds_num = 0; |
667 | ||
668 | ptlrpcd_stop(&ptlrpcd_rcv, 0); | |
669 | ptlrpcd_free(&ptlrpcd_rcv); | |
670 | ||
671 | kfree(ptlrpcds_cpt_idx); | |
672 | ptlrpcds_cpt_idx = NULL; | |
d7e09d03 PT |
673 | } |
674 | ||
675 | static int ptlrpcd_init(void) | |
676 | { | |
c5c4c6fa OW |
677 | int nthreads; |
678 | int groupsize; | |
679 | int size; | |
680 | int i; | |
681 | int j; | |
682 | int rc = 0; | |
683 | struct cfs_cpt_table *cptable; | |
684 | __u32 *cpts = NULL; | |
685 | int ncpts; | |
686 | int cpt; | |
687 | struct ptlrpcd *pd; | |
688 | ||
689 | /* | |
690 | * Determine the CPTs that ptlrpcd threads will run on. | |
691 | */ | |
692 | cptable = cfs_cpt_table; | |
693 | ncpts = cfs_cpt_number(cptable); | |
694 | if (ptlrpcd_cpts) { | |
695 | struct cfs_expr_list *el; | |
696 | ||
697 | size = ncpts * sizeof(ptlrpcds_cpt_idx[0]); | |
698 | ptlrpcds_cpt_idx = kzalloc(size, GFP_KERNEL); | |
699 | if (!ptlrpcds_cpt_idx) { | |
700 | rc = -ENOMEM; | |
701 | goto out; | |
702 | } | |
703 | ||
704 | rc = cfs_expr_list_parse(ptlrpcd_cpts, | |
705 | strlen(ptlrpcd_cpts), | |
706 | 0, ncpts - 1, &el); | |
707 | ||
708 | if (rc != 0) { | |
709 | CERROR("ptlrpcd_cpts: invalid CPT pattern string: %s", | |
710 | ptlrpcd_cpts); | |
711 | rc = -EINVAL; | |
712 | goto out; | |
713 | } | |
714 | ||
715 | rc = cfs_expr_list_values(el, ncpts, &cpts); | |
716 | cfs_expr_list_free(el); | |
717 | if (rc <= 0) { | |
718 | CERROR("ptlrpcd_cpts: failed to parse CPT array %s: %d\n", | |
719 | ptlrpcd_cpts, rc); | |
720 | if (rc == 0) | |
721 | rc = -EINVAL; | |
722 | goto out; | |
723 | } | |
724 | ||
725 | /* | |
726 | * Create the cpt-to-index map. When there is no match | |
727 | * in the cpt table, pick a cpt at random. This could | |
728 | * be changed to take the topology of the system into | |
729 | * account. | |
730 | */ | |
731 | for (cpt = 0; cpt < ncpts; cpt++) { | |
732 | for (i = 0; i < rc; i++) | |
733 | if (cpts[i] == cpt) | |
734 | break; | |
735 | if (i >= rc) | |
736 | i = cpt % rc; | |
737 | ptlrpcds_cpt_idx[cpt] = i; | |
738 | } | |
739 | ||
740 | cfs_expr_list_values_free(cpts, rc); | |
741 | ncpts = rc; | |
742 | } | |
743 | ptlrpcds_num = ncpts; | |
744 | ||
745 | size = ncpts * sizeof(ptlrpcds[0]); | |
746 | ptlrpcds = kzalloc(size, GFP_KERNEL); | |
597851ac | 747 | if (!ptlrpcds) { |
a9b3e8f3 JL |
748 | rc = -ENOMEM; |
749 | goto out; | |
750 | } | |
d7e09d03 | 751 | |
c5c4c6fa OW |
752 | /* |
753 | * The max_ptlrpcds parameter is obsolete, but do something | |
754 | * sane if it has been tuned, and complain if | |
755 | * ptlrpcd_per_cpt_max has also been tuned. | |
756 | */ | |
757 | if (max_ptlrpcds != 0) { | |
758 | CWARN("max_ptlrpcds is obsolete.\n"); | |
759 | if (ptlrpcd_per_cpt_max == 0) { | |
760 | ptlrpcd_per_cpt_max = max_ptlrpcds / ncpts; | |
761 | /* Round up if there is a remainder. */ | |
762 | if (max_ptlrpcds % ncpts != 0) | |
763 | ptlrpcd_per_cpt_max++; | |
764 | CWARN("Setting ptlrpcd_per_cpt_max = %d\n", | |
765 | ptlrpcd_per_cpt_max); | |
766 | } else { | |
767 | CWARN("ptlrpd_per_cpt_max is also set!\n"); | |
768 | } | |
769 | } | |
770 | ||
771 | /* | |
772 | * The ptlrpcd_bind_policy parameter is obsolete, but do | |
773 | * something sane if it has been tuned, and complain if | |
774 | * ptlrpcd_partner_group_size is also tuned. | |
775 | */ | |
776 | if (ptlrpcd_bind_policy != 0) { | |
777 | CWARN("ptlrpcd_bind_policy is obsolete.\n"); | |
778 | if (ptlrpcd_partner_group_size == 0) { | |
779 | switch (ptlrpcd_bind_policy) { | |
780 | case 1: /* PDB_POLICY_NONE */ | |
781 | case 2: /* PDB_POLICY_FULL */ | |
782 | ptlrpcd_partner_group_size = 1; | |
783 | break; | |
784 | case 3: /* PDB_POLICY_PAIR */ | |
785 | ptlrpcd_partner_group_size = 2; | |
786 | break; | |
787 | case 4: /* PDB_POLICY_NEIGHBOR */ | |
788 | #ifdef CONFIG_NUMA | |
789 | ptlrpcd_partner_group_size = -1; /* CPT */ | |
790 | #else | |
791 | ptlrpcd_partner_group_size = 3; /* Triplets */ | |
792 | #endif | |
793 | break; | |
794 | default: /* Illegal value, use the default. */ | |
795 | ptlrpcd_partner_group_size = 2; | |
796 | break; | |
797 | } | |
798 | CWARN("Setting ptlrpcd_partner_group_size = %d\n", | |
799 | ptlrpcd_partner_group_size); | |
800 | } else { | |
801 | CWARN("ptlrpcd_partner_group_size is also set!\n"); | |
802 | } | |
803 | } | |
804 | ||
805 | if (ptlrpcd_partner_group_size == 0) | |
806 | ptlrpcd_partner_group_size = 2; | |
807 | else if (ptlrpcd_partner_group_size < 0) | |
808 | ptlrpcd_partner_group_size = -1; | |
809 | else if (ptlrpcd_per_cpt_max > 0 && | |
810 | ptlrpcd_partner_group_size > ptlrpcd_per_cpt_max) | |
811 | ptlrpcd_partner_group_size = ptlrpcd_per_cpt_max; | |
812 | ||
813 | /* | |
814 | * Start the recovery thread first. | |
815 | */ | |
816 | set_bit(LIOD_RECOVERY, &ptlrpcd_rcv.pc_flags); | |
817 | ptlrpcd_ctl_init(&ptlrpcd_rcv, -1, CFS_CPT_ANY); | |
818 | rc = ptlrpcd_start(&ptlrpcd_rcv); | |
d7e09d03 | 819 | if (rc < 0) |
a9b3e8f3 | 820 | goto out; |
d7e09d03 | 821 | |
c5c4c6fa OW |
822 | for (i = 0; i < ncpts; i++) { |
823 | if (!cpts) | |
824 | cpt = i; | |
825 | else | |
826 | cpt = cpts[i]; | |
827 | ||
828 | nthreads = cfs_cpt_weight(cptable, cpt); | |
829 | if (ptlrpcd_per_cpt_max > 0 && ptlrpcd_per_cpt_max < nthreads) | |
830 | nthreads = ptlrpcd_per_cpt_max; | |
831 | if (nthreads < 2) | |
832 | nthreads = 2; | |
833 | ||
834 | if (ptlrpcd_partner_group_size <= 0) { | |
835 | groupsize = nthreads; | |
836 | } else if (nthreads <= ptlrpcd_partner_group_size) { | |
837 | groupsize = nthreads; | |
838 | } else { | |
839 | groupsize = ptlrpcd_partner_group_size; | |
840 | if (nthreads % groupsize != 0) | |
841 | nthreads += groupsize - (nthreads % groupsize); | |
842 | } | |
843 | ||
844 | size = offsetof(struct ptlrpcd, pd_threads[nthreads]); | |
845 | pd = kzalloc_node(size, GFP_NOFS, | |
846 | cfs_cpt_spread_node(cfs_cpt_table, cpt)); | |
847 | if (!pd) { | |
848 | rc = -ENOMEM; | |
a9b3e8f3 | 849 | goto out; |
c5c4c6fa OW |
850 | } |
851 | pd->pd_size = size; | |
852 | pd->pd_index = i; | |
853 | pd->pd_cpt = cpt; | |
854 | pd->pd_cursor = 0; | |
855 | pd->pd_nthreads = nthreads; | |
856 | pd->pd_groupsize = groupsize; | |
857 | ptlrpcds[i] = pd; | |
d7e09d03 | 858 | |
c5c4c6fa OW |
859 | /* |
860 | * The ptlrpcd threads in a partner group can access | |
861 | * each other's struct ptlrpcd_ctl, so these must be | |
862 | * initialized before any thread is started. | |
863 | */ | |
864 | for (j = 0; j < nthreads; j++) { | |
865 | ptlrpcd_ctl_init(&pd->pd_threads[j], j, cpt); | |
866 | rc = ptlrpcd_partners(pd, j); | |
867 | if (rc < 0) | |
868 | goto out; | |
869 | } | |
d7e09d03 | 870 | |
c5c4c6fa OW |
871 | /* XXX: We start nthreads ptlrpc daemons. |
872 | * Each of them can process any non-recovery | |
873 | * async RPC to improve overall async RPC | |
874 | * efficiency. | |
875 | * | |
876 | * But there are some issues with async I/O RPCs | |
877 | * and async non-I/O RPCs processed in the same | |
878 | * set under some cases. The ptlrpcd may be | |
879 | * blocked by some async I/O RPC(s), then will | |
880 | * cause other async non-I/O RPC(s) can not be | |
881 | * processed in time. | |
882 | * | |
883 | * Maybe we should distinguish blocked async RPCs | |
884 | * from non-blocked async RPCs, and process them | |
885 | * in different ptlrpcd sets to avoid unnecessary | |
886 | * dependency. But how to distribute async RPCs | |
887 | * load among all the ptlrpc daemons becomes | |
888 | * another trouble. | |
889 | */ | |
890 | for (j = 0; j < nthreads; j++) { | |
891 | rc = ptlrpcd_start(&pd->pd_threads[j]); | |
892 | if (rc < 0) | |
893 | goto out; | |
894 | } | |
d7e09d03 | 895 | } |
c5c4c6fa OW |
896 | out: |
897 | if (rc != 0) | |
898 | ptlrpcd_fini(); | |
d7e09d03 | 899 | |
c5c4c6fa | 900 | return rc; |
d7e09d03 PT |
901 | } |
902 | ||
903 | int ptlrpcd_addref(void) | |
904 | { | |
905 | int rc = 0; | |
d7e09d03 PT |
906 | |
907 | mutex_lock(&ptlrpcd_mutex); | |
cc3b7758 | 908 | if (++ptlrpcd_users == 1) { |
d7e09d03 | 909 | rc = ptlrpcd_init(); |
cc3b7758 SP |
910 | if (rc < 0) |
911 | ptlrpcd_users--; | |
912 | } | |
d7e09d03 | 913 | mutex_unlock(&ptlrpcd_mutex); |
0a3bdb00 | 914 | return rc; |
d7e09d03 PT |
915 | } |
916 | EXPORT_SYMBOL(ptlrpcd_addref); | |
917 | ||
918 | void ptlrpcd_decref(void) | |
919 | { | |
920 | mutex_lock(&ptlrpcd_mutex); | |
921 | if (--ptlrpcd_users == 0) | |
922 | ptlrpcd_fini(); | |
923 | mutex_unlock(&ptlrpcd_mutex); | |
924 | } | |
925 | EXPORT_SYMBOL(ptlrpcd_decref); | |
926 | /** @} ptlrpcd */ |