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[fs/lustre-release.git] / lustre / ptlrpc / service.c
1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=8:tabstop=8:
3  *
4  *  Copyright (C) 2002 Cluster File Systems, Inc.
5  *
6  *   This file is part of Lustre, http://www.lustre.org.
7  *
8  *   Lustre is free software; you can redistribute it and/or
9  *   modify it under the terms of version 2 of the GNU General Public
10  *   License as published by the Free Software Foundation.
11  *
12  *   Lustre is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with Lustre; if not, write to the Free Software
19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  *
21  */
22
23 #define DEBUG_SUBSYSTEM S_RPC
24 #ifndef __KERNEL__
25 #include <liblustre.h>
26 #include <linux/kp30.h>
27 #endif
28 #include <linux/obd_support.h>
29 #include <linux/obd_class.h>
30 #include <linux/lustre_net.h>
31 #include <portals/types.h>
32 #include "ptlrpc_internal.h"
33
34 extern int request_in_callback(ptl_event_t *ev);
35
36 static int ptlrpc_check_event(struct ptlrpc_service *svc,
37                               struct ptlrpc_thread *thread, ptl_event_t *event)
38 {
39         struct ptlrpc_srv_ni *srv_ni;
40         int i, idx, rc;
41         ENTRY;
42
43         spin_lock(&svc->srv_lock);
44
45         if (thread->t_flags & SVC_STOPPING)
46                 GOTO(out, rc = 1);
47
48         LASSERT ((thread->t_flags & SVC_EVENT) == 0);
49         LASSERT (ptlrpc_ninterfaces > 0);
50
51         for (i = 0; i < ptlrpc_ninterfaces; i++) {
52                 idx = (svc->srv_interface_rover + i) % ptlrpc_ninterfaces;
53                 srv_ni = &svc->srv_interfaces[idx];
54
55                 LASSERT (!PtlHandleEqual (srv_ni->sni_eq_h, PTL_HANDLE_NONE));
56
57                 rc = PtlEQGet(srv_ni->sni_eq_h, event);
58                 switch (rc) {
59                 case PTL_OK:
60                         /* next time start with the next interface */
61                         svc->srv_interface_rover = (idx+1) % ptlrpc_ninterfaces;
62                         thread->t_flags |= SVC_EVENT;
63                         GOTO(out, rc = 1);
64
65                 case PTL_EQ_EMPTY:
66                         continue;
67
68                 case PTL_EQ_DROPPED:
69                         CWARN("Event queue overflow (bug 2125): timeouts will "
70                               "follow.\n");
71                         continue;
72
73                 default:
74                         CERROR("BUG: PtlEQGet returned %d\n", rc);
75                         LBUG();
76                 }
77         }
78         rc = 0;
79         EXIT;
80  out:
81         spin_unlock(&svc->srv_lock);
82         return rc;
83 }
84
85 struct ptlrpc_service * ptlrpc_init_svc(__u32 nevents, __u32 nbufs,
86                                         __u32 bufsize, __u32 max_req_size,
87                                         int req_portal, int rep_portal,
88                                         svc_handler_t handler, char *name,
89                                         struct proc_dir_entry *proc_entry)
90 {
91         int i, j, ssize, rc;
92         struct ptlrpc_service *service;
93         struct ptlrpc_srv_ni  *srv_ni;
94         ENTRY;
95
96         LASSERT (ptlrpc_ninterfaces > 0);
97
98         ssize = offsetof (struct ptlrpc_service,
99                           srv_interfaces[ptlrpc_ninterfaces]);
100         OBD_ALLOC(service, ssize);
101         if (service == NULL)
102                 RETURN(NULL);
103
104         service->srv_name = name;
105         spin_lock_init(&service->srv_lock);
106         INIT_LIST_HEAD(&service->srv_threads);
107         init_waitqueue_head(&service->srv_waitq);
108
109         service->srv_max_req_size = max_req_size;
110         service->srv_buf_size = bufsize;
111
112         service->srv_rep_portal = rep_portal;
113         service->srv_req_portal = req_portal;
114         service->srv_handler = handler;
115         service->srv_interface_rover = 0;
116
117         /* First initialise enough for early teardown */
118         for (i = 0; i < ptlrpc_ninterfaces; i++) {
119                 srv_ni = &service->srv_interfaces[i];
120
121                 srv_ni->sni_service = service;
122                 srv_ni->sni_ni = &ptlrpc_interfaces[i];
123                 srv_ni->sni_eq_h = PTL_HANDLE_NONE;
124                 INIT_LIST_HEAD(&srv_ni->sni_rqbds);
125                 srv_ni->sni_nrqbds = 0;
126                 atomic_set(&srv_ni->sni_nrqbds_receiving, 0);
127         }
128
129         /* Now allocate the event queue and request buffers, assuming all
130          * interfaces require the same level of buffering. */
131         for (i = 0; i < ptlrpc_ninterfaces; i++) {
132                 srv_ni = &service->srv_interfaces[i];
133                 CDEBUG (D_NET, "%s: initialising interface %s\n", name,
134                         srv_ni->sni_ni->pni_name);
135
136                 rc = PtlEQAlloc(srv_ni->sni_ni->pni_ni_h, nevents,
137                                 request_in_callback, &(srv_ni->sni_eq_h));
138                 if (rc != PTL_OK) {
139                         CERROR("%s.%d: PtlEQAlloc on %s failed: %d\n",
140                                name, i, srv_ni->sni_ni->pni_name, rc);
141                         GOTO (failed, NULL);
142                 }
143
144                 for (j = 0; j < nbufs; j++) {
145                         struct ptlrpc_request_buffer_desc *rqbd;
146
147                         OBD_ALLOC_WAIT(rqbd, sizeof(*rqbd));
148                         if (rqbd == NULL) {
149                                 CERROR ("%s.%d: Can't allocate request "
150                                         "descriptor %d on %s\n",
151                                         name, i, srv_ni->sni_nrqbds,
152                                         srv_ni->sni_ni->pni_name);
153                                 GOTO(failed, NULL);
154                         }
155
156                         rqbd->rqbd_srv_ni = srv_ni;
157                         rqbd->rqbd_me_h = PTL_HANDLE_NONE;
158                         atomic_set(&rqbd->rqbd_refcount, 0);
159
160                         OBD_ALLOC_WAIT(rqbd->rqbd_buffer, service->srv_buf_size);
161                         if (rqbd->rqbd_buffer == NULL) {
162                                 CERROR ("%s.%d: Can't allocate request "
163                                         "buffer %d on %s\n",
164                                         name, i, srv_ni->sni_nrqbds,
165                                         srv_ni->sni_ni->pni_name);
166                                 OBD_FREE(rqbd, sizeof(*rqbd));
167                                 GOTO(failed, NULL);
168                         }
169                         list_add(&rqbd->rqbd_list, &srv_ni->sni_rqbds);
170                         srv_ni->sni_nrqbds++;
171
172                         ptlrpc_link_svc_me(rqbd);
173                 }
174         }
175
176         if (proc_entry != NULL)
177                 ptlrpc_lprocfs_register_service(proc_entry, service);
178
179         CDEBUG(D_NET, "%s: Started on %d interfaces, listening on portal %d\n",
180                service->srv_name, ptlrpc_ninterfaces, service->srv_req_portal);
181
182         RETURN(service);
183 failed:
184         ptlrpc_unregister_service(service);
185         return NULL;
186 }
187
188 static int handle_incoming_request(struct obd_device *obddev,
189                                    struct ptlrpc_service *svc,
190                                    ptl_event_t *event,
191                                    struct ptlrpc_request *request)
192 {
193         struct ptlrpc_request_buffer_desc *rqbd = event->mem_desc.user_ptr;
194         int rc;
195
196         /* FIXME: If we move to an event-driven model, we should put the request
197          * on the stack of mds_handle instead. */
198
199         LASSERT (atomic_read (&rqbd->rqbd_refcount) > 0);
200         LASSERT ((event->mem_desc.options & (PTL_MD_IOV | PTL_MD_KIOV)) == 0);
201         LASSERT (rqbd->rqbd_srv_ni->sni_service == svc);
202         LASSERT (rqbd->rqbd_buffer == event->mem_desc.start);
203         LASSERT (event->offset + event->mlength <= svc->srv_buf_size);
204
205         memset(request, 0, sizeof(*request));
206         spin_lock_init (&request->rq_lock);
207         INIT_LIST_HEAD(&request->rq_list);
208         request->rq_svc = svc;
209         request->rq_obd = obddev;
210         request->rq_xid = event->match_bits;
211         request->rq_reqmsg = event->mem_desc.start + event->offset;
212         request->rq_reqlen = event->mlength;
213
214 #if SWAB_PARANOIA
215         /* Clear request swab mask; this is a new request */
216         request->rq_req_swab_mask = 0;
217 #endif
218         rc = lustre_unpack_msg (request->rq_reqmsg, request->rq_reqlen);
219         if (rc != 0) {
220                 CERROR ("error unpacking request: ptl %d from "LPX64
221                         " xid "LPU64"\n", svc->srv_req_portal,
222                        event->initiator.nid, request->rq_xid);
223                 goto out;
224         }
225         rc = -EINVAL;
226         if (request->rq_reqmsg->type != PTL_RPC_MSG_REQUEST) {
227                 CERROR("wrong packet type received (type=%u)\n",
228                        request->rq_reqmsg->type);
229                 goto out;
230         }
231
232         CDEBUG(D_NET, "got req "LPD64" (md: %p + %d)\n", request->rq_xid,
233                event->mem_desc.start, event->offset);
234
235         request->rq_peer.peer_nid = event->initiator.nid;
236         request->rq_peer.peer_ni = rqbd->rqbd_srv_ni->sni_ni;
237
238         request->rq_export = class_conn2export(&request->rq_reqmsg->handle);
239
240         if (request->rq_export) {
241                 request->rq_connection = request->rq_export->exp_connection;
242                 ptlrpc_connection_addref(request->rq_connection);
243                 if (request->rq_reqmsg->conn_cnt < 
244                     request->rq_export->exp_conn_cnt) {
245                         DEBUG_REQ(D_ERROR, request,
246                                   "DROPPING req from old connection %d < %d",
247                                   request->rq_reqmsg->conn_cnt,
248                                   request->rq_export->exp_conn_cnt);
249                         goto put_conn;
250                 }
251
252                 request->rq_export->exp_last_request_time =
253                         LTIME_S(CURRENT_TIME);
254         } else {
255                 /* create a (hopefully temporary) connection that will be used
256                  * to send the reply if this call doesn't create an export.
257                  * XXX revisit this when we revamp ptlrpc */
258                 request->rq_connection =
259                         ptlrpc_get_connection(&request->rq_peer, NULL);
260         }
261
262         CDEBUG(D_RPCTRACE, "Handling RPC pname:cluuid+ref:pid:xid:ni:nid:opc "
263                "%s:%s+%d:%d:"LPU64":%s:"LPX64":%d\n", current->comm,
264                (request->rq_export ?
265                 (char *)request->rq_export->exp_client_uuid.uuid : "0"),
266                (request->rq_export ?
267                 atomic_read(&request->rq_export->exp_refcount) : -99),
268                request->rq_reqmsg->status, request->rq_xid,
269                rqbd->rqbd_srv_ni->sni_ni->pni_name, event->initiator.nid,
270                request->rq_reqmsg->opc);
271
272         rc = svc->srv_handler(request);
273         CDEBUG(D_RPCTRACE, "Handled RPC pname:cluuid+ref:pid:xid:ni:nid:opc "
274                "%s:%s+%d:%d:"LPU64":%s:"LPX64":%d\n", current->comm,
275                (request->rq_export ?
276                 (char *)request->rq_export->exp_client_uuid.uuid : "0"),
277                (request->rq_export ?
278                 atomic_read(&request->rq_export->exp_refcount) : -99),
279                request->rq_reqmsg->status, request->rq_xid,
280                rqbd->rqbd_srv_ni->sni_ni->pni_name, event->initiator.nid,
281                request->rq_reqmsg->opc);
282
283 put_conn:
284         ptlrpc_put_connection(request->rq_connection);
285         if (request->rq_export != NULL)
286                 class_export_put(request->rq_export);
287
288  out:
289         if (atomic_dec_and_test (&rqbd->rqbd_refcount)) /* last reference? */
290                 ptlrpc_link_svc_me (rqbd);
291
292         return rc;
293 }
294
295 /* Don't use daemonize, it removes fs struct from new thread (bug 418) */
296 void ptlrpc_daemonize(void)
297 {
298         exit_mm(current);
299         lustre_daemonize_helper();
300         exit_files(current);
301         reparent_to_init();
302 }
303
304 static long timeval_sub(struct timeval *large, struct timeval *small)
305 {
306         return (large->tv_sec - small->tv_sec) * 1000000 +
307                 (large->tv_usec - small->tv_usec);
308 }
309
310 static int ptlrpc_main(void *arg)
311 {
312         struct ptlrpc_svc_data *data = arg;
313         struct obd_device *obddev = data->dev;
314         struct ptlrpc_service *svc = data->svc;
315         struct ptlrpc_thread *thread = data->thread;
316         struct ptlrpc_request *request;
317         ptl_event_t *event;
318         unsigned long flags;
319         struct timeval start_time, finish_time;
320         long total;
321         int rc = 0;
322         ENTRY;
323
324         lock_kernel();
325         ptlrpc_daemonize();
326
327         SIGNAL_MASK_LOCK(current, flags);
328         sigfillset(&current->blocked);
329         RECALC_SIGPENDING;
330         SIGNAL_MASK_UNLOCK(current, flags);
331
332         THREAD_NAME(current->comm, "%s", data->name);
333         unlock_kernel();
334
335         OBD_ALLOC(event, sizeof(*event));
336         if (event == NULL)
337                 GOTO(out, rc = -ENOMEM);
338         OBD_ALLOC(request, sizeof(*request));
339         if (request == NULL)
340                 GOTO(out_event, rc = -ENOMEM);
341
342         /* Record that the thread is running */
343         thread->t_flags = SVC_RUNNING;
344         wake_up(&thread->t_ctl_waitq);
345
346         /* XXX maintain a list of all managed devices: insert here */
347
348         do_gettimeofday(&finish_time);
349         /* And now, loop forever on requests */
350         while (1) {
351                 struct l_wait_info lwi = { 0 };
352                 l_wait_event_exclusive(svc->srv_waitq,
353                                        ptlrpc_check_event(svc, thread, event),
354                                        &lwi);
355
356                 spin_lock(&svc->srv_lock);
357                 if (thread->t_flags & SVC_STOPPING) {
358                         thread->t_flags &= ~SVC_STOPPING;
359                         spin_unlock(&svc->srv_lock);
360
361                         EXIT;
362                         break;
363                 }
364
365                 if (!(thread->t_flags & SVC_EVENT)) {
366                         CERROR("unknown flag in service");
367                         spin_unlock(&svc->srv_lock);
368                         LBUG();
369                         EXIT;
370                         break;
371                 }
372
373                 thread->t_flags &= ~SVC_EVENT;
374                 spin_unlock(&svc->srv_lock);
375
376                 do_gettimeofday(&start_time);
377                 total = timeval_sub(&start_time, &event->arrival_time);
378                 if (svc->svc_stats != NULL) {
379                         lprocfs_counter_add(svc->svc_stats, PTLRPC_REQWAIT_CNTR,
380                                             total);
381                         lprocfs_counter_add(svc->svc_stats,
382                                             PTLRPC_SVCIDLETIME_CNTR,
383                                             timeval_sub(&start_time,
384                                                         &finish_time));
385 #if 0 /* Wait for b_eq branch */
386                         lprocfs_counter_add(svc->svc_stats,
387                                             PTLRPC_SVCEQDEPTH_CNTR, 0);
388 #endif
389                 }
390
391                 if (total / 1000000 > (long)obd_timeout) {
392                         CERROR("Dropping request from NID "LPX64" because it's "
393                                "%ld seconds old.\n", event->initiator.nid,
394                                total / 1000000); /* bug 1502 */
395                 } else {
396                         CDEBUG(D_HA, "request from NID "LPX64" noticed after "
397                                "%ldus\n", event->initiator.nid, total);
398                         rc = handle_incoming_request(obddev, svc, event,
399                                                      request);
400                 }
401                 do_gettimeofday(&finish_time);
402                 total = timeval_sub(&finish_time, &start_time);
403
404                 CDEBUG((total / 1000000 > (long)obd_timeout) ? D_ERROR : D_HA,
405                        "request "LPU64" from NID "LPX64" processed in %ldus "
406                        "(%ldus total)\n", request->rq_xid, event->initiator.nid,
407                        total, timeval_sub(&finish_time, &event->arrival_time));
408
409                 if (svc->svc_stats != NULL) {
410                         int opc = opcode_offset(request->rq_reqmsg->opc);
411                         if (opc > 0) {
412                                 LASSERT(opc < LUSTRE_MAX_OPCODES);
413                                 lprocfs_counter_add(svc->svc_stats,
414                                                     opc + PTLRPC_LAST_CNTR,
415                                                     total);
416                         }
417                 }
418         }
419
420         /* NB should wait for all SENT callbacks to complete before exiting
421          * here.  Unfortunately at this time there is no way to track this
422          * state. */
423         OBD_FREE(request, sizeof(*request));
424 out_event:
425         OBD_FREE(event, sizeof(*event));
426 out:
427         thread->t_flags = SVC_STOPPED;
428         wake_up(&thread->t_ctl_waitq);
429
430         CDEBUG(D_NET, "service thread exiting, process %d: rc = %d\n",
431                current->pid, rc);
432         return rc;
433 }
434
435 static void ptlrpc_stop_thread(struct ptlrpc_service *svc,
436                                struct ptlrpc_thread *thread)
437 {
438         struct l_wait_info lwi = { 0 };
439
440         spin_lock(&svc->srv_lock);
441         thread->t_flags = SVC_STOPPING;
442         spin_unlock(&svc->srv_lock);
443
444         wake_up_all(&svc->srv_waitq);
445         l_wait_event(thread->t_ctl_waitq, (thread->t_flags & SVC_STOPPED),
446                      &lwi);
447 }
448
449 void ptlrpc_stop_all_threads(struct ptlrpc_service *svc)
450 {
451         spin_lock(&svc->srv_lock);
452         while (!list_empty(&svc->srv_threads)) {
453                 struct ptlrpc_thread *thread;
454                 thread = list_entry(svc->srv_threads.next, struct ptlrpc_thread,
455                                     t_link);
456                 spin_unlock(&svc->srv_lock);
457                 ptlrpc_stop_thread(svc, thread);
458                 spin_lock(&svc->srv_lock);
459                 list_del(&thread->t_link);
460                 OBD_FREE(thread, sizeof(*thread));
461         }
462         spin_unlock(&svc->srv_lock);
463 }
464
465 int ptlrpc_start_n_threads(struct obd_device *dev, struct ptlrpc_service *svc,
466                            int num_threads, char *base_name)
467 {
468         int i, rc = 0;
469         ENTRY;
470
471         for (i = 0; i < num_threads; i++) {
472                 char name[32];
473                 sprintf(name, "%s_%02d", base_name, i);
474                 rc = ptlrpc_start_thread(dev, svc, name);
475                 if (rc) {
476                         CERROR("cannot start %s thread #%d: rc %d\n", base_name,
477                                i, rc);
478                         ptlrpc_stop_all_threads(svc);
479                 }
480         }
481         RETURN(rc);
482 }
483
484 int ptlrpc_start_thread(struct obd_device *dev, struct ptlrpc_service *svc,
485                         char *name)
486 {
487         struct l_wait_info lwi = { 0 };
488         struct ptlrpc_svc_data d;
489         struct ptlrpc_thread *thread;
490         int rc;
491         ENTRY;
492
493         OBD_ALLOC(thread, sizeof(*thread));
494         if (thread == NULL)
495                 RETURN(-ENOMEM);
496         init_waitqueue_head(&thread->t_ctl_waitq);
497
498         d.dev = dev;
499         d.svc = svc;
500         d.name = name;
501         d.thread = thread;
502
503         spin_lock(&svc->srv_lock);
504         list_add(&thread->t_link, &svc->srv_threads);
505         spin_unlock(&svc->srv_lock);
506
507         /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
508          * just drop the VM and FILES in ptlrpc_daemonize() right away.
509          */
510         rc = kernel_thread(ptlrpc_main, &d, CLONE_VM | CLONE_FILES);
511         if (rc < 0) {
512                 CERROR("cannot start thread: %d\n", rc);
513                 OBD_FREE(thread, sizeof(*thread));
514                 RETURN(rc);
515         }
516         l_wait_event(thread->t_ctl_waitq, thread->t_flags & SVC_RUNNING, &lwi);
517
518         RETURN(0);
519 }
520
521 int ptlrpc_unregister_service(struct ptlrpc_service *service)
522 {
523         int i, rc;
524         struct ptlrpc_srv_ni *srv_ni;
525
526         LASSERT (list_empty (&service->srv_threads));
527
528         /* XXX We could reply (with failure) to all buffered requests
529          * _after_ unlinking _all_ the request buffers, but _before_
530          * freeing them.
531          */
532
533         for (i = 0; i < ptlrpc_ninterfaces; i++) {
534                 srv_ni = &service->srv_interfaces[i];
535                 CDEBUG (D_NET, "%s: tearing down interface %s\n",
536                         service->srv_name, srv_ni->sni_ni->pni_name);
537
538                 while (!list_empty (&srv_ni->sni_rqbds)) {
539                         struct ptlrpc_request_buffer_desc *rqbd =
540                                 list_entry (srv_ni->sni_rqbds.next,
541                                             struct ptlrpc_request_buffer_desc,
542                                             rqbd_list);
543
544                         list_del (&rqbd->rqbd_list);
545
546                         LASSERT (atomic_read (&rqbd->rqbd_refcount) > 0);
547                         /* refcount could be anything; it's possible for
548                          * the buffers to continued to get filled after all
549                          * the server threads exited.  But we know they
550                          * _have_ exited.
551                          */
552
553                         (void) PtlMEUnlink(rqbd->rqbd_me_h);
554                         /* The callback handler could have unlinked this ME
555                          * already (we're racing with her) but it's safe to
556                          * ensure it _has_ been unlinked.
557                          */
558
559                         OBD_FREE (rqbd->rqbd_buffer, service->srv_buf_size);
560                         OBD_FREE (rqbd, sizeof (*rqbd));
561                         srv_ni->sni_nrqbds--;
562                 }
563
564                 LASSERT (srv_ni->sni_nrqbds == 0);
565
566                 if (!PtlHandleEqual (srv_ni->sni_eq_h, PTL_HANDLE_NONE)) {
567                         rc = PtlEQFree(srv_ni->sni_eq_h);
568                         if (rc)
569                                 CERROR("%s.%d: PtlEQFree failed on %s: %d\n",
570                                        service->srv_name, i,
571                                        srv_ni->sni_ni->pni_name, rc);
572                 }
573         }
574
575         ptlrpc_lprocfs_unregister_service(service);
576
577         OBD_FREE(service,
578                  offsetof (struct ptlrpc_service,
579                            srv_interfaces[ptlrpc_ninterfaces]));
580         return 0;
581 }