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;
  41         int idx;
  42         int rc;
  43         ENTRY;
  44
  45         spin_lock(&svc->srv_lock);
  46
  47         if (thread->t_flags & SVC_STOPPING)
  48                 GOTO(out, rc = 1);
  49
  50         LASSERT ((thread->t_flags & SVC_EVENT) == 0);
  51         LASSERT (ptlrpc_ninterfaces > 0);
  52
  53         for (i = 0; i < ptlrpc_ninterfaces; i++) {
  54                 idx = (svc->srv_interface_rover + i) % ptlrpc_ninterfaces;
  55                 srv_ni = &svc->srv_interfaces[idx];
  56
  57                 LASSERT (!PtlHandleEqual (srv_ni->sni_eq_h, PTL_HANDLE_NONE));
  58
  59                 rc = PtlEQGet(srv_ni->sni_eq_h, event);
  60                 switch (rc) {
  61                 case PTL_OK:
  62                         /* next time start with the next interface */
  63                         svc->srv_interface_rover = (idx+1) % ptlrpc_ninterfaces;
  64                         thread->t_flags |= SVC_EVENT;
  65                         GOTO(out, rc = 1);
  66
  67                 case PTL_EQ_EMPTY:
  68                         continue;
  69
  70                 default:
  71                         CERROR("BUG: PtlEQGet returned %d\n", rc);
  72                         LBUG();
  73                 }
  74         }
  75         rc = 0;
  76         EXIT;
  77  out:
  78         spin_unlock(&svc->srv_lock);
  79         return rc;
  80 }
  81
  82 struct ptlrpc_service * ptlrpc_init_svc(__u32 nevents, __u32 nbufs,
  83                                         __u32 bufsize, __u32 max_req_size,
  84                                         int req_portal, int rep_portal,
  85                                         svc_handler_t handler, char *name,
  86                                         struct obd_device *obddev)
  87 {
  88         int i, j, ssize, rc;
  89         struct ptlrpc_service *service;
  90         struct ptlrpc_srv_ni  *srv_ni;
  91         ENTRY;
  92
  93         LASSERT (ptlrpc_ninterfaces > 0);
  94
  95         ssize = offsetof (struct ptlrpc_service,
  96                           srv_interfaces[ptlrpc_ninterfaces]);
  97         OBD_ALLOC(service, ssize);
  98         if (service == NULL)
  99                 RETURN(NULL);
 100
 101         service->srv_name = name;
 102         spin_lock_init(&service->srv_lock);
 103         INIT_LIST_HEAD(&service->srv_threads);
 104         init_waitqueue_head(&service->srv_waitq);
 105
 106         service->srv_max_req_size = max_req_size;
 107         service->srv_buf_size = bufsize;
 108
 109         service->srv_rep_portal = rep_portal;
 110         service->srv_req_portal = req_portal;
 111         service->srv_handler = handler;
 112         service->srv_interface_rover = 0;
 113
 114         /* First initialise enough for early teardown */
 115         for (i = 0; i < ptlrpc_ninterfaces; i++) {
 116                 srv_ni = &service->srv_interfaces[i];
 117
 118                 srv_ni->sni_service = service;
 119                 srv_ni->sni_ni = &ptlrpc_interfaces[i];
 120                 srv_ni->sni_eq_h = PTL_HANDLE_NONE;
 121                 INIT_LIST_HEAD(&srv_ni->sni_rqbds);
 122                 srv_ni->sni_nrqbds = 0;
 123                 atomic_set(&srv_ni->sni_nrqbds_receiving, 0);
 124         }
 125
 126         /* Now allocate the event queue and request buffers, assuming all
 127          * interfaces require the same level of buffering. */
 128         for (i = 0; i < ptlrpc_ninterfaces; i++) {
 129                 srv_ni = &service->srv_interfaces[i];
 130                 CDEBUG (D_NET, "%s: initialising interface %s\n", name,
 131                         srv_ni->sni_ni->pni_name);
 132
 133                 rc = PtlEQAlloc(srv_ni->sni_ni->pni_ni_h, nevents,
 134                                 request_in_callback, &(srv_ni->sni_eq_h));
 135                 if (rc != PTL_OK) {
 136                         CERROR("%s.%d: PtlEQAlloc on %s failed: %d\n",
 137                                name, i, srv_ni->sni_ni->pni_name, rc);
 138                         GOTO (failed, NULL);
 139                 }
 140
 141                 for (j = 0; j < nbufs; j++) {
 142                         struct ptlrpc_request_buffer_desc *rqbd;
 143
 144                         OBD_ALLOC(rqbd, sizeof(*rqbd));
 145                         if (rqbd == NULL) {
 146                                 CERROR ("%s.%d: Can't allocate request "
 147                                         "descriptor %d on %s\n",
 148                                         name, i, srv_ni->sni_nrqbds,
 149                                         srv_ni->sni_ni->pni_name);
 150                                 GOTO(failed, NULL);
 151                         }
 152
 153                         rqbd->rqbd_srv_ni = srv_ni;
 154                         rqbd->rqbd_me_h = PTL_HANDLE_NONE;
 155                         atomic_set(&rqbd->rqbd_refcount, 0);
 156
 157                         OBD_ALLOC(rqbd->rqbd_buffer, service->srv_buf_size);
 158                         if (rqbd->rqbd_buffer == NULL) {
 159                                 CERROR ("%s.%d: Can't allocate request "
 160                                         "buffer %d on %s\n",
 161                                         name, i, srv_ni->sni_nrqbds,
 162                                         srv_ni->sni_ni->pni_name);
 163                                 OBD_FREE(rqbd, sizeof(*rqbd));
 164                                 GOTO(failed, NULL);
 165                         }
 166                         list_add(&rqbd->rqbd_list, &srv_ni->sni_rqbds);
 167                         srv_ni->sni_nrqbds++;
 168
 169                         ptlrpc_link_svc_me(rqbd);
 170                 }
 171         }
 172
 173         ptlrpc_lprocfs_register_service(obddev, service);
 174
 175         CDEBUG(D_NET, "%s: Started on %d interfaces, listening on portal %d\n",
 176                service->srv_name, ptlrpc_ninterfaces, service->srv_req_portal);
 177
 178         RETURN(service);
 179 failed:
 180         ptlrpc_unregister_service(service);
 181         return NULL;
 182 }
 183
 184 static int handle_incoming_request(struct obd_device *obddev,
 185                                    struct ptlrpc_service *svc,
 186                                    ptl_event_t *event,
 187                                    struct ptlrpc_request *request)
 188 {
 189         struct ptlrpc_request_buffer_desc *rqbd = event->mem_desc.user_ptr;
 190         int rc;
 191
 192         /* FIXME: If we move to an event-driven model, we should put the request
 193          * on the stack of mds_handle instead. */
 194
 195         LASSERT (atomic_read (&rqbd->rqbd_refcount) > 0);
 196         LASSERT ((event->mem_desc.options & (PTL_MD_IOV | PTL_MD_KIOV)) == 0);
 197         LASSERT (rqbd->rqbd_srv_ni->sni_service == svc);
 198         LASSERT (rqbd->rqbd_buffer == event->mem_desc.start);
 199         LASSERT (event->offset + event->mlength <= svc->srv_buf_size);
 200
 201         memset(request, 0, sizeof(*request));
 202         spin_lock_init (&request->rq_lock);
 203         INIT_LIST_HEAD(&request->rq_list);
 204         request->rq_svc = svc;
 205         request->rq_obd = obddev;
 206         request->rq_xid = event->match_bits;
 207         request->rq_reqmsg = event->mem_desc.start + event->offset;
 208         request->rq_reqlen = event->mlength;
 209
 210 #if SWAB_PARANOIA
 211         /* Clear request swab mask; this is a new request */
 212         request->rq_req_swab_mask = 0;
 213 #endif
 214         rc = lustre_unpack_msg (request->rq_reqmsg, request->rq_reqlen);
 215         if (rc != 0) {
 216                 CERROR ("error unpacking request: ptl %d from "LPX64
 217                         " xid "LPU64"\n", svc->srv_req_portal,
 218                        event->initiator.nid, request->rq_xid);
 219                 goto out;
 220         }
 221         rc = -EINVAL;
 222         if (request->rq_reqmsg->type != PTL_RPC_MSG_REQUEST) {
 223                 CERROR("wrong packet type received (type=%u)\n",
 224                        request->rq_reqmsg->type);
 225                 goto out;
 226         }
 227
 228         CDEBUG(D_NET, "got req "LPD64" (md: %p + %d)\n", request->rq_xid,
 229                event->mem_desc.start, event->offset);
 230
 231         request->rq_peer.peer_nid = event->initiator.nid;
 232         request->rq_peer.peer_ni = rqbd->rqbd_srv_ni->sni_ni;
 233
 234         request->rq_export = class_conn2export(&request->rq_reqmsg->handle);
 235
 236         if (request->rq_export) {
 237                 request->rq_connection = request->rq_export->exp_connection;
 238                 ptlrpc_connection_addref(request->rq_connection);
 239                 request->rq_export->exp_last_request_time =
 240                         LTIME_S(CURRENT_TIME);
 241         } else {
 242                 /* create a (hopefully temporary) connection that will be used
 243                  * to send the reply if this call doesn't create an export.
 244                  * XXX revisit this when we revamp ptlrpc */
 245                 request->rq_connection =
 246                         ptlrpc_get_connection(&request->rq_peer, NULL);
 247         }
 248
 249         CDEBUG(D_RPCTRACE, "Handling RPC pname:cluuid:pid:xid:ni:nid:opc %s:%s:%d:"
 250                LPU64":%s:"LPX64":%d\n",
 251                current->comm,
 252                (request->rq_export ?
 253                 (char *)request->rq_export->exp_client_uuid.uuid : "0"),
 254                request->rq_reqmsg->status, request->rq_xid,
 255                rqbd->rqbd_srv_ni->sni_ni->pni_name, event->initiator.nid,
 256                request->rq_reqmsg->opc);
 257
 258         rc = svc->srv_handler(request);
 259         CDEBUG(D_RPCTRACE, "Handled RPC pname:cluuid:pid:xid:ni:nid:opc %s:%s:%d:"
 260                LPU64":%s:"LPX64":%d\n",
 261                current->comm,
 262                (request->rq_export ?
 263                 (char *)request->rq_export->exp_client_uuid.uuid : "0"),
 264                request->rq_reqmsg->status, request->rq_xid,
 265                rqbd->rqbd_srv_ni->sni_ni->pni_name, event->initiator.nid,
 266                request->rq_reqmsg->opc);
 267
 268         ptlrpc_put_connection(request->rq_connection);
 269         if (request->rq_export != NULL)
 270                 class_export_put(request->rq_export);
 271
 272  out:
 273         if (atomic_dec_and_test (&rqbd->rqbd_refcount)) /* last reference? */
 274                 ptlrpc_link_svc_me (rqbd);
 275
 276         return rc;
 277 }
 278
 279 /* Don't use daemonize, it removes fs struct from new thread (bug 418) */
 280 void ptlrpc_daemonize(void)
 281 {
 282         exit_mm(current);
 283
 284         current->session = 1;
 285         current->pgrp = 1;
 286         current->tty = NULL;
 287
 288         exit_files(current);
 289         reparent_to_init();
 290 }
 291
 292 static int ptlrpc_main(void *arg)
 293 {
 294         struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
 295         struct obd_device *obddev = data->dev;
 296         struct ptlrpc_service *svc = data->svc;
 297         struct ptlrpc_thread *thread = data->thread;
 298         struct ptlrpc_request *request;
 299         ptl_event_t *event;
 300         int rc = 0;
 301         unsigned long flags;
 302         cycles_t workdone_time = -1;
 303         cycles_t svc_workcycles = -1;
 304         ENTRY;
 305
 306         lock_kernel();
 307         ptlrpc_daemonize();
 308
 309         SIGNAL_MASK_LOCK(current, flags);
 310         sigfillset(&current->blocked);
 311         RECALC_SIGPENDING;
 312         SIGNAL_MASK_UNLOCK(current, flags);
 313
 314 #if defined(__arch_um__) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,4,20))
 315         sprintf(current->comm, "%s|%d", data->name,current->thread.extern_pid);
 316 #elif defined(__arch_um__) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
 317         sprintf(current->comm, "%s|%d", data->name,
 318                 current->thread.mode.tt.extern_pid);
 319 #else
 320         strcpy(current->comm, data->name);
 321 #endif
 322         unlock_kernel();
 323
 324         OBD_ALLOC(event, sizeof(*event));
 325         if (!event)
 326                 GOTO(out, rc = -ENOMEM);
 327         OBD_ALLOC(request, sizeof(*request));
 328         if (!request)
 329                 GOTO(out_event, rc = -ENOMEM);
 330
 331         /* Record that the thread is running */
 332         thread->t_flags = SVC_RUNNING;
 333         wake_up(&thread->t_ctl_waitq);
 334
 335         /* XXX maintain a list of all managed devices: insert here */
 336
 337         /* And now, loop forever on requests */
 338         while (1) {
 339                 struct l_wait_info lwi = { 0 };
 340                 l_wait_event(svc->srv_waitq,
 341                              ptlrpc_check_event(svc, thread, event), &lwi);
 342
 343                 if (thread->t_flags & SVC_STOPPING) {
 344                         spin_lock(&svc->srv_lock);
 345                         thread->t_flags &= ~SVC_STOPPING;
 346                         spin_unlock(&svc->srv_lock);
 347
 348                         EXIT;
 349                         break;
 350                 }
 351
 352                 if (thread->t_flags & SVC_EVENT) {
 353                         cycles_t  workstart_time;
 354
 355                         spin_lock(&svc->srv_lock);
 356                         thread->t_flags &= ~SVC_EVENT;
 357                         /* Update Service Statistics */
 358                         workstart_time = get_cycles();
 359                         if (workdone_time != -1 && svc->svc_stats != NULL) {
 360                                 /* Stats for req(n) are updated just before
 361                                  * req(n+1) is executed. This avoids need to
 362                                  * reacquire svc->srv_lock after
 363                                  * call to handling_request().
 364                                  */
 365                                 int opc;
 366
 367                                 /* req_waittime */
 368                                 lprocfs_counter_add(svc->svc_stats,
 369                                                     PTLRPC_REQWAIT_CNTR,
 370                                                     (workstart_time -
 371                                                      event->arrival_time));
 372                                 /* svc_eqdepth */
 373                                 /* Wait for b_eq branch
 374                                 lprocfs_counter_add(svc->svc_stats,
 375                                                     PTLRPC_SVCEQDEPTH_CNTR,
 376                                                     0);
 377                                 */
 378                                 /* svc_idletime */
 379                                 lprocfs_counter_add(svc->svc_stats,
 380                                                     PTLRPC_SVCIDLETIME_CNTR,
 381                                                     (workstart_time -
 382                                                      workdone_time));
 383                                 /* previous request */
 384                                 opc = opcode_offset(request->rq_reqmsg->opc);
 385                                 if (opc > 0) {
 386                                         LASSERT(opc < LUSTRE_MAX_OPCODES);
 387                                         lprocfs_counter_add(svc->svc_stats, opc,
 388                                                             PTLRPC_LAST_CNTR +
 389                                                             svc_workcycles);
 390                                 }
 391                         }
 392                         spin_unlock(&svc->srv_lock);
 393
 394                         rc = handle_incoming_request(obddev, svc, event,
 395                                                      request);
 396                         workdone_time = get_cycles();
 397                         svc_workcycles = workdone_time - workstart_time;
 398                         continue;
 399                 }
 400
 401                 CERROR("unknown break in service");
 402                 LBUG();
 403                 EXIT;
 404                 break;
 405         }
 406
 407         /* NB should wait for all SENT callbacks to complete before exiting
 408          * here.  Unfortunately at this time there is no way to track this
 409          * state.
 410          */
 411         OBD_FREE(request, sizeof(*request));
 412 out_event:
 413         OBD_FREE(event, sizeof(*event));
 414 out:
 415         thread->t_flags = SVC_STOPPED;
 416         wake_up(&thread->t_ctl_waitq);
 417
 418         CDEBUG(D_NET, "service thread exiting, process %d: rc = %d\n",
 419                current->pid, rc);
 420         return rc;
 421 }
 422
 423 static void ptlrpc_stop_thread(struct ptlrpc_service *svc,
 424                                struct ptlrpc_thread *thread)
 425 {
 426         struct l_wait_info lwi = { 0 };
 427
 428         spin_lock(&svc->srv_lock);
 429         thread->t_flags = SVC_STOPPING;
 430         spin_unlock(&svc->srv_lock);
 431
 432         wake_up(&svc->srv_waitq);
 433         l_wait_event(thread->t_ctl_waitq, (thread->t_flags & SVC_STOPPED),
 434                      &lwi);
 435 }
 436
 437 void ptlrpc_stop_all_threads(struct ptlrpc_service *svc)
 438 {
 439         spin_lock(&svc->srv_lock);
 440         while (!list_empty(&svc->srv_threads)) {
 441                 struct ptlrpc_thread *thread;
 442                 thread = list_entry(svc->srv_threads.next, struct ptlrpc_thread,
 443                                     t_link);
 444                 spin_unlock(&svc->srv_lock);
 445                 ptlrpc_stop_thread(svc, thread);
 446                 spin_lock(&svc->srv_lock);
 447                 list_del(&thread->t_link);
 448                 OBD_FREE(thread, sizeof(*thread));
 449         }
 450         spin_unlock(&svc->srv_lock);
 451 }
 452
 453 int ptlrpc_start_thread(struct obd_device *dev, struct ptlrpc_service *svc,
 454                         char *name)
 455 {
 456         struct l_wait_info lwi = { 0 };
 457         struct ptlrpc_svc_data d;
 458         struct ptlrpc_thread *thread;
 459         int rc;
 460         ENTRY;
 461
 462         OBD_ALLOC(thread, sizeof(*thread));
 463         if (thread == NULL)
 464                 RETURN(-ENOMEM);
 465         init_waitqueue_head(&thread->t_ctl_waitq);
 466
 467         d.dev = dev;
 468         d.svc = svc;
 469         d.name = name;
 470         d.thread = thread;
 471
 472         spin_lock(&svc->srv_lock);
 473         list_add(&thread->t_link, &svc->srv_threads);
 474         spin_unlock(&svc->srv_lock);
 475
 476         /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
 477          * just drop the VM and FILES in ptlrpc_daemonize() right away.
 478          */
 479         rc = kernel_thread(ptlrpc_main, &d, CLONE_VM | CLONE_FILES);
 480         if (rc < 0) {
 481                 CERROR("cannot start thread: %d\n", rc);
 482                 OBD_FREE(thread, sizeof(*thread));
 483                 RETURN(rc);
 484         }
 485         l_wait_event(thread->t_ctl_waitq, thread->t_flags & SVC_RUNNING, &lwi);
 486
 487         RETURN(0);
 488 }
 489
 490 int ptlrpc_unregister_service(struct ptlrpc_service *service)
 491 {
 492         int i, rc;
 493         struct ptlrpc_srv_ni *srv_ni;
 494
 495         LASSERT (list_empty (&service->srv_threads));
 496
 497         /* XXX We could reply (with failure) to all buffered requests
 498          * _after_ unlinking _all_ the request buffers, but _before_
 499          * freeing them.
 500          */
 501
 502         for (i = 0; i < ptlrpc_ninterfaces; i++) {
 503                 srv_ni = &service->srv_interfaces[i];
 504                 CDEBUG (D_NET, "%s: tearing down interface %s\n",
 505                         service->srv_name, srv_ni->sni_ni->pni_name);
 506
 507                 while (!list_empty (&srv_ni->sni_rqbds)) {
 508                         struct ptlrpc_request_buffer_desc *rqbd =
 509                                 list_entry (srv_ni->sni_rqbds.next,
 510                                             struct ptlrpc_request_buffer_desc,
 511                                             rqbd_list);
 512
 513                         list_del (&rqbd->rqbd_list);
 514
 515                         LASSERT (atomic_read (&rqbd->rqbd_refcount) > 0);
 516                         /* refcount could be anything; it's possible for
 517                          * the buffers to continued to get filled after all
 518                          * the server threads exited.  But we know they
 519                          * _have_ exited.
 520                          */
 521
 522                         (void) PtlMEUnlink(rqbd->rqbd_me_h);
 523                         /* The callback handler could have unlinked this ME
 524                          * already (we're racing with her) but it's safe to
 525                          * ensure it _has_ been unlinked.
 526                          */
 527
 528                         OBD_FREE (rqbd->rqbd_buffer, service->srv_buf_size);
 529                         OBD_FREE (rqbd, sizeof (*rqbd));
 530                         srv_ni->sni_nrqbds--;
 531                 }
 532
 533                 LASSERT (srv_ni->sni_nrqbds == 0);
 534
 535                 if (!PtlHandleEqual (srv_ni->sni_eq_h, PTL_HANDLE_NONE)) {
 536                         rc = PtlEQFree(srv_ni->sni_eq_h);
 537                         if (rc)
 538                                 CERROR("%s.%d: PtlEQFree failed on %s: %d\n",
 539                                        service->srv_name, i,
 540                                        srv_ni->sni_ni->pni_name, rc);
 541                 }
 542         }
 543
 544         ptlrpc_lprocfs_unregister_service(service);
 545
 546         OBD_FREE(service,
 547                  offsetof (struct ptlrpc_service,
 548                            srv_interfaces[ptlrpc_ninterfaces]));
 549         return 0;
 550 }