drivers/infiniband/hw/ehca/ehca_irq.c

   1 /*
   2  *  IBM eServer eHCA Infiniband device driver for Linux on POWER
   3  *
   4  *  Functions for EQs, NEQs and interrupts
   5  *
   6  *  Authors: Heiko J Schick <schickhj@de.ibm.com>
   7  *           Khadija Souissi <souissi@de.ibm.com>
   8  *           Hoang-Nam Nguyen <hnguyen@de.ibm.com>
   9  *           Joachim Fenkes <fenkes@de.ibm.com>
  10  *
  11  *  Copyright (c) 2005 IBM Corporation
  12  *
  13  *  All rights reserved.
  14  *
  15  *  This source code is distributed under a dual license of GPL v2.0 and OpenIB
  16  *  BSD.
  17  *
  18  * OpenIB BSD License
  19  *
  20  * Redistribution and use in source and binary forms, with or without
  21  * modification, are permitted provided that the following conditions are met:
  22  *
  23  * Redistributions of source code must retain the above copyright notice, this
  24  * list of conditions and the following disclaimer.
  25  *
  26  * Redistributions in binary form must reproduce the above copyright notice,
  27  * this list of conditions and the following disclaimer in the documentation
  28  * and/or other materials
  29  * provided with the distribution.
  30  *
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  32  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  34  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  35  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  36  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  37  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  38  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  39  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  40  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGE.
  42  */
  43
  44 #include <linux/slab.h>
  45
  46 #include "ehca_classes.h"
  47 #include "ehca_irq.h"
  48 #include "ehca_iverbs.h"
  49 #include "ehca_tools.h"
  50 #include "hcp_if.h"
  51 #include "hipz_fns.h"
  52 #include "ipz_pt_fn.h"
  53
  54 #define EQE_COMPLETION_EVENT   EHCA_BMASK_IBM( 1,  1)
  55 #define EQE_CQ_QP_NUMBER       EHCA_BMASK_IBM( 8, 31)
  56 #define EQE_EE_IDENTIFIER      EHCA_BMASK_IBM( 2,  7)
  57 #define EQE_CQ_NUMBER          EHCA_BMASK_IBM( 8, 31)
  58 #define EQE_QP_NUMBER          EHCA_BMASK_IBM( 8, 31)
  59 #define EQE_QP_TOKEN           EHCA_BMASK_IBM(32, 63)
  60 #define EQE_CQ_TOKEN           EHCA_BMASK_IBM(32, 63)
  61
  62 #define NEQE_COMPLETION_EVENT  EHCA_BMASK_IBM( 1,  1)
  63 #define NEQE_EVENT_CODE        EHCA_BMASK_IBM( 2,  7)
  64 #define NEQE_PORT_NUMBER       EHCA_BMASK_IBM( 8, 15)
  65 #define NEQE_PORT_AVAILABILITY EHCA_BMASK_IBM(16, 16)
  66 #define NEQE_DISRUPTIVE        EHCA_BMASK_IBM(16, 16)
  67 #define NEQE_SPECIFIC_EVENT    EHCA_BMASK_IBM(16, 23)
  68
  69 #define ERROR_DATA_LENGTH      EHCA_BMASK_IBM(52, 63)
  70 #define ERROR_DATA_TYPE        EHCA_BMASK_IBM( 0,  7)
  71
  72 static void queue_comp_task(struct ehca_cq *__cq);
  73
  74 static struct ehca_comp_pool *pool;
  75
  76 static inline void comp_event_callback(struct ehca_cq *cq)
  77 {
  78         if (!cq->ib_cq.comp_handler)
  79                 return;
  80
  81         spin_lock(&cq->cb_lock);
  82         cq->ib_cq.comp_handler(&cq->ib_cq, cq->ib_cq.cq_context);
  83         spin_unlock(&cq->cb_lock);
  84
  85         return;
  86 }
  87
  88 static void print_error_data(struct ehca_shca *shca, void *data,
  89                              u64 *rblock, int length)
  90 {
  91         u64 type = EHCA_BMASK_GET(ERROR_DATA_TYPE, rblock[2]);
  92         u64 resource = rblock[1];
  93
  94         switch (type) {
  95         case 0x1: /* Queue Pair */
  96         {
  97                 struct ehca_qp *qp = (struct ehca_qp *)data;
  98
  99                 /* only print error data if AER is set */
 100                 if (rblock[6] == 0)
 101                         return;
 102
 103                 ehca_err(&shca->ib_device,
 104                          "QP 0x%x (resource=%llx) has errors.",
 105                          qp->ib_qp.qp_num, resource);
 106                 break;
 107         }
 108         case 0x4: /* Completion Queue */
 109         {
 110                 struct ehca_cq *cq = (struct ehca_cq *)data;
 111
 112                 ehca_err(&shca->ib_device,
 113                          "CQ 0x%x (resource=%llx) has errors.",
 114                          cq->cq_number, resource);
 115                 break;
 116         }
 117         default:
 118                 ehca_err(&shca->ib_device,
 119                          "Unknown error type: %llx on %s.",
 120                          type, shca->ib_device.name);
 121                 break;
 122         }
 123
 124         ehca_err(&shca->ib_device, "Error data is available: %llx.", resource);
 125         ehca_err(&shca->ib_device, "EHCA ----- error data begin "
 126                  "---------------------------------------------------");
 127         ehca_dmp(rblock, length, "resource=%llx", resource);
 128         ehca_err(&shca->ib_device, "EHCA ----- error data end "
 129                  "----------------------------------------------------");
 130
 131         return;
 132 }
 133
 134 int ehca_error_data(struct ehca_shca *shca, void *data,
 135                     u64 resource)
 136 {
 137
 138         unsigned long ret;
 139         u64 *rblock;
 140         unsigned long block_count;
 141
 142         rblock = ehca_alloc_fw_ctrlblock(GFP_ATOMIC);
 143         if (!rblock) {
 144                 ehca_err(&shca->ib_device, "Cannot allocate rblock memory.");
 145                 ret = -ENOMEM;
 146                 goto error_data1;
 147         }
 148
 149         /* rblock must be 4K aligned and should be 4K large */
 150         ret = hipz_h_error_data(shca->ipz_hca_handle,
 151                                 resource,
 152                                 rblock,
 153                                 &block_count);
 154
 155         if (ret == H_R_STATE)
 156                 ehca_err(&shca->ib_device,
 157                          "No error data is available: %llx.", resource);
 158         else if (ret == H_SUCCESS) {
 159                 int length;
 160
 161                 length = EHCA_BMASK_GET(ERROR_DATA_LENGTH, rblock[0]);
 162
 163                 if (length > EHCA_PAGESIZE)
 164                         length = EHCA_PAGESIZE;
 165
 166                 print_error_data(shca, data, rblock, length);
 167         } else
 168                 ehca_err(&shca->ib_device,
 169                          "Error data could not be fetched: %llx", resource);
 170
 171         ehca_free_fw_ctrlblock(rblock);
 172
 173 error_data1:
 174         return ret;
 175
 176 }
 177
 178 static void dispatch_qp_event(struct ehca_shca *shca, struct ehca_qp *qp,
 179                               enum ib_event_type event_type)
 180 {
 181         struct ib_event event;
 182
 183         /* PATH_MIG without the QP ever having been armed is false alarm */
 184         if (event_type == IB_EVENT_PATH_MIG && !qp->mig_armed)
 185                 return;
 186
 187         event.device = &shca->ib_device;
 188         event.event = event_type;
 189
 190         if (qp->ext_type == EQPT_SRQ) {
 191                 if (!qp->ib_srq.event_handler)
 192                         return;
 193
 194                 event.element.srq = &qp->ib_srq;
 195                 qp->ib_srq.event_handler(&event, qp->ib_srq.srq_context);
 196         } else {
 197                 if (!qp->ib_qp.event_handler)
 198                         return;
 199
 200                 event.element.qp = &qp->ib_qp;
 201                 qp->ib_qp.event_handler(&event, qp->ib_qp.qp_context);
 202         }
 203 }
 204
 205 static void qp_event_callback(struct ehca_shca *shca, u64 eqe,
 206                               enum ib_event_type event_type, int fatal)
 207 {
 208         struct ehca_qp *qp;
 209         u32 token = EHCA_BMASK_GET(EQE_QP_TOKEN, eqe);
 210
 211         read_lock(&ehca_qp_idr_lock);
 212         qp = idr_find(&ehca_qp_idr, token);
 213         if (qp)
 214                 atomic_inc(&qp->nr_events);
 215         read_unlock(&ehca_qp_idr_lock);
 216
 217         if (!qp)
 218                 return;
 219
 220         if (fatal)
 221                 ehca_error_data(shca, qp, qp->ipz_qp_handle.handle);
 222
 223         dispatch_qp_event(shca, qp, fatal && qp->ext_type == EQPT_SRQ ?
 224                           IB_EVENT_SRQ_ERR : event_type);
 225
 226         /*
 227          * eHCA only processes one WQE at a time for SRQ base QPs,
 228          * so the last WQE has been processed as soon as the QP enters
 229          * error state.
 230          */
 231         if (fatal && qp->ext_type == EQPT_SRQBASE)
 232                 dispatch_qp_event(shca, qp, IB_EVENT_QP_LAST_WQE_REACHED);
 233
 234         if (atomic_dec_and_test(&qp->nr_events))
 235                 wake_up(&qp->wait_completion);
 236         return;
 237 }
 238
 239 static void cq_event_callback(struct ehca_shca *shca,
 240                               u64 eqe)
 241 {
 242         struct ehca_cq *cq;
 243         u32 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe);
 244
 245         read_lock(&ehca_cq_idr_lock);
 246         cq = idr_find(&ehca_cq_idr, token);
 247         if (cq)
 248                 atomic_inc(&cq->nr_events);
 249         read_unlock(&ehca_cq_idr_lock);
 250
 251         if (!cq)
 252                 return;
 253
 254         ehca_error_data(shca, cq, cq->ipz_cq_handle.handle);
 255
 256         if (atomic_dec_and_test(&cq->nr_events))
 257                 wake_up(&cq->wait_completion);
 258
 259         return;
 260 }
 261
 262 static void parse_identifier(struct ehca_shca *shca, u64 eqe)
 263 {
 264         u8 identifier = EHCA_BMASK_GET(EQE_EE_IDENTIFIER, eqe);
 265
 266         switch (identifier) {
 267         case 0x02: /* path migrated */
 268                 qp_event_callback(shca, eqe, IB_EVENT_PATH_MIG, 0);
 269                 break;
 270         case 0x03: /* communication established */
 271                 qp_event_callback(shca, eqe, IB_EVENT_COMM_EST, 0);
 272                 break;
 273         case 0x04: /* send queue drained */
 274                 qp_event_callback(shca, eqe, IB_EVENT_SQ_DRAINED, 0);
 275                 break;
 276         case 0x05: /* QP error */
 277         case 0x06: /* QP error */
 278                 qp_event_callback(shca, eqe, IB_EVENT_QP_FATAL, 1);
 279                 break;
 280         case 0x07: /* CQ error */
 281         case 0x08: /* CQ error */
 282                 cq_event_callback(shca, eqe);
 283                 break;
 284         case 0x09: /* MRMWPTE error */
 285                 ehca_err(&shca->ib_device, "MRMWPTE error.");
 286                 break;
 287         case 0x0A: /* port event */
 288                 ehca_err(&shca->ib_device, "Port event.");
 289                 break;
 290         case 0x0B: /* MR access error */
 291                 ehca_err(&shca->ib_device, "MR access error.");
 292                 break;
 293         case 0x0C: /* EQ error */
 294                 ehca_err(&shca->ib_device, "EQ error.");
 295                 break;
 296         case 0x0D: /* P/Q_Key mismatch */
 297                 ehca_err(&shca->ib_device, "P/Q_Key mismatch.");
 298                 break;
 299         case 0x10: /* sampling complete */
 300                 ehca_err(&shca->ib_device, "Sampling complete.");
 301                 break;
 302         case 0x11: /* unaffiliated access error */
 303                 ehca_err(&shca->ib_device, "Unaffiliated access error.");
 304                 break;
 305         case 0x12: /* path migrating */
 306                 ehca_err(&shca->ib_device, "Path migrating.");
 307                 break;
 308         case 0x13: /* interface trace stopped */
 309                 ehca_err(&shca->ib_device, "Interface trace stopped.");
 310                 break;
 311         case 0x14: /* first error capture info available */
 312                 ehca_info(&shca->ib_device, "First error capture available");
 313                 break;
 314         case 0x15: /* SRQ limit reached */
 315                 qp_event_callback(shca, eqe, IB_EVENT_SRQ_LIMIT_REACHED, 0);
 316                 break;
 317         default:
 318                 ehca_err(&shca->ib_device, "Unknown identifier: %x on %s.",
 319                          identifier, shca->ib_device.name);
 320                 break;
 321         }
 322
 323         return;
 324 }
 325
 326 static void dispatch_port_event(struct ehca_shca *shca, int port_num,
 327                                 enum ib_event_type type, const char *msg)
 328 {
 329         struct ib_event event;
 330
 331         ehca_info(&shca->ib_device, "port %d %s.", port_num, msg);
 332         event.device = &shca->ib_device;
 333         event.event = type;
 334         event.element.port_num = port_num;
 335         ib_dispatch_event(&event);
 336 }
 337
 338 static void notify_port_conf_change(struct ehca_shca *shca, int port_num)
 339 {
 340         struct ehca_sma_attr  new_attr;
 341         struct ehca_sma_attr *old_attr = &shca->sport[port_num - 1].saved_attr;
 342
 343         ehca_query_sma_attr(shca, port_num, &new_attr);
 344
 345         if (new_attr.sm_sl  != old_attr->sm_sl ||
 346             new_attr.sm_lid != old_attr->sm_lid)
 347                 dispatch_port_event(shca, port_num, IB_EVENT_SM_CHANGE,
 348                                     "SM changed");
 349
 350         if (new_attr.lid != old_attr->lid ||
 351             new_attr.lmc != old_attr->lmc)
 352                 dispatch_port_event(shca, port_num, IB_EVENT_LID_CHANGE,
 353                                     "LID changed");
 354
 355         if (new_attr.pkey_tbl_len != old_attr->pkey_tbl_len ||
 356             memcmp(new_attr.pkeys, old_attr->pkeys,
 357                    sizeof(u16) * new_attr.pkey_tbl_len))
 358                 dispatch_port_event(shca, port_num, IB_EVENT_PKEY_CHANGE,
 359                                     "P_Key changed");
 360
 361         *old_attr = new_attr;
 362 }
 363
 364 /* replay modify_qp for sqps -- return 0 if all is well, 1 if AQP1 destroyed */
 365 static int replay_modify_qp(struct ehca_sport *sport)
 366 {
 367         int aqp1_destroyed;
 368         unsigned long flags;
 369
 370         spin_lock_irqsave(&sport->mod_sqp_lock, flags);
 371
 372         aqp1_destroyed = !sport->ibqp_sqp[IB_QPT_GSI];
 373
 374         if (sport->ibqp_sqp[IB_QPT_SMI])
 375                 ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_SMI]);
 376         if (!aqp1_destroyed)
 377                 ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_GSI]);
 378
 379         spin_unlock_irqrestore(&sport->mod_sqp_lock, flags);
 380
 381         return aqp1_destroyed;
 382 }
 383
 384 static void parse_ec(struct ehca_shca *shca, u64 eqe)
 385 {
 386         u8 ec   = EHCA_BMASK_GET(NEQE_EVENT_CODE, eqe);
 387         u8 port = EHCA_BMASK_GET(NEQE_PORT_NUMBER, eqe);
 388         u8 spec_event;
 389         struct ehca_sport *sport = &shca->sport[port - 1];
 390
 391         switch (ec) {
 392         case 0x30: /* port availability change */
 393                 if (EHCA_BMASK_GET(NEQE_PORT_AVAILABILITY, eqe)) {
 394                         /* only replay modify_qp calls in autodetect mode;
 395                          * if AQP1 was destroyed, the port is already down
 396                          * again and we can drop the event.
 397                          */
 398                         if (ehca_nr_ports < 0)
 399                                 if (replay_modify_qp(sport))
 400                                         break;
 401
 402                         sport->port_state = IB_PORT_ACTIVE;
 403                         dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
 404                                             "is active");
 405                         ehca_query_sma_attr(shca, port, &sport->saved_attr);
 406                 } else {
 407                         sport->port_state = IB_PORT_DOWN;
 408                         dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
 409                                             "is inactive");
 410                 }
 411                 break;
 412         case 0x31:
 413                 /* port configuration change
 414                  * disruptive change is caused by
 415                  * LID, PKEY or SM change
 416                  */
 417                 if (EHCA_BMASK_GET(NEQE_DISRUPTIVE, eqe)) {
 418                         ehca_warn(&shca->ib_device, "disruptive port "
 419                                   "%d configuration change", port);
 420
 421                         sport->port_state = IB_PORT_DOWN;
 422                         dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
 423                                             "is inactive");
 424
 425                         sport->port_state = IB_PORT_ACTIVE;
 426                         dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
 427                                             "is active");
 428                         ehca_query_sma_attr(shca, port,
 429                                             &sport->saved_attr);
 430                 } else
 431                         notify_port_conf_change(shca, port);
 432                 break;
 433         case 0x32: /* adapter malfunction */
 434                 ehca_err(&shca->ib_device, "Adapter malfunction.");
 435                 break;
 436         case 0x33:  /* trace stopped */
 437                 ehca_err(&shca->ib_device, "Traced stopped.");
 438                 break;
 439         case 0x34: /* util async event */
 440                 spec_event = EHCA_BMASK_GET(NEQE_SPECIFIC_EVENT, eqe);
 441                 if (spec_event == 0x80) /* client reregister required */
 442                         dispatch_port_event(shca, port,
 443                                             IB_EVENT_CLIENT_REREGISTER,
 444                                             "client reregister req.");
 445                 else
 446                         ehca_warn(&shca->ib_device, "Unknown util async "
 447                                   "event %x on port %x", spec_event, port);
 448                 break;
 449         default:
 450                 ehca_err(&shca->ib_device, "Unknown event code: %x on %s.",
 451                          ec, shca->ib_device.name);
 452                 break;
 453         }
 454
 455         return;
 456 }
 457
 458 static inline void reset_eq_pending(struct ehca_cq *cq)
 459 {
 460         u64 CQx_EP;
 461         struct h_galpa gal = cq->galpas.kernel;
 462
 463         hipz_galpa_store_cq(gal, cqx_ep, 0x0);
 464         CQx_EP = hipz_galpa_load(gal, CQTEMM_OFFSET(cqx_ep));
 465
 466         return;
 467 }
 468
 469 irqreturn_t ehca_interrupt_neq(int irq, void *dev_id)
 470 {
 471         struct ehca_shca *shca = (struct ehca_shca*)dev_id;
 472
 473         tasklet_hi_schedule(&shca->neq.interrupt_task);
 474
 475         return IRQ_HANDLED;
 476 }
 477
 478 void ehca_tasklet_neq(unsigned long data)
 479 {
 480         struct ehca_shca *shca = (struct ehca_shca*)data;
 481         struct ehca_eqe *eqe;
 482         u64 ret;
 483
 484         eqe = ehca_poll_eq(shca, &shca->neq);
 485
 486         while (eqe) {
 487                 if (!EHCA_BMASK_GET(NEQE_COMPLETION_EVENT, eqe->entry))
 488                         parse_ec(shca, eqe->entry);
 489
 490                 eqe = ehca_poll_eq(shca, &shca->neq);
 491         }
 492
 493         ret = hipz_h_reset_event(shca->ipz_hca_handle,
 494                                  shca->neq.ipz_eq_handle, 0xFFFFFFFFFFFFFFFFL);
 495
 496         if (ret != H_SUCCESS)
 497                 ehca_err(&shca->ib_device, "Can't clear notification events.");
 498
 499         return;
 500 }
 501
 502 irqreturn_t ehca_interrupt_eq(int irq, void *dev_id)
 503 {
 504         struct ehca_shca *shca = (struct ehca_shca*)dev_id;
 505
 506         tasklet_hi_schedule(&shca->eq.interrupt_task);
 507
 508         return IRQ_HANDLED;
 509 }
 510
 511
 512 static inline void process_eqe(struct ehca_shca *shca, struct ehca_eqe *eqe)
 513 {
 514         u64 eqe_value;
 515         u32 token;
 516         struct ehca_cq *cq;
 517
 518         eqe_value = eqe->entry;
 519         ehca_dbg(&shca->ib_device, "eqe_value=%llx", eqe_value);
 520         if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
 521                 ehca_dbg(&shca->ib_device, "Got completion event");
 522                 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
 523                 read_lock(&ehca_cq_idr_lock);
 524                 cq = idr_find(&ehca_cq_idr, token);
 525                 if (cq)
 526                         atomic_inc(&cq->nr_events);
 527                 read_unlock(&ehca_cq_idr_lock);
 528                 if (cq == NULL) {
 529                         ehca_err(&shca->ib_device,
 530                                  "Invalid eqe for non-existing cq token=%x",
 531                                  token);
 532                         return;
 533                 }
 534                 reset_eq_pending(cq);
 535                 if (ehca_scaling_code)
 536                         queue_comp_task(cq);
 537                 else {
 538                         comp_event_callback(cq);
 539                         if (atomic_dec_and_test(&cq->nr_events))
 540                                 wake_up(&cq->wait_completion);
 541                 }
 542         } else {
 543                 ehca_dbg(&shca->ib_device, "Got non completion event");
 544                 parse_identifier(shca, eqe_value);
 545         }
 546 }
 547
 548 void ehca_process_eq(struct ehca_shca *shca, int is_irq)
 549 {
 550         struct ehca_eq *eq = &shca->eq;
 551         struct ehca_eqe_cache_entry *eqe_cache = eq->eqe_cache;
 552         u64 eqe_value, ret;
 553         int eqe_cnt, i;
 554         int eq_empty = 0;
 555
 556         spin_lock(&eq->irq_spinlock);
 557         if (is_irq) {
 558                 const int max_query_cnt = 100;
 559                 int query_cnt = 0;
 560                 int int_state = 1;
 561                 do {
 562                         int_state = hipz_h_query_int_state(
 563                                 shca->ipz_hca_handle, eq->ist);
 564                         query_cnt++;
 565                         iosync();
 566                 } while (int_state && query_cnt < max_query_cnt);
 567                 if (unlikely((query_cnt == max_query_cnt)))
 568                         ehca_dbg(&shca->ib_device, "int_state=%x query_cnt=%x",
 569                                  int_state, query_cnt);
 570         }
 571
 572         /* read out all eqes */
 573         eqe_cnt = 0;
 574         do {
 575                 u32 token;
 576                 eqe_cache[eqe_cnt].eqe = ehca_poll_eq(shca, eq);
 577                 if (!eqe_cache[eqe_cnt].eqe)
 578                         break;
 579                 eqe_value = eqe_cache[eqe_cnt].eqe->entry;
 580                 if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
 581                         token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
 582                         read_lock(&ehca_cq_idr_lock);
 583                         eqe_cache[eqe_cnt].cq = idr_find(&ehca_cq_idr, token);
 584                         if (eqe_cache[eqe_cnt].cq)
 585                                 atomic_inc(&eqe_cache[eqe_cnt].cq->nr_events);
 586                         read_unlock(&ehca_cq_idr_lock);
 587                         if (!eqe_cache[eqe_cnt].cq) {
 588                                 ehca_err(&shca->ib_device,
 589                                          "Invalid eqe for non-existing cq "
 590                                          "token=%x", token);
 591                                 continue;
 592                         }
 593                 } else
 594                         eqe_cache[eqe_cnt].cq = NULL;
 595                 eqe_cnt++;
 596         } while (eqe_cnt < EHCA_EQE_CACHE_SIZE);
 597         if (!eqe_cnt) {
 598                 if (is_irq)
 599                         ehca_dbg(&shca->ib_device,
 600                                  "No eqe found for irq event");
 601                 goto unlock_irq_spinlock;
 602         } else if (!is_irq) {
 603                 ret = hipz_h_eoi(eq->ist);
 604                 if (ret != H_SUCCESS)
 605                         ehca_err(&shca->ib_device,
 606                                  "bad return code EOI -rc = %lld\n", ret);
 607                 ehca_dbg(&shca->ib_device, "deadman found %x eqe", eqe_cnt);
 608         }
 609         if (unlikely(eqe_cnt == EHCA_EQE_CACHE_SIZE))
 610                 ehca_dbg(&shca->ib_device, "too many eqes for one irq event");
 611         /* enable irq for new packets */
 612         for (i = 0; i < eqe_cnt; i++) {
 613                 if (eq->eqe_cache[i].cq)
 614                         reset_eq_pending(eq->eqe_cache[i].cq);
 615         }
 616         /* check eq */
 617         spin_lock(&eq->spinlock);
 618         eq_empty = (!ipz_eqit_eq_peek_valid(&shca->eq.ipz_queue));
 619         spin_unlock(&eq->spinlock);
 620         /* call completion handler for cached eqes */
 621         for (i = 0; i < eqe_cnt; i++)
 622                 if (eq->eqe_cache[i].cq) {
 623                         if (ehca_scaling_code)
 624                                 queue_comp_task(eq->eqe_cache[i].cq);
 625                         else {
 626                                 struct ehca_cq *cq = eq->eqe_cache[i].cq;
 627                                 comp_event_callback(cq);
 628                                 if (atomic_dec_and_test(&cq->nr_events))
 629                                         wake_up(&cq->wait_completion);
 630                         }
 631                 } else {
 632                         ehca_dbg(&shca->ib_device, "Got non completion event");
 633                         parse_identifier(shca, eq->eqe_cache[i].eqe->entry);
 634                 }
 635         /* poll eq if not empty */
 636         if (eq_empty)
 637                 goto unlock_irq_spinlock;
 638         do {
 639                 struct ehca_eqe *eqe;
 640                 eqe = ehca_poll_eq(shca, &shca->eq);
 641                 if (!eqe)
 642                         break;
 643                 process_eqe(shca, eqe);
 644         } while (1);
 645
 646 unlock_irq_spinlock:
 647         spin_unlock(&eq->irq_spinlock);
 648 }
 649
 650 void ehca_tasklet_eq(unsigned long data)
 651 {
 652         ehca_process_eq((struct ehca_shca*)data, 1);
 653 }
 654
 655 static inline int find_next_online_cpu(struct ehca_comp_pool *pool)
 656 {
 657         int cpu;
 658         unsigned long flags;
 659
 660         WARN_ON_ONCE(!in_interrupt());
 661         if (ehca_debug_level >= 3)
 662                 ehca_dmp(cpu_online_mask, cpumask_size(), "");
 663
 664         spin_lock_irqsave(&pool->last_cpu_lock, flags);
 665         cpu = cpumask_next(pool->last_cpu, cpu_online_mask);
 666         if (cpu >= nr_cpu_ids)
 667                 cpu = cpumask_first(cpu_online_mask);
 668         pool->last_cpu = cpu;
 669         spin_unlock_irqrestore(&pool->last_cpu_lock, flags);
 670
 671         return cpu;
 672 }
 673
 674 static void __queue_comp_task(struct ehca_cq *__cq,
 675                               struct ehca_cpu_comp_task *cct)
 676 {
 677         unsigned long flags;
 678
 679         spin_lock_irqsave(&cct->task_lock, flags);
 680         spin_lock(&__cq->task_lock);
 681
 682         if (__cq->nr_callbacks == 0) {
 683                 __cq->nr_callbacks++;
 684                 list_add_tail(&__cq->entry, &cct->cq_list);
 685                 cct->cq_jobs++;
 686                 wake_up(&cct->wait_queue);
 687         } else
 688                 __cq->nr_callbacks++;
 689
 690         spin_unlock(&__cq->task_lock);
 691         spin_unlock_irqrestore(&cct->task_lock, flags);
 692 }
 693
 694 static void queue_comp_task(struct ehca_cq *__cq)
 695 {
 696         int cpu_id;
 697         struct ehca_cpu_comp_task *cct;
 698         int cq_jobs;
 699         unsigned long flags;
 700
 701         cpu_id = find_next_online_cpu(pool);
 702         BUG_ON(!cpu_online(cpu_id));
 703
 704         cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu_id);
 705         BUG_ON(!cct);
 706
 707         spin_lock_irqsave(&cct->task_lock, flags);
 708         cq_jobs = cct->cq_jobs;
 709         spin_unlock_irqrestore(&cct->task_lock, flags);
 710         if (cq_jobs > 0) {
 711                 cpu_id = find_next_online_cpu(pool);
 712                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu_id);
 713                 BUG_ON(!cct);
 714         }
 715
 716         __queue_comp_task(__cq, cct);
 717 }
 718
 719 static void run_comp_task(struct ehca_cpu_comp_task *cct)
 720 {
 721         struct ehca_cq *cq;
 722         unsigned long flags;
 723
 724         spin_lock_irqsave(&cct->task_lock, flags);
 725
 726         while (!list_empty(&cct->cq_list)) {
 727                 cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
 728                 spin_unlock_irqrestore(&cct->task_lock, flags);
 729
 730                 comp_event_callback(cq);
 731                 if (atomic_dec_and_test(&cq->nr_events))
 732                         wake_up(&cq->wait_completion);
 733
 734                 spin_lock_irqsave(&cct->task_lock, flags);
 735                 spin_lock(&cq->task_lock);
 736                 cq->nr_callbacks--;
 737                 if (!cq->nr_callbacks) {
 738                         list_del_init(cct->cq_list.next);
 739                         cct->cq_jobs--;
 740                 }
 741                 spin_unlock(&cq->task_lock);
 742         }
 743
 744         spin_unlock_irqrestore(&cct->task_lock, flags);
 745 }
 746
 747 static int comp_task(void *__cct)
 748 {
 749         struct ehca_cpu_comp_task *cct = __cct;
 750         int cql_empty;
 751         DECLARE_WAITQUEUE(wait, current);
 752
 753         set_current_state(TASK_INTERRUPTIBLE);
 754         while (!kthread_should_stop()) {
 755                 add_wait_queue(&cct->wait_queue, &wait);
 756
 757                 spin_lock_irq(&cct->task_lock);
 758                 cql_empty = list_empty(&cct->cq_list);
 759                 spin_unlock_irq(&cct->task_lock);
 760                 if (cql_empty)
 761                         schedule();
 762                 else
 763                         __set_current_state(TASK_RUNNING);
 764
 765                 remove_wait_queue(&cct->wait_queue, &wait);
 766
 767                 spin_lock_irq(&cct->task_lock);
 768                 cql_empty = list_empty(&cct->cq_list);
 769                 spin_unlock_irq(&cct->task_lock);
 770                 if (!cql_empty)
 771                         run_comp_task(__cct);
 772
 773                 set_current_state(TASK_INTERRUPTIBLE);
 774         }
 775         __set_current_state(TASK_RUNNING);
 776
 777         return 0;
 778 }
 779
 780 static struct task_struct *create_comp_task(struct ehca_comp_pool *pool,
 781                                             int cpu)
 782 {
 783         struct ehca_cpu_comp_task *cct;
 784
 785         cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 786         spin_lock_init(&cct->task_lock);
 787         INIT_LIST_HEAD(&cct->cq_list);
 788         init_waitqueue_head(&cct->wait_queue);
 789         cct->task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu);
 790
 791         return cct->task;
 792 }
 793
 794 static void destroy_comp_task(struct ehca_comp_pool *pool,
 795                               int cpu)
 796 {
 797         struct ehca_cpu_comp_task *cct;
 798         struct task_struct *task;
 799         unsigned long flags_cct;
 800
 801         cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 802
 803         spin_lock_irqsave(&cct->task_lock, flags_cct);
 804
 805         task = cct->task;
 806         cct->task = NULL;
 807         cct->cq_jobs = 0;
 808
 809         spin_unlock_irqrestore(&cct->task_lock, flags_cct);
 810
 811         if (task)
 812                 kthread_stop(task);
 813 }
 814
 815 static void __cpuinit take_over_work(struct ehca_comp_pool *pool, int cpu)
 816 {
 817         struct ehca_cpu_comp_task *cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 818         LIST_HEAD(list);
 819         struct ehca_cq *cq;
 820         unsigned long flags_cct;
 821
 822         spin_lock_irqsave(&cct->task_lock, flags_cct);
 823
 824         list_splice_init(&cct->cq_list, &list);
 825
 826         while (!list_empty(&list)) {
 827                 cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
 828
 829                 list_del(&cq->entry);
 830                 __queue_comp_task(cq, this_cpu_ptr(pool->cpu_comp_tasks));
 831         }
 832
 833         spin_unlock_irqrestore(&cct->task_lock, flags_cct);
 834
 835 }
 836
 837 static int __cpuinit comp_pool_callback(struct notifier_block *nfb,
 838                                         unsigned long action,
 839                                         void *hcpu)
 840 {
 841         unsigned int cpu = (unsigned long)hcpu;
 842         struct ehca_cpu_comp_task *cct;
 843
 844         switch (action) {
 845         case CPU_UP_PREPARE:
 846         case CPU_UP_PREPARE_FROZEN:
 847                 ehca_gen_dbg("CPU: %x (CPU_PREPARE)", cpu);
 848                 if (!create_comp_task(pool, cpu)) {
 849                         ehca_gen_err("Can't create comp_task for cpu: %x", cpu);
 850                         return NOTIFY_BAD;
 851                 }
 852                 break;
 853         case CPU_UP_CANCELED:
 854         case CPU_UP_CANCELED_FROZEN:
 855                 ehca_gen_dbg("CPU: %x (CPU_CANCELED)", cpu);
 856                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 857                 kthread_bind(cct->task, cpumask_any(cpu_online_mask));
 858                 destroy_comp_task(pool, cpu);
 859                 break;
 860         case CPU_ONLINE:
 861         case CPU_ONLINE_FROZEN:
 862                 ehca_gen_dbg("CPU: %x (CPU_ONLINE)", cpu);
 863                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 864                 kthread_bind(cct->task, cpu);
 865                 wake_up_process(cct->task);
 866                 break;
 867         case CPU_DOWN_PREPARE:
 868         case CPU_DOWN_PREPARE_FROZEN:
 869                 ehca_gen_dbg("CPU: %x (CPU_DOWN_PREPARE)", cpu);
 870                 break;
 871         case CPU_DOWN_FAILED:
 872         case CPU_DOWN_FAILED_FROZEN:
 873                 ehca_gen_dbg("CPU: %x (CPU_DOWN_FAILED)", cpu);
 874                 break;
 875         case CPU_DEAD:
 876         case CPU_DEAD_FROZEN:
 877                 ehca_gen_dbg("CPU: %x (CPU_DEAD)", cpu);
 878                 destroy_comp_task(pool, cpu);
 879                 take_over_work(pool, cpu);
 880                 break;
 881         }
 882
 883         return NOTIFY_OK;
 884 }
 885
 886 static struct notifier_block comp_pool_callback_nb __cpuinitdata = {
 887         .notifier_call  = comp_pool_callback,
 888         .priority       = 0,
 889 };
 890
 891 int ehca_create_comp_pool(void)
 892 {
 893         int cpu;
 894         struct task_struct *task;
 895
 896         if (!ehca_scaling_code)
 897                 return 0;
 898
 899         pool = kzalloc(sizeof(struct ehca_comp_pool), GFP_KERNEL);
 900         if (pool == NULL)
 901                 return -ENOMEM;
 902
 903         spin_lock_init(&pool->last_cpu_lock);
 904         pool->last_cpu = cpumask_any(cpu_online_mask);
 905
 906         pool->cpu_comp_tasks = alloc_percpu(struct ehca_cpu_comp_task);
 907         if (pool->cpu_comp_tasks == NULL) {
 908                 kfree(pool);
 909                 return -EINVAL;
 910         }
 911
 912         for_each_online_cpu(cpu) {
 913                 task = create_comp_task(pool, cpu);
 914                 if (task) {
 915                         kthread_bind(task, cpu);
 916                         wake_up_process(task);
 917                 }
 918         }
 919
 920         register_hotcpu_notifier(&comp_pool_callback_nb);
 921
 922         printk(KERN_INFO "eHCA scaling code enabled\n");
 923
 924         return 0;
 925 }
 926
 927 void ehca_destroy_comp_pool(void)
 928 {
 929         int i;
 930
 931         if (!ehca_scaling_code)
 932                 return;
 933
 934         unregister_hotcpu_notifier(&comp_pool_callback_nb);
 935
 936         for_each_online_cpu(i)
 937                 destroy_comp_task(pool, i);
 938
 939         free_percpu(pool->cpu_comp_tasks);
 940         kfree(pool);
 941 }