include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[linux-3.10.git] / 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 }