]> nv-tegra.nvidia Code Review - linux-2.6.git/blob - drivers/infiniband/hw/ehca/ehca_irq.c
Merge branch 'linus' into cpus4096
[linux-2.6.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 "ehca_classes.h"
45 #include "ehca_irq.h"
46 #include "ehca_iverbs.h"
47 #include "ehca_tools.h"
48 #include "hcp_if.h"
49 #include "hipz_fns.h"
50 #include "ipz_pt_fn.h"
51
52 #define EQE_COMPLETION_EVENT   EHCA_BMASK_IBM( 1,  1)
53 #define EQE_CQ_QP_NUMBER       EHCA_BMASK_IBM( 8, 31)
54 #define EQE_EE_IDENTIFIER      EHCA_BMASK_IBM( 2,  7)
55 #define EQE_CQ_NUMBER          EHCA_BMASK_IBM( 8, 31)
56 #define EQE_QP_NUMBER          EHCA_BMASK_IBM( 8, 31)
57 #define EQE_QP_TOKEN           EHCA_BMASK_IBM(32, 63)
58 #define EQE_CQ_TOKEN           EHCA_BMASK_IBM(32, 63)
59
60 #define NEQE_COMPLETION_EVENT  EHCA_BMASK_IBM( 1,  1)
61 #define NEQE_EVENT_CODE        EHCA_BMASK_IBM( 2,  7)
62 #define NEQE_PORT_NUMBER       EHCA_BMASK_IBM( 8, 15)
63 #define NEQE_PORT_AVAILABILITY EHCA_BMASK_IBM(16, 16)
64 #define NEQE_DISRUPTIVE        EHCA_BMASK_IBM(16, 16)
65 #define NEQE_SPECIFIC_EVENT    EHCA_BMASK_IBM(16, 23)
66
67 #define ERROR_DATA_LENGTH      EHCA_BMASK_IBM(52, 63)
68 #define ERROR_DATA_TYPE        EHCA_BMASK_IBM( 0,  7)
69
70 static void queue_comp_task(struct ehca_cq *__cq);
71
72 static struct ehca_comp_pool *pool;
73
74 static inline void comp_event_callback(struct ehca_cq *cq)
75 {
76         if (!cq->ib_cq.comp_handler)
77                 return;
78
79         spin_lock(&cq->cb_lock);
80         cq->ib_cq.comp_handler(&cq->ib_cq, cq->ib_cq.cq_context);
81         spin_unlock(&cq->cb_lock);
82
83         return;
84 }
85
86 static void print_error_data(struct ehca_shca *shca, void *data,
87                              u64 *rblock, int length)
88 {
89         u64 type = EHCA_BMASK_GET(ERROR_DATA_TYPE, rblock[2]);
90         u64 resource = rblock[1];
91
92         switch (type) {
93         case 0x1: /* Queue Pair */
94         {
95                 struct ehca_qp *qp = (struct ehca_qp *)data;
96
97                 /* only print error data if AER is set */
98                 if (rblock[6] == 0)
99                         return;
100
101                 ehca_err(&shca->ib_device,
102                          "QP 0x%x (resource=%lx) has errors.",
103                          qp->ib_qp.qp_num, resource);
104                 break;
105         }
106         case 0x4: /* Completion Queue */
107         {
108                 struct ehca_cq *cq = (struct ehca_cq *)data;
109
110                 ehca_err(&shca->ib_device,
111                          "CQ 0x%x (resource=%lx) has errors.",
112                          cq->cq_number, resource);
113                 break;
114         }
115         default:
116                 ehca_err(&shca->ib_device,
117                          "Unknown error type: %lx on %s.",
118                          type, shca->ib_device.name);
119                 break;
120         }
121
122         ehca_err(&shca->ib_device, "Error data is available: %lx.", resource);
123         ehca_err(&shca->ib_device, "EHCA ----- error data begin "
124                  "---------------------------------------------------");
125         ehca_dmp(rblock, length, "resource=%lx", resource);
126         ehca_err(&shca->ib_device, "EHCA ----- error data end "
127                  "----------------------------------------------------");
128
129         return;
130 }
131
132 int ehca_error_data(struct ehca_shca *shca, void *data,
133                     u64 resource)
134 {
135
136         unsigned long ret;
137         u64 *rblock;
138         unsigned long block_count;
139
140         rblock = ehca_alloc_fw_ctrlblock(GFP_ATOMIC);
141         if (!rblock) {
142                 ehca_err(&shca->ib_device, "Cannot allocate rblock memory.");
143                 ret = -ENOMEM;
144                 goto error_data1;
145         }
146
147         /* rblock must be 4K aligned and should be 4K large */
148         ret = hipz_h_error_data(shca->ipz_hca_handle,
149                                 resource,
150                                 rblock,
151                                 &block_count);
152
153         if (ret == H_R_STATE)
154                 ehca_err(&shca->ib_device,
155                          "No error data is available: %lx.", resource);
156         else if (ret == H_SUCCESS) {
157                 int length;
158
159                 length = EHCA_BMASK_GET(ERROR_DATA_LENGTH, rblock[0]);
160
161                 if (length > EHCA_PAGESIZE)
162                         length = EHCA_PAGESIZE;
163
164                 print_error_data(shca, data, rblock, length);
165         } else
166                 ehca_err(&shca->ib_device,
167                          "Error data could not be fetched: %lx", resource);
168
169         ehca_free_fw_ctrlblock(rblock);
170
171 error_data1:
172         return ret;
173
174 }
175
176 static void dispatch_qp_event(struct ehca_shca *shca, struct ehca_qp *qp,
177                               enum ib_event_type event_type)
178 {
179         struct ib_event event;
180
181         event.device = &shca->ib_device;
182         event.event = event_type;
183
184         if (qp->ext_type == EQPT_SRQ) {
185                 if (!qp->ib_srq.event_handler)
186                         return;
187
188                 event.element.srq = &qp->ib_srq;
189                 qp->ib_srq.event_handler(&event, qp->ib_srq.srq_context);
190         } else {
191                 if (!qp->ib_qp.event_handler)
192                         return;
193
194                 event.element.qp = &qp->ib_qp;
195                 qp->ib_qp.event_handler(&event, qp->ib_qp.qp_context);
196         }
197 }
198
199 static void qp_event_callback(struct ehca_shca *shca, u64 eqe,
200                               enum ib_event_type event_type, int fatal)
201 {
202         struct ehca_qp *qp;
203         u32 token = EHCA_BMASK_GET(EQE_QP_TOKEN, eqe);
204
205         read_lock(&ehca_qp_idr_lock);
206         qp = idr_find(&ehca_qp_idr, token);
207         if (qp)
208                 atomic_inc(&qp->nr_events);
209         read_unlock(&ehca_qp_idr_lock);
210
211         if (!qp)
212                 return;
213
214         if (fatal)
215                 ehca_error_data(shca, qp, qp->ipz_qp_handle.handle);
216
217         dispatch_qp_event(shca, qp, fatal && qp->ext_type == EQPT_SRQ ?
218                           IB_EVENT_SRQ_ERR : event_type);
219
220         /*
221          * eHCA only processes one WQE at a time for SRQ base QPs,
222          * so the last WQE has been processed as soon as the QP enters
223          * error state.
224          */
225         if (fatal && qp->ext_type == EQPT_SRQBASE)
226                 dispatch_qp_event(shca, qp, IB_EVENT_QP_LAST_WQE_REACHED);
227
228         if (atomic_dec_and_test(&qp->nr_events))
229                 wake_up(&qp->wait_completion);
230         return;
231 }
232
233 static void cq_event_callback(struct ehca_shca *shca,
234                               u64 eqe)
235 {
236         struct ehca_cq *cq;
237         u32 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe);
238
239         read_lock(&ehca_cq_idr_lock);
240         cq = idr_find(&ehca_cq_idr, token);
241         if (cq)
242                 atomic_inc(&cq->nr_events);
243         read_unlock(&ehca_cq_idr_lock);
244
245         if (!cq)
246                 return;
247
248         ehca_error_data(shca, cq, cq->ipz_cq_handle.handle);
249
250         if (atomic_dec_and_test(&cq->nr_events))
251                 wake_up(&cq->wait_completion);
252
253         return;
254 }
255
256 static void parse_identifier(struct ehca_shca *shca, u64 eqe)
257 {
258         u8 identifier = EHCA_BMASK_GET(EQE_EE_IDENTIFIER, eqe);
259
260         switch (identifier) {
261         case 0x02: /* path migrated */
262                 qp_event_callback(shca, eqe, IB_EVENT_PATH_MIG, 0);
263                 break;
264         case 0x03: /* communication established */
265                 qp_event_callback(shca, eqe, IB_EVENT_COMM_EST, 0);
266                 break;
267         case 0x04: /* send queue drained */
268                 qp_event_callback(shca, eqe, IB_EVENT_SQ_DRAINED, 0);
269                 break;
270         case 0x05: /* QP error */
271         case 0x06: /* QP error */
272                 qp_event_callback(shca, eqe, IB_EVENT_QP_FATAL, 1);
273                 break;
274         case 0x07: /* CQ error */
275         case 0x08: /* CQ error */
276                 cq_event_callback(shca, eqe);
277                 break;
278         case 0x09: /* MRMWPTE error */
279                 ehca_err(&shca->ib_device, "MRMWPTE error.");
280                 break;
281         case 0x0A: /* port event */
282                 ehca_err(&shca->ib_device, "Port event.");
283                 break;
284         case 0x0B: /* MR access error */
285                 ehca_err(&shca->ib_device, "MR access error.");
286                 break;
287         case 0x0C: /* EQ error */
288                 ehca_err(&shca->ib_device, "EQ error.");
289                 break;
290         case 0x0D: /* P/Q_Key mismatch */
291                 ehca_err(&shca->ib_device, "P/Q_Key mismatch.");
292                 break;
293         case 0x10: /* sampling complete */
294                 ehca_err(&shca->ib_device, "Sampling complete.");
295                 break;
296         case 0x11: /* unaffiliated access error */
297                 ehca_err(&shca->ib_device, "Unaffiliated access error.");
298                 break;
299         case 0x12: /* path migrating */
300                 ehca_err(&shca->ib_device, "Path migrating.");
301                 break;
302         case 0x13: /* interface trace stopped */
303                 ehca_err(&shca->ib_device, "Interface trace stopped.");
304                 break;
305         case 0x14: /* first error capture info available */
306                 ehca_info(&shca->ib_device, "First error capture available");
307                 break;
308         case 0x15: /* SRQ limit reached */
309                 qp_event_callback(shca, eqe, IB_EVENT_SRQ_LIMIT_REACHED, 0);
310                 break;
311         default:
312                 ehca_err(&shca->ib_device, "Unknown identifier: %x on %s.",
313                          identifier, shca->ib_device.name);
314                 break;
315         }
316
317         return;
318 }
319
320 static void dispatch_port_event(struct ehca_shca *shca, int port_num,
321                                 enum ib_event_type type, const char *msg)
322 {
323         struct ib_event event;
324
325         ehca_info(&shca->ib_device, "port %d %s.", port_num, msg);
326         event.device = &shca->ib_device;
327         event.event = type;
328         event.element.port_num = port_num;
329         ib_dispatch_event(&event);
330 }
331
332 static void notify_port_conf_change(struct ehca_shca *shca, int port_num)
333 {
334         struct ehca_sma_attr  new_attr;
335         struct ehca_sma_attr *old_attr = &shca->sport[port_num - 1].saved_attr;
336
337         ehca_query_sma_attr(shca, port_num, &new_attr);
338
339         if (new_attr.sm_sl  != old_attr->sm_sl ||
340             new_attr.sm_lid != old_attr->sm_lid)
341                 dispatch_port_event(shca, port_num, IB_EVENT_SM_CHANGE,
342                                     "SM changed");
343
344         if (new_attr.lid != old_attr->lid ||
345             new_attr.lmc != old_attr->lmc)
346                 dispatch_port_event(shca, port_num, IB_EVENT_LID_CHANGE,
347                                     "LID changed");
348
349         if (new_attr.pkey_tbl_len != old_attr->pkey_tbl_len ||
350             memcmp(new_attr.pkeys, old_attr->pkeys,
351                    sizeof(u16) * new_attr.pkey_tbl_len))
352                 dispatch_port_event(shca, port_num, IB_EVENT_PKEY_CHANGE,
353                                     "P_Key changed");
354
355         *old_attr = new_attr;
356 }
357
358 static void parse_ec(struct ehca_shca *shca, u64 eqe)
359 {
360         u8 ec   = EHCA_BMASK_GET(NEQE_EVENT_CODE, eqe);
361         u8 port = EHCA_BMASK_GET(NEQE_PORT_NUMBER, eqe);
362         u8 spec_event;
363         struct ehca_sport *sport = &shca->sport[port - 1];
364         unsigned long flags;
365
366         switch (ec) {
367         case 0x30: /* port availability change */
368                 if (EHCA_BMASK_GET(NEQE_PORT_AVAILABILITY, eqe)) {
369                         int suppress_event;
370                         /* replay modify_qp for sqps */
371                         spin_lock_irqsave(&sport->mod_sqp_lock, flags);
372                         suppress_event = !sport->ibqp_sqp[IB_QPT_GSI];
373                         if (sport->ibqp_sqp[IB_QPT_SMI])
374                                 ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_SMI]);
375                         if (!suppress_event)
376                                 ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_GSI]);
377                         spin_unlock_irqrestore(&sport->mod_sqp_lock, flags);
378
379                         /* AQP1 was destroyed, ignore this event */
380                         if (suppress_event)
381                                 break;
382
383                         sport->port_state = IB_PORT_ACTIVE;
384                         dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
385                                             "is active");
386                         ehca_query_sma_attr(shca, port,
387                                             &sport->saved_attr);
388                 } else {
389                         sport->port_state = IB_PORT_DOWN;
390                         dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
391                                             "is inactive");
392                 }
393                 break;
394         case 0x31:
395                 /* port configuration change
396                  * disruptive change is caused by
397                  * LID, PKEY or SM change
398                  */
399                 if (EHCA_BMASK_GET(NEQE_DISRUPTIVE, eqe)) {
400                         ehca_warn(&shca->ib_device, "disruptive port "
401                                   "%d configuration change", port);
402
403                         sport->port_state = IB_PORT_DOWN;
404                         dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
405                                             "is inactive");
406
407                         sport->port_state = IB_PORT_ACTIVE;
408                         dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
409                                             "is active");
410                         ehca_query_sma_attr(shca, port,
411                                             &sport->saved_attr);
412                 } else
413                         notify_port_conf_change(shca, port);
414                 break;
415         case 0x32: /* adapter malfunction */
416                 ehca_err(&shca->ib_device, "Adapter malfunction.");
417                 break;
418         case 0x33:  /* trace stopped */
419                 ehca_err(&shca->ib_device, "Traced stopped.");
420                 break;
421         case 0x34: /* util async event */
422                 spec_event = EHCA_BMASK_GET(NEQE_SPECIFIC_EVENT, eqe);
423                 if (spec_event == 0x80) /* client reregister required */
424                         dispatch_port_event(shca, port,
425                                             IB_EVENT_CLIENT_REREGISTER,
426                                             "client reregister req.");
427                 else
428                         ehca_warn(&shca->ib_device, "Unknown util async "
429                                   "event %x on port %x", spec_event, port);
430                 break;
431         default:
432                 ehca_err(&shca->ib_device, "Unknown event code: %x on %s.",
433                          ec, shca->ib_device.name);
434                 break;
435         }
436
437         return;
438 }
439
440 static inline void reset_eq_pending(struct ehca_cq *cq)
441 {
442         u64 CQx_EP;
443         struct h_galpa gal = cq->galpas.kernel;
444
445         hipz_galpa_store_cq(gal, cqx_ep, 0x0);
446         CQx_EP = hipz_galpa_load(gal, CQTEMM_OFFSET(cqx_ep));
447
448         return;
449 }
450
451 irqreturn_t ehca_interrupt_neq(int irq, void *dev_id)
452 {
453         struct ehca_shca *shca = (struct ehca_shca*)dev_id;
454
455         tasklet_hi_schedule(&shca->neq.interrupt_task);
456
457         return IRQ_HANDLED;
458 }
459
460 void ehca_tasklet_neq(unsigned long data)
461 {
462         struct ehca_shca *shca = (struct ehca_shca*)data;
463         struct ehca_eqe *eqe;
464         u64 ret;
465
466         eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->neq);
467
468         while (eqe) {
469                 if (!EHCA_BMASK_GET(NEQE_COMPLETION_EVENT, eqe->entry))
470                         parse_ec(shca, eqe->entry);
471
472                 eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->neq);
473         }
474
475         ret = hipz_h_reset_event(shca->ipz_hca_handle,
476                                  shca->neq.ipz_eq_handle, 0xFFFFFFFFFFFFFFFFL);
477
478         if (ret != H_SUCCESS)
479                 ehca_err(&shca->ib_device, "Can't clear notification events.");
480
481         return;
482 }
483
484 irqreturn_t ehca_interrupt_eq(int irq, void *dev_id)
485 {
486         struct ehca_shca *shca = (struct ehca_shca*)dev_id;
487
488         tasklet_hi_schedule(&shca->eq.interrupt_task);
489
490         return IRQ_HANDLED;
491 }
492
493
494 static inline void process_eqe(struct ehca_shca *shca, struct ehca_eqe *eqe)
495 {
496         u64 eqe_value;
497         u32 token;
498         struct ehca_cq *cq;
499
500         eqe_value = eqe->entry;
501         ehca_dbg(&shca->ib_device, "eqe_value=%lx", eqe_value);
502         if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
503                 ehca_dbg(&shca->ib_device, "Got completion event");
504                 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
505                 read_lock(&ehca_cq_idr_lock);
506                 cq = idr_find(&ehca_cq_idr, token);
507                 if (cq)
508                         atomic_inc(&cq->nr_events);
509                 read_unlock(&ehca_cq_idr_lock);
510                 if (cq == NULL) {
511                         ehca_err(&shca->ib_device,
512                                  "Invalid eqe for non-existing cq token=%x",
513                                  token);
514                         return;
515                 }
516                 reset_eq_pending(cq);
517                 if (ehca_scaling_code)
518                         queue_comp_task(cq);
519                 else {
520                         comp_event_callback(cq);
521                         if (atomic_dec_and_test(&cq->nr_events))
522                                 wake_up(&cq->wait_completion);
523                 }
524         } else {
525                 ehca_dbg(&shca->ib_device, "Got non completion event");
526                 parse_identifier(shca, eqe_value);
527         }
528 }
529
530 void ehca_process_eq(struct ehca_shca *shca, int is_irq)
531 {
532         struct ehca_eq *eq = &shca->eq;
533         struct ehca_eqe_cache_entry *eqe_cache = eq->eqe_cache;
534         u64 eqe_value, ret;
535         unsigned long flags;
536         int eqe_cnt, i;
537         int eq_empty = 0;
538
539         spin_lock_irqsave(&eq->irq_spinlock, flags);
540         if (is_irq) {
541                 const int max_query_cnt = 100;
542                 int query_cnt = 0;
543                 int int_state = 1;
544                 do {
545                         int_state = hipz_h_query_int_state(
546                                 shca->ipz_hca_handle, eq->ist);
547                         query_cnt++;
548                         iosync();
549                 } while (int_state && query_cnt < max_query_cnt);
550                 if (unlikely((query_cnt == max_query_cnt)))
551                         ehca_dbg(&shca->ib_device, "int_state=%x query_cnt=%x",
552                                  int_state, query_cnt);
553         }
554
555         /* read out all eqes */
556         eqe_cnt = 0;
557         do {
558                 u32 token;
559                 eqe_cache[eqe_cnt].eqe =
560                         (struct ehca_eqe *)ehca_poll_eq(shca, eq);
561                 if (!eqe_cache[eqe_cnt].eqe)
562                         break;
563                 eqe_value = eqe_cache[eqe_cnt].eqe->entry;
564                 if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
565                         token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
566                         read_lock(&ehca_cq_idr_lock);
567                         eqe_cache[eqe_cnt].cq = idr_find(&ehca_cq_idr, token);
568                         if (eqe_cache[eqe_cnt].cq)
569                                 atomic_inc(&eqe_cache[eqe_cnt].cq->nr_events);
570                         read_unlock(&ehca_cq_idr_lock);
571                         if (!eqe_cache[eqe_cnt].cq) {
572                                 ehca_err(&shca->ib_device,
573                                          "Invalid eqe for non-existing cq "
574                                          "token=%x", token);
575                                 continue;
576                         }
577                 } else
578                         eqe_cache[eqe_cnt].cq = NULL;
579                 eqe_cnt++;
580         } while (eqe_cnt < EHCA_EQE_CACHE_SIZE);
581         if (!eqe_cnt) {
582                 if (is_irq)
583                         ehca_dbg(&shca->ib_device,
584                                  "No eqe found for irq event");
585                 goto unlock_irq_spinlock;
586         } else if (!is_irq) {
587                 ret = hipz_h_eoi(eq->ist);
588                 if (ret != H_SUCCESS)
589                         ehca_err(&shca->ib_device,
590                                  "bad return code EOI -rc = %ld\n", ret);
591                 ehca_dbg(&shca->ib_device, "deadman found %x eqe", eqe_cnt);
592         }
593         if (unlikely(eqe_cnt == EHCA_EQE_CACHE_SIZE))
594                 ehca_dbg(&shca->ib_device, "too many eqes for one irq event");
595         /* enable irq for new packets */
596         for (i = 0; i < eqe_cnt; i++) {
597                 if (eq->eqe_cache[i].cq)
598                         reset_eq_pending(eq->eqe_cache[i].cq);
599         }
600         /* check eq */
601         spin_lock(&eq->spinlock);
602         eq_empty = (!ipz_eqit_eq_peek_valid(&shca->eq.ipz_queue));
603         spin_unlock(&eq->spinlock);
604         /* call completion handler for cached eqes */
605         for (i = 0; i < eqe_cnt; i++)
606                 if (eq->eqe_cache[i].cq) {
607                         if (ehca_scaling_code)
608                                 queue_comp_task(eq->eqe_cache[i].cq);
609                         else {
610                                 struct ehca_cq *cq = eq->eqe_cache[i].cq;
611                                 comp_event_callback(cq);
612                                 if (atomic_dec_and_test(&cq->nr_events))
613                                         wake_up(&cq->wait_completion);
614                         }
615                 } else {
616                         ehca_dbg(&shca->ib_device, "Got non completion event");
617                         parse_identifier(shca, eq->eqe_cache[i].eqe->entry);
618                 }
619         /* poll eq if not empty */
620         if (eq_empty)
621                 goto unlock_irq_spinlock;
622         do {
623                 struct ehca_eqe *eqe;
624                 eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->eq);
625                 if (!eqe)
626                         break;
627                 process_eqe(shca, eqe);
628         } while (1);
629
630 unlock_irq_spinlock:
631         spin_unlock_irqrestore(&eq->irq_spinlock, flags);
632 }
633
634 void ehca_tasklet_eq(unsigned long data)
635 {
636         ehca_process_eq((struct ehca_shca*)data, 1);
637 }
638
639 static inline int find_next_online_cpu(struct ehca_comp_pool *pool)
640 {
641         int cpu;
642         unsigned long flags;
643
644         WARN_ON_ONCE(!in_interrupt());
645         if (ehca_debug_level >= 3)
646                 ehca_dmp(&cpu_online_map, sizeof(cpumask_t), "");
647
648         spin_lock_irqsave(&pool->last_cpu_lock, flags);
649         cpu = next_cpu_nr(pool->last_cpu, cpu_online_map);
650         if (cpu >= nr_cpu_ids)
651                 cpu = first_cpu(cpu_online_map);
652         pool->last_cpu = cpu;
653         spin_unlock_irqrestore(&pool->last_cpu_lock, flags);
654
655         return cpu;
656 }
657
658 static void __queue_comp_task(struct ehca_cq *__cq,
659                               struct ehca_cpu_comp_task *cct)
660 {
661         unsigned long flags;
662
663         spin_lock_irqsave(&cct->task_lock, flags);
664         spin_lock(&__cq->task_lock);
665
666         if (__cq->nr_callbacks == 0) {
667                 __cq->nr_callbacks++;
668                 list_add_tail(&__cq->entry, &cct->cq_list);
669                 cct->cq_jobs++;
670                 wake_up(&cct->wait_queue);
671         } else
672                 __cq->nr_callbacks++;
673
674         spin_unlock(&__cq->task_lock);
675         spin_unlock_irqrestore(&cct->task_lock, flags);
676 }
677
678 static void queue_comp_task(struct ehca_cq *__cq)
679 {
680         int cpu_id;
681         struct ehca_cpu_comp_task *cct;
682         int cq_jobs;
683         unsigned long flags;
684
685         cpu_id = find_next_online_cpu(pool);
686         BUG_ON(!cpu_online(cpu_id));
687
688         cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu_id);
689         BUG_ON(!cct);
690
691         spin_lock_irqsave(&cct->task_lock, flags);
692         cq_jobs = cct->cq_jobs;
693         spin_unlock_irqrestore(&cct->task_lock, flags);
694         if (cq_jobs > 0) {
695                 cpu_id = find_next_online_cpu(pool);
696                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu_id);
697                 BUG_ON(!cct);
698         }
699
700         __queue_comp_task(__cq, cct);
701 }
702
703 static void run_comp_task(struct ehca_cpu_comp_task *cct)
704 {
705         struct ehca_cq *cq;
706         unsigned long flags;
707
708         spin_lock_irqsave(&cct->task_lock, flags);
709
710         while (!list_empty(&cct->cq_list)) {
711                 cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
712                 spin_unlock_irqrestore(&cct->task_lock, flags);
713
714                 comp_event_callback(cq);
715                 if (atomic_dec_and_test(&cq->nr_events))
716                         wake_up(&cq->wait_completion);
717
718                 spin_lock_irqsave(&cct->task_lock, flags);
719                 spin_lock(&cq->task_lock);
720                 cq->nr_callbacks--;
721                 if (!cq->nr_callbacks) {
722                         list_del_init(cct->cq_list.next);
723                         cct->cq_jobs--;
724                 }
725                 spin_unlock(&cq->task_lock);
726         }
727
728         spin_unlock_irqrestore(&cct->task_lock, flags);
729 }
730
731 static int comp_task(void *__cct)
732 {
733         struct ehca_cpu_comp_task *cct = __cct;
734         int cql_empty;
735         DECLARE_WAITQUEUE(wait, current);
736
737         set_current_state(TASK_INTERRUPTIBLE);
738         while (!kthread_should_stop()) {
739                 add_wait_queue(&cct->wait_queue, &wait);
740
741                 spin_lock_irq(&cct->task_lock);
742                 cql_empty = list_empty(&cct->cq_list);
743                 spin_unlock_irq(&cct->task_lock);
744                 if (cql_empty)
745                         schedule();
746                 else
747                         __set_current_state(TASK_RUNNING);
748
749                 remove_wait_queue(&cct->wait_queue, &wait);
750
751                 spin_lock_irq(&cct->task_lock);
752                 cql_empty = list_empty(&cct->cq_list);
753                 spin_unlock_irq(&cct->task_lock);
754                 if (!cql_empty)
755                         run_comp_task(__cct);
756
757                 set_current_state(TASK_INTERRUPTIBLE);
758         }
759         __set_current_state(TASK_RUNNING);
760
761         return 0;
762 }
763
764 static struct task_struct *create_comp_task(struct ehca_comp_pool *pool,
765                                             int cpu)
766 {
767         struct ehca_cpu_comp_task *cct;
768
769         cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
770         spin_lock_init(&cct->task_lock);
771         INIT_LIST_HEAD(&cct->cq_list);
772         init_waitqueue_head(&cct->wait_queue);
773         cct->task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu);
774
775         return cct->task;
776 }
777
778 static void destroy_comp_task(struct ehca_comp_pool *pool,
779                               int cpu)
780 {
781         struct ehca_cpu_comp_task *cct;
782         struct task_struct *task;
783         unsigned long flags_cct;
784
785         cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
786
787         spin_lock_irqsave(&cct->task_lock, flags_cct);
788
789         task = cct->task;
790         cct->task = NULL;
791         cct->cq_jobs = 0;
792
793         spin_unlock_irqrestore(&cct->task_lock, flags_cct);
794
795         if (task)
796                 kthread_stop(task);
797 }
798
799 static void __cpuinit take_over_work(struct ehca_comp_pool *pool, int cpu)
800 {
801         struct ehca_cpu_comp_task *cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
802         LIST_HEAD(list);
803         struct ehca_cq *cq;
804         unsigned long flags_cct;
805
806         spin_lock_irqsave(&cct->task_lock, flags_cct);
807
808         list_splice_init(&cct->cq_list, &list);
809
810         while (!list_empty(&list)) {
811                 cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
812
813                 list_del(&cq->entry);
814                 __queue_comp_task(cq, per_cpu_ptr(pool->cpu_comp_tasks,
815                                                   smp_processor_id()));
816         }
817
818         spin_unlock_irqrestore(&cct->task_lock, flags_cct);
819
820 }
821
822 static int __cpuinit comp_pool_callback(struct notifier_block *nfb,
823                                         unsigned long action,
824                                         void *hcpu)
825 {
826         unsigned int cpu = (unsigned long)hcpu;
827         struct ehca_cpu_comp_task *cct;
828
829         switch (action) {
830         case CPU_UP_PREPARE:
831         case CPU_UP_PREPARE_FROZEN:
832                 ehca_gen_dbg("CPU: %x (CPU_PREPARE)", cpu);
833                 if (!create_comp_task(pool, cpu)) {
834                         ehca_gen_err("Can't create comp_task for cpu: %x", cpu);
835                         return NOTIFY_BAD;
836                 }
837                 break;
838         case CPU_UP_CANCELED:
839         case CPU_UP_CANCELED_FROZEN:
840                 ehca_gen_dbg("CPU: %x (CPU_CANCELED)", cpu);
841                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
842                 kthread_bind(cct->task, any_online_cpu(cpu_online_map));
843                 destroy_comp_task(pool, cpu);
844                 break;
845         case CPU_ONLINE:
846         case CPU_ONLINE_FROZEN:
847                 ehca_gen_dbg("CPU: %x (CPU_ONLINE)", cpu);
848                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
849                 kthread_bind(cct->task, cpu);
850                 wake_up_process(cct->task);
851                 break;
852         case CPU_DOWN_PREPARE:
853         case CPU_DOWN_PREPARE_FROZEN:
854                 ehca_gen_dbg("CPU: %x (CPU_DOWN_PREPARE)", cpu);
855                 break;
856         case CPU_DOWN_FAILED:
857         case CPU_DOWN_FAILED_FROZEN:
858                 ehca_gen_dbg("CPU: %x (CPU_DOWN_FAILED)", cpu);
859                 break;
860         case CPU_DEAD:
861         case CPU_DEAD_FROZEN:
862                 ehca_gen_dbg("CPU: %x (CPU_DEAD)", cpu);
863                 destroy_comp_task(pool, cpu);
864                 take_over_work(pool, cpu);
865                 break;
866         }
867
868         return NOTIFY_OK;
869 }
870
871 static struct notifier_block comp_pool_callback_nb __cpuinitdata = {
872         .notifier_call  = comp_pool_callback,
873         .priority       = 0,
874 };
875
876 int ehca_create_comp_pool(void)
877 {
878         int cpu;
879         struct task_struct *task;
880
881         if (!ehca_scaling_code)
882                 return 0;
883
884         pool = kzalloc(sizeof(struct ehca_comp_pool), GFP_KERNEL);
885         if (pool == NULL)
886                 return -ENOMEM;
887
888         spin_lock_init(&pool->last_cpu_lock);
889         pool->last_cpu = any_online_cpu(cpu_online_map);
890
891         pool->cpu_comp_tasks = alloc_percpu(struct ehca_cpu_comp_task);
892         if (pool->cpu_comp_tasks == NULL) {
893                 kfree(pool);
894                 return -EINVAL;
895         }
896
897         for_each_online_cpu(cpu) {
898                 task = create_comp_task(pool, cpu);
899                 if (task) {
900                         kthread_bind(task, cpu);
901                         wake_up_process(task);
902                 }
903         }
904
905         register_hotcpu_notifier(&comp_pool_callback_nb);
906
907         printk(KERN_INFO "eHCA scaling code enabled\n");
908
909         return 0;
910 }
911
912 void ehca_destroy_comp_pool(void)
913 {
914         int i;
915
916         if (!ehca_scaling_code)
917                 return;
918
919         unregister_hotcpu_notifier(&comp_pool_callback_nb);
920
921         for (i = 0; i < NR_CPUS; i++) {
922                 if (cpu_online(i))
923                         destroy_comp_task(pool, i);
924         }
925         free_percpu(pool->cpu_comp_tasks);
926         kfree(pool);
927 }