]> nv-tegra.nvidia Code Review - linux-2.6.git/blob - drivers/infiniband/hw/ehca/ehca_irq.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6
[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         /* PATH_MIG without the QP ever having been armed is false alarm */
182         if (event_type == IB_EVENT_PATH_MIG && !qp->mig_armed)
183                 return;
184
185         event.device = &shca->ib_device;
186         event.event = event_type;
187
188         if (qp->ext_type == EQPT_SRQ) {
189                 if (!qp->ib_srq.event_handler)
190                         return;
191
192                 event.element.srq = &qp->ib_srq;
193                 qp->ib_srq.event_handler(&event, qp->ib_srq.srq_context);
194         } else {
195                 if (!qp->ib_qp.event_handler)
196                         return;
197
198                 event.element.qp = &qp->ib_qp;
199                 qp->ib_qp.event_handler(&event, qp->ib_qp.qp_context);
200         }
201 }
202
203 static void qp_event_callback(struct ehca_shca *shca, u64 eqe,
204                               enum ib_event_type event_type, int fatal)
205 {
206         struct ehca_qp *qp;
207         u32 token = EHCA_BMASK_GET(EQE_QP_TOKEN, eqe);
208
209         read_lock(&ehca_qp_idr_lock);
210         qp = idr_find(&ehca_qp_idr, token);
211         if (qp)
212                 atomic_inc(&qp->nr_events);
213         read_unlock(&ehca_qp_idr_lock);
214
215         if (!qp)
216                 return;
217
218         if (fatal)
219                 ehca_error_data(shca, qp, qp->ipz_qp_handle.handle);
220
221         dispatch_qp_event(shca, qp, fatal && qp->ext_type == EQPT_SRQ ?
222                           IB_EVENT_SRQ_ERR : event_type);
223
224         /*
225          * eHCA only processes one WQE at a time for SRQ base QPs,
226          * so the last WQE has been processed as soon as the QP enters
227          * error state.
228          */
229         if (fatal && qp->ext_type == EQPT_SRQBASE)
230                 dispatch_qp_event(shca, qp, IB_EVENT_QP_LAST_WQE_REACHED);
231
232         if (atomic_dec_and_test(&qp->nr_events))
233                 wake_up(&qp->wait_completion);
234         return;
235 }
236
237 static void cq_event_callback(struct ehca_shca *shca,
238                               u64 eqe)
239 {
240         struct ehca_cq *cq;
241         u32 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe);
242
243         read_lock(&ehca_cq_idr_lock);
244         cq = idr_find(&ehca_cq_idr, token);
245         if (cq)
246                 atomic_inc(&cq->nr_events);
247         read_unlock(&ehca_cq_idr_lock);
248
249         if (!cq)
250                 return;
251
252         ehca_error_data(shca, cq, cq->ipz_cq_handle.handle);
253
254         if (atomic_dec_and_test(&cq->nr_events))
255                 wake_up(&cq->wait_completion);
256
257         return;
258 }
259
260 static void parse_identifier(struct ehca_shca *shca, u64 eqe)
261 {
262         u8 identifier = EHCA_BMASK_GET(EQE_EE_IDENTIFIER, eqe);
263
264         switch (identifier) {
265         case 0x02: /* path migrated */
266                 qp_event_callback(shca, eqe, IB_EVENT_PATH_MIG, 0);
267                 break;
268         case 0x03: /* communication established */
269                 qp_event_callback(shca, eqe, IB_EVENT_COMM_EST, 0);
270                 break;
271         case 0x04: /* send queue drained */
272                 qp_event_callback(shca, eqe, IB_EVENT_SQ_DRAINED, 0);
273                 break;
274         case 0x05: /* QP error */
275         case 0x06: /* QP error */
276                 qp_event_callback(shca, eqe, IB_EVENT_QP_FATAL, 1);
277                 break;
278         case 0x07: /* CQ error */
279         case 0x08: /* CQ error */
280                 cq_event_callback(shca, eqe);
281                 break;
282         case 0x09: /* MRMWPTE error */
283                 ehca_err(&shca->ib_device, "MRMWPTE error.");
284                 break;
285         case 0x0A: /* port event */
286                 ehca_err(&shca->ib_device, "Port event.");
287                 break;
288         case 0x0B: /* MR access error */
289                 ehca_err(&shca->ib_device, "MR access error.");
290                 break;
291         case 0x0C: /* EQ error */
292                 ehca_err(&shca->ib_device, "EQ error.");
293                 break;
294         case 0x0D: /* P/Q_Key mismatch */
295                 ehca_err(&shca->ib_device, "P/Q_Key mismatch.");
296                 break;
297         case 0x10: /* sampling complete */
298                 ehca_err(&shca->ib_device, "Sampling complete.");
299                 break;
300         case 0x11: /* unaffiliated access error */
301                 ehca_err(&shca->ib_device, "Unaffiliated access error.");
302                 break;
303         case 0x12: /* path migrating */
304                 ehca_err(&shca->ib_device, "Path migrating.");
305                 break;
306         case 0x13: /* interface trace stopped */
307                 ehca_err(&shca->ib_device, "Interface trace stopped.");
308                 break;
309         case 0x14: /* first error capture info available */
310                 ehca_info(&shca->ib_device, "First error capture available");
311                 break;
312         case 0x15: /* SRQ limit reached */
313                 qp_event_callback(shca, eqe, IB_EVENT_SRQ_LIMIT_REACHED, 0);
314                 break;
315         default:
316                 ehca_err(&shca->ib_device, "Unknown identifier: %x on %s.",
317                          identifier, shca->ib_device.name);
318                 break;
319         }
320
321         return;
322 }
323
324 static void dispatch_port_event(struct ehca_shca *shca, int port_num,
325                                 enum ib_event_type type, const char *msg)
326 {
327         struct ib_event event;
328
329         ehca_info(&shca->ib_device, "port %d %s.", port_num, msg);
330         event.device = &shca->ib_device;
331         event.event = type;
332         event.element.port_num = port_num;
333         ib_dispatch_event(&event);
334 }
335
336 static void notify_port_conf_change(struct ehca_shca *shca, int port_num)
337 {
338         struct ehca_sma_attr  new_attr;
339         struct ehca_sma_attr *old_attr = &shca->sport[port_num - 1].saved_attr;
340
341         ehca_query_sma_attr(shca, port_num, &new_attr);
342
343         if (new_attr.sm_sl  != old_attr->sm_sl ||
344             new_attr.sm_lid != old_attr->sm_lid)
345                 dispatch_port_event(shca, port_num, IB_EVENT_SM_CHANGE,
346                                     "SM changed");
347
348         if (new_attr.lid != old_attr->lid ||
349             new_attr.lmc != old_attr->lmc)
350                 dispatch_port_event(shca, port_num, IB_EVENT_LID_CHANGE,
351                                     "LID changed");
352
353         if (new_attr.pkey_tbl_len != old_attr->pkey_tbl_len ||
354             memcmp(new_attr.pkeys, old_attr->pkeys,
355                    sizeof(u16) * new_attr.pkey_tbl_len))
356                 dispatch_port_event(shca, port_num, IB_EVENT_PKEY_CHANGE,
357                                     "P_Key changed");
358
359         *old_attr = new_attr;
360 }
361
362 /* replay modify_qp for sqps -- return 0 if all is well, 1 if AQP1 destroyed */
363 static int replay_modify_qp(struct ehca_sport *sport)
364 {
365         int aqp1_destroyed;
366         unsigned long flags;
367
368         spin_lock_irqsave(&sport->mod_sqp_lock, flags);
369
370         aqp1_destroyed = !sport->ibqp_sqp[IB_QPT_GSI];
371
372         if (sport->ibqp_sqp[IB_QPT_SMI])
373                 ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_SMI]);
374         if (!aqp1_destroyed)
375                 ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_GSI]);
376
377         spin_unlock_irqrestore(&sport->mod_sqp_lock, flags);
378
379         return aqp1_destroyed;
380 }
381
382 static void parse_ec(struct ehca_shca *shca, u64 eqe)
383 {
384         u8 ec   = EHCA_BMASK_GET(NEQE_EVENT_CODE, eqe);
385         u8 port = EHCA_BMASK_GET(NEQE_PORT_NUMBER, eqe);
386         u8 spec_event;
387         struct ehca_sport *sport = &shca->sport[port - 1];
388
389         switch (ec) {
390         case 0x30: /* port availability change */
391                 if (EHCA_BMASK_GET(NEQE_PORT_AVAILABILITY, eqe)) {
392                         /* only replay modify_qp calls in autodetect mode;
393                          * if AQP1 was destroyed, the port is already down
394                          * again and we can drop the event.
395                          */
396                         if (ehca_nr_ports < 0)
397                                 if (replay_modify_qp(sport))
398                                         break;
399
400                         sport->port_state = IB_PORT_ACTIVE;
401                         dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
402                                             "is active");
403                         ehca_query_sma_attr(shca, port, &sport->saved_attr);
404                 } else {
405                         sport->port_state = IB_PORT_DOWN;
406                         dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
407                                             "is inactive");
408                 }
409                 break;
410         case 0x31:
411                 /* port configuration change
412                  * disruptive change is caused by
413                  * LID, PKEY or SM change
414                  */
415                 if (EHCA_BMASK_GET(NEQE_DISRUPTIVE, eqe)) {
416                         ehca_warn(&shca->ib_device, "disruptive port "
417                                   "%d configuration change", port);
418
419                         sport->port_state = IB_PORT_DOWN;
420                         dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
421                                             "is inactive");
422
423                         sport->port_state = IB_PORT_ACTIVE;
424                         dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
425                                             "is active");
426                         ehca_query_sma_attr(shca, port,
427                                             &sport->saved_attr);
428                 } else
429                         notify_port_conf_change(shca, port);
430                 break;
431         case 0x32: /* adapter malfunction */
432                 ehca_err(&shca->ib_device, "Adapter malfunction.");
433                 break;
434         case 0x33:  /* trace stopped */
435                 ehca_err(&shca->ib_device, "Traced stopped.");
436                 break;
437         case 0x34: /* util async event */
438                 spec_event = EHCA_BMASK_GET(NEQE_SPECIFIC_EVENT, eqe);
439                 if (spec_event == 0x80) /* client reregister required */
440                         dispatch_port_event(shca, port,
441                                             IB_EVENT_CLIENT_REREGISTER,
442                                             "client reregister req.");
443                 else
444                         ehca_warn(&shca->ib_device, "Unknown util async "
445                                   "event %x on port %x", spec_event, port);
446                 break;
447         default:
448                 ehca_err(&shca->ib_device, "Unknown event code: %x on %s.",
449                          ec, shca->ib_device.name);
450                 break;
451         }
452
453         return;
454 }
455
456 static inline void reset_eq_pending(struct ehca_cq *cq)
457 {
458         u64 CQx_EP;
459         struct h_galpa gal = cq->galpas.kernel;
460
461         hipz_galpa_store_cq(gal, cqx_ep, 0x0);
462         CQx_EP = hipz_galpa_load(gal, CQTEMM_OFFSET(cqx_ep));
463
464         return;
465 }
466
467 irqreturn_t ehca_interrupt_neq(int irq, void *dev_id)
468 {
469         struct ehca_shca *shca = (struct ehca_shca*)dev_id;
470
471         tasklet_hi_schedule(&shca->neq.interrupt_task);
472
473         return IRQ_HANDLED;
474 }
475
476 void ehca_tasklet_neq(unsigned long data)
477 {
478         struct ehca_shca *shca = (struct ehca_shca*)data;
479         struct ehca_eqe *eqe;
480         u64 ret;
481
482         eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->neq);
483
484         while (eqe) {
485                 if (!EHCA_BMASK_GET(NEQE_COMPLETION_EVENT, eqe->entry))
486                         parse_ec(shca, eqe->entry);
487
488                 eqe = (struct ehca_eqe *)ehca_poll_eq(shca, &shca->neq);
489         }
490
491         ret = hipz_h_reset_event(shca->ipz_hca_handle,
492                                  shca->neq.ipz_eq_handle, 0xFFFFFFFFFFFFFFFFL);
493
494         if (ret != H_SUCCESS)
495                 ehca_err(&shca->ib_device, "Can't clear notification events.");
496
497         return;
498 }
499
500 irqreturn_t ehca_interrupt_eq(int irq, void *dev_id)
501 {
502         struct ehca_shca *shca = (struct ehca_shca*)dev_id;
503
504         tasklet_hi_schedule(&shca->eq.interrupt_task);
505
506         return IRQ_HANDLED;
507 }
508
509
510 static inline void process_eqe(struct ehca_shca *shca, struct ehca_eqe *eqe)
511 {
512         u64 eqe_value;
513         u32 token;
514         struct ehca_cq *cq;
515
516         eqe_value = eqe->entry;
517         ehca_dbg(&shca->ib_device, "eqe_value=%lx", eqe_value);
518         if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
519                 ehca_dbg(&shca->ib_device, "Got completion event");
520                 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
521                 read_lock(&ehca_cq_idr_lock);
522                 cq = idr_find(&ehca_cq_idr, token);
523                 if (cq)
524                         atomic_inc(&cq->nr_events);
525                 read_unlock(&ehca_cq_idr_lock);
526                 if (cq == NULL) {
527                         ehca_err(&shca->ib_device,
528                                  "Invalid eqe for non-existing cq token=%x",
529                                  token);
530                         return;
531                 }
532                 reset_eq_pending(cq);
533                 if (ehca_scaling_code)
534                         queue_comp_task(cq);
535                 else {
536                         comp_event_callback(cq);
537                         if (atomic_dec_and_test(&cq->nr_events))
538                                 wake_up(&cq->wait_completion);
539                 }
540         } else {
541                 ehca_dbg(&shca->ib_device, "Got non completion event");
542                 parse_identifier(shca, eqe_value);
543         }
544 }
545
546 void ehca_process_eq(struct ehca_shca *shca, int is_irq)
547 {
548         struct ehca_eq *eq = &shca->eq;
549         struct ehca_eqe_cache_entry *eqe_cache = eq->eqe_cache;
550         u64 eqe_value, ret;
551         unsigned long flags;
552         int eqe_cnt, i;
553         int eq_empty = 0;
554
555         spin_lock_irqsave(&eq->irq_spinlock, flags);
556         if (is_irq) {
557                 const int max_query_cnt = 100;
558                 int query_cnt = 0;
559                 int int_state = 1;
560                 do {
561                         int_state = hipz_h_query_int_state(
562                                 shca->ipz_hca_handle, eq->ist);
563                         query_cnt++;
564                         iosync();
565                 } while (int_state && query_cnt < max_query_cnt);
566                 if (unlikely((query_cnt == max_query_cnt)))
567                         ehca_dbg(&shca->ib_device, "int_state=%x query_cnt=%x",
568                                  int_state, query_cnt);
569         }
570
571         /* read out all eqes */
572         eqe_cnt = 0;
573         do {
574                 u32 token;
575                 eqe_cache[eqe_cnt].eqe =
576                         (struct ehca_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 = %ld\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 = (struct ehca_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_irqrestore(&eq->irq_spinlock, flags);
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, per_cpu_ptr(pool->cpu_comp_tasks,
831                                                   smp_processor_id()));
832         }
833
834         spin_unlock_irqrestore(&cct->task_lock, flags_cct);
835
836 }
837
838 static int __cpuinit comp_pool_callback(struct notifier_block *nfb,
839                                         unsigned long action,
840                                         void *hcpu)
841 {
842         unsigned int cpu = (unsigned long)hcpu;
843         struct ehca_cpu_comp_task *cct;
844
845         switch (action) {
846         case CPU_UP_PREPARE:
847         case CPU_UP_PREPARE_FROZEN:
848                 ehca_gen_dbg("CPU: %x (CPU_PREPARE)", cpu);
849                 if (!create_comp_task(pool, cpu)) {
850                         ehca_gen_err("Can't create comp_task for cpu: %x", cpu);
851                         return NOTIFY_BAD;
852                 }
853                 break;
854         case CPU_UP_CANCELED:
855         case CPU_UP_CANCELED_FROZEN:
856                 ehca_gen_dbg("CPU: %x (CPU_CANCELED)", cpu);
857                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
858                 kthread_bind(cct->task, cpumask_any(cpu_online_mask));
859                 destroy_comp_task(pool, cpu);
860                 break;
861         case CPU_ONLINE:
862         case CPU_ONLINE_FROZEN:
863                 ehca_gen_dbg("CPU: %x (CPU_ONLINE)", cpu);
864                 cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
865                 kthread_bind(cct->task, cpu);
866                 wake_up_process(cct->task);
867                 break;
868         case CPU_DOWN_PREPARE:
869         case CPU_DOWN_PREPARE_FROZEN:
870                 ehca_gen_dbg("CPU: %x (CPU_DOWN_PREPARE)", cpu);
871                 break;
872         case CPU_DOWN_FAILED:
873         case CPU_DOWN_FAILED_FROZEN:
874                 ehca_gen_dbg("CPU: %x (CPU_DOWN_FAILED)", cpu);
875                 break;
876         case CPU_DEAD:
877         case CPU_DEAD_FROZEN:
878                 ehca_gen_dbg("CPU: %x (CPU_DEAD)", cpu);
879                 destroy_comp_task(pool, cpu);
880                 take_over_work(pool, cpu);
881                 break;
882         }
883
884         return NOTIFY_OK;
885 }
886
887 static struct notifier_block comp_pool_callback_nb __cpuinitdata = {
888         .notifier_call  = comp_pool_callback,
889         .priority       = 0,
890 };
891
892 int ehca_create_comp_pool(void)
893 {
894         int cpu;
895         struct task_struct *task;
896
897         if (!ehca_scaling_code)
898                 return 0;
899
900         pool = kzalloc(sizeof(struct ehca_comp_pool), GFP_KERNEL);
901         if (pool == NULL)
902                 return -ENOMEM;
903
904         spin_lock_init(&pool->last_cpu_lock);
905         pool->last_cpu = cpumask_any(cpu_online_mask);
906
907         pool->cpu_comp_tasks = alloc_percpu(struct ehca_cpu_comp_task);
908         if (pool->cpu_comp_tasks == NULL) {
909                 kfree(pool);
910                 return -EINVAL;
911         }
912
913         for_each_online_cpu(cpu) {
914                 task = create_comp_task(pool, cpu);
915                 if (task) {
916                         kthread_bind(task, cpu);
917                         wake_up_process(task);
918                 }
919         }
920
921         register_hotcpu_notifier(&comp_pool_callback_nb);
922
923         printk(KERN_INFO "eHCA scaling code enabled\n");
924
925         return 0;
926 }
927
928 void ehca_destroy_comp_pool(void)
929 {
930         int i;
931
932         if (!ehca_scaling_code)
933                 return;
934
935         unregister_hotcpu_notifier(&comp_pool_callback_nb);
936
937         for_each_online_cpu(i)
938                 destroy_comp_task(pool, i);
939
940         free_percpu(pool->cpu_comp_tasks);
941         kfree(pool);
942 }