1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* |
3 | * Header file for the BFQ I/O scheduler: data structures and |
4 | * prototypes of interface functions among BFQ components. |
5 | */ |
6 | #ifndef _BFQ_H |
7 | #define _BFQ_H |
8 | |
9 | #include <linux/blktrace_api.h> |
10 | #include <linux/hrtimer.h> |
11 | |
12 | #include "blk-cgroup-rwstat.h" |
13 | |
14 | #define BFQ_IOPRIO_CLASSES 3 |
15 | #define BFQ_CL_IDLE_TIMEOUT (HZ/5) |
16 | |
17 | #define BFQ_MIN_WEIGHT 1 |
18 | #define BFQ_MAX_WEIGHT 1000 |
19 | #define BFQ_WEIGHT_CONVERSION_COEFF 10 |
20 | |
21 | #define BFQ_DEFAULT_QUEUE_IOPRIO 4 |
22 | |
23 | #define BFQ_DEFAULT_GRP_IOPRIO 0 |
24 | #define BFQ_DEFAULT_GRP_CLASS IOPRIO_CLASS_BE |
25 | |
26 | #define MAX_BFQQ_NAME_LENGTH 16 |
27 | |
28 | /* |
29 | * Soft real-time applications are extremely more latency sensitive |
30 | * than interactive ones. Over-raise the weight of the former to |
31 | * privilege them against the latter. |
32 | */ |
33 | #define BFQ_SOFTRT_WEIGHT_FACTOR 100 |
34 | |
35 | /* |
36 | * Maximum number of actuators supported. This constant is used simply |
37 | * to define the size of the static array that will contain |
38 | * per-actuator data. The current value is hopefully a good upper |
39 | * bound to the possible number of actuators of any actual drive. |
40 | */ |
41 | #define BFQ_MAX_ACTUATORS 8 |
42 | |
43 | struct bfq_entity; |
44 | |
45 | /** |
46 | * struct bfq_service_tree - per ioprio_class service tree. |
47 | * |
48 | * Each service tree represents a B-WF2Q+ scheduler on its own. Each |
49 | * ioprio_class has its own independent scheduler, and so its own |
50 | * bfq_service_tree. All the fields are protected by the queue lock |
51 | * of the containing bfqd. |
52 | */ |
53 | struct bfq_service_tree { |
54 | /* tree for active entities (i.e., those backlogged) */ |
55 | struct rb_root active; |
56 | /* tree for idle entities (i.e., not backlogged, with V < F_i)*/ |
57 | struct rb_root idle; |
58 | |
59 | /* idle entity with minimum F_i */ |
60 | struct bfq_entity *first_idle; |
61 | /* idle entity with maximum F_i */ |
62 | struct bfq_entity *last_idle; |
63 | |
64 | /* scheduler virtual time */ |
65 | u64 vtime; |
66 | /* scheduler weight sum; active and idle entities contribute to it */ |
67 | unsigned long wsum; |
68 | }; |
69 | |
70 | /** |
71 | * struct bfq_sched_data - multi-class scheduler. |
72 | * |
73 | * bfq_sched_data is the basic scheduler queue. It supports three |
74 | * ioprio_classes, and can be used either as a toplevel queue or as an |
75 | * intermediate queue in a hierarchical setup. |
76 | * |
77 | * The supported ioprio_classes are the same as in CFQ, in descending |
78 | * priority order, IOPRIO_CLASS_RT, IOPRIO_CLASS_BE, IOPRIO_CLASS_IDLE. |
79 | * Requests from higher priority queues are served before all the |
80 | * requests from lower priority queues; among requests of the same |
81 | * queue requests are served according to B-WF2Q+. |
82 | * |
83 | * The schedule is implemented by the service trees, plus the field |
84 | * @next_in_service, which points to the entity on the active trees |
85 | * that will be served next, if 1) no changes in the schedule occurs |
86 | * before the current in-service entity is expired, 2) the in-service |
87 | * queue becomes idle when it expires, and 3) if the entity pointed by |
88 | * in_service_entity is not a queue, then the in-service child entity |
89 | * of the entity pointed by in_service_entity becomes idle on |
90 | * expiration. This peculiar definition allows for the following |
91 | * optimization, not yet exploited: while a given entity is still in |
92 | * service, we already know which is the best candidate for next |
93 | * service among the other active entities in the same parent |
94 | * entity. We can then quickly compare the timestamps of the |
95 | * in-service entity with those of such best candidate. |
96 | * |
97 | * All fields are protected by the lock of the containing bfqd. |
98 | */ |
99 | struct bfq_sched_data { |
100 | /* entity in service */ |
101 | struct bfq_entity *in_service_entity; |
102 | /* head-of-line entity (see comments above) */ |
103 | struct bfq_entity *next_in_service; |
104 | /* array of service trees, one per ioprio_class */ |
105 | struct bfq_service_tree service_tree[BFQ_IOPRIO_CLASSES]; |
106 | /* last time CLASS_IDLE was served */ |
107 | unsigned long bfq_class_idle_last_service; |
108 | |
109 | }; |
110 | |
111 | /** |
112 | * struct bfq_weight_counter - counter of the number of all active queues |
113 | * with a given weight. |
114 | */ |
115 | struct bfq_weight_counter { |
116 | unsigned int weight; /* weight of the queues this counter refers to */ |
117 | unsigned int num_active; /* nr of active queues with this weight */ |
118 | /* |
119 | * Weights tree member (see bfq_data's @queue_weights_tree) |
120 | */ |
121 | struct rb_node weights_node; |
122 | }; |
123 | |
124 | /** |
125 | * struct bfq_entity - schedulable entity. |
126 | * |
127 | * A bfq_entity is used to represent either a bfq_queue (leaf node in the |
128 | * cgroup hierarchy) or a bfq_group into the upper level scheduler. Each |
129 | * entity belongs to the sched_data of the parent group in the cgroup |
130 | * hierarchy. Non-leaf entities have also their own sched_data, stored |
131 | * in @my_sched_data. |
132 | * |
133 | * Each entity stores independently its priority values; this would |
134 | * allow different weights on different devices, but this |
135 | * functionality is not exported to userspace by now. Priorities and |
136 | * weights are updated lazily, first storing the new values into the |
137 | * new_* fields, then setting the @prio_changed flag. As soon as |
138 | * there is a transition in the entity state that allows the priority |
139 | * update to take place the effective and the requested priority |
140 | * values are synchronized. |
141 | * |
142 | * Unless cgroups are used, the weight value is calculated from the |
143 | * ioprio to export the same interface as CFQ. When dealing with |
144 | * "well-behaved" queues (i.e., queues that do not spend too much |
145 | * time to consume their budget and have true sequential behavior, and |
146 | * when there are no external factors breaking anticipation) the |
147 | * relative weights at each level of the cgroups hierarchy should be |
148 | * guaranteed. All the fields are protected by the queue lock of the |
149 | * containing bfqd. |
150 | */ |
151 | struct bfq_entity { |
152 | /* service_tree member */ |
153 | struct rb_node rb_node; |
154 | |
155 | /* |
156 | * Flag, true if the entity is on a tree (either the active or |
157 | * the idle one of its service_tree) or is in service. |
158 | */ |
159 | bool on_st_or_in_serv; |
160 | |
161 | /* B-WF2Q+ start and finish timestamps [sectors/weight] */ |
162 | u64 start, finish; |
163 | |
164 | /* tree the entity is enqueued into; %NULL if not on a tree */ |
165 | struct rb_root *tree; |
166 | |
167 | /* |
168 | * minimum start time of the (active) subtree rooted at this |
169 | * entity; used for O(log N) lookups into active trees |
170 | */ |
171 | u64 min_start; |
172 | |
173 | /* amount of service received during the last service slot */ |
174 | int service; |
175 | |
176 | /* budget, used also to calculate F_i: F_i = S_i + @budget / @weight */ |
177 | int budget; |
178 | |
179 | /* Number of requests allocated in the subtree of this entity */ |
180 | int allocated; |
181 | |
182 | /* device weight, if non-zero, it overrides the default weight of |
183 | * bfq_group_data */ |
184 | int dev_weight; |
185 | /* weight of the queue */ |
186 | int weight; |
187 | /* next weight if a change is in progress */ |
188 | int new_weight; |
189 | |
190 | /* original weight, used to implement weight boosting */ |
191 | int orig_weight; |
192 | |
193 | /* parent entity, for hierarchical scheduling */ |
194 | struct bfq_entity *parent; |
195 | |
196 | /* |
197 | * For non-leaf nodes in the hierarchy, the associated |
198 | * scheduler queue, %NULL on leaf nodes. |
199 | */ |
200 | struct bfq_sched_data *my_sched_data; |
201 | /* the scheduler queue this entity belongs to */ |
202 | struct bfq_sched_data *sched_data; |
203 | |
204 | /* flag, set to request a weight, ioprio or ioprio_class change */ |
205 | int prio_changed; |
206 | |
207 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
208 | /* flag, set if the entity is counted in groups_with_pending_reqs */ |
209 | bool in_groups_with_pending_reqs; |
210 | #endif |
211 | |
212 | /* last child queue of entity created (for non-leaf entities) */ |
213 | struct bfq_queue *last_bfqq_created; |
214 | }; |
215 | |
216 | struct bfq_group; |
217 | |
218 | /** |
219 | * struct bfq_ttime - per process thinktime stats. |
220 | */ |
221 | struct bfq_ttime { |
222 | /* completion time of the last request */ |
223 | u64 last_end_request; |
224 | |
225 | /* total process thinktime */ |
226 | u64 ttime_total; |
227 | /* number of thinktime samples */ |
228 | unsigned long ttime_samples; |
229 | /* average process thinktime */ |
230 | u64 ttime_mean; |
231 | }; |
232 | |
233 | /** |
234 | * struct bfq_queue - leaf schedulable entity. |
235 | * |
236 | * A bfq_queue is a leaf request queue; it can be associated with an |
237 | * io_context or more, if it is async or shared between cooperating |
238 | * processes. Besides, it contains I/O requests for only one actuator |
239 | * (an io_context is associated with a different bfq_queue for each |
240 | * actuator it generates I/O for). @cgroup holds a reference to the |
241 | * cgroup, to be sure that it does not disappear while a bfqq still |
242 | * references it (mostly to avoid races between request issuing and |
243 | * task migration followed by cgroup destruction). All the fields are |
244 | * protected by the queue lock of the containing bfqd. |
245 | */ |
246 | struct bfq_queue { |
247 | /* reference counter */ |
248 | int ref; |
249 | /* counter of references from other queues for delayed stable merge */ |
250 | int stable_ref; |
251 | /* parent bfq_data */ |
252 | struct bfq_data *bfqd; |
253 | |
254 | /* current ioprio and ioprio class */ |
255 | unsigned short ioprio, ioprio_class; |
256 | /* next ioprio and ioprio class if a change is in progress */ |
257 | unsigned short new_ioprio, new_ioprio_class; |
258 | |
259 | /* last total-service-time sample, see bfq_update_inject_limit() */ |
260 | u64 last_serv_time_ns; |
261 | /* limit for request injection */ |
262 | unsigned int inject_limit; |
263 | /* last time the inject limit has been decreased, in jiffies */ |
264 | unsigned long decrease_time_jif; |
265 | |
266 | /* |
267 | * Shared bfq_queue if queue is cooperating with one or more |
268 | * other queues. |
269 | */ |
270 | struct bfq_queue *new_bfqq; |
271 | /* request-position tree member (see bfq_group's @rq_pos_tree) */ |
272 | struct rb_node pos_node; |
273 | /* request-position tree root (see bfq_group's @rq_pos_tree) */ |
274 | struct rb_root *pos_root; |
275 | |
276 | /* sorted list of pending requests */ |
277 | struct rb_root sort_list; |
278 | /* if fifo isn't expired, next request to serve */ |
279 | struct request *next_rq; |
280 | /* number of sync and async requests queued */ |
281 | int queued[2]; |
282 | /* number of pending metadata requests */ |
283 | int meta_pending; |
284 | /* fifo list of requests in sort_list */ |
285 | struct list_head fifo; |
286 | |
287 | /* entity representing this queue in the scheduler */ |
288 | struct bfq_entity entity; |
289 | |
290 | /* pointer to the weight counter associated with this entity */ |
291 | struct bfq_weight_counter *weight_counter; |
292 | |
293 | /* maximum budget allowed from the feedback mechanism */ |
294 | int max_budget; |
295 | /* budget expiration (in jiffies) */ |
296 | unsigned long budget_timeout; |
297 | |
298 | /* number of requests on the dispatch list or inside driver */ |
299 | int dispatched; |
300 | |
301 | /* status flags */ |
302 | unsigned long flags; |
303 | |
304 | /* node for active/idle bfqq list inside parent bfqd */ |
305 | struct list_head bfqq_list; |
306 | |
307 | /* associated @bfq_ttime struct */ |
308 | struct bfq_ttime ttime; |
309 | |
310 | /* when bfqq started to do I/O within the last observation window */ |
311 | u64 io_start_time; |
312 | /* how long bfqq has remained empty during the last observ. window */ |
313 | u64 tot_idle_time; |
314 | |
315 | /* bit vector: a 1 for each seeky requests in history */ |
316 | u32 seek_history; |
317 | |
318 | /* node for the device's burst list */ |
319 | struct hlist_node burst_list_node; |
320 | |
321 | /* position of the last request enqueued */ |
322 | sector_t last_request_pos; |
323 | |
324 | /* Number of consecutive pairs of request completion and |
325 | * arrival, such that the queue becomes idle after the |
326 | * completion, but the next request arrives within an idle |
327 | * time slice; used only if the queue's IO_bound flag has been |
328 | * cleared. |
329 | */ |
330 | unsigned int requests_within_timer; |
331 | |
332 | /* pid of the process owning the queue, used for logging purposes */ |
333 | pid_t pid; |
334 | |
335 | /* |
336 | * Pointer to the bfq_io_cq owning the bfq_queue, set to %NULL |
337 | * if the queue is shared. |
338 | */ |
339 | struct bfq_io_cq *bic; |
340 | |
341 | /* current maximum weight-raising time for this queue */ |
342 | unsigned long wr_cur_max_time; |
343 | /* |
344 | * Minimum time instant such that, only if a new request is |
345 | * enqueued after this time instant in an idle @bfq_queue with |
346 | * no outstanding requests, then the task associated with the |
347 | * queue it is deemed as soft real-time (see the comments on |
348 | * the function bfq_bfqq_softrt_next_start()) |
349 | */ |
350 | unsigned long soft_rt_next_start; |
351 | /* |
352 | * Start time of the current weight-raising period if |
353 | * the @bfq-queue is being weight-raised, otherwise |
354 | * finish time of the last weight-raising period. |
355 | */ |
356 | unsigned long last_wr_start_finish; |
357 | /* factor by which the weight of this queue is multiplied */ |
358 | unsigned int wr_coeff; |
359 | /* |
360 | * Time of the last transition of the @bfq_queue from idle to |
361 | * backlogged. |
362 | */ |
363 | unsigned long last_idle_bklogged; |
364 | /* |
365 | * Cumulative service received from the @bfq_queue since the |
366 | * last transition from idle to backlogged. |
367 | */ |
368 | unsigned long service_from_backlogged; |
369 | /* |
370 | * Cumulative service received from the @bfq_queue since its |
371 | * last transition to weight-raised state. |
372 | */ |
373 | unsigned long service_from_wr; |
374 | |
375 | /* |
376 | * Value of wr start time when switching to soft rt |
377 | */ |
378 | unsigned long wr_start_at_switch_to_srt; |
379 | |
380 | unsigned long split_time; /* time of last split */ |
381 | |
382 | unsigned long first_IO_time; /* time of first I/O for this queue */ |
383 | unsigned long creation_time; /* when this queue is created */ |
384 | |
385 | /* |
386 | * Pointer to the waker queue for this queue, i.e., to the |
387 | * queue Q such that this queue happens to get new I/O right |
388 | * after some I/O request of Q is completed. For details, see |
389 | * the comments on the choice of the queue for injection in |
390 | * bfq_select_queue(). |
391 | */ |
392 | struct bfq_queue *waker_bfqq; |
393 | /* pointer to the curr. tentative waker queue, see bfq_check_waker() */ |
394 | struct bfq_queue *tentative_waker_bfqq; |
395 | /* number of times the same tentative waker has been detected */ |
396 | unsigned int num_waker_detections; |
397 | /* time when we started considering this waker */ |
398 | u64 waker_detection_started; |
399 | |
400 | /* node for woken_list, see below */ |
401 | struct hlist_node woken_list_node; |
402 | /* |
403 | * Head of the list of the woken queues for this queue, i.e., |
404 | * of the list of the queues for which this queue is a waker |
405 | * queue. This list is used to reset the waker_bfqq pointer in |
406 | * the woken queues when this queue exits. |
407 | */ |
408 | struct hlist_head woken_list; |
409 | |
410 | /* index of the actuator this queue is associated with */ |
411 | unsigned int actuator_idx; |
412 | }; |
413 | |
414 | /** |
415 | * struct bfq_data - bfqq data unique and persistent for associated bfq_io_cq |
416 | */ |
417 | struct bfq_iocq_bfqq_data { |
418 | /* |
419 | * Snapshot of the has_short_time flag before merging; taken |
420 | * to remember its values while the queue is merged, so as to |
421 | * be able to restore it in case of split. |
422 | */ |
423 | bool saved_has_short_ttime; |
424 | /* |
425 | * Same purpose as the previous two fields for the I/O bound |
426 | * classification of a queue. |
427 | */ |
428 | bool saved_IO_bound; |
429 | |
430 | u64 saved_io_start_time; |
431 | u64 saved_tot_idle_time; |
432 | |
433 | /* |
434 | * Same purpose as the previous fields for the values of the |
435 | * field keeping the queue's belonging to a large burst |
436 | */ |
437 | bool saved_in_large_burst; |
438 | /* |
439 | * True if the queue belonged to a burst list before its merge |
440 | * with another cooperating queue. |
441 | */ |
442 | bool was_in_burst_list; |
443 | |
444 | /* |
445 | * Save the weight when a merge occurs, to be able |
446 | * to restore it in case of split. If the weight is not |
447 | * correctly resumed when the queue is recycled, |
448 | * then the weight of the recycled queue could differ |
449 | * from the weight of the original queue. |
450 | */ |
451 | unsigned int saved_weight; |
452 | |
453 | /* |
454 | * Similar to previous fields: save wr information. |
455 | */ |
456 | unsigned long saved_wr_coeff; |
457 | unsigned long saved_last_wr_start_finish; |
458 | unsigned long saved_service_from_wr; |
459 | unsigned long saved_wr_start_at_switch_to_srt; |
460 | unsigned int saved_wr_cur_max_time; |
461 | struct bfq_ttime saved_ttime; |
462 | |
463 | /* Save also injection state */ |
464 | u64 saved_last_serv_time_ns; |
465 | unsigned int saved_inject_limit; |
466 | unsigned long saved_decrease_time_jif; |
467 | |
468 | /* candidate queue for a stable merge (due to close creation time) */ |
469 | struct bfq_queue *stable_merge_bfqq; |
470 | |
471 | bool stably_merged; /* non splittable if true */ |
472 | }; |
473 | |
474 | /** |
475 | * struct bfq_io_cq - per (request_queue, io_context) structure. |
476 | */ |
477 | struct bfq_io_cq { |
478 | /* associated io_cq structure */ |
479 | struct io_cq icq; /* must be the first member */ |
480 | /* |
481 | * Matrix of associated process queues: first row for async |
482 | * queues, second row sync queues. Each row contains one |
483 | * column for each actuator. An I/O request generated by the |
484 | * process is inserted into the queue pointed by bfqq[i][j] if |
485 | * the request is to be served by the j-th actuator of the |
486 | * drive, where i==0 or i==1, depending on whether the request |
487 | * is async or sync. So there is a distinct queue for each |
488 | * actuator. |
489 | */ |
490 | struct bfq_queue *bfqq[2][BFQ_MAX_ACTUATORS]; |
491 | /* per (request_queue, blkcg) ioprio */ |
492 | int ioprio; |
493 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
494 | uint64_t blkcg_serial_nr; /* the current blkcg serial */ |
495 | #endif |
496 | |
497 | /* |
498 | * Persistent data for associated synchronous process queues |
499 | * (one queue per actuator, see field bfqq above). In |
500 | * particular, each of these queues may undergo a merge. |
501 | */ |
502 | struct bfq_iocq_bfqq_data bfqq_data[BFQ_MAX_ACTUATORS]; |
503 | |
504 | unsigned int requests; /* Number of requests this process has in flight */ |
505 | }; |
506 | |
507 | /** |
508 | * struct bfq_data - per-device data structure. |
509 | * |
510 | * All the fields are protected by @lock. |
511 | */ |
512 | struct bfq_data { |
513 | /* device request queue */ |
514 | struct request_queue *queue; |
515 | /* dispatch queue */ |
516 | struct list_head dispatch; |
517 | |
518 | /* root bfq_group for the device */ |
519 | struct bfq_group *root_group; |
520 | |
521 | /* |
522 | * rbtree of weight counters of @bfq_queues, sorted by |
523 | * weight. Used to keep track of whether all @bfq_queues have |
524 | * the same weight. The tree contains one counter for each |
525 | * distinct weight associated to some active and not |
526 | * weight-raised @bfq_queue (see the comments to the functions |
527 | * bfq_weights_tree_[add|remove] for further details). |
528 | */ |
529 | struct rb_root_cached queue_weights_tree; |
530 | |
531 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
532 | /* |
533 | * Number of groups with at least one process that |
534 | * has at least one request waiting for completion. Note that |
535 | * this accounts for also requests already dispatched, but not |
536 | * yet completed. Therefore this number of groups may differ |
537 | * (be larger) than the number of active groups, as a group is |
538 | * considered active only if its corresponding entity has |
539 | * queues with at least one request queued. This |
540 | * number is used to decide whether a scenario is symmetric. |
541 | * For a detailed explanation see comments on the computation |
542 | * of the variable asymmetric_scenario in the function |
543 | * bfq_better_to_idle(). |
544 | * |
545 | * However, it is hard to compute this number exactly, for |
546 | * groups with multiple processes. Consider a group |
547 | * that is inactive, i.e., that has no process with |
548 | * pending I/O inside BFQ queues. Then suppose that |
549 | * num_groups_with_pending_reqs is still accounting for this |
550 | * group, because the group has processes with some |
551 | * I/O request still in flight. num_groups_with_pending_reqs |
552 | * should be decremented when the in-flight request of the |
553 | * last process is finally completed (assuming that |
554 | * nothing else has changed for the group in the meantime, in |
555 | * terms of composition of the group and active/inactive state of child |
556 | * groups and processes). To accomplish this, an additional |
557 | * pending-request counter must be added to entities, and must |
558 | * be updated correctly. To avoid this additional field and operations, |
559 | * we resort to the following tradeoff between simplicity and |
560 | * accuracy: for an inactive group that is still counted in |
561 | * num_groups_with_pending_reqs, we decrement |
562 | * num_groups_with_pending_reqs when the first |
563 | * process of the group remains with no request waiting for |
564 | * completion. |
565 | * |
566 | * Even this simpler decrement strategy requires a little |
567 | * carefulness: to avoid multiple decrements, we flag a group, |
568 | * more precisely an entity representing a group, as still |
569 | * counted in num_groups_with_pending_reqs when it becomes |
570 | * inactive. Then, when the first queue of the |
571 | * entity remains with no request waiting for completion, |
572 | * num_groups_with_pending_reqs is decremented, and this flag |
573 | * is reset. After this flag is reset for the entity, |
574 | * num_groups_with_pending_reqs won't be decremented any |
575 | * longer in case a new queue of the entity remains |
576 | * with no request waiting for completion. |
577 | */ |
578 | unsigned int num_groups_with_pending_reqs; |
579 | #endif |
580 | |
581 | /* |
582 | * Per-class (RT, BE, IDLE) number of bfq_queues containing |
583 | * requests (including the queue in service, even if it is |
584 | * idling). |
585 | */ |
586 | unsigned int busy_queues[3]; |
587 | /* number of weight-raised busy @bfq_queues */ |
588 | int wr_busy_queues; |
589 | /* number of queued requests */ |
590 | int queued; |
591 | /* number of requests dispatched and waiting for completion */ |
592 | int tot_rq_in_driver; |
593 | /* |
594 | * number of requests dispatched and waiting for completion |
595 | * for each actuator |
596 | */ |
597 | int rq_in_driver[BFQ_MAX_ACTUATORS]; |
598 | |
599 | /* true if the device is non rotational and performs queueing */ |
600 | bool nonrot_with_queueing; |
601 | |
602 | /* |
603 | * Maximum number of requests in driver in the last |
604 | * @hw_tag_samples completed requests. |
605 | */ |
606 | int max_rq_in_driver; |
607 | /* number of samples used to calculate hw_tag */ |
608 | int hw_tag_samples; |
609 | /* flag set to one if the driver is showing a queueing behavior */ |
610 | int hw_tag; |
611 | |
612 | /* number of budgets assigned */ |
613 | int budgets_assigned; |
614 | |
615 | /* |
616 | * Timer set when idling (waiting) for the next request from |
617 | * the queue in service. |
618 | */ |
619 | struct hrtimer idle_slice_timer; |
620 | |
621 | /* bfq_queue in service */ |
622 | struct bfq_queue *in_service_queue; |
623 | |
624 | /* on-disk position of the last served request */ |
625 | sector_t last_position; |
626 | |
627 | /* position of the last served request for the in-service queue */ |
628 | sector_t in_serv_last_pos; |
629 | |
630 | /* time of last request completion (ns) */ |
631 | u64 last_completion; |
632 | |
633 | /* bfqq owning the last completed rq */ |
634 | struct bfq_queue *last_completed_rq_bfqq; |
635 | |
636 | /* last bfqq created, among those in the root group */ |
637 | struct bfq_queue *last_bfqq_created; |
638 | |
639 | /* time of last transition from empty to non-empty (ns) */ |
640 | u64 last_empty_occupied_ns; |
641 | |
642 | /* |
643 | * Flag set to activate the sampling of the total service time |
644 | * of a just-arrived first I/O request (see |
645 | * bfq_update_inject_limit()). This will cause the setting of |
646 | * waited_rq when the request is finally dispatched. |
647 | */ |
648 | bool wait_dispatch; |
649 | /* |
650 | * If set, then bfq_update_inject_limit() is invoked when |
651 | * waited_rq is eventually completed. |
652 | */ |
653 | struct request *waited_rq; |
654 | /* |
655 | * True if some request has been injected during the last service hole. |
656 | */ |
657 | bool rqs_injected; |
658 | |
659 | /* time of first rq dispatch in current observation interval (ns) */ |
660 | u64 first_dispatch; |
661 | /* time of last rq dispatch in current observation interval (ns) */ |
662 | u64 last_dispatch; |
663 | |
664 | /* beginning of the last budget */ |
665 | ktime_t last_budget_start; |
666 | /* beginning of the last idle slice */ |
667 | ktime_t last_idling_start; |
668 | unsigned long last_idling_start_jiffies; |
669 | |
670 | /* number of samples in current observation interval */ |
671 | int peak_rate_samples; |
672 | /* num of samples of seq dispatches in current observation interval */ |
673 | u32 sequential_samples; |
674 | /* total num of sectors transferred in current observation interval */ |
675 | u64 tot_sectors_dispatched; |
676 | /* max rq size seen during current observation interval (sectors) */ |
677 | u32 last_rq_max_size; |
678 | /* time elapsed from first dispatch in current observ. interval (us) */ |
679 | u64 delta_from_first; |
680 | /* |
681 | * Current estimate of the device peak rate, measured in |
682 | * [(sectors/usec) / 2^BFQ_RATE_SHIFT]. The left-shift by |
683 | * BFQ_RATE_SHIFT is performed to increase precision in |
684 | * fixed-point calculations. |
685 | */ |
686 | u32 peak_rate; |
687 | |
688 | /* maximum budget allotted to a bfq_queue before rescheduling */ |
689 | int bfq_max_budget; |
690 | |
691 | /* |
692 | * List of all the bfq_queues active for a specific actuator |
693 | * on the device. Keeping active queues separate on a |
694 | * per-actuator basis helps implementing per-actuator |
695 | * injection more efficiently. |
696 | */ |
697 | struct list_head active_list[BFQ_MAX_ACTUATORS]; |
698 | /* list of all the bfq_queues idle on the device */ |
699 | struct list_head idle_list; |
700 | |
701 | /* |
702 | * Timeout for async/sync requests; when it fires, requests |
703 | * are served in fifo order. |
704 | */ |
705 | u64 bfq_fifo_expire[2]; |
706 | /* weight of backward seeks wrt forward ones */ |
707 | unsigned int bfq_back_penalty; |
708 | /* maximum allowed backward seek */ |
709 | unsigned int bfq_back_max; |
710 | /* maximum idling time */ |
711 | u32 bfq_slice_idle; |
712 | |
713 | /* user-configured max budget value (0 for auto-tuning) */ |
714 | int bfq_user_max_budget; |
715 | /* |
716 | * Timeout for bfq_queues to consume their budget; used to |
717 | * prevent seeky queues from imposing long latencies to |
718 | * sequential or quasi-sequential ones (this also implies that |
719 | * seeky queues cannot receive guarantees in the service |
720 | * domain; after a timeout they are charged for the time they |
721 | * have been in service, to preserve fairness among them, but |
722 | * without service-domain guarantees). |
723 | */ |
724 | unsigned int bfq_timeout; |
725 | |
726 | /* |
727 | * Force device idling whenever needed to provide accurate |
728 | * service guarantees, without caring about throughput |
729 | * issues. CAVEAT: this may even increase latencies, in case |
730 | * of useless idling for processes that did stop doing I/O. |
731 | */ |
732 | bool strict_guarantees; |
733 | |
734 | /* |
735 | * Last time at which a queue entered the current burst of |
736 | * queues being activated shortly after each other; for more |
737 | * details about this and the following parameters related to |
738 | * a burst of activations, see the comments on the function |
739 | * bfq_handle_burst. |
740 | */ |
741 | unsigned long last_ins_in_burst; |
742 | /* |
743 | * Reference time interval used to decide whether a queue has |
744 | * been activated shortly after @last_ins_in_burst. |
745 | */ |
746 | unsigned long bfq_burst_interval; |
747 | /* number of queues in the current burst of queue activations */ |
748 | int burst_size; |
749 | |
750 | /* common parent entity for the queues in the burst */ |
751 | struct bfq_entity *burst_parent_entity; |
752 | /* Maximum burst size above which the current queue-activation |
753 | * burst is deemed as 'large'. |
754 | */ |
755 | unsigned long bfq_large_burst_thresh; |
756 | /* true if a large queue-activation burst is in progress */ |
757 | bool large_burst; |
758 | /* |
759 | * Head of the burst list (as for the above fields, more |
760 | * details in the comments on the function bfq_handle_burst). |
761 | */ |
762 | struct hlist_head burst_list; |
763 | |
764 | /* if set to true, low-latency heuristics are enabled */ |
765 | bool low_latency; |
766 | /* |
767 | * Maximum factor by which the weight of a weight-raised queue |
768 | * is multiplied. |
769 | */ |
770 | unsigned int bfq_wr_coeff; |
771 | |
772 | /* Maximum weight-raising duration for soft real-time processes */ |
773 | unsigned int bfq_wr_rt_max_time; |
774 | /* |
775 | * Minimum idle period after which weight-raising may be |
776 | * reactivated for a queue (in jiffies). |
777 | */ |
778 | unsigned int bfq_wr_min_idle_time; |
779 | /* |
780 | * Minimum period between request arrivals after which |
781 | * weight-raising may be reactivated for an already busy async |
782 | * queue (in jiffies). |
783 | */ |
784 | unsigned long bfq_wr_min_inter_arr_async; |
785 | |
786 | /* Max service-rate for a soft real-time queue, in sectors/sec */ |
787 | unsigned int bfq_wr_max_softrt_rate; |
788 | /* |
789 | * Cached value of the product ref_rate*ref_wr_duration, used |
790 | * for computing the maximum duration of weight raising |
791 | * automatically. |
792 | */ |
793 | u64 rate_dur_prod; |
794 | |
795 | /* fallback dummy bfqq for extreme OOM conditions */ |
796 | struct bfq_queue oom_bfqq; |
797 | |
798 | spinlock_t lock; |
799 | |
800 | /* |
801 | * bic associated with the task issuing current bio for |
802 | * merging. This and the next field are used as a support to |
803 | * be able to perform the bic lookup, needed by bio-merge |
804 | * functions, before the scheduler lock is taken, and thus |
805 | * avoid taking the request-queue lock while the scheduler |
806 | * lock is being held. |
807 | */ |
808 | struct bfq_io_cq *bio_bic; |
809 | /* bfqq associated with the task issuing current bio for merging */ |
810 | struct bfq_queue *bio_bfqq; |
811 | |
812 | /* |
813 | * Depth limits used in bfq_limit_depth (see comments on the |
814 | * function) |
815 | */ |
816 | unsigned int word_depths[2][2]; |
817 | unsigned int full_depth_shift; |
818 | |
819 | /* |
820 | * Number of independent actuators. This is equal to 1 in |
821 | * case of single-actuator drives. |
822 | */ |
823 | unsigned int num_actuators; |
824 | /* |
825 | * Disk independent access ranges for each actuator |
826 | * in this device. |
827 | */ |
828 | sector_t sector[BFQ_MAX_ACTUATORS]; |
829 | sector_t nr_sectors[BFQ_MAX_ACTUATORS]; |
830 | struct blk_independent_access_range ia_ranges[BFQ_MAX_ACTUATORS]; |
831 | |
832 | /* |
833 | * If the number of I/O requests queued in the device for a |
834 | * given actuator is below next threshold, then the actuator |
835 | * is deemed as underutilized. If this condition is found to |
836 | * hold for some actuator upon a dispatch, but (i) the |
837 | * in-service queue does not contain I/O for that actuator, |
838 | * while (ii) some other queue does contain I/O for that |
839 | * actuator, then the head I/O request of the latter queue is |
840 | * returned (injected), instead of the head request of the |
841 | * currently in-service queue. |
842 | * |
843 | * We set the threshold, empirically, to the minimum possible |
844 | * value for which an actuator is fully utilized, or close to |
845 | * be fully utilized. By doing so, injected I/O 'steals' as |
846 | * few drive-queue slots as possibile to the in-service |
847 | * queue. This reduces as much as possible the probability |
848 | * that the service of I/O from the in-service bfq_queue gets |
849 | * delayed because of slot exhaustion, i.e., because all the |
850 | * slots of the drive queue are filled with I/O injected from |
851 | * other queues (NCQ provides for 32 slots). |
852 | */ |
853 | unsigned int actuator_load_threshold; |
854 | }; |
855 | |
856 | enum bfqq_state_flags { |
857 | BFQQF_just_created = 0, /* queue just allocated */ |
858 | BFQQF_busy, /* has requests or is in service */ |
859 | BFQQF_wait_request, /* waiting for a request */ |
860 | BFQQF_non_blocking_wait_rq, /* |
861 | * waiting for a request |
862 | * without idling the device |
863 | */ |
864 | BFQQF_fifo_expire, /* FIFO checked in this slice */ |
865 | BFQQF_has_short_ttime, /* queue has a short think time */ |
866 | BFQQF_sync, /* synchronous queue */ |
867 | BFQQF_IO_bound, /* |
868 | * bfqq has timed-out at least once |
869 | * having consumed at most 2/10 of |
870 | * its budget |
871 | */ |
872 | BFQQF_in_large_burst, /* |
873 | * bfqq activated in a large burst, |
874 | * see comments to bfq_handle_burst. |
875 | */ |
876 | BFQQF_softrt_update, /* |
877 | * may need softrt-next-start |
878 | * update |
879 | */ |
880 | BFQQF_coop, /* bfqq is shared */ |
881 | BFQQF_split_coop, /* shared bfqq will be split */ |
882 | }; |
883 | |
884 | #define BFQ_BFQQ_FNS(name) \ |
885 | void bfq_mark_bfqq_##name(struct bfq_queue *bfqq); \ |
886 | void bfq_clear_bfqq_##name(struct bfq_queue *bfqq); \ |
887 | int bfq_bfqq_##name(const struct bfq_queue *bfqq); |
888 | |
889 | BFQ_BFQQ_FNS(just_created); |
890 | BFQ_BFQQ_FNS(busy); |
891 | BFQ_BFQQ_FNS(wait_request); |
892 | BFQ_BFQQ_FNS(non_blocking_wait_rq); |
893 | BFQ_BFQQ_FNS(fifo_expire); |
894 | BFQ_BFQQ_FNS(has_short_ttime); |
895 | BFQ_BFQQ_FNS(sync); |
896 | BFQ_BFQQ_FNS(IO_bound); |
897 | BFQ_BFQQ_FNS(in_large_burst); |
898 | BFQ_BFQQ_FNS(coop); |
899 | BFQ_BFQQ_FNS(split_coop); |
900 | BFQ_BFQQ_FNS(softrt_update); |
901 | #undef BFQ_BFQQ_FNS |
902 | |
903 | /* Expiration reasons. */ |
904 | enum bfqq_expiration { |
905 | BFQQE_TOO_IDLE = 0, /* |
906 | * queue has been idling for |
907 | * too long |
908 | */ |
909 | BFQQE_BUDGET_TIMEOUT, /* budget took too long to be used */ |
910 | BFQQE_BUDGET_EXHAUSTED, /* budget consumed */ |
911 | BFQQE_NO_MORE_REQUESTS, /* the queue has no more requests */ |
912 | BFQQE_PREEMPTED /* preemption in progress */ |
913 | }; |
914 | |
915 | struct bfq_stat { |
916 | struct percpu_counter cpu_cnt; |
917 | atomic64_t aux_cnt; |
918 | }; |
919 | |
920 | struct bfqg_stats { |
921 | /* basic stats */ |
922 | struct blkg_rwstat bytes; |
923 | struct blkg_rwstat ios; |
924 | #ifdef CONFIG_BFQ_CGROUP_DEBUG |
925 | /* number of ios merged */ |
926 | struct blkg_rwstat merged; |
927 | /* total time spent on device in ns, may not be accurate w/ queueing */ |
928 | struct blkg_rwstat service_time; |
929 | /* total time spent waiting in scheduler queue in ns */ |
930 | struct blkg_rwstat wait_time; |
931 | /* number of IOs queued up */ |
932 | struct blkg_rwstat queued; |
933 | /* total disk time and nr sectors dispatched by this group */ |
934 | struct bfq_stat time; |
935 | /* sum of number of ios queued across all samples */ |
936 | struct bfq_stat avg_queue_size_sum; |
937 | /* count of samples taken for average */ |
938 | struct bfq_stat avg_queue_size_samples; |
939 | /* how many times this group has been removed from service tree */ |
940 | struct bfq_stat dequeue; |
941 | /* total time spent waiting for it to be assigned a timeslice. */ |
942 | struct bfq_stat group_wait_time; |
943 | /* time spent idling for this blkcg_gq */ |
944 | struct bfq_stat idle_time; |
945 | /* total time with empty current active q with other requests queued */ |
946 | struct bfq_stat empty_time; |
947 | /* fields after this shouldn't be cleared on stat reset */ |
948 | u64 start_group_wait_time; |
949 | u64 start_idle_time; |
950 | u64 start_empty_time; |
951 | uint16_t flags; |
952 | #endif /* CONFIG_BFQ_CGROUP_DEBUG */ |
953 | }; |
954 | |
955 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
956 | |
957 | /* |
958 | * struct bfq_group_data - per-blkcg storage for the blkio subsystem. |
959 | * |
960 | * @ps: @blkcg_policy_storage that this structure inherits |
961 | * @weight: weight of the bfq_group |
962 | */ |
963 | struct bfq_group_data { |
964 | /* must be the first member */ |
965 | struct blkcg_policy_data pd; |
966 | |
967 | unsigned int weight; |
968 | }; |
969 | |
970 | /** |
971 | * struct bfq_group - per (device, cgroup) data structure. |
972 | * @entity: schedulable entity to insert into the parent group sched_data. |
973 | * @sched_data: own sched_data, to contain child entities (they may be |
974 | * both bfq_queues and bfq_groups). |
975 | * @bfqd: the bfq_data for the device this group acts upon. |
976 | * @async_bfqq: array of async queues for all the tasks belonging to |
977 | * the group, one queue per ioprio value per ioprio_class, |
978 | * except for the idle class that has only one queue. |
979 | * @async_idle_bfqq: async queue for the idle class (ioprio is ignored). |
980 | * @my_entity: pointer to @entity, %NULL for the toplevel group; used |
981 | * to avoid too many special cases during group creation/ |
982 | * migration. |
983 | * @stats: stats for this bfqg. |
984 | * @active_entities: number of active entities belonging to the group; |
985 | * unused for the root group. Used to know whether there |
986 | * are groups with more than one active @bfq_entity |
987 | * (see the comments to the function |
988 | * bfq_bfqq_may_idle()). |
989 | * @rq_pos_tree: rbtree sorted by next_request position, used when |
990 | * determining if two or more queues have interleaving |
991 | * requests (see bfq_find_close_cooperator()). |
992 | * |
993 | * Each (device, cgroup) pair has its own bfq_group, i.e., for each cgroup |
994 | * there is a set of bfq_groups, each one collecting the lower-level |
995 | * entities belonging to the group that are acting on the same device. |
996 | * |
997 | * Locking works as follows: |
998 | * o @bfqd is protected by the queue lock, RCU is used to access it |
999 | * from the readers. |
1000 | * o All the other fields are protected by the @bfqd queue lock. |
1001 | */ |
1002 | struct bfq_group { |
1003 | /* must be the first member */ |
1004 | struct blkg_policy_data pd; |
1005 | |
1006 | /* cached path for this blkg (see comments in bfq_bic_update_cgroup) */ |
1007 | char blkg_path[128]; |
1008 | |
1009 | /* reference counter (see comments in bfq_bic_update_cgroup) */ |
1010 | refcount_t ref; |
1011 | |
1012 | struct bfq_entity entity; |
1013 | struct bfq_sched_data sched_data; |
1014 | |
1015 | struct bfq_data *bfqd; |
1016 | |
1017 | struct bfq_queue *async_bfqq[2][IOPRIO_NR_LEVELS][BFQ_MAX_ACTUATORS]; |
1018 | struct bfq_queue *async_idle_bfqq[BFQ_MAX_ACTUATORS]; |
1019 | |
1020 | struct bfq_entity *my_entity; |
1021 | |
1022 | int active_entities; |
1023 | int num_queues_with_pending_reqs; |
1024 | |
1025 | struct rb_root rq_pos_tree; |
1026 | |
1027 | struct bfqg_stats stats; |
1028 | }; |
1029 | |
1030 | #else |
1031 | struct bfq_group { |
1032 | struct bfq_entity entity; |
1033 | struct bfq_sched_data sched_data; |
1034 | |
1035 | struct bfq_queue *async_bfqq[2][IOPRIO_NR_LEVELS][BFQ_MAX_ACTUATORS]; |
1036 | struct bfq_queue *async_idle_bfqq[BFQ_MAX_ACTUATORS]; |
1037 | |
1038 | struct rb_root rq_pos_tree; |
1039 | }; |
1040 | #endif |
1041 | |
1042 | /* --------------- main algorithm interface ----------------- */ |
1043 | |
1044 | #define BFQ_SERVICE_TREE_INIT ((struct bfq_service_tree) \ |
1045 | { RB_ROOT, RB_ROOT, NULL, NULL, 0, 0 }) |
1046 | |
1047 | extern const int bfq_timeout; |
1048 | |
1049 | struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync, |
1050 | unsigned int actuator_idx); |
1051 | void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync, |
1052 | unsigned int actuator_idx); |
1053 | struct bfq_data *bic_to_bfqd(struct bfq_io_cq *bic); |
1054 | void bfq_pos_tree_add_move(struct bfq_data *bfqd, struct bfq_queue *bfqq); |
1055 | void bfq_weights_tree_add(struct bfq_queue *bfqq); |
1056 | void bfq_weights_tree_remove(struct bfq_queue *bfqq); |
1057 | void bfq_bfqq_expire(struct bfq_data *bfqd, struct bfq_queue *bfqq, |
1058 | bool compensate, enum bfqq_expiration reason); |
1059 | void bfq_put_queue(struct bfq_queue *bfqq); |
1060 | void bfq_put_cooperator(struct bfq_queue *bfqq); |
1061 | void bfq_end_wr_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg); |
1062 | void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq); |
1063 | void bfq_schedule_dispatch(struct bfq_data *bfqd); |
1064 | void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg); |
1065 | |
1066 | /* ------------ end of main algorithm interface -------------- */ |
1067 | |
1068 | /* ---------------- cgroups-support interface ---------------- */ |
1069 | |
1070 | void bfqg_stats_update_legacy_io(struct request_queue *q, struct request *rq); |
1071 | void bfqg_stats_update_io_remove(struct bfq_group *bfqg, blk_opf_t opf); |
1072 | void bfqg_stats_update_io_merged(struct bfq_group *bfqg, blk_opf_t opf); |
1073 | void bfqg_stats_update_completion(struct bfq_group *bfqg, u64 start_time_ns, |
1074 | u64 io_start_time_ns, blk_opf_t opf); |
1075 | void bfqg_stats_update_dequeue(struct bfq_group *bfqg); |
1076 | void bfqg_stats_set_start_idle_time(struct bfq_group *bfqg); |
1077 | void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq, |
1078 | struct bfq_group *bfqg); |
1079 | |
1080 | #ifdef CONFIG_BFQ_CGROUP_DEBUG |
1081 | void bfqg_stats_update_io_add(struct bfq_group *bfqg, struct bfq_queue *bfqq, |
1082 | blk_opf_t opf); |
1083 | void bfqg_stats_set_start_empty_time(struct bfq_group *bfqg); |
1084 | void bfqg_stats_update_idle_time(struct bfq_group *bfqg); |
1085 | void bfqg_stats_update_avg_queue_size(struct bfq_group *bfqg); |
1086 | #endif |
1087 | |
1088 | void bfq_init_entity(struct bfq_entity *entity, struct bfq_group *bfqg); |
1089 | void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio); |
1090 | void bfq_end_wr_async(struct bfq_data *bfqd); |
1091 | struct bfq_group *bfq_bio_bfqg(struct bfq_data *bfqd, struct bio *bio); |
1092 | struct blkcg_gq *bfqg_to_blkg(struct bfq_group *bfqg); |
1093 | struct bfq_group *bfqq_group(struct bfq_queue *bfqq); |
1094 | struct bfq_group *bfq_create_group_hierarchy(struct bfq_data *bfqd, int node); |
1095 | void bfqg_and_blkg_put(struct bfq_group *bfqg); |
1096 | |
1097 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
1098 | extern struct cftype bfq_blkcg_legacy_files[]; |
1099 | extern struct cftype bfq_blkg_files[]; |
1100 | extern struct blkcg_policy blkcg_policy_bfq; |
1101 | #endif |
1102 | |
1103 | /* ------------- end of cgroups-support interface ------------- */ |
1104 | |
1105 | /* - interface of the internal hierarchical B-WF2Q+ scheduler - */ |
1106 | |
1107 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
1108 | /* both next loops stop at one of the child entities of the root group */ |
1109 | #define for_each_entity(entity) \ |
1110 | for (; entity ; entity = entity->parent) |
1111 | |
1112 | /* |
1113 | * For each iteration, compute parent in advance, so as to be safe if |
1114 | * entity is deallocated during the iteration. Such a deallocation may |
1115 | * happen as a consequence of a bfq_put_queue that frees the bfq_queue |
1116 | * containing entity. |
1117 | */ |
1118 | #define for_each_entity_safe(entity, parent) \ |
1119 | for (; entity && ({ parent = entity->parent; 1; }); entity = parent) |
1120 | |
1121 | #else /* CONFIG_BFQ_GROUP_IOSCHED */ |
1122 | /* |
1123 | * Next two macros are fake loops when cgroups support is not |
1124 | * enabled. I fact, in such a case, there is only one level to go up |
1125 | * (to reach the root group). |
1126 | */ |
1127 | #define for_each_entity(entity) \ |
1128 | for (; entity ; entity = NULL) |
1129 | |
1130 | #define for_each_entity_safe(entity, parent) \ |
1131 | for (parent = NULL; entity ; entity = parent) |
1132 | #endif /* CONFIG_BFQ_GROUP_IOSCHED */ |
1133 | |
1134 | struct bfq_queue *bfq_entity_to_bfqq(struct bfq_entity *entity); |
1135 | unsigned int bfq_tot_busy_queues(struct bfq_data *bfqd); |
1136 | struct bfq_service_tree *bfq_entity_service_tree(struct bfq_entity *entity); |
1137 | struct bfq_entity *bfq_entity_of(struct rb_node *node); |
1138 | unsigned short bfq_ioprio_to_weight(int ioprio); |
1139 | void bfq_put_idle_entity(struct bfq_service_tree *st, |
1140 | struct bfq_entity *entity); |
1141 | struct bfq_service_tree * |
1142 | __bfq_entity_update_weight_prio(struct bfq_service_tree *old_st, |
1143 | struct bfq_entity *entity, |
1144 | bool update_class_too); |
1145 | void bfq_bfqq_served(struct bfq_queue *bfqq, int served); |
1146 | void bfq_bfqq_charge_time(struct bfq_data *bfqd, struct bfq_queue *bfqq, |
1147 | unsigned long time_ms); |
1148 | bool __bfq_deactivate_entity(struct bfq_entity *entity, |
1149 | bool ins_into_idle_tree); |
1150 | bool next_queue_may_preempt(struct bfq_data *bfqd); |
1151 | struct bfq_queue *bfq_get_next_queue(struct bfq_data *bfqd); |
1152 | bool __bfq_bfqd_reset_in_service(struct bfq_data *bfqd); |
1153 | void bfq_deactivate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, |
1154 | bool ins_into_idle_tree, bool expiration); |
1155 | void bfq_activate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq); |
1156 | void bfq_requeue_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, |
1157 | bool expiration); |
1158 | void bfq_del_bfqq_busy(struct bfq_queue *bfqq, bool expiration); |
1159 | void bfq_add_bfqq_busy(struct bfq_queue *bfqq); |
1160 | void bfq_add_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq); |
1161 | void bfq_del_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq); |
1162 | |
1163 | /* --------------- end of interface of B-WF2Q+ ---------------- */ |
1164 | |
1165 | /* Logging facilities. */ |
1166 | static inline void bfq_bfqq_name(struct bfq_queue *bfqq, char *str, int len) |
1167 | { |
1168 | char type = bfq_bfqq_sync(bfqq) ? 'S' : 'A'; |
1169 | |
1170 | if (bfqq->pid != -1) |
1171 | snprintf(buf: str, size: len, fmt: "bfq%d%c" , bfqq->pid, type); |
1172 | else |
1173 | snprintf(buf: str, size: len, fmt: "bfqSHARED-%c" , type); |
1174 | } |
1175 | |
1176 | #ifdef CONFIG_BFQ_GROUP_IOSCHED |
1177 | struct bfq_group *bfqq_group(struct bfq_queue *bfqq); |
1178 | |
1179 | #define bfq_log_bfqq(bfqd, bfqq, fmt, args...) do { \ |
1180 | char pid_str[MAX_BFQQ_NAME_LENGTH]; \ |
1181 | if (likely(!blk_trace_note_message_enabled((bfqd)->queue))) \ |
1182 | break; \ |
1183 | bfq_bfqq_name((bfqq), pid_str, MAX_BFQQ_NAME_LENGTH); \ |
1184 | blk_add_cgroup_trace_msg((bfqd)->queue, \ |
1185 | &bfqg_to_blkg(bfqq_group(bfqq))->blkcg->css, \ |
1186 | "%s " fmt, pid_str, ##args); \ |
1187 | } while (0) |
1188 | |
1189 | #define bfq_log_bfqg(bfqd, bfqg, fmt, args...) do { \ |
1190 | blk_add_cgroup_trace_msg((bfqd)->queue, \ |
1191 | &bfqg_to_blkg(bfqg)->blkcg->css, fmt, ##args); \ |
1192 | } while (0) |
1193 | |
1194 | #else /* CONFIG_BFQ_GROUP_IOSCHED */ |
1195 | |
1196 | #define bfq_log_bfqq(bfqd, bfqq, fmt, args...) do { \ |
1197 | char pid_str[MAX_BFQQ_NAME_LENGTH]; \ |
1198 | if (likely(!blk_trace_note_message_enabled((bfqd)->queue))) \ |
1199 | break; \ |
1200 | bfq_bfqq_name((bfqq), pid_str, MAX_BFQQ_NAME_LENGTH); \ |
1201 | blk_add_trace_msg((bfqd)->queue, "%s " fmt, pid_str, ##args); \ |
1202 | } while (0) |
1203 | #define bfq_log_bfqg(bfqd, bfqg, fmt, args...) do {} while (0) |
1204 | |
1205 | #endif /* CONFIG_BFQ_GROUP_IOSCHED */ |
1206 | |
1207 | #define bfq_log(bfqd, fmt, args...) \ |
1208 | blk_add_trace_msg((bfqd)->queue, "bfq " fmt, ##args) |
1209 | |
1210 | #endif /* _BFQ_H */ |
1211 | |