Commit | Line | Data |
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8c16567d | 1 | // SPDX-License-Identifier: GPL-2.0 |
00e04393 OS |
2 | /* |
3 | * The Kyber I/O scheduler. Controls latency by throttling queue depths using | |
4 | * scalable techniques. | |
5 | * | |
6 | * Copyright (C) 2017 Facebook | |
00e04393 OS |
7 | */ |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/blkdev.h> | |
00e04393 OS |
11 | #include <linux/module.h> |
12 | #include <linux/sbitmap.h> | |
13 | ||
b357e4a6 CK |
14 | #include <trace/events/block.h> |
15 | ||
2e9bc346 | 16 | #include "elevator.h" |
00e04393 OS |
17 | #include "blk.h" |
18 | #include "blk-mq.h" | |
16b738f6 | 19 | #include "blk-mq-debugfs.h" |
00e04393 | 20 | #include "blk-mq-sched.h" |
00e04393 | 21 | |
6c3b7af1 OS |
22 | #define CREATE_TRACE_POINTS |
23 | #include <trace/events/kyber.h> | |
24 | ||
6e25cb01 OS |
25 | /* |
26 | * Scheduling domains: the device is divided into multiple domains based on the | |
27 | * request type. | |
28 | */ | |
00e04393 OS |
29 | enum { |
30 | KYBER_READ, | |
6e25cb01 OS |
31 | KYBER_WRITE, |
32 | KYBER_DISCARD, | |
33 | KYBER_OTHER, | |
00e04393 OS |
34 | KYBER_NUM_DOMAINS, |
35 | }; | |
36 | ||
6c3b7af1 OS |
37 | static const char *kyber_domain_names[] = { |
38 | [KYBER_READ] = "READ", | |
39 | [KYBER_WRITE] = "WRITE", | |
40 | [KYBER_DISCARD] = "DISCARD", | |
41 | [KYBER_OTHER] = "OTHER", | |
42 | }; | |
43 | ||
00e04393 | 44 | enum { |
00e04393 OS |
45 | /* |
46 | * In order to prevent starvation of synchronous requests by a flood of | |
47 | * asynchronous requests, we reserve 25% of requests for synchronous | |
48 | * operations. | |
49 | */ | |
50 | KYBER_ASYNC_PERCENT = 75, | |
51 | }; | |
52 | ||
53 | /* | |
6e25cb01 | 54 | * Maximum device-wide depth for each scheduling domain. |
00e04393 | 55 | * |
6e25cb01 OS |
56 | * Even for fast devices with lots of tags like NVMe, you can saturate the |
57 | * device with only a fraction of the maximum possible queue depth. So, we cap | |
58 | * these to a reasonable value. | |
00e04393 OS |
59 | */ |
60 | static const unsigned int kyber_depth[] = { | |
61 | [KYBER_READ] = 256, | |
6e25cb01 OS |
62 | [KYBER_WRITE] = 128, |
63 | [KYBER_DISCARD] = 64, | |
64 | [KYBER_OTHER] = 16, | |
00e04393 OS |
65 | }; |
66 | ||
67 | /* | |
6e25cb01 OS |
68 | * Default latency targets for each scheduling domain. |
69 | */ | |
70 | static const u64 kyber_latency_targets[] = { | |
f0a0cddd OS |
71 | [KYBER_READ] = 2ULL * NSEC_PER_MSEC, |
72 | [KYBER_WRITE] = 10ULL * NSEC_PER_MSEC, | |
73 | [KYBER_DISCARD] = 5ULL * NSEC_PER_SEC, | |
6e25cb01 OS |
74 | }; |
75 | ||
76 | /* | |
77 | * Batch size (number of requests we'll dispatch in a row) for each scheduling | |
78 | * domain. | |
00e04393 OS |
79 | */ |
80 | static const unsigned int kyber_batch_size[] = { | |
81 | [KYBER_READ] = 16, | |
6e25cb01 OS |
82 | [KYBER_WRITE] = 8, |
83 | [KYBER_DISCARD] = 1, | |
84 | [KYBER_OTHER] = 1, | |
85 | }; | |
86 | ||
87 | /* | |
88 | * Requests latencies are recorded in a histogram with buckets defined relative | |
89 | * to the target latency: | |
90 | * | |
91 | * <= 1/4 * target latency | |
92 | * <= 1/2 * target latency | |
93 | * <= 3/4 * target latency | |
94 | * <= target latency | |
95 | * <= 1 1/4 * target latency | |
96 | * <= 1 1/2 * target latency | |
97 | * <= 1 3/4 * target latency | |
98 | * > 1 3/4 * target latency | |
99 | */ | |
100 | enum { | |
101 | /* | |
102 | * The width of the latency histogram buckets is | |
103 | * 1 / (1 << KYBER_LATENCY_SHIFT) * target latency. | |
104 | */ | |
105 | KYBER_LATENCY_SHIFT = 2, | |
106 | /* | |
107 | * The first (1 << KYBER_LATENCY_SHIFT) buckets are <= target latency, | |
108 | * thus, "good". | |
109 | */ | |
110 | KYBER_GOOD_BUCKETS = 1 << KYBER_LATENCY_SHIFT, | |
111 | /* There are also (1 << KYBER_LATENCY_SHIFT) "bad" buckets. */ | |
112 | KYBER_LATENCY_BUCKETS = 2 << KYBER_LATENCY_SHIFT, | |
113 | }; | |
114 | ||
115 | /* | |
116 | * We measure both the total latency and the I/O latency (i.e., latency after | |
117 | * submitting to the device). | |
118 | */ | |
119 | enum { | |
120 | KYBER_TOTAL_LATENCY, | |
121 | KYBER_IO_LATENCY, | |
122 | }; | |
123 | ||
6c3b7af1 OS |
124 | static const char *kyber_latency_type_names[] = { |
125 | [KYBER_TOTAL_LATENCY] = "total", | |
126 | [KYBER_IO_LATENCY] = "I/O", | |
127 | }; | |
128 | ||
6e25cb01 OS |
129 | /* |
130 | * Per-cpu latency histograms: total latency and I/O latency for each scheduling | |
131 | * domain except for KYBER_OTHER. | |
132 | */ | |
133 | struct kyber_cpu_latency { | |
134 | atomic_t buckets[KYBER_OTHER][2][KYBER_LATENCY_BUCKETS]; | |
00e04393 OS |
135 | }; |
136 | ||
a6088845 JW |
137 | /* |
138 | * There is a same mapping between ctx & hctx and kcq & khd, | |
139 | * we use request->mq_ctx->index_hw to index the kcq in khd. | |
140 | */ | |
141 | struct kyber_ctx_queue { | |
142 | /* | |
143 | * Used to ensure operations on rq_list and kcq_map to be an atmoic one. | |
144 | * Also protect the rqs on rq_list when merge. | |
145 | */ | |
146 | spinlock_t lock; | |
147 | struct list_head rq_list[KYBER_NUM_DOMAINS]; | |
148 | } ____cacheline_aligned_in_smp; | |
149 | ||
00e04393 | 150 | struct kyber_queue_data { |
6c3b7af1 | 151 | struct request_queue *q; |
c4110804 | 152 | dev_t dev; |
6c3b7af1 | 153 | |
00e04393 | 154 | /* |
6e25cb01 OS |
155 | * Each scheduling domain has a limited number of in-flight requests |
156 | * device-wide, limited by these tokens. | |
00e04393 OS |
157 | */ |
158 | struct sbitmap_queue domain_tokens[KYBER_NUM_DOMAINS]; | |
159 | ||
160 | /* | |
161 | * Async request percentage, converted to per-word depth for | |
162 | * sbitmap_get_shallow(). | |
163 | */ | |
164 | unsigned int async_depth; | |
165 | ||
6e25cb01 OS |
166 | struct kyber_cpu_latency __percpu *cpu_latency; |
167 | ||
168 | /* Timer for stats aggregation and adjusting domain tokens. */ | |
169 | struct timer_list timer; | |
170 | ||
171 | unsigned int latency_buckets[KYBER_OTHER][2][KYBER_LATENCY_BUCKETS]; | |
172 | ||
173 | unsigned long latency_timeout[KYBER_OTHER]; | |
174 | ||
175 | int domain_p99[KYBER_OTHER]; | |
176 | ||
00e04393 | 177 | /* Target latencies in nanoseconds. */ |
6e25cb01 | 178 | u64 latency_targets[KYBER_OTHER]; |
00e04393 OS |
179 | }; |
180 | ||
181 | struct kyber_hctx_data { | |
182 | spinlock_t lock; | |
183 | struct list_head rqs[KYBER_NUM_DOMAINS]; | |
184 | unsigned int cur_domain; | |
185 | unsigned int batching; | |
a6088845 JW |
186 | struct kyber_ctx_queue *kcqs; |
187 | struct sbitmap kcq_map[KYBER_NUM_DOMAINS]; | |
00203ba4 | 188 | struct sbq_wait domain_wait[KYBER_NUM_DOMAINS]; |
fcf38cdf | 189 | struct sbq_wait_state *domain_ws[KYBER_NUM_DOMAINS]; |
00e04393 OS |
190 | atomic_t wait_index[KYBER_NUM_DOMAINS]; |
191 | }; | |
192 | ||
fcf38cdf OS |
193 | static int kyber_domain_wake(wait_queue_entry_t *wait, unsigned mode, int flags, |
194 | void *key); | |
195 | ||
d625fecd | 196 | static unsigned int kyber_sched_domain(blk_opf_t opf) |
00e04393 | 197 | { |
d625fecd | 198 | switch (opf & REQ_OP_MASK) { |
6e25cb01 | 199 | case REQ_OP_READ: |
00e04393 | 200 | return KYBER_READ; |
6e25cb01 OS |
201 | case REQ_OP_WRITE: |
202 | return KYBER_WRITE; | |
203 | case REQ_OP_DISCARD: | |
204 | return KYBER_DISCARD; | |
205 | default: | |
00e04393 | 206 | return KYBER_OTHER; |
6e25cb01 | 207 | } |
00e04393 OS |
208 | } |
209 | ||
6e25cb01 OS |
210 | static void flush_latency_buckets(struct kyber_queue_data *kqd, |
211 | struct kyber_cpu_latency *cpu_latency, | |
212 | unsigned int sched_domain, unsigned int type) | |
00e04393 | 213 | { |
6e25cb01 OS |
214 | unsigned int *buckets = kqd->latency_buckets[sched_domain][type]; |
215 | atomic_t *cpu_buckets = cpu_latency->buckets[sched_domain][type]; | |
216 | unsigned int bucket; | |
00e04393 | 217 | |
6e25cb01 OS |
218 | for (bucket = 0; bucket < KYBER_LATENCY_BUCKETS; bucket++) |
219 | buckets[bucket] += atomic_xchg(&cpu_buckets[bucket], 0); | |
00e04393 OS |
220 | } |
221 | ||
222 | /* | |
6e25cb01 OS |
223 | * Calculate the histogram bucket with the given percentile rank, or -1 if there |
224 | * aren't enough samples yet. | |
00e04393 | 225 | */ |
6e25cb01 OS |
226 | static int calculate_percentile(struct kyber_queue_data *kqd, |
227 | unsigned int sched_domain, unsigned int type, | |
228 | unsigned int percentile) | |
00e04393 | 229 | { |
6e25cb01 OS |
230 | unsigned int *buckets = kqd->latency_buckets[sched_domain][type]; |
231 | unsigned int bucket, samples = 0, percentile_samples; | |
232 | ||
233 | for (bucket = 0; bucket < KYBER_LATENCY_BUCKETS; bucket++) | |
234 | samples += buckets[bucket]; | |
235 | ||
236 | if (!samples) | |
237 | return -1; | |
00e04393 OS |
238 | |
239 | /* | |
6e25cb01 OS |
240 | * We do the calculation once we have 500 samples or one second passes |
241 | * since the first sample was recorded, whichever comes first. | |
00e04393 | 242 | */ |
6e25cb01 OS |
243 | if (!kqd->latency_timeout[sched_domain]) |
244 | kqd->latency_timeout[sched_domain] = max(jiffies + HZ, 1UL); | |
245 | if (samples < 500 && | |
246 | time_is_after_jiffies(kqd->latency_timeout[sched_domain])) { | |
247 | return -1; | |
248 | } | |
249 | kqd->latency_timeout[sched_domain] = 0; | |
00e04393 | 250 | |
6e25cb01 OS |
251 | percentile_samples = DIV_ROUND_UP(samples * percentile, 100); |
252 | for (bucket = 0; bucket < KYBER_LATENCY_BUCKETS - 1; bucket++) { | |
253 | if (buckets[bucket] >= percentile_samples) | |
00e04393 | 254 | break; |
6e25cb01 | 255 | percentile_samples -= buckets[bucket]; |
00e04393 | 256 | } |
6e25cb01 | 257 | memset(buckets, 0, sizeof(kqd->latency_buckets[sched_domain][type])); |
00e04393 | 258 | |
c4110804 | 259 | trace_kyber_latency(kqd->dev, kyber_domain_names[sched_domain], |
6c3b7af1 OS |
260 | kyber_latency_type_names[type], percentile, |
261 | bucket + 1, 1 << KYBER_LATENCY_SHIFT, samples); | |
262 | ||
6e25cb01 OS |
263 | return bucket; |
264 | } | |
265 | ||
266 | static void kyber_resize_domain(struct kyber_queue_data *kqd, | |
267 | unsigned int sched_domain, unsigned int depth) | |
268 | { | |
00e04393 | 269 | depth = clamp(depth, 1U, kyber_depth[sched_domain]); |
6c3b7af1 | 270 | if (depth != kqd->domain_tokens[sched_domain].sb.depth) { |
00e04393 | 271 | sbitmap_queue_resize(&kqd->domain_tokens[sched_domain], depth); |
c4110804 | 272 | trace_kyber_adjust(kqd->dev, kyber_domain_names[sched_domain], |
6c3b7af1 OS |
273 | depth); |
274 | } | |
00e04393 OS |
275 | } |
276 | ||
6e25cb01 OS |
277 | static void kyber_timer_fn(struct timer_list *t) |
278 | { | |
279 | struct kyber_queue_data *kqd = from_timer(kqd, t, timer); | |
280 | unsigned int sched_domain; | |
281 | int cpu; | |
282 | bool bad = false; | |
283 | ||
284 | /* Sum all of the per-cpu latency histograms. */ | |
285 | for_each_online_cpu(cpu) { | |
286 | struct kyber_cpu_latency *cpu_latency; | |
287 | ||
288 | cpu_latency = per_cpu_ptr(kqd->cpu_latency, cpu); | |
289 | for (sched_domain = 0; sched_domain < KYBER_OTHER; sched_domain++) { | |
290 | flush_latency_buckets(kqd, cpu_latency, sched_domain, | |
291 | KYBER_TOTAL_LATENCY); | |
292 | flush_latency_buckets(kqd, cpu_latency, sched_domain, | |
293 | KYBER_IO_LATENCY); | |
00e04393 OS |
294 | } |
295 | } | |
296 | ||
6e25cb01 OS |
297 | /* |
298 | * Check if any domains have a high I/O latency, which might indicate | |
299 | * congestion in the device. Note that we use the p90; we don't want to | |
300 | * be too sensitive to outliers here. | |
301 | */ | |
302 | for (sched_domain = 0; sched_domain < KYBER_OTHER; sched_domain++) { | |
303 | int p90; | |
00e04393 | 304 | |
6e25cb01 OS |
305 | p90 = calculate_percentile(kqd, sched_domain, KYBER_IO_LATENCY, |
306 | 90); | |
307 | if (p90 >= KYBER_GOOD_BUCKETS) | |
308 | bad = true; | |
309 | } | |
00e04393 OS |
310 | |
311 | /* | |
6e25cb01 OS |
312 | * Adjust the scheduling domain depths. If we determined that there was |
313 | * congestion, we throttle all domains with good latencies. Either way, | |
314 | * we ease up on throttling domains with bad latencies. | |
00e04393 | 315 | */ |
6e25cb01 OS |
316 | for (sched_domain = 0; sched_domain < KYBER_OTHER; sched_domain++) { |
317 | unsigned int orig_depth, depth; | |
318 | int p99; | |
319 | ||
320 | p99 = calculate_percentile(kqd, sched_domain, | |
321 | KYBER_TOTAL_LATENCY, 99); | |
322 | /* | |
323 | * This is kind of subtle: different domains will not | |
324 | * necessarily have enough samples to calculate the latency | |
325 | * percentiles during the same window, so we have to remember | |
326 | * the p99 for the next time we observe congestion; once we do, | |
327 | * we don't want to throttle again until we get more data, so we | |
328 | * reset it to -1. | |
329 | */ | |
330 | if (bad) { | |
331 | if (p99 < 0) | |
332 | p99 = kqd->domain_p99[sched_domain]; | |
333 | kqd->domain_p99[sched_domain] = -1; | |
334 | } else if (p99 >= 0) { | |
335 | kqd->domain_p99[sched_domain] = p99; | |
336 | } | |
337 | if (p99 < 0) | |
338 | continue; | |
339 | ||
340 | /* | |
341 | * If this domain has bad latency, throttle less. Otherwise, | |
342 | * throttle more iff we determined that there is congestion. | |
343 | * | |
344 | * The new depth is scaled linearly with the p99 latency vs the | |
345 | * latency target. E.g., if the p99 is 3/4 of the target, then | |
346 | * we throttle down to 3/4 of the current depth, and if the p99 | |
347 | * is 2x the target, then we double the depth. | |
348 | */ | |
349 | if (bad || p99 >= KYBER_GOOD_BUCKETS) { | |
350 | orig_depth = kqd->domain_tokens[sched_domain].sb.depth; | |
351 | depth = (orig_depth * (p99 + 1)) >> KYBER_LATENCY_SHIFT; | |
352 | kyber_resize_domain(kqd, sched_domain, depth); | |
353 | } | |
354 | } | |
00e04393 OS |
355 | } |
356 | ||
00e04393 OS |
357 | static struct kyber_queue_data *kyber_queue_data_alloc(struct request_queue *q) |
358 | { | |
359 | struct kyber_queue_data *kqd; | |
00e04393 OS |
360 | int ret = -ENOMEM; |
361 | int i; | |
362 | ||
6e25cb01 | 363 | kqd = kzalloc_node(sizeof(*kqd), GFP_KERNEL, q->node); |
00e04393 OS |
364 | if (!kqd) |
365 | goto err; | |
00e04393 | 366 | |
6c3b7af1 | 367 | kqd->q = q; |
c4110804 | 368 | kqd->dev = disk_devt(q->disk); |
6c3b7af1 | 369 | |
6e25cb01 OS |
370 | kqd->cpu_latency = alloc_percpu_gfp(struct kyber_cpu_latency, |
371 | GFP_KERNEL | __GFP_ZERO); | |
372 | if (!kqd->cpu_latency) | |
00e04393 OS |
373 | goto err_kqd; |
374 | ||
6e25cb01 OS |
375 | timer_setup(&kqd->timer, kyber_timer_fn, 0); |
376 | ||
00e04393 OS |
377 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) { |
378 | WARN_ON(!kyber_depth[i]); | |
379 | WARN_ON(!kyber_batch_size[i]); | |
380 | ret = sbitmap_queue_init_node(&kqd->domain_tokens[i], | |
fa2a1f60 OS |
381 | kyber_depth[i], -1, false, |
382 | GFP_KERNEL, q->node); | |
00e04393 OS |
383 | if (ret) { |
384 | while (--i >= 0) | |
385 | sbitmap_queue_free(&kqd->domain_tokens[i]); | |
6e25cb01 | 386 | goto err_buckets; |
00e04393 | 387 | } |
00e04393 OS |
388 | } |
389 | ||
6e25cb01 OS |
390 | for (i = 0; i < KYBER_OTHER; i++) { |
391 | kqd->domain_p99[i] = -1; | |
392 | kqd->latency_targets[i] = kyber_latency_targets[i]; | |
393 | } | |
00e04393 | 394 | |
00e04393 OS |
395 | return kqd; |
396 | ||
6e25cb01 OS |
397 | err_buckets: |
398 | free_percpu(kqd->cpu_latency); | |
00e04393 OS |
399 | err_kqd: |
400 | kfree(kqd); | |
401 | err: | |
402 | return ERR_PTR(ret); | |
403 | } | |
404 | ||
405 | static int kyber_init_sched(struct request_queue *q, struct elevator_type *e) | |
406 | { | |
407 | struct kyber_queue_data *kqd; | |
408 | struct elevator_queue *eq; | |
409 | ||
410 | eq = elevator_alloc(q, e); | |
411 | if (!eq) | |
412 | return -ENOMEM; | |
413 | ||
414 | kqd = kyber_queue_data_alloc(q); | |
415 | if (IS_ERR(kqd)) { | |
416 | kobject_put(&eq->kobj); | |
417 | return PTR_ERR(kqd); | |
418 | } | |
419 | ||
6e25cb01 OS |
420 | blk_stat_enable_accounting(q); |
421 | ||
4d337ceb ML |
422 | blk_queue_flag_clear(QUEUE_FLAG_SQ_SCHED, q); |
423 | ||
00e04393 OS |
424 | eq->elevator_data = kqd; |
425 | q->elevator = eq; | |
426 | ||
00e04393 OS |
427 | return 0; |
428 | } | |
429 | ||
430 | static void kyber_exit_sched(struct elevator_queue *e) | |
431 | { | |
432 | struct kyber_queue_data *kqd = e->elevator_data; | |
00e04393 OS |
433 | int i; |
434 | ||
292a089d | 435 | timer_shutdown_sync(&kqd->timer); |
68497092 | 436 | blk_stat_disable_accounting(kqd->q); |
00e04393 OS |
437 | |
438 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) | |
439 | sbitmap_queue_free(&kqd->domain_tokens[i]); | |
6e25cb01 | 440 | free_percpu(kqd->cpu_latency); |
00e04393 OS |
441 | kfree(kqd); |
442 | } | |
443 | ||
a6088845 JW |
444 | static void kyber_ctx_queue_init(struct kyber_ctx_queue *kcq) |
445 | { | |
446 | unsigned int i; | |
447 | ||
448 | spin_lock_init(&kcq->lock); | |
449 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) | |
450 | INIT_LIST_HEAD(&kcq->rq_list[i]); | |
451 | } | |
452 | ||
ffa772cf | 453 | static void kyber_depth_updated(struct blk_mq_hw_ctx *hctx) |
00e04393 | 454 | { |
28820640 | 455 | struct kyber_queue_data *kqd = hctx->queue->elevator->elevator_data; |
ffa772cf | 456 | struct blk_mq_tags *tags = hctx->sched_tags; |
ae0f1a73 | 457 | unsigned int shift = tags->bitmap_tags.sb.shift; |
ffa772cf YY |
458 | |
459 | kqd->async_depth = (1U << shift) * KYBER_ASYNC_PERCENT / 100U; | |
460 | ||
ae0f1a73 | 461 | sbitmap_queue_min_shallow_depth(&tags->bitmap_tags, kqd->async_depth); |
ffa772cf YY |
462 | } |
463 | ||
464 | static int kyber_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
465 | { | |
00e04393 OS |
466 | struct kyber_hctx_data *khd; |
467 | int i; | |
468 | ||
469 | khd = kmalloc_node(sizeof(*khd), GFP_KERNEL, hctx->numa_node); | |
470 | if (!khd) | |
471 | return -ENOMEM; | |
472 | ||
a6088845 JW |
473 | khd->kcqs = kmalloc_array_node(hctx->nr_ctx, |
474 | sizeof(struct kyber_ctx_queue), | |
475 | GFP_KERNEL, hctx->numa_node); | |
476 | if (!khd->kcqs) | |
477 | goto err_khd; | |
478 | ||
479 | for (i = 0; i < hctx->nr_ctx; i++) | |
480 | kyber_ctx_queue_init(&khd->kcqs[i]); | |
481 | ||
482 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) { | |
483 | if (sbitmap_init_node(&khd->kcq_map[i], hctx->nr_ctx, | |
efe1f3a1 | 484 | ilog2(8), GFP_KERNEL, hctx->numa_node, |
c548e62b | 485 | false, false)) { |
a6088845 JW |
486 | while (--i >= 0) |
487 | sbitmap_free(&khd->kcq_map[i]); | |
488 | goto err_kcqs; | |
489 | } | |
490 | } | |
491 | ||
00e04393 OS |
492 | spin_lock_init(&khd->lock); |
493 | ||
494 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) { | |
495 | INIT_LIST_HEAD(&khd->rqs[i]); | |
00203ba4 JA |
496 | khd->domain_wait[i].sbq = NULL; |
497 | init_waitqueue_func_entry(&khd->domain_wait[i].wait, | |
fcf38cdf | 498 | kyber_domain_wake); |
00203ba4 JA |
499 | khd->domain_wait[i].wait.private = hctx; |
500 | INIT_LIST_HEAD(&khd->domain_wait[i].wait.entry); | |
00e04393 OS |
501 | atomic_set(&khd->wait_index[i], 0); |
502 | } | |
503 | ||
504 | khd->cur_domain = 0; | |
505 | khd->batching = 0; | |
506 | ||
507 | hctx->sched_data = khd; | |
ffa772cf | 508 | kyber_depth_updated(hctx); |
00e04393 OS |
509 | |
510 | return 0; | |
a6088845 JW |
511 | |
512 | err_kcqs: | |
513 | kfree(khd->kcqs); | |
514 | err_khd: | |
515 | kfree(khd); | |
516 | return -ENOMEM; | |
00e04393 OS |
517 | } |
518 | ||
519 | static void kyber_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) | |
520 | { | |
a6088845 JW |
521 | struct kyber_hctx_data *khd = hctx->sched_data; |
522 | int i; | |
523 | ||
524 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) | |
525 | sbitmap_free(&khd->kcq_map[i]); | |
526 | kfree(khd->kcqs); | |
00e04393 OS |
527 | kfree(hctx->sched_data); |
528 | } | |
529 | ||
530 | static int rq_get_domain_token(struct request *rq) | |
531 | { | |
532 | return (long)rq->elv.priv[0]; | |
533 | } | |
534 | ||
535 | static void rq_set_domain_token(struct request *rq, int token) | |
536 | { | |
537 | rq->elv.priv[0] = (void *)(long)token; | |
538 | } | |
539 | ||
540 | static void rq_clear_domain_token(struct kyber_queue_data *kqd, | |
541 | struct request *rq) | |
542 | { | |
543 | unsigned int sched_domain; | |
544 | int nr; | |
545 | ||
546 | nr = rq_get_domain_token(rq); | |
547 | if (nr != -1) { | |
a6088845 | 548 | sched_domain = kyber_sched_domain(rq->cmd_flags); |
00e04393 OS |
549 | sbitmap_queue_clear(&kqd->domain_tokens[sched_domain], nr, |
550 | rq->mq_ctx->cpu); | |
551 | } | |
552 | } | |
553 | ||
d625fecd | 554 | static void kyber_limit_depth(blk_opf_t opf, struct blk_mq_alloc_data *data) |
00e04393 | 555 | { |
00e04393 OS |
556 | /* |
557 | * We use the scheduler tags as per-hardware queue queueing tokens. | |
558 | * Async requests can be limited at this stage. | |
559 | */ | |
d625fecd | 560 | if (!op_is_sync(opf)) { |
5bbf4e5a CH |
561 | struct kyber_queue_data *kqd = data->q->elevator->elevator_data; |
562 | ||
00e04393 | 563 | data->shallow_depth = kqd->async_depth; |
5bbf4e5a CH |
564 | } |
565 | } | |
00e04393 | 566 | |
efed9a33 | 567 | static bool kyber_bio_merge(struct request_queue *q, struct bio *bio, |
14ccb66b | 568 | unsigned int nr_segs) |
a6088845 | 569 | { |
efed9a33 OS |
570 | struct blk_mq_ctx *ctx = blk_mq_get_ctx(q); |
571 | struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, bio->bi_opf, ctx); | |
a6088845 | 572 | struct kyber_hctx_data *khd = hctx->sched_data; |
f31967f0 | 573 | struct kyber_ctx_queue *kcq = &khd->kcqs[ctx->index_hw[hctx->type]]; |
a6088845 JW |
574 | unsigned int sched_domain = kyber_sched_domain(bio->bi_opf); |
575 | struct list_head *rq_list = &kcq->rq_list[sched_domain]; | |
576 | bool merged; | |
577 | ||
578 | spin_lock(&kcq->lock); | |
bdc6a287 | 579 | merged = blk_bio_list_merge(hctx->queue, rq_list, bio, nr_segs); |
a6088845 | 580 | spin_unlock(&kcq->lock); |
a6088845 JW |
581 | |
582 | return merged; | |
583 | } | |
584 | ||
5d9c305b | 585 | static void kyber_prepare_request(struct request *rq) |
5bbf4e5a CH |
586 | { |
587 | rq_set_domain_token(rq, -1); | |
00e04393 OS |
588 | } |
589 | ||
a6088845 | 590 | static void kyber_insert_requests(struct blk_mq_hw_ctx *hctx, |
93fffe16 CH |
591 | struct list_head *rq_list, |
592 | blk_insert_t flags) | |
a6088845 JW |
593 | { |
594 | struct kyber_hctx_data *khd = hctx->sched_data; | |
595 | struct request *rq, *next; | |
596 | ||
597 | list_for_each_entry_safe(rq, next, rq_list, queuelist) { | |
598 | unsigned int sched_domain = kyber_sched_domain(rq->cmd_flags); | |
f31967f0 | 599 | struct kyber_ctx_queue *kcq = &khd->kcqs[rq->mq_ctx->index_hw[hctx->type]]; |
a6088845 JW |
600 | struct list_head *head = &kcq->rq_list[sched_domain]; |
601 | ||
602 | spin_lock(&kcq->lock); | |
fb7b9b02 | 603 | trace_block_rq_insert(rq); |
93fffe16 | 604 | if (flags & BLK_MQ_INSERT_AT_HEAD) |
a6088845 JW |
605 | list_move(&rq->queuelist, head); |
606 | else | |
607 | list_move_tail(&rq->queuelist, head); | |
608 | sbitmap_set_bit(&khd->kcq_map[sched_domain], | |
f31967f0 | 609 | rq->mq_ctx->index_hw[hctx->type]); |
a6088845 JW |
610 | spin_unlock(&kcq->lock); |
611 | } | |
612 | } | |
613 | ||
7b9e9361 | 614 | static void kyber_finish_request(struct request *rq) |
00e04393 | 615 | { |
7b9e9361 | 616 | struct kyber_queue_data *kqd = rq->q->elevator->elevator_data; |
00e04393 OS |
617 | |
618 | rq_clear_domain_token(kqd, rq); | |
00e04393 OS |
619 | } |
620 | ||
6e25cb01 OS |
621 | static void add_latency_sample(struct kyber_cpu_latency *cpu_latency, |
622 | unsigned int sched_domain, unsigned int type, | |
623 | u64 target, u64 latency) | |
00e04393 | 624 | { |
6e25cb01 OS |
625 | unsigned int bucket; |
626 | u64 divisor; | |
00e04393 | 627 | |
6e25cb01 OS |
628 | if (latency > 0) { |
629 | divisor = max_t(u64, target >> KYBER_LATENCY_SHIFT, 1); | |
630 | bucket = min_t(unsigned int, div64_u64(latency - 1, divisor), | |
631 | KYBER_LATENCY_BUCKETS - 1); | |
632 | } else { | |
633 | bucket = 0; | |
00e04393 OS |
634 | } |
635 | ||
6e25cb01 OS |
636 | atomic_inc(&cpu_latency->buckets[sched_domain][type][bucket]); |
637 | } | |
00e04393 | 638 | |
6e25cb01 OS |
639 | static void kyber_completed_request(struct request *rq, u64 now) |
640 | { | |
641 | struct kyber_queue_data *kqd = rq->q->elevator->elevator_data; | |
642 | struct kyber_cpu_latency *cpu_latency; | |
643 | unsigned int sched_domain; | |
644 | u64 target; | |
645 | ||
646 | sched_domain = kyber_sched_domain(rq->cmd_flags); | |
647 | if (sched_domain == KYBER_OTHER) | |
00e04393 OS |
648 | return; |
649 | ||
6e25cb01 OS |
650 | cpu_latency = get_cpu_ptr(kqd->cpu_latency); |
651 | target = kqd->latency_targets[sched_domain]; | |
652 | add_latency_sample(cpu_latency, sched_domain, KYBER_TOTAL_LATENCY, | |
653 | target, now - rq->start_time_ns); | |
654 | add_latency_sample(cpu_latency, sched_domain, KYBER_IO_LATENCY, target, | |
655 | now - rq->io_start_time_ns); | |
656 | put_cpu_ptr(kqd->cpu_latency); | |
00e04393 | 657 | |
6e25cb01 | 658 | timer_reduce(&kqd->timer, jiffies + HZ / 10); |
00e04393 OS |
659 | } |
660 | ||
a6088845 JW |
661 | struct flush_kcq_data { |
662 | struct kyber_hctx_data *khd; | |
663 | unsigned int sched_domain; | |
664 | struct list_head *list; | |
665 | }; | |
666 | ||
667 | static bool flush_busy_kcq(struct sbitmap *sb, unsigned int bitnr, void *data) | |
00e04393 | 668 | { |
a6088845 JW |
669 | struct flush_kcq_data *flush_data = data; |
670 | struct kyber_ctx_queue *kcq = &flush_data->khd->kcqs[bitnr]; | |
00e04393 | 671 | |
a6088845 JW |
672 | spin_lock(&kcq->lock); |
673 | list_splice_tail_init(&kcq->rq_list[flush_data->sched_domain], | |
674 | flush_data->list); | |
675 | sbitmap_clear_bit(sb, bitnr); | |
676 | spin_unlock(&kcq->lock); | |
00e04393 | 677 | |
a6088845 JW |
678 | return true; |
679 | } | |
680 | ||
681 | static void kyber_flush_busy_kcqs(struct kyber_hctx_data *khd, | |
682 | unsigned int sched_domain, | |
683 | struct list_head *list) | |
684 | { | |
685 | struct flush_kcq_data data = { | |
686 | .khd = khd, | |
687 | .sched_domain = sched_domain, | |
688 | .list = list, | |
689 | }; | |
690 | ||
691 | sbitmap_for_each_set(&khd->kcq_map[sched_domain], | |
692 | flush_busy_kcq, &data); | |
00e04393 OS |
693 | } |
694 | ||
00203ba4 | 695 | static int kyber_domain_wake(wait_queue_entry_t *wqe, unsigned mode, int flags, |
00e04393 OS |
696 | void *key) |
697 | { | |
00203ba4 JA |
698 | struct blk_mq_hw_ctx *hctx = READ_ONCE(wqe->private); |
699 | struct sbq_wait *wait = container_of(wqe, struct sbq_wait, wait); | |
00e04393 | 700 | |
00203ba4 | 701 | sbitmap_del_wait_queue(wait); |
00e04393 OS |
702 | blk_mq_run_hw_queue(hctx, true); |
703 | return 1; | |
704 | } | |
705 | ||
706 | static int kyber_get_domain_token(struct kyber_queue_data *kqd, | |
707 | struct kyber_hctx_data *khd, | |
708 | struct blk_mq_hw_ctx *hctx) | |
709 | { | |
710 | unsigned int sched_domain = khd->cur_domain; | |
711 | struct sbitmap_queue *domain_tokens = &kqd->domain_tokens[sched_domain]; | |
00203ba4 | 712 | struct sbq_wait *wait = &khd->domain_wait[sched_domain]; |
00e04393 OS |
713 | struct sbq_wait_state *ws; |
714 | int nr; | |
715 | ||
716 | nr = __sbitmap_queue_get(domain_tokens); | |
00e04393 OS |
717 | |
718 | /* | |
719 | * If we failed to get a domain token, make sure the hardware queue is | |
720 | * run when one becomes available. Note that this is serialized on | |
721 | * khd->lock, but we still need to be careful about the waker. | |
722 | */ | |
00203ba4 | 723 | if (nr < 0 && list_empty_careful(&wait->wait.entry)) { |
00e04393 OS |
724 | ws = sbq_wait_ptr(domain_tokens, |
725 | &khd->wait_index[sched_domain]); | |
fcf38cdf | 726 | khd->domain_ws[sched_domain] = ws; |
00203ba4 | 727 | sbitmap_add_wait_queue(domain_tokens, ws, wait); |
00e04393 OS |
728 | |
729 | /* | |
730 | * Try again in case a token was freed before we got on the wait | |
fcf38cdf | 731 | * queue. |
00e04393 OS |
732 | */ |
733 | nr = __sbitmap_queue_get(domain_tokens); | |
fcf38cdf | 734 | } |
8cf46660 | 735 | |
fcf38cdf OS |
736 | /* |
737 | * If we got a token while we were on the wait queue, remove ourselves | |
738 | * from the wait queue to ensure that all wake ups make forward | |
739 | * progress. It's possible that the waker already deleted the entry | |
740 | * between the !list_empty_careful() check and us grabbing the lock, but | |
741 | * list_del_init() is okay with that. | |
742 | */ | |
00203ba4 | 743 | if (nr >= 0 && !list_empty_careful(&wait->wait.entry)) { |
fcf38cdf OS |
744 | ws = khd->domain_ws[sched_domain]; |
745 | spin_lock_irq(&ws->wait.lock); | |
00203ba4 | 746 | sbitmap_del_wait_queue(wait); |
fcf38cdf | 747 | spin_unlock_irq(&ws->wait.lock); |
00e04393 | 748 | } |
fcf38cdf | 749 | |
00e04393 OS |
750 | return nr; |
751 | } | |
752 | ||
753 | static struct request * | |
754 | kyber_dispatch_cur_domain(struct kyber_queue_data *kqd, | |
755 | struct kyber_hctx_data *khd, | |
a6088845 | 756 | struct blk_mq_hw_ctx *hctx) |
00e04393 OS |
757 | { |
758 | struct list_head *rqs; | |
759 | struct request *rq; | |
760 | int nr; | |
761 | ||
762 | rqs = &khd->rqs[khd->cur_domain]; | |
00e04393 OS |
763 | |
764 | /* | |
a6088845 JW |
765 | * If we already have a flushed request, then we just need to get a |
766 | * token for it. Otherwise, if there are pending requests in the kcqs, | |
767 | * flush the kcqs, but only if we can get a token. If not, we should | |
768 | * leave the requests in the kcqs so that they can be merged. Note that | |
769 | * khd->lock serializes the flushes, so if we observed any bit set in | |
770 | * the kcq_map, we will always get a request. | |
00e04393 | 771 | */ |
a6088845 | 772 | rq = list_first_entry_or_null(rqs, struct request, queuelist); |
00e04393 OS |
773 | if (rq) { |
774 | nr = kyber_get_domain_token(kqd, khd, hctx); | |
775 | if (nr >= 0) { | |
776 | khd->batching++; | |
777 | rq_set_domain_token(rq, nr); | |
778 | list_del_init(&rq->queuelist); | |
779 | return rq; | |
6c3b7af1 | 780 | } else { |
c4110804 | 781 | trace_kyber_throttled(kqd->dev, |
6c3b7af1 | 782 | kyber_domain_names[khd->cur_domain]); |
00e04393 | 783 | } |
a6088845 JW |
784 | } else if (sbitmap_any_bit_set(&khd->kcq_map[khd->cur_domain])) { |
785 | nr = kyber_get_domain_token(kqd, khd, hctx); | |
786 | if (nr >= 0) { | |
787 | kyber_flush_busy_kcqs(khd, khd->cur_domain, rqs); | |
788 | rq = list_first_entry(rqs, struct request, queuelist); | |
789 | khd->batching++; | |
790 | rq_set_domain_token(rq, nr); | |
791 | list_del_init(&rq->queuelist); | |
792 | return rq; | |
6c3b7af1 | 793 | } else { |
c4110804 | 794 | trace_kyber_throttled(kqd->dev, |
6c3b7af1 | 795 | kyber_domain_names[khd->cur_domain]); |
a6088845 | 796 | } |
00e04393 OS |
797 | } |
798 | ||
799 | /* There were either no pending requests or no tokens. */ | |
800 | return NULL; | |
801 | } | |
802 | ||
803 | static struct request *kyber_dispatch_request(struct blk_mq_hw_ctx *hctx) | |
804 | { | |
805 | struct kyber_queue_data *kqd = hctx->queue->elevator->elevator_data; | |
806 | struct kyber_hctx_data *khd = hctx->sched_data; | |
00e04393 OS |
807 | struct request *rq; |
808 | int i; | |
809 | ||
810 | spin_lock(&khd->lock); | |
811 | ||
812 | /* | |
813 | * First, if we are still entitled to batch, try to dispatch a request | |
814 | * from the batch. | |
815 | */ | |
816 | if (khd->batching < kyber_batch_size[khd->cur_domain]) { | |
a6088845 | 817 | rq = kyber_dispatch_cur_domain(kqd, khd, hctx); |
00e04393 OS |
818 | if (rq) |
819 | goto out; | |
820 | } | |
821 | ||
822 | /* | |
823 | * Either, | |
824 | * 1. We were no longer entitled to a batch. | |
825 | * 2. The domain we were batching didn't have any requests. | |
826 | * 3. The domain we were batching was out of tokens. | |
827 | * | |
828 | * Start another batch. Note that this wraps back around to the original | |
829 | * domain if no other domains have requests or tokens. | |
830 | */ | |
831 | khd->batching = 0; | |
832 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) { | |
833 | if (khd->cur_domain == KYBER_NUM_DOMAINS - 1) | |
834 | khd->cur_domain = 0; | |
835 | else | |
836 | khd->cur_domain++; | |
837 | ||
a6088845 | 838 | rq = kyber_dispatch_cur_domain(kqd, khd, hctx); |
00e04393 OS |
839 | if (rq) |
840 | goto out; | |
841 | } | |
842 | ||
843 | rq = NULL; | |
844 | out: | |
845 | spin_unlock(&khd->lock); | |
846 | return rq; | |
847 | } | |
848 | ||
849 | static bool kyber_has_work(struct blk_mq_hw_ctx *hctx) | |
850 | { | |
851 | struct kyber_hctx_data *khd = hctx->sched_data; | |
852 | int i; | |
853 | ||
854 | for (i = 0; i < KYBER_NUM_DOMAINS; i++) { | |
a6088845 JW |
855 | if (!list_empty_careful(&khd->rqs[i]) || |
856 | sbitmap_any_bit_set(&khd->kcq_map[i])) | |
00e04393 OS |
857 | return true; |
858 | } | |
a6088845 JW |
859 | |
860 | return false; | |
00e04393 OS |
861 | } |
862 | ||
6e25cb01 OS |
863 | #define KYBER_LAT_SHOW_STORE(domain, name) \ |
864 | static ssize_t kyber_##name##_lat_show(struct elevator_queue *e, \ | |
865 | char *page) \ | |
00e04393 OS |
866 | { \ |
867 | struct kyber_queue_data *kqd = e->elevator_data; \ | |
868 | \ | |
6e25cb01 | 869 | return sprintf(page, "%llu\n", kqd->latency_targets[domain]); \ |
00e04393 OS |
870 | } \ |
871 | \ | |
6e25cb01 OS |
872 | static ssize_t kyber_##name##_lat_store(struct elevator_queue *e, \ |
873 | const char *page, size_t count) \ | |
00e04393 OS |
874 | { \ |
875 | struct kyber_queue_data *kqd = e->elevator_data; \ | |
876 | unsigned long long nsec; \ | |
877 | int ret; \ | |
878 | \ | |
879 | ret = kstrtoull(page, 10, &nsec); \ | |
880 | if (ret) \ | |
881 | return ret; \ | |
882 | \ | |
6e25cb01 | 883 | kqd->latency_targets[domain] = nsec; \ |
00e04393 OS |
884 | \ |
885 | return count; \ | |
886 | } | |
6e25cb01 OS |
887 | KYBER_LAT_SHOW_STORE(KYBER_READ, read); |
888 | KYBER_LAT_SHOW_STORE(KYBER_WRITE, write); | |
00e04393 OS |
889 | #undef KYBER_LAT_SHOW_STORE |
890 | ||
891 | #define KYBER_LAT_ATTR(op) __ATTR(op##_lat_nsec, 0644, kyber_##op##_lat_show, kyber_##op##_lat_store) | |
892 | static struct elv_fs_entry kyber_sched_attrs[] = { | |
893 | KYBER_LAT_ATTR(read), | |
894 | KYBER_LAT_ATTR(write), | |
895 | __ATTR_NULL | |
896 | }; | |
897 | #undef KYBER_LAT_ATTR | |
898 | ||
16b738f6 OS |
899 | #ifdef CONFIG_BLK_DEBUG_FS |
900 | #define KYBER_DEBUGFS_DOMAIN_ATTRS(domain, name) \ | |
901 | static int kyber_##name##_tokens_show(void *data, struct seq_file *m) \ | |
902 | { \ | |
903 | struct request_queue *q = data; \ | |
904 | struct kyber_queue_data *kqd = q->elevator->elevator_data; \ | |
905 | \ | |
906 | sbitmap_queue_show(&kqd->domain_tokens[domain], m); \ | |
907 | return 0; \ | |
908 | } \ | |
909 | \ | |
910 | static void *kyber_##name##_rqs_start(struct seq_file *m, loff_t *pos) \ | |
911 | __acquires(&khd->lock) \ | |
912 | { \ | |
913 | struct blk_mq_hw_ctx *hctx = m->private; \ | |
914 | struct kyber_hctx_data *khd = hctx->sched_data; \ | |
915 | \ | |
916 | spin_lock(&khd->lock); \ | |
917 | return seq_list_start(&khd->rqs[domain], *pos); \ | |
918 | } \ | |
919 | \ | |
920 | static void *kyber_##name##_rqs_next(struct seq_file *m, void *v, \ | |
921 | loff_t *pos) \ | |
922 | { \ | |
923 | struct blk_mq_hw_ctx *hctx = m->private; \ | |
924 | struct kyber_hctx_data *khd = hctx->sched_data; \ | |
925 | \ | |
926 | return seq_list_next(v, &khd->rqs[domain], pos); \ | |
927 | } \ | |
928 | \ | |
929 | static void kyber_##name##_rqs_stop(struct seq_file *m, void *v) \ | |
930 | __releases(&khd->lock) \ | |
931 | { \ | |
932 | struct blk_mq_hw_ctx *hctx = m->private; \ | |
933 | struct kyber_hctx_data *khd = hctx->sched_data; \ | |
934 | \ | |
935 | spin_unlock(&khd->lock); \ | |
936 | } \ | |
937 | \ | |
938 | static const struct seq_operations kyber_##name##_rqs_seq_ops = { \ | |
939 | .start = kyber_##name##_rqs_start, \ | |
940 | .next = kyber_##name##_rqs_next, \ | |
941 | .stop = kyber_##name##_rqs_stop, \ | |
942 | .show = blk_mq_debugfs_rq_show, \ | |
943 | }; \ | |
944 | \ | |
945 | static int kyber_##name##_waiting_show(void *data, struct seq_file *m) \ | |
946 | { \ | |
947 | struct blk_mq_hw_ctx *hctx = data; \ | |
948 | struct kyber_hctx_data *khd = hctx->sched_data; \ | |
00203ba4 | 949 | wait_queue_entry_t *wait = &khd->domain_wait[domain].wait; \ |
16b738f6 | 950 | \ |
2055da97 | 951 | seq_printf(m, "%d\n", !list_empty_careful(&wait->entry)); \ |
16b738f6 OS |
952 | return 0; \ |
953 | } | |
954 | KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_READ, read) | |
6e25cb01 OS |
955 | KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_WRITE, write) |
956 | KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_DISCARD, discard) | |
16b738f6 OS |
957 | KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_OTHER, other) |
958 | #undef KYBER_DEBUGFS_DOMAIN_ATTRS | |
959 | ||
960 | static int kyber_async_depth_show(void *data, struct seq_file *m) | |
961 | { | |
962 | struct request_queue *q = data; | |
963 | struct kyber_queue_data *kqd = q->elevator->elevator_data; | |
964 | ||
965 | seq_printf(m, "%u\n", kqd->async_depth); | |
966 | return 0; | |
967 | } | |
968 | ||
969 | static int kyber_cur_domain_show(void *data, struct seq_file *m) | |
970 | { | |
971 | struct blk_mq_hw_ctx *hctx = data; | |
972 | struct kyber_hctx_data *khd = hctx->sched_data; | |
973 | ||
6c3b7af1 | 974 | seq_printf(m, "%s\n", kyber_domain_names[khd->cur_domain]); |
16b738f6 OS |
975 | return 0; |
976 | } | |
977 | ||
978 | static int kyber_batching_show(void *data, struct seq_file *m) | |
979 | { | |
980 | struct blk_mq_hw_ctx *hctx = data; | |
981 | struct kyber_hctx_data *khd = hctx->sched_data; | |
982 | ||
983 | seq_printf(m, "%u\n", khd->batching); | |
984 | return 0; | |
985 | } | |
986 | ||
987 | #define KYBER_QUEUE_DOMAIN_ATTRS(name) \ | |
988 | {#name "_tokens", 0400, kyber_##name##_tokens_show} | |
989 | static const struct blk_mq_debugfs_attr kyber_queue_debugfs_attrs[] = { | |
990 | KYBER_QUEUE_DOMAIN_ATTRS(read), | |
6e25cb01 OS |
991 | KYBER_QUEUE_DOMAIN_ATTRS(write), |
992 | KYBER_QUEUE_DOMAIN_ATTRS(discard), | |
16b738f6 OS |
993 | KYBER_QUEUE_DOMAIN_ATTRS(other), |
994 | {"async_depth", 0400, kyber_async_depth_show}, | |
995 | {}, | |
996 | }; | |
997 | #undef KYBER_QUEUE_DOMAIN_ATTRS | |
998 | ||
999 | #define KYBER_HCTX_DOMAIN_ATTRS(name) \ | |
1000 | {#name "_rqs", 0400, .seq_ops = &kyber_##name##_rqs_seq_ops}, \ | |
1001 | {#name "_waiting", 0400, kyber_##name##_waiting_show} | |
1002 | static const struct blk_mq_debugfs_attr kyber_hctx_debugfs_attrs[] = { | |
1003 | KYBER_HCTX_DOMAIN_ATTRS(read), | |
6e25cb01 OS |
1004 | KYBER_HCTX_DOMAIN_ATTRS(write), |
1005 | KYBER_HCTX_DOMAIN_ATTRS(discard), | |
16b738f6 OS |
1006 | KYBER_HCTX_DOMAIN_ATTRS(other), |
1007 | {"cur_domain", 0400, kyber_cur_domain_show}, | |
1008 | {"batching", 0400, kyber_batching_show}, | |
1009 | {}, | |
1010 | }; | |
1011 | #undef KYBER_HCTX_DOMAIN_ATTRS | |
1012 | #endif | |
1013 | ||
00e04393 | 1014 | static struct elevator_type kyber_sched = { |
f9cd4bfe | 1015 | .ops = { |
00e04393 OS |
1016 | .init_sched = kyber_init_sched, |
1017 | .exit_sched = kyber_exit_sched, | |
1018 | .init_hctx = kyber_init_hctx, | |
1019 | .exit_hctx = kyber_exit_hctx, | |
5bbf4e5a | 1020 | .limit_depth = kyber_limit_depth, |
a6088845 | 1021 | .bio_merge = kyber_bio_merge, |
5bbf4e5a | 1022 | .prepare_request = kyber_prepare_request, |
a6088845 | 1023 | .insert_requests = kyber_insert_requests, |
7b9e9361 | 1024 | .finish_request = kyber_finish_request, |
ba989a01 | 1025 | .requeue_request = kyber_finish_request, |
00e04393 OS |
1026 | .completed_request = kyber_completed_request, |
1027 | .dispatch_request = kyber_dispatch_request, | |
1028 | .has_work = kyber_has_work, | |
ffa772cf | 1029 | .depth_updated = kyber_depth_updated, |
00e04393 | 1030 | }, |
16b738f6 OS |
1031 | #ifdef CONFIG_BLK_DEBUG_FS |
1032 | .queue_debugfs_attrs = kyber_queue_debugfs_attrs, | |
1033 | .hctx_debugfs_attrs = kyber_hctx_debugfs_attrs, | |
1034 | #endif | |
00e04393 OS |
1035 | .elevator_attrs = kyber_sched_attrs, |
1036 | .elevator_name = "kyber", | |
1037 | .elevator_owner = THIS_MODULE, | |
1038 | }; | |
1039 | ||
1040 | static int __init kyber_init(void) | |
1041 | { | |
1042 | return elv_register(&kyber_sched); | |
1043 | } | |
1044 | ||
1045 | static void __exit kyber_exit(void) | |
1046 | { | |
1047 | elv_unregister(&kyber_sched); | |
1048 | } | |
1049 | ||
1050 | module_init(kyber_init); | |
1051 | module_exit(kyber_exit); | |
1052 | ||
1053 | MODULE_AUTHOR("Omar Sandoval"); | |
1054 | MODULE_LICENSE("GPL"); | |
1055 | MODULE_DESCRIPTION("Kyber I/O scheduler"); |