Blame view
block/blk-throttle.c
67.5 KB
b24413180 License cleanup: ... |
1 |
// SPDX-License-Identifier: GPL-2.0 |
e43473b7f blkio: Core imple... |
2 3 4 5 6 7 8 9 10 11 12 |
/* * Interface for controlling IO bandwidth on a request queue * * Copyright (C) 2010 Vivek Goyal <vgoyal@redhat.com> */ #include <linux/module.h> #include <linux/slab.h> #include <linux/blkdev.h> #include <linux/bio.h> #include <linux/blktrace_api.h> |
eea8f41cc blkcg: move block... |
13 |
#include <linux/blk-cgroup.h> |
bc9fcbf9c block: move blk_t... |
14 |
#include "blk.h" |
1d156646e blk-cgroup: separ... |
15 |
#include "blk-cgroup-rwstat.h" |
e43473b7f blkio: Core imple... |
16 17 |
/* Max dispatch from a group in 1 round */ |
e675df2ad blk-throttle: Def... |
18 |
#define THROTL_GRP_QUANTUM 8 |
e43473b7f blkio: Core imple... |
19 20 |
/* Total max dispatch from all groups in one round */ |
e675df2ad blk-throttle: Def... |
21 |
#define THROTL_QUANTUM 32 |
e43473b7f blkio: Core imple... |
22 |
|
d61fcfa4b blk-throttle: cho... |
23 24 25 |
/* Throttling is performed over a slice and after that slice is renewed */ #define DFL_THROTL_SLICE_HD (HZ / 10) #define DFL_THROTL_SLICE_SSD (HZ / 50) |
297e3d854 blk-throttle: mak... |
26 |
#define MAX_THROTL_SLICE (HZ) |
9e234eeaf blk-throttle: add... |
27 |
#define MAX_IDLE_TIME (5L * 1000 * 1000) /* 5 s */ |
9bb67aeb9 blk-throttle: res... |
28 29 |
#define MIN_THROTL_BPS (320 * 1024) #define MIN_THROTL_IOPS (10) |
b4f428ef2 blk-throttle: for... |
30 31 |
#define DFL_LATENCY_TARGET (-1L) #define DFL_IDLE_THRESHOLD (0) |
6679a90c4 blk-throttle: set... |
32 33 34 35 36 37 38 |
#define DFL_HD_BASELINE_LATENCY (4000L) /* 4ms */ #define LATENCY_FILTERED_SSD (0) /* * For HD, very small latency comes from sequential IO. Such IO is helpless to * help determine if its IO is impacted by others, hence we ignore the IO */ #define LATENCY_FILTERED_HD (1000L) /* 1ms */ |
e43473b7f blkio: Core imple... |
39 |
|
3c798398e blkcg: mass renam... |
40 |
static struct blkcg_policy blkcg_policy_throtl; |
0381411e4 blkcg: let blkcg ... |
41 |
|
450adcbe5 blk-throttle: Do ... |
42 43 |
/* A workqueue to queue throttle related work */ static struct workqueue_struct *kthrotld_workqueue; |
450adcbe5 blk-throttle: Do ... |
44 |
|
c5cc2070b blk-throttle: add... |
45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 |
/* * To implement hierarchical throttling, throtl_grps form a tree and bios * are dispatched upwards level by level until they reach the top and get * issued. When dispatching bios from the children and local group at each * level, if the bios are dispatched into a single bio_list, there's a risk * of a local or child group which can queue many bios at once filling up * the list starving others. * * To avoid such starvation, dispatched bios are queued separately * according to where they came from. When they are again dispatched to * the parent, they're popped in round-robin order so that no single source * hogs the dispatch window. * * throtl_qnode is used to keep the queued bios separated by their sources. * Bios are queued to throtl_qnode which in turn is queued to * throtl_service_queue and then dispatched in round-robin order. * * It's also used to track the reference counts on blkg's. A qnode always * belongs to a throtl_grp and gets queued on itself or the parent, so * incrementing the reference of the associated throtl_grp when a qnode is * queued and decrementing when dequeued is enough to keep the whole blkg * tree pinned while bios are in flight. */ struct throtl_qnode { struct list_head node; /* service_queue->queued[] */ struct bio_list bios; /* queued bios */ struct throtl_grp *tg; /* tg this qnode belongs to */ }; |
c9e0332e8 blk-throttle: ren... |
73 |
struct throtl_service_queue { |
77216b048 blk-throttle: add... |
74 |
struct throtl_service_queue *parent_sq; /* the parent service_queue */ |
73f0d49a9 blk-throttle: mov... |
75 76 77 78 |
/* * Bios queued directly to this service_queue or dispatched from * children throtl_grp's. */ |
c5cc2070b blk-throttle: add... |
79 |
struct list_head queued[2]; /* throtl_qnode [READ/WRITE] */ |
73f0d49a9 blk-throttle: mov... |
80 81 82 83 84 85 |
unsigned int nr_queued[2]; /* number of queued bios */ /* * RB tree of active children throtl_grp's, which are sorted by * their ->disptime. */ |
9ff01255a Blk-throttle: upd... |
86 |
struct rb_root_cached pending_tree; /* RB tree of active tgs */ |
c9e0332e8 blk-throttle: ren... |
87 88 |
unsigned int nr_pending; /* # queued in the tree */ unsigned long first_pending_disptime; /* disptime of the first tg */ |
69df0ab03 blk-throttle: sep... |
89 |
struct timer_list pending_timer; /* fires on first_pending_disptime */ |
e43473b7f blkio: Core imple... |
90 |
}; |
5b2c16aae blk-throttle: sim... |
91 92 |
enum tg_state_flags { THROTL_TG_PENDING = 1 << 0, /* on parent's pending tree */ |
0e9f4164b blk-throttle: gen... |
93 |
THROTL_TG_WAS_EMPTY = 1 << 1, /* bio_lists[] became non-empty */ |
5b2c16aae blk-throttle: sim... |
94 |
}; |
e43473b7f blkio: Core imple... |
95 |
#define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node) |
9f626e372 blk-throttle: pre... |
96 |
enum { |
cd5ab1b0f blk-throttle: add... |
97 |
LIMIT_LOW, |
9f626e372 blk-throttle: pre... |
98 99 100 |
LIMIT_MAX, LIMIT_CNT, }; |
e43473b7f blkio: Core imple... |
101 |
struct throtl_grp { |
f95a04afa blkcg: embed stru... |
102 103 |
/* must be the first member */ struct blkg_policy_data pd; |
c9e0332e8 blk-throttle: ren... |
104 |
/* active throtl group service_queue member */ |
e43473b7f blkio: Core imple... |
105 |
struct rb_node rb_node; |
0f3457f60 blk-throttle: add... |
106 107 |
/* throtl_data this group belongs to */ struct throtl_data *td; |
49a2f1e3f blk-throttle: add... |
108 109 |
/* this group's service queue */ struct throtl_service_queue service_queue; |
e43473b7f blkio: Core imple... |
110 |
/* |
c5cc2070b blk-throttle: add... |
111 112 113 114 115 116 117 118 119 120 121 |
* qnode_on_self is used when bios are directly queued to this * throtl_grp so that local bios compete fairly with bios * dispatched from children. qnode_on_parent is used when bios are * dispatched from this throtl_grp into its parent and will compete * with the sibling qnode_on_parents and the parent's * qnode_on_self. */ struct throtl_qnode qnode_on_self[2]; struct throtl_qnode qnode_on_parent[2]; /* |
e43473b7f blkio: Core imple... |
122 123 124 125 126 |
* Dispatch time in jiffies. This is the estimated time when group * will unthrottle and is ready to dispatch more bio. It is used as * key to sort active groups in service tree. */ unsigned long disptime; |
e43473b7f blkio: Core imple... |
127 |
unsigned int flags; |
693e751e7 blk-throttle: imp... |
128 129 |
/* are there any throtl rules between this group and td? */ bool has_rules[2]; |
cd5ab1b0f blk-throttle: add... |
130 |
/* internally used bytes per second rate limits */ |
9f626e372 blk-throttle: pre... |
131 |
uint64_t bps[2][LIMIT_CNT]; |
cd5ab1b0f blk-throttle: add... |
132 133 |
/* user configured bps limits */ uint64_t bps_conf[2][LIMIT_CNT]; |
e43473b7f blkio: Core imple... |
134 |
|
cd5ab1b0f blk-throttle: add... |
135 |
/* internally used IOPS limits */ |
9f626e372 blk-throttle: pre... |
136 |
unsigned int iops[2][LIMIT_CNT]; |
cd5ab1b0f blk-throttle: add... |
137 138 |
/* user configured IOPS limits */ unsigned int iops_conf[2][LIMIT_CNT]; |
8e89d13f4 blkio: Implementa... |
139 |
|
b53b072c4 blk-throttle: Fix... |
140 |
/* Number of bytes dispatched in current slice */ |
e43473b7f blkio: Core imple... |
141 |
uint64_t bytes_disp[2]; |
8e89d13f4 blkio: Implementa... |
142 143 |
/* Number of bio's dispatched in current slice */ unsigned int io_disp[2]; |
e43473b7f blkio: Core imple... |
144 |
|
3f0abd806 blk-throttle: add... |
145 146 147 148 149 150 |
unsigned long last_low_overflow_time[2]; uint64_t last_bytes_disp[2]; unsigned int last_io_disp[2]; unsigned long last_check_time; |
ec80991d6 blk-throttle: add... |
151 |
unsigned long latency_target; /* us */ |
5b81fc3cc blk-throttle: add... |
152 |
unsigned long latency_target_conf; /* us */ |
e43473b7f blkio: Core imple... |
153 154 155 |
/* When did we start a new slice */ unsigned long slice_start[2]; unsigned long slice_end[2]; |
9e234eeaf blk-throttle: add... |
156 157 158 159 160 |
unsigned long last_finish_time; /* ns / 1024 */ unsigned long checked_last_finish_time; /* ns / 1024 */ unsigned long avg_idletime; /* ns / 1024 */ unsigned long idletime_threshold; /* us */ |
5b81fc3cc blk-throttle: add... |
161 |
unsigned long idletime_threshold_conf; /* us */ |
53696b8d2 blk-throttle: add... |
162 163 164 165 |
unsigned int bio_cnt; /* total bios */ unsigned int bad_bio_cnt; /* bios exceeding latency threshold */ unsigned long bio_cnt_reset_time; |
7ca464383 blk-throtl: stop ... |
166 167 168 |
struct blkg_rwstat stat_bytes; struct blkg_rwstat stat_ios; |
e43473b7f blkio: Core imple... |
169 |
}; |
b9147dd1b blk-throttle: add... |
170 171 172 173 174 175 176 177 178 179 180 181 |
/* We measure latency for request size from <= 4k to >= 1M */ #define LATENCY_BUCKET_SIZE 9 struct latency_bucket { unsigned long total_latency; /* ns / 1024 */ int samples; }; struct avg_latency_bucket { unsigned long latency; /* ns / 1024 */ bool valid; }; |
e43473b7f blkio: Core imple... |
182 183 |
struct throtl_data { |
e43473b7f blkio: Core imple... |
184 |
/* service tree for active throtl groups */ |
c9e0332e8 blk-throttle: ren... |
185 |
struct throtl_service_queue service_queue; |
e43473b7f blkio: Core imple... |
186 |
|
e43473b7f blkio: Core imple... |
187 188 189 190 |
struct request_queue *queue; /* Total Number of queued bios on READ and WRITE lists */ unsigned int nr_queued[2]; |
297e3d854 blk-throttle: mak... |
191 |
unsigned int throtl_slice; |
e43473b7f blkio: Core imple... |
192 |
/* Work for dispatching throttled bios */ |
69df0ab03 blk-throttle: sep... |
193 |
struct work_struct dispatch_work; |
9f626e372 blk-throttle: pre... |
194 195 |
unsigned int limit_index; bool limit_valid[LIMIT_CNT]; |
3f0abd806 blk-throttle: add... |
196 197 198 |
unsigned long low_upgrade_time; unsigned long low_downgrade_time; |
7394e31fa blk-throttle: mak... |
199 200 |
unsigned int scale; |
b9147dd1b blk-throttle: add... |
201 |
|
b889bf66d blk-throttle: tra... |
202 203 204 |
struct latency_bucket tmp_buckets[2][LATENCY_BUCKET_SIZE]; struct avg_latency_bucket avg_buckets[2][LATENCY_BUCKET_SIZE]; struct latency_bucket __percpu *latency_buckets[2]; |
b9147dd1b blk-throttle: add... |
205 |
unsigned long last_calculate_time; |
6679a90c4 blk-throttle: set... |
206 |
unsigned long filtered_latency; |
b9147dd1b blk-throttle: add... |
207 208 |
bool track_bio_latency; |
e43473b7f blkio: Core imple... |
209 |
}; |
e99e88a9d treewide: setup_t... |
210 |
static void throtl_pending_timer_fn(struct timer_list *t); |
69df0ab03 blk-throttle: sep... |
211 |
|
f95a04afa blkcg: embed stru... |
212 213 214 215 |
static inline struct throtl_grp *pd_to_tg(struct blkg_policy_data *pd) { return pd ? container_of(pd, struct throtl_grp, pd) : NULL; } |
3c798398e blkcg: mass renam... |
216 |
static inline struct throtl_grp *blkg_to_tg(struct blkcg_gq *blkg) |
0381411e4 blkcg: let blkcg ... |
217 |
{ |
f95a04afa blkcg: embed stru... |
218 |
return pd_to_tg(blkg_to_pd(blkg, &blkcg_policy_throtl)); |
0381411e4 blkcg: let blkcg ... |
219 |
} |
3c798398e blkcg: mass renam... |
220 |
static inline struct blkcg_gq *tg_to_blkg(struct throtl_grp *tg) |
0381411e4 blkcg: let blkcg ... |
221 |
{ |
f95a04afa blkcg: embed stru... |
222 |
return pd_to_blkg(&tg->pd); |
0381411e4 blkcg: let blkcg ... |
223 |
} |
fda6f272c blk-throttle: imp... |
224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 |
/** * sq_to_tg - return the throl_grp the specified service queue belongs to * @sq: the throtl_service_queue of interest * * Return the throtl_grp @sq belongs to. If @sq is the top-level one * embedded in throtl_data, %NULL is returned. */ static struct throtl_grp *sq_to_tg(struct throtl_service_queue *sq) { if (sq && sq->parent_sq) return container_of(sq, struct throtl_grp, service_queue); else return NULL; } /** * sq_to_td - return throtl_data the specified service queue belongs to * @sq: the throtl_service_queue of interest * |
b43daedc0 scripts/spelling.... |
243 |
* A service_queue can be embedded in either a throtl_grp or throtl_data. |
fda6f272c blk-throttle: imp... |
244 245 246 247 248 249 250 251 252 253 254 |
* Determine the associated throtl_data accordingly and return it. */ static struct throtl_data *sq_to_td(struct throtl_service_queue *sq) { struct throtl_grp *tg = sq_to_tg(sq); if (tg) return tg->td; else return container_of(sq, struct throtl_data, service_queue); } |
7394e31fa blk-throttle: mak... |
255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 |
/* * cgroup's limit in LIMIT_MAX is scaled if low limit is set. This scale is to * make the IO dispatch more smooth. * Scale up: linearly scale up according to lapsed time since upgrade. For * every throtl_slice, the limit scales up 1/2 .low limit till the * limit hits .max limit * Scale down: exponentially scale down if a cgroup doesn't hit its .low limit */ static uint64_t throtl_adjusted_limit(uint64_t low, struct throtl_data *td) { /* arbitrary value to avoid too big scale */ if (td->scale < 4096 && time_after_eq(jiffies, td->low_upgrade_time + td->scale * td->throtl_slice)) td->scale = (jiffies - td->low_upgrade_time) / td->throtl_slice; return low + (low >> 1) * td->scale; } |
9f626e372 blk-throttle: pre... |
272 273 |
static uint64_t tg_bps_limit(struct throtl_grp *tg, int rw) { |
b22c417c8 blk-throttle: con... |
274 |
struct blkcg_gq *blkg = tg_to_blkg(tg); |
7394e31fa blk-throttle: mak... |
275 |
struct throtl_data *td; |
b22c417c8 blk-throttle: con... |
276 277 278 279 |
uint64_t ret; if (cgroup_subsys_on_dfl(io_cgrp_subsys) && !blkg->parent) return U64_MAX; |
7394e31fa blk-throttle: mak... |
280 281 282 |
td = tg->td; ret = tg->bps[rw][td->limit_index]; |
9bb67aeb9 blk-throttle: res... |
283 284 285 286 287 288 289 290 |
if (ret == 0 && td->limit_index == LIMIT_LOW) { /* intermediate node or iops isn't 0 */ if (!list_empty(&blkg->blkcg->css.children) || tg->iops[rw][td->limit_index]) return U64_MAX; else return MIN_THROTL_BPS; } |
7394e31fa blk-throttle: mak... |
291 292 293 294 295 296 297 298 |
if (td->limit_index == LIMIT_MAX && tg->bps[rw][LIMIT_LOW] && tg->bps[rw][LIMIT_LOW] != tg->bps[rw][LIMIT_MAX]) { uint64_t adjusted; adjusted = throtl_adjusted_limit(tg->bps[rw][LIMIT_LOW], td); ret = min(tg->bps[rw][LIMIT_MAX], adjusted); } |
b22c417c8 blk-throttle: con... |
299 |
return ret; |
9f626e372 blk-throttle: pre... |
300 301 302 303 |
} static unsigned int tg_iops_limit(struct throtl_grp *tg, int rw) { |
b22c417c8 blk-throttle: con... |
304 |
struct blkcg_gq *blkg = tg_to_blkg(tg); |
7394e31fa blk-throttle: mak... |
305 |
struct throtl_data *td; |
b22c417c8 blk-throttle: con... |
306 307 308 309 |
unsigned int ret; if (cgroup_subsys_on_dfl(io_cgrp_subsys) && !blkg->parent) return UINT_MAX; |
9bb67aeb9 blk-throttle: res... |
310 |
|
7394e31fa blk-throttle: mak... |
311 312 |
td = tg->td; ret = tg->iops[rw][td->limit_index]; |
9bb67aeb9 blk-throttle: res... |
313 314 315 316 317 318 319 320 |
if (ret == 0 && tg->td->limit_index == LIMIT_LOW) { /* intermediate node or bps isn't 0 */ if (!list_empty(&blkg->blkcg->css.children) || tg->bps[rw][td->limit_index]) return UINT_MAX; else return MIN_THROTL_IOPS; } |
7394e31fa blk-throttle: mak... |
321 322 323 324 325 326 327 328 329 330 |
if (td->limit_index == LIMIT_MAX && tg->iops[rw][LIMIT_LOW] && tg->iops[rw][LIMIT_LOW] != tg->iops[rw][LIMIT_MAX]) { uint64_t adjusted; adjusted = throtl_adjusted_limit(tg->iops[rw][LIMIT_LOW], td); if (adjusted > UINT_MAX) adjusted = UINT_MAX; ret = min_t(unsigned int, tg->iops[rw][LIMIT_MAX], adjusted); } |
b22c417c8 blk-throttle: con... |
331 |
return ret; |
9f626e372 blk-throttle: pre... |
332 |
} |
b9147dd1b blk-throttle: add... |
333 334 |
#define request_bucket_index(sectors) \ clamp_t(int, order_base_2(sectors) - 3, 0, LATENCY_BUCKET_SIZE - 1) |
fda6f272c blk-throttle: imp... |
335 336 337 338 339 340 341 342 |
/** * throtl_log - log debug message via blktrace * @sq: the service_queue being reported * @fmt: printf format string * @args: printf args * * The messages are prefixed with "throtl BLKG_NAME" if @sq belongs to a * throtl_grp; otherwise, just "throtl". |
fda6f272c blk-throttle: imp... |
343 344 345 346 347 348 |
*/ #define throtl_log(sq, fmt, args...) do { \ struct throtl_grp *__tg = sq_to_tg((sq)); \ struct throtl_data *__td = sq_to_td((sq)); \ \ (void)__td; \ |
59fa0224c blk-throttle: don... |
349 350 |
if (likely(!blk_trace_note_message_enabled(__td->queue))) \ break; \ |
fda6f272c blk-throttle: imp... |
351 |
if ((__tg)) { \ |
35fe6d763 block: use standa... |
352 353 |
blk_add_cgroup_trace_msg(__td->queue, \ tg_to_blkg(__tg)->blkcg, "throtl " fmt, ##args);\ |
fda6f272c blk-throttle: imp... |
354 355 356 |
} else { \ blk_add_trace_msg(__td->queue, "throtl " fmt, ##args); \ } \ |
54e7ed12b blkcg: remove blk... |
357 |
} while (0) |
e43473b7f blkio: Core imple... |
358 |
|
ea0ea2bc6 blk-throttle: cap... |
359 360 361 362 363 364 365 |
static inline unsigned int throtl_bio_data_size(struct bio *bio) { /* assume it's one sector */ if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) return 512; return bio->bi_iter.bi_size; } |
c5cc2070b blk-throttle: add... |
366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 |
static void throtl_qnode_init(struct throtl_qnode *qn, struct throtl_grp *tg) { INIT_LIST_HEAD(&qn->node); bio_list_init(&qn->bios); qn->tg = tg; } /** * throtl_qnode_add_bio - add a bio to a throtl_qnode and activate it * @bio: bio being added * @qn: qnode to add bio to * @queued: the service_queue->queued[] list @qn belongs to * * Add @bio to @qn and put @qn on @queued if it's not already on. * @qn->tg's reference count is bumped when @qn is activated. See the * comment on top of throtl_qnode definition for details. */ static void throtl_qnode_add_bio(struct bio *bio, struct throtl_qnode *qn, struct list_head *queued) { bio_list_add(&qn->bios, bio); if (list_empty(&qn->node)) { list_add_tail(&qn->node, queued); blkg_get(tg_to_blkg(qn->tg)); } } /** * throtl_peek_queued - peek the first bio on a qnode list * @queued: the qnode list to peek */ static struct bio *throtl_peek_queued(struct list_head *queued) { |
b7b609de5 blk-throttle: Mov... |
399 |
struct throtl_qnode *qn; |
c5cc2070b blk-throttle: add... |
400 401 402 403 |
struct bio *bio; if (list_empty(queued)) return NULL; |
b7b609de5 blk-throttle: Mov... |
404 |
qn = list_first_entry(queued, struct throtl_qnode, node); |
c5cc2070b blk-throttle: add... |
405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 |
bio = bio_list_peek(&qn->bios); WARN_ON_ONCE(!bio); return bio; } /** * throtl_pop_queued - pop the first bio form a qnode list * @queued: the qnode list to pop a bio from * @tg_to_put: optional out argument for throtl_grp to put * * Pop the first bio from the qnode list @queued. After popping, the first * qnode is removed from @queued if empty or moved to the end of @queued so * that the popping order is round-robin. * * When the first qnode is removed, its associated throtl_grp should be put * too. If @tg_to_put is NULL, this function automatically puts it; * otherwise, *@tg_to_put is set to the throtl_grp to put and the caller is * responsible for putting it. */ static struct bio *throtl_pop_queued(struct list_head *queued, struct throtl_grp **tg_to_put) { |
b7b609de5 blk-throttle: Mov... |
427 |
struct throtl_qnode *qn; |
c5cc2070b blk-throttle: add... |
428 429 430 431 |
struct bio *bio; if (list_empty(queued)) return NULL; |
b7b609de5 blk-throttle: Mov... |
432 |
qn = list_first_entry(queued, struct throtl_qnode, node); |
c5cc2070b blk-throttle: add... |
433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 |
bio = bio_list_pop(&qn->bios); WARN_ON_ONCE(!bio); if (bio_list_empty(&qn->bios)) { list_del_init(&qn->node); if (tg_to_put) *tg_to_put = qn->tg; else blkg_put(tg_to_blkg(qn->tg)); } else { list_move_tail(&qn->node, queued); } return bio; } |
49a2f1e3f blk-throttle: add... |
448 |
/* init a service_queue, assumes the caller zeroed it */ |
b2ce2643c blk-throttle: cle... |
449 |
static void throtl_service_queue_init(struct throtl_service_queue *sq) |
49a2f1e3f blk-throttle: add... |
450 |
{ |
c5cc2070b blk-throttle: add... |
451 452 |
INIT_LIST_HEAD(&sq->queued[0]); INIT_LIST_HEAD(&sq->queued[1]); |
9ff01255a Blk-throttle: upd... |
453 |
sq->pending_tree = RB_ROOT_CACHED; |
e99e88a9d treewide: setup_t... |
454 |
timer_setup(&sq->pending_timer, throtl_pending_timer_fn, 0); |
69df0ab03 blk-throttle: sep... |
455 |
} |
cf09a8ee1 blkcg: pass @q an... |
456 457 458 |
static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp, struct request_queue *q, struct blkcg *blkcg) |
001bea73e blkcg: replace bl... |
459 |
{ |
4fb72036f blk-throttle: rem... |
460 |
struct throtl_grp *tg; |
24bdb8ef0 blkcg: make blkcg... |
461 |
int rw; |
4fb72036f blk-throttle: rem... |
462 |
|
cf09a8ee1 blkcg: pass @q an... |
463 |
tg = kzalloc_node(sizeof(*tg), gfp, q->node); |
4fb72036f blk-throttle: rem... |
464 |
if (!tg) |
77ea73388 blkcg: move io_se... |
465 |
return NULL; |
4fb72036f blk-throttle: rem... |
466 |
|
7ca464383 blk-throtl: stop ... |
467 468 469 470 471 |
if (blkg_rwstat_init(&tg->stat_bytes, gfp)) goto err_free_tg; if (blkg_rwstat_init(&tg->stat_ios, gfp)) goto err_exit_stat_bytes; |
b2ce2643c blk-throttle: cle... |
472 473 474 475 476 477 478 479 |
throtl_service_queue_init(&tg->service_queue); for (rw = READ; rw <= WRITE; rw++) { throtl_qnode_init(&tg->qnode_on_self[rw], tg); throtl_qnode_init(&tg->qnode_on_parent[rw], tg); } RB_CLEAR_NODE(&tg->rb_node); |
9f626e372 blk-throttle: pre... |
480 481 482 483 |
tg->bps[READ][LIMIT_MAX] = U64_MAX; tg->bps[WRITE][LIMIT_MAX] = U64_MAX; tg->iops[READ][LIMIT_MAX] = UINT_MAX; tg->iops[WRITE][LIMIT_MAX] = UINT_MAX; |
cd5ab1b0f blk-throttle: add... |
484 485 486 487 488 |
tg->bps_conf[READ][LIMIT_MAX] = U64_MAX; tg->bps_conf[WRITE][LIMIT_MAX] = U64_MAX; tg->iops_conf[READ][LIMIT_MAX] = UINT_MAX; tg->iops_conf[WRITE][LIMIT_MAX] = UINT_MAX; /* LIMIT_LOW will have default value 0 */ |
b2ce2643c blk-throttle: cle... |
489 |
|
ec80991d6 blk-throttle: add... |
490 |
tg->latency_target = DFL_LATENCY_TARGET; |
5b81fc3cc blk-throttle: add... |
491 |
tg->latency_target_conf = DFL_LATENCY_TARGET; |
b4f428ef2 blk-throttle: for... |
492 493 |
tg->idletime_threshold = DFL_IDLE_THRESHOLD; tg->idletime_threshold_conf = DFL_IDLE_THRESHOLD; |
ec80991d6 blk-throttle: add... |
494 |
|
4fb72036f blk-throttle: rem... |
495 |
return &tg->pd; |
7ca464383 blk-throtl: stop ... |
496 497 498 499 500 501 |
err_exit_stat_bytes: blkg_rwstat_exit(&tg->stat_bytes); err_free_tg: kfree(tg); return NULL; |
001bea73e blkcg: replace bl... |
502 |
} |
a9520cd6f blkcg: make blkcg... |
503 |
static void throtl_pd_init(struct blkg_policy_data *pd) |
a29a171e7 blk-throttle: Do ... |
504 |
{ |
a9520cd6f blkcg: make blkcg... |
505 506 |
struct throtl_grp *tg = pd_to_tg(pd); struct blkcg_gq *blkg = tg_to_blkg(tg); |
77216b048 blk-throttle: add... |
507 |
struct throtl_data *td = blkg->q->td; |
b2ce2643c blk-throttle: cle... |
508 |
struct throtl_service_queue *sq = &tg->service_queue; |
cd1604fab blkcg: factor out... |
509 |
|
9138125be blk-throttle: imp... |
510 |
/* |
aa6ec29be cgroup: remove sa... |
511 |
* If on the default hierarchy, we switch to properly hierarchical |
9138125be blk-throttle: imp... |
512 513 514 515 516 |
* behavior where limits on a given throtl_grp are applied to the * whole subtree rather than just the group itself. e.g. If 16M * read_bps limit is set on the root group, the whole system can't * exceed 16M for the device. * |
aa6ec29be cgroup: remove sa... |
517 |
* If not on the default hierarchy, the broken flat hierarchy |
9138125be blk-throttle: imp... |
518 519 520 521 522 |
* behavior is retained where all throtl_grps are treated as if * they're all separate root groups right below throtl_data. * Limits of a group don't interact with limits of other groups * regardless of the position of the group in the hierarchy. */ |
b2ce2643c blk-throttle: cle... |
523 |
sq->parent_sq = &td->service_queue; |
9e10a130d cgroup: replace c... |
524 |
if (cgroup_subsys_on_dfl(io_cgrp_subsys) && blkg->parent) |
b2ce2643c blk-throttle: cle... |
525 |
sq->parent_sq = &blkg_to_tg(blkg->parent)->service_queue; |
77216b048 blk-throttle: add... |
526 |
tg->td = td; |
8a3d26151 blkcg: move blkio... |
527 |
} |
693e751e7 blk-throttle: imp... |
528 529 530 531 532 533 534 535 |
/* * Set has_rules[] if @tg or any of its parents have limits configured. * This doesn't require walking up to the top of the hierarchy as the * parent's has_rules[] is guaranteed to be correct. */ static void tg_update_has_rules(struct throtl_grp *tg) { struct throtl_grp *parent_tg = sq_to_tg(tg->service_queue.parent_sq); |
9f626e372 blk-throttle: pre... |
536 |
struct throtl_data *td = tg->td; |
693e751e7 blk-throttle: imp... |
537 538 539 540 |
int rw; for (rw = READ; rw <= WRITE; rw++) tg->has_rules[rw] = (parent_tg && parent_tg->has_rules[rw]) || |
9f626e372 blk-throttle: pre... |
541 542 543 |
(td->limit_valid[td->limit_index] && (tg_bps_limit(tg, rw) != U64_MAX || tg_iops_limit(tg, rw) != UINT_MAX)); |
693e751e7 blk-throttle: imp... |
544 |
} |
a9520cd6f blkcg: make blkcg... |
545 |
static void throtl_pd_online(struct blkg_policy_data *pd) |
693e751e7 blk-throttle: imp... |
546 |
{ |
aec242468 blk-throttle: det... |
547 |
struct throtl_grp *tg = pd_to_tg(pd); |
693e751e7 blk-throttle: imp... |
548 549 550 551 |
/* * We don't want new groups to escape the limits of its ancestors. * Update has_rules[] after a new group is brought online. */ |
aec242468 blk-throttle: det... |
552 |
tg_update_has_rules(tg); |
693e751e7 blk-throttle: imp... |
553 |
} |
cd5ab1b0f blk-throttle: add... |
554 555 556 557 558 559 560 561 562 563 564 |
static void blk_throtl_update_limit_valid(struct throtl_data *td) { struct cgroup_subsys_state *pos_css; struct blkcg_gq *blkg; bool low_valid = false; rcu_read_lock(); blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); if (tg->bps[READ][LIMIT_LOW] || tg->bps[WRITE][LIMIT_LOW] || |
43ada7878 Block: blk-thrott... |
565 |
tg->iops[READ][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) { |
cd5ab1b0f blk-throttle: add... |
566 |
low_valid = true; |
43ada7878 Block: blk-thrott... |
567 568 |
break; } |
cd5ab1b0f blk-throttle: add... |
569 570 571 572 573 |
} rcu_read_unlock(); td->limit_valid[LIMIT_LOW] = low_valid; } |
c79892c55 blk-throttle: add... |
574 |
static void throtl_upgrade_state(struct throtl_data *td); |
cd5ab1b0f blk-throttle: add... |
575 576 577 578 579 580 581 582 583 584 |
static void throtl_pd_offline(struct blkg_policy_data *pd) { struct throtl_grp *tg = pd_to_tg(pd); tg->bps[READ][LIMIT_LOW] = 0; tg->bps[WRITE][LIMIT_LOW] = 0; tg->iops[READ][LIMIT_LOW] = 0; tg->iops[WRITE][LIMIT_LOW] = 0; blk_throtl_update_limit_valid(tg->td); |
c79892c55 blk-throttle: add... |
585 586 |
if (!tg->td->limit_valid[tg->td->limit_index]) throtl_upgrade_state(tg->td); |
cd5ab1b0f blk-throttle: add... |
587 |
} |
001bea73e blkcg: replace bl... |
588 589 |
static void throtl_pd_free(struct blkg_policy_data *pd) { |
4fb72036f blk-throttle: rem... |
590 |
struct throtl_grp *tg = pd_to_tg(pd); |
b2ce2643c blk-throttle: cle... |
591 |
del_timer_sync(&tg->service_queue.pending_timer); |
7ca464383 blk-throtl: stop ... |
592 593 |
blkg_rwstat_exit(&tg->stat_bytes); blkg_rwstat_exit(&tg->stat_ios); |
4fb72036f blk-throttle: rem... |
594 |
kfree(tg); |
001bea73e blkcg: replace bl... |
595 |
} |
0049af73b blk-throttle: reo... |
596 597 |
static struct throtl_grp * throtl_rb_first(struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
598 |
{ |
9ff01255a Blk-throttle: upd... |
599 |
struct rb_node *n; |
e43473b7f blkio: Core imple... |
600 |
|
9ff01255a Blk-throttle: upd... |
601 602 603 604 605 |
n = rb_first_cached(&parent_sq->pending_tree); WARN_ON_ONCE(!n); if (!n) return NULL; return rb_entry_tg(n); |
e43473b7f blkio: Core imple... |
606 |
} |
0049af73b blk-throttle: reo... |
607 608 |
static void throtl_rb_erase(struct rb_node *n, struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
609 |
{ |
9ff01255a Blk-throttle: upd... |
610 611 |
rb_erase_cached(n, &parent_sq->pending_tree); RB_CLEAR_NODE(n); |
0049af73b blk-throttle: reo... |
612 |
--parent_sq->nr_pending; |
e43473b7f blkio: Core imple... |
613 |
} |
0049af73b blk-throttle: reo... |
614 |
static void update_min_dispatch_time(struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
615 616 |
{ struct throtl_grp *tg; |
0049af73b blk-throttle: reo... |
617 |
tg = throtl_rb_first(parent_sq); |
e43473b7f blkio: Core imple... |
618 619 |
if (!tg) return; |
0049af73b blk-throttle: reo... |
620 |
parent_sq->first_pending_disptime = tg->disptime; |
e43473b7f blkio: Core imple... |
621 |
} |
77216b048 blk-throttle: add... |
622 |
static void tg_service_queue_add(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
623 |
{ |
77216b048 blk-throttle: add... |
624 |
struct throtl_service_queue *parent_sq = tg->service_queue.parent_sq; |
9ff01255a Blk-throttle: upd... |
625 |
struct rb_node **node = &parent_sq->pending_tree.rb_root.rb_node; |
e43473b7f blkio: Core imple... |
626 627 628 |
struct rb_node *parent = NULL; struct throtl_grp *__tg; unsigned long key = tg->disptime; |
9ff01255a Blk-throttle: upd... |
629 |
bool leftmost = true; |
e43473b7f blkio: Core imple... |
630 631 632 633 634 635 636 637 638 |
while (*node != NULL) { parent = *node; __tg = rb_entry_tg(parent); if (time_before(key, __tg->disptime)) node = &parent->rb_left; else { node = &parent->rb_right; |
9ff01255a Blk-throttle: upd... |
639 |
leftmost = false; |
e43473b7f blkio: Core imple... |
640 641 |
} } |
e43473b7f blkio: Core imple... |
642 |
rb_link_node(&tg->rb_node, parent, node); |
9ff01255a Blk-throttle: upd... |
643 644 |
rb_insert_color_cached(&tg->rb_node, &parent_sq->pending_tree, leftmost); |
e43473b7f blkio: Core imple... |
645 |
} |
77216b048 blk-throttle: add... |
646 |
static void throtl_enqueue_tg(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
647 |
{ |
29379674b blk-throttle: Ope... |
648 649 650 651 652 |
if (!(tg->flags & THROTL_TG_PENDING)) { tg_service_queue_add(tg); tg->flags |= THROTL_TG_PENDING; tg->service_queue.parent_sq->nr_pending++; } |
e43473b7f blkio: Core imple... |
653 |
} |
77216b048 blk-throttle: add... |
654 |
static void throtl_dequeue_tg(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
655 |
{ |
29379674b blk-throttle: Ope... |
656 657 658 659 |
if (tg->flags & THROTL_TG_PENDING) { throtl_rb_erase(&tg->rb_node, tg->service_queue.parent_sq); tg->flags &= ~THROTL_TG_PENDING; } |
e43473b7f blkio: Core imple... |
660 |
} |
a9131a27e blk-throttle: rel... |
661 |
/* Call with queue lock held */ |
69df0ab03 blk-throttle: sep... |
662 663 |
static void throtl_schedule_pending_timer(struct throtl_service_queue *sq, unsigned long expires) |
a9131a27e blk-throttle: rel... |
664 |
{ |
a41b816c1 blk-throttle: fix... |
665 |
unsigned long max_expire = jiffies + 8 * sq_to_td(sq)->throtl_slice; |
06cceedcc blk-throttle: mak... |
666 667 668 669 670 671 672 673 674 675 |
/* * Since we are adjusting the throttle limit dynamically, the sleep * time calculated according to previous limit might be invalid. It's * possible the cgroup sleep time is very long and no other cgroups * have IO running so notify the limit changes. Make sure the cgroup * doesn't sleep too long to avoid the missed notification. */ if (time_after(expires, max_expire)) expires = max_expire; |
69df0ab03 blk-throttle: sep... |
676 677 678 |
mod_timer(&sq->pending_timer, expires); throtl_log(sq, "schedule timer. delay=%lu jiffies=%lu", expires - jiffies, jiffies); |
a9131a27e blk-throttle: rel... |
679 |
} |
7f52f98c2 blk-throttle: imp... |
680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 |
/** * throtl_schedule_next_dispatch - schedule the next dispatch cycle * @sq: the service_queue to schedule dispatch for * @force: force scheduling * * Arm @sq->pending_timer so that the next dispatch cycle starts on the * dispatch time of the first pending child. Returns %true if either timer * is armed or there's no pending child left. %false if the current * dispatch window is still open and the caller should continue * dispatching. * * If @force is %true, the dispatch timer is always scheduled and this * function is guaranteed to return %true. This is to be used when the * caller can't dispatch itself and needs to invoke pending_timer * unconditionally. Note that forced scheduling is likely to induce short * delay before dispatch starts even if @sq->first_pending_disptime is not * in the future and thus shouldn't be used in hot paths. */ static bool throtl_schedule_next_dispatch(struct throtl_service_queue *sq, bool force) |
e43473b7f blkio: Core imple... |
700 |
{ |
6a525600f blk-throttle: rem... |
701 |
/* any pending children left? */ |
c9e0332e8 blk-throttle: ren... |
702 |
if (!sq->nr_pending) |
7f52f98c2 blk-throttle: imp... |
703 |
return true; |
e43473b7f blkio: Core imple... |
704 |
|
c9e0332e8 blk-throttle: ren... |
705 |
update_min_dispatch_time(sq); |
e43473b7f blkio: Core imple... |
706 |
|
69df0ab03 blk-throttle: sep... |
707 |
/* is the next dispatch time in the future? */ |
7f52f98c2 blk-throttle: imp... |
708 |
if (force || time_after(sq->first_pending_disptime, jiffies)) { |
69df0ab03 blk-throttle: sep... |
709 |
throtl_schedule_pending_timer(sq, sq->first_pending_disptime); |
7f52f98c2 blk-throttle: imp... |
710 |
return true; |
69df0ab03 blk-throttle: sep... |
711 |
} |
7f52f98c2 blk-throttle: imp... |
712 713 |
/* tell the caller to continue dispatching */ return false; |
e43473b7f blkio: Core imple... |
714 |
} |
32ee5bc47 blk-throttle: Acc... |
715 716 717 718 719 720 721 722 723 724 725 726 727 728 |
static inline void throtl_start_new_slice_with_credit(struct throtl_grp *tg, bool rw, unsigned long start) { tg->bytes_disp[rw] = 0; tg->io_disp[rw] = 0; /* * Previous slice has expired. We must have trimmed it after last * bio dispatch. That means since start of last slice, we never used * that bandwidth. Do try to make use of that bandwidth while giving * credit. */ if (time_after_eq(start, tg->slice_start[rw])) tg->slice_start[rw] = start; |
297e3d854 blk-throttle: mak... |
729 |
tg->slice_end[rw] = jiffies + tg->td->throtl_slice; |
32ee5bc47 blk-throttle: Acc... |
730 731 732 733 734 |
throtl_log(&tg->service_queue, "[%c] new slice with credit start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', tg->slice_start[rw], tg->slice_end[rw], jiffies); } |
0f3457f60 blk-throttle: add... |
735 |
static inline void throtl_start_new_slice(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
736 737 |
{ tg->bytes_disp[rw] = 0; |
8e89d13f4 blkio: Implementa... |
738 |
tg->io_disp[rw] = 0; |
e43473b7f blkio: Core imple... |
739 |
tg->slice_start[rw] = jiffies; |
297e3d854 blk-throttle: mak... |
740 |
tg->slice_end[rw] = jiffies + tg->td->throtl_slice; |
fda6f272c blk-throttle: imp... |
741 742 743 744 |
throtl_log(&tg->service_queue, "[%c] new slice start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', tg->slice_start[rw], tg->slice_end[rw], jiffies); |
e43473b7f blkio: Core imple... |
745 |
} |
0f3457f60 blk-throttle: add... |
746 747 |
static inline void throtl_set_slice_end(struct throtl_grp *tg, bool rw, unsigned long jiffy_end) |
d1ae8ffdf blk-throttle: Tri... |
748 |
{ |
297e3d854 blk-throttle: mak... |
749 |
tg->slice_end[rw] = roundup(jiffy_end, tg->td->throtl_slice); |
d1ae8ffdf blk-throttle: Tri... |
750 |
} |
0f3457f60 blk-throttle: add... |
751 752 |
static inline void throtl_extend_slice(struct throtl_grp *tg, bool rw, unsigned long jiffy_end) |
e43473b7f blkio: Core imple... |
753 |
{ |
1da30f952 blk-throttle: Re-... |
754 |
throtl_set_slice_end(tg, rw, jiffy_end); |
fda6f272c blk-throttle: imp... |
755 756 757 758 |
throtl_log(&tg->service_queue, "[%c] extend slice start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', tg->slice_start[rw], tg->slice_end[rw], jiffies); |
e43473b7f blkio: Core imple... |
759 760 761 |
} /* Determine if previously allocated or extended slice is complete or not */ |
0f3457f60 blk-throttle: add... |
762 |
static bool throtl_slice_used(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
763 764 |
{ if (time_in_range(jiffies, tg->slice_start[rw], tg->slice_end[rw])) |
5cf8c2277 block/blk-throttl... |
765 |
return false; |
e43473b7f blkio: Core imple... |
766 |
|
0b6bad7d6 blk-throttle: ret... |
767 |
return true; |
e43473b7f blkio: Core imple... |
768 769 770 |
} /* Trim the used slices and adjust slice start accordingly */ |
0f3457f60 blk-throttle: add... |
771 |
static inline void throtl_trim_slice(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
772 |
{ |
3aad5d3ee blkio-throttle: F... |
773 774 |
unsigned long nr_slices, time_elapsed, io_trim; u64 bytes_trim, tmp; |
e43473b7f blkio: Core imple... |
775 776 777 778 779 780 781 782 |
BUG_ON(time_before(tg->slice_end[rw], tg->slice_start[rw])); /* * If bps are unlimited (-1), then time slice don't get * renewed. Don't try to trim the slice if slice is used. A new * slice will start when appropriate. */ |
0f3457f60 blk-throttle: add... |
783 |
if (throtl_slice_used(tg, rw)) |
e43473b7f blkio: Core imple... |
784 |
return; |
d1ae8ffdf blk-throttle: Tri... |
785 786 787 |
/* * A bio has been dispatched. Also adjust slice_end. It might happen * that initially cgroup limit was very low resulting in high |
b53b072c4 blk-throttle: Fix... |
788 |
* slice_end, but later limit was bumped up and bio was dispatched |
d1ae8ffdf blk-throttle: Tri... |
789 790 791 |
* sooner, then we need to reduce slice_end. A high bogus slice_end * is bad because it does not allow new slice to start. */ |
297e3d854 blk-throttle: mak... |
792 |
throtl_set_slice_end(tg, rw, jiffies + tg->td->throtl_slice); |
d1ae8ffdf blk-throttle: Tri... |
793 |
|
e43473b7f blkio: Core imple... |
794 |
time_elapsed = jiffies - tg->slice_start[rw]; |
297e3d854 blk-throttle: mak... |
795 |
nr_slices = time_elapsed / tg->td->throtl_slice; |
e43473b7f blkio: Core imple... |
796 797 798 |
if (!nr_slices) return; |
297e3d854 blk-throttle: mak... |
799 |
tmp = tg_bps_limit(tg, rw) * tg->td->throtl_slice * nr_slices; |
3aad5d3ee blkio-throttle: F... |
800 801 |
do_div(tmp, HZ); bytes_trim = tmp; |
e43473b7f blkio: Core imple... |
802 |
|
297e3d854 blk-throttle: mak... |
803 804 |
io_trim = (tg_iops_limit(tg, rw) * tg->td->throtl_slice * nr_slices) / HZ; |
e43473b7f blkio: Core imple... |
805 |
|
8e89d13f4 blkio: Implementa... |
806 |
if (!bytes_trim && !io_trim) |
e43473b7f blkio: Core imple... |
807 808 809 810 811 812 |
return; if (tg->bytes_disp[rw] >= bytes_trim) tg->bytes_disp[rw] -= bytes_trim; else tg->bytes_disp[rw] = 0; |
8e89d13f4 blkio: Implementa... |
813 814 815 816 |
if (tg->io_disp[rw] >= io_trim) tg->io_disp[rw] -= io_trim; else tg->io_disp[rw] = 0; |
297e3d854 blk-throttle: mak... |
817 |
tg->slice_start[rw] += nr_slices * tg->td->throtl_slice; |
e43473b7f blkio: Core imple... |
818 |
|
fda6f272c blk-throttle: imp... |
819 820 821 822 |
throtl_log(&tg->service_queue, "[%c] trim slice nr=%lu bytes=%llu io=%lu start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', nr_slices, bytes_trim, io_trim, tg->slice_start[rw], tg->slice_end[rw], jiffies); |
e43473b7f blkio: Core imple... |
823 |
} |
0f3457f60 blk-throttle: add... |
824 |
static bool tg_with_in_iops_limit(struct throtl_grp *tg, struct bio *bio, |
4599ea49d blk-throttle: Avo... |
825 |
u32 iops_limit, unsigned long *wait) |
e43473b7f blkio: Core imple... |
826 827 |
{ bool rw = bio_data_dir(bio); |
8e89d13f4 blkio: Implementa... |
828 |
unsigned int io_allowed; |
e43473b7f blkio: Core imple... |
829 |
unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd; |
c49c06e49 blkio-throttle: F... |
830 |
u64 tmp; |
e43473b7f blkio: Core imple... |
831 |
|
87fbeb881 blk-throttle: Avo... |
832 833 834 835 836 |
if (iops_limit == UINT_MAX) { if (wait) *wait = 0; return true; } |
3a10f999f blk-throttle: fix... |
837 |
jiffy_elapsed = jiffies - tg->slice_start[rw]; |
e43473b7f blkio: Core imple... |
838 |
|
3a10f999f blk-throttle: fix... |
839 840 |
/* Round up to the next throttle slice, wait time must be nonzero */ jiffy_elapsed_rnd = roundup(jiffy_elapsed + 1, tg->td->throtl_slice); |
8e89d13f4 blkio: Implementa... |
841 |
|
c49c06e49 blkio-throttle: F... |
842 843 844 845 846 847 |
/* * jiffy_elapsed_rnd should not be a big value as minimum iops can be * 1 then at max jiffy elapsed should be equivalent of 1 second as we * will allow dispatch after 1 second and after that slice should * have been trimmed. */ |
4599ea49d blk-throttle: Avo... |
848 |
tmp = (u64)iops_limit * jiffy_elapsed_rnd; |
c49c06e49 blkio-throttle: F... |
849 850 851 852 853 854 |
do_div(tmp, HZ); if (tmp > UINT_MAX) io_allowed = UINT_MAX; else io_allowed = tmp; |
8e89d13f4 blkio: Implementa... |
855 856 |
if (tg->io_disp[rw] + 1 <= io_allowed) { |
e43473b7f blkio: Core imple... |
857 858 |
if (wait) *wait = 0; |
5cf8c2277 block/blk-throttl... |
859 |
return true; |
e43473b7f blkio: Core imple... |
860 |
} |
8e89d13f4 blkio: Implementa... |
861 |
/* Calc approx time to dispatch */ |
991f61fe7 Blk-throttle: red... |
862 |
jiffy_wait = jiffy_elapsed_rnd - jiffy_elapsed; |
8e89d13f4 blkio: Implementa... |
863 864 865 |
if (wait) *wait = jiffy_wait; |
0b6bad7d6 blk-throttle: ret... |
866 |
return false; |
8e89d13f4 blkio: Implementa... |
867 |
} |
0f3457f60 blk-throttle: add... |
868 |
static bool tg_with_in_bps_limit(struct throtl_grp *tg, struct bio *bio, |
4599ea49d blk-throttle: Avo... |
869 |
u64 bps_limit, unsigned long *wait) |
8e89d13f4 blkio: Implementa... |
870 871 |
{ bool rw = bio_data_dir(bio); |
3aad5d3ee blkio-throttle: F... |
872 |
u64 bytes_allowed, extra_bytes, tmp; |
8e89d13f4 blkio: Implementa... |
873 |
unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd; |
ea0ea2bc6 blk-throttle: cap... |
874 |
unsigned int bio_size = throtl_bio_data_size(bio); |
e43473b7f blkio: Core imple... |
875 |
|
87fbeb881 blk-throttle: Avo... |
876 877 878 879 880 |
if (bps_limit == U64_MAX) { if (wait) *wait = 0; return true; } |
e43473b7f blkio: Core imple... |
881 882 883 884 |
jiffy_elapsed = jiffy_elapsed_rnd = jiffies - tg->slice_start[rw]; /* Slice has just started. Consider one slice interval */ if (!jiffy_elapsed) |
297e3d854 blk-throttle: mak... |
885 |
jiffy_elapsed_rnd = tg->td->throtl_slice; |
e43473b7f blkio: Core imple... |
886 |
|
297e3d854 blk-throttle: mak... |
887 |
jiffy_elapsed_rnd = roundup(jiffy_elapsed_rnd, tg->td->throtl_slice); |
e43473b7f blkio: Core imple... |
888 |
|
4599ea49d blk-throttle: Avo... |
889 |
tmp = bps_limit * jiffy_elapsed_rnd; |
5e901a2b9 blkio-throttle: T... |
890 |
do_div(tmp, HZ); |
3aad5d3ee blkio-throttle: F... |
891 |
bytes_allowed = tmp; |
e43473b7f blkio: Core imple... |
892 |
|
ea0ea2bc6 blk-throttle: cap... |
893 |
if (tg->bytes_disp[rw] + bio_size <= bytes_allowed) { |
e43473b7f blkio: Core imple... |
894 895 |
if (wait) *wait = 0; |
5cf8c2277 block/blk-throttl... |
896 |
return true; |
e43473b7f blkio: Core imple... |
897 898 899 |
} /* Calc approx time to dispatch */ |
ea0ea2bc6 blk-throttle: cap... |
900 |
extra_bytes = tg->bytes_disp[rw] + bio_size - bytes_allowed; |
4599ea49d blk-throttle: Avo... |
901 |
jiffy_wait = div64_u64(extra_bytes * HZ, bps_limit); |
e43473b7f blkio: Core imple... |
902 903 904 905 906 907 908 909 910 |
if (!jiffy_wait) jiffy_wait = 1; /* * This wait time is without taking into consideration the rounding * up we did. Add that time also. */ jiffy_wait = jiffy_wait + (jiffy_elapsed_rnd - jiffy_elapsed); |
e43473b7f blkio: Core imple... |
911 912 |
if (wait) *wait = jiffy_wait; |
0b6bad7d6 blk-throttle: ret... |
913 |
return false; |
8e89d13f4 blkio: Implementa... |
914 915 916 917 918 919 |
} /* * Returns whether one can dispatch a bio or not. Also returns approx number * of jiffies to wait before this bio is with-in IO rate and can be dispatched */ |
0f3457f60 blk-throttle: add... |
920 921 |
static bool tg_may_dispatch(struct throtl_grp *tg, struct bio *bio, unsigned long *wait) |
8e89d13f4 blkio: Implementa... |
922 923 924 |
{ bool rw = bio_data_dir(bio); unsigned long bps_wait = 0, iops_wait = 0, max_wait = 0; |
4599ea49d blk-throttle: Avo... |
925 926 |
u64 bps_limit = tg_bps_limit(tg, rw); u32 iops_limit = tg_iops_limit(tg, rw); |
8e89d13f4 blkio: Implementa... |
927 928 929 930 931 932 933 |
/* * Currently whole state machine of group depends on first bio * queued in the group bio list. So one should not be calling * this function with a different bio if there are other bios * queued. */ |
73f0d49a9 blk-throttle: mov... |
934 |
BUG_ON(tg->service_queue.nr_queued[rw] && |
c5cc2070b blk-throttle: add... |
935 |
bio != throtl_peek_queued(&tg->service_queue.queued[rw])); |
e43473b7f blkio: Core imple... |
936 |
|
8e89d13f4 blkio: Implementa... |
937 |
/* If tg->bps = -1, then BW is unlimited */ |
4599ea49d blk-throttle: Avo... |
938 |
if (bps_limit == U64_MAX && iops_limit == UINT_MAX) { |
8e89d13f4 blkio: Implementa... |
939 940 |
if (wait) *wait = 0; |
5cf8c2277 block/blk-throttl... |
941 |
return true; |
8e89d13f4 blkio: Implementa... |
942 943 944 945 946 |
} /* * If previous slice expired, start a new one otherwise renew/extend * existing slice to make sure it is at least throtl_slice interval |
164c80ed8 blk-throttle: Ext... |
947 948 949 |
* long since now. New slice is started only for empty throttle group. * If there is queued bio, that means there should be an active * slice and it should be extended instead. |
8e89d13f4 blkio: Implementa... |
950 |
*/ |
164c80ed8 blk-throttle: Ext... |
951 |
if (throtl_slice_used(tg, rw) && !(tg->service_queue.nr_queued[rw])) |
0f3457f60 blk-throttle: add... |
952 |
throtl_start_new_slice(tg, rw); |
8e89d13f4 blkio: Implementa... |
953 |
else { |
297e3d854 blk-throttle: mak... |
954 955 956 957 |
if (time_before(tg->slice_end[rw], jiffies + tg->td->throtl_slice)) throtl_extend_slice(tg, rw, jiffies + tg->td->throtl_slice); |
8e89d13f4 blkio: Implementa... |
958 |
} |
4599ea49d blk-throttle: Avo... |
959 960 |
if (tg_with_in_bps_limit(tg, bio, bps_limit, &bps_wait) && tg_with_in_iops_limit(tg, bio, iops_limit, &iops_wait)) { |
8e89d13f4 blkio: Implementa... |
961 962 |
if (wait) *wait = 0; |
0b6bad7d6 blk-throttle: ret... |
963 |
return true; |
8e89d13f4 blkio: Implementa... |
964 965 966 967 968 969 970 971 |
} max_wait = max(bps_wait, iops_wait); if (wait) *wait = max_wait; if (time_before(tg->slice_end[rw], jiffies + max_wait)) |
0f3457f60 blk-throttle: add... |
972 |
throtl_extend_slice(tg, rw, jiffies + max_wait); |
e43473b7f blkio: Core imple... |
973 |
|
0b6bad7d6 blk-throttle: ret... |
974 |
return false; |
e43473b7f blkio: Core imple... |
975 976 977 978 979 |
} static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio) { bool rw = bio_data_dir(bio); |
ea0ea2bc6 blk-throttle: cap... |
980 |
unsigned int bio_size = throtl_bio_data_size(bio); |
e43473b7f blkio: Core imple... |
981 982 |
/* Charge the bio to the group */ |
ea0ea2bc6 blk-throttle: cap... |
983 |
tg->bytes_disp[rw] += bio_size; |
8e89d13f4 blkio: Implementa... |
984 |
tg->io_disp[rw]++; |
ea0ea2bc6 blk-throttle: cap... |
985 |
tg->last_bytes_disp[rw] += bio_size; |
3f0abd806 blk-throttle: add... |
986 |
tg->last_io_disp[rw]++; |
e43473b7f blkio: Core imple... |
987 |
|
2a0f61e6e blk-throttle: set... |
988 |
/* |
8d2bbd4c8 block: replace RE... |
989 |
* BIO_THROTTLED is used to prevent the same bio to be throttled |
2a0f61e6e blk-throttle: set... |
990 991 992 |
* more than once as a throttled bio will go through blk-throtl the * second time when it eventually gets issued. Set it when a bio * is being charged to a tg. |
2a0f61e6e blk-throttle: set... |
993 |
*/ |
8d2bbd4c8 block: replace RE... |
994 995 |
if (!bio_flagged(bio, BIO_THROTTLED)) bio_set_flag(bio, BIO_THROTTLED); |
e43473b7f blkio: Core imple... |
996 |
} |
c5cc2070b blk-throttle: add... |
997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 |
/** * throtl_add_bio_tg - add a bio to the specified throtl_grp * @bio: bio to add * @qn: qnode to use * @tg: the target throtl_grp * * Add @bio to @tg's service_queue using @qn. If @qn is not specified, * tg->qnode_on_self[] is used. */ static void throtl_add_bio_tg(struct bio *bio, struct throtl_qnode *qn, struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
1008 |
{ |
73f0d49a9 blk-throttle: mov... |
1009 |
struct throtl_service_queue *sq = &tg->service_queue; |
e43473b7f blkio: Core imple... |
1010 |
bool rw = bio_data_dir(bio); |
c5cc2070b blk-throttle: add... |
1011 1012 |
if (!qn) qn = &tg->qnode_on_self[rw]; |
0e9f4164b blk-throttle: gen... |
1013 1014 1015 1016 |
/* * If @tg doesn't currently have any bios queued in the same * direction, queueing @bio can change when @tg should be * dispatched. Mark that @tg was empty. This is automatically |
b53b072c4 blk-throttle: Fix... |
1017 |
* cleared on the next tg_update_disptime(). |
0e9f4164b blk-throttle: gen... |
1018 1019 1020 |
*/ if (!sq->nr_queued[rw]) tg->flags |= THROTL_TG_WAS_EMPTY; |
c5cc2070b blk-throttle: add... |
1021 |
throtl_qnode_add_bio(bio, qn, &sq->queued[rw]); |
73f0d49a9 blk-throttle: mov... |
1022 |
sq->nr_queued[rw]++; |
77216b048 blk-throttle: add... |
1023 |
throtl_enqueue_tg(tg); |
e43473b7f blkio: Core imple... |
1024 |
} |
77216b048 blk-throttle: add... |
1025 |
static void tg_update_disptime(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
1026 |
{ |
73f0d49a9 blk-throttle: mov... |
1027 |
struct throtl_service_queue *sq = &tg->service_queue; |
e43473b7f blkio: Core imple... |
1028 1029 |
unsigned long read_wait = -1, write_wait = -1, min_wait = -1, disptime; struct bio *bio; |
d609af3a1 blk-throttle: Adj... |
1030 1031 |
bio = throtl_peek_queued(&sq->queued[READ]); if (bio) |
0f3457f60 blk-throttle: add... |
1032 |
tg_may_dispatch(tg, bio, &read_wait); |
e43473b7f blkio: Core imple... |
1033 |
|
d609af3a1 blk-throttle: Adj... |
1034 1035 |
bio = throtl_peek_queued(&sq->queued[WRITE]); if (bio) |
0f3457f60 blk-throttle: add... |
1036 |
tg_may_dispatch(tg, bio, &write_wait); |
e43473b7f blkio: Core imple... |
1037 1038 1039 |
min_wait = min(read_wait, write_wait); disptime = jiffies + min_wait; |
e43473b7f blkio: Core imple... |
1040 |
/* Update dispatch time */ |
77216b048 blk-throttle: add... |
1041 |
throtl_dequeue_tg(tg); |
e43473b7f blkio: Core imple... |
1042 |
tg->disptime = disptime; |
77216b048 blk-throttle: add... |
1043 |
throtl_enqueue_tg(tg); |
0e9f4164b blk-throttle: gen... |
1044 1045 1046 |
/* see throtl_add_bio_tg() */ tg->flags &= ~THROTL_TG_WAS_EMPTY; |
e43473b7f blkio: Core imple... |
1047 |
} |
32ee5bc47 blk-throttle: Acc... |
1048 1049 1050 1051 1052 1053 1054 1055 1056 |
static void start_parent_slice_with_credit(struct throtl_grp *child_tg, struct throtl_grp *parent_tg, bool rw) { if (throtl_slice_used(parent_tg, rw)) { throtl_start_new_slice_with_credit(parent_tg, rw, child_tg->slice_start[rw]); } } |
77216b048 blk-throttle: add... |
1057 |
static void tg_dispatch_one_bio(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
1058 |
{ |
73f0d49a9 blk-throttle: mov... |
1059 |
struct throtl_service_queue *sq = &tg->service_queue; |
6bc9c2b46 blk-throttle: mak... |
1060 1061 |
struct throtl_service_queue *parent_sq = sq->parent_sq; struct throtl_grp *parent_tg = sq_to_tg(parent_sq); |
c5cc2070b blk-throttle: add... |
1062 |
struct throtl_grp *tg_to_put = NULL; |
e43473b7f blkio: Core imple... |
1063 |
struct bio *bio; |
c5cc2070b blk-throttle: add... |
1064 1065 1066 1067 1068 1069 1070 |
/* * @bio is being transferred from @tg to @parent_sq. Popping a bio * from @tg may put its reference and @parent_sq might end up * getting released prematurely. Remember the tg to put and put it * after @bio is transferred to @parent_sq. */ bio = throtl_pop_queued(&sq->queued[rw], &tg_to_put); |
73f0d49a9 blk-throttle: mov... |
1071 |
sq->nr_queued[rw]--; |
e43473b7f blkio: Core imple... |
1072 1073 |
throtl_charge_bio(tg, bio); |
6bc9c2b46 blk-throttle: mak... |
1074 1075 1076 1077 1078 1079 1080 1081 1082 |
/* * If our parent is another tg, we just need to transfer @bio to * the parent using throtl_add_bio_tg(). If our parent is * @td->service_queue, @bio is ready to be issued. Put it on its * bio_lists[] and decrease total number queued. The caller is * responsible for issuing these bios. */ if (parent_tg) { |
c5cc2070b blk-throttle: add... |
1083 |
throtl_add_bio_tg(bio, &tg->qnode_on_parent[rw], parent_tg); |
32ee5bc47 blk-throttle: Acc... |
1084 |
start_parent_slice_with_credit(tg, parent_tg, rw); |
6bc9c2b46 blk-throttle: mak... |
1085 |
} else { |
c5cc2070b blk-throttle: add... |
1086 1087 |
throtl_qnode_add_bio(bio, &tg->qnode_on_parent[rw], &parent_sq->queued[rw]); |
6bc9c2b46 blk-throttle: mak... |
1088 1089 1090 |
BUG_ON(tg->td->nr_queued[rw] <= 0); tg->td->nr_queued[rw]--; } |
e43473b7f blkio: Core imple... |
1091 |
|
0f3457f60 blk-throttle: add... |
1092 |
throtl_trim_slice(tg, rw); |
6bc9c2b46 blk-throttle: mak... |
1093 |
|
c5cc2070b blk-throttle: add... |
1094 1095 |
if (tg_to_put) blkg_put(tg_to_blkg(tg_to_put)); |
e43473b7f blkio: Core imple... |
1096 |
} |
77216b048 blk-throttle: add... |
1097 |
static int throtl_dispatch_tg(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
1098 |
{ |
73f0d49a9 blk-throttle: mov... |
1099 |
struct throtl_service_queue *sq = &tg->service_queue; |
e43473b7f blkio: Core imple... |
1100 |
unsigned int nr_reads = 0, nr_writes = 0; |
e675df2ad blk-throttle: Def... |
1101 1102 |
unsigned int max_nr_reads = THROTL_GRP_QUANTUM * 3 / 4; unsigned int max_nr_writes = THROTL_GRP_QUANTUM - max_nr_reads; |
e43473b7f blkio: Core imple... |
1103 1104 1105 |
struct bio *bio; /* Try to dispatch 75% READS and 25% WRITES */ |
c5cc2070b blk-throttle: add... |
1106 |
while ((bio = throtl_peek_queued(&sq->queued[READ])) && |
0f3457f60 blk-throttle: add... |
1107 |
tg_may_dispatch(tg, bio, NULL)) { |
e43473b7f blkio: Core imple... |
1108 |
|
77216b048 blk-throttle: add... |
1109 |
tg_dispatch_one_bio(tg, bio_data_dir(bio)); |
e43473b7f blkio: Core imple... |
1110 1111 1112 1113 1114 |
nr_reads++; if (nr_reads >= max_nr_reads) break; } |
c5cc2070b blk-throttle: add... |
1115 |
while ((bio = throtl_peek_queued(&sq->queued[WRITE])) && |
0f3457f60 blk-throttle: add... |
1116 |
tg_may_dispatch(tg, bio, NULL)) { |
e43473b7f blkio: Core imple... |
1117 |
|
77216b048 blk-throttle: add... |
1118 |
tg_dispatch_one_bio(tg, bio_data_dir(bio)); |
e43473b7f blkio: Core imple... |
1119 1120 1121 1122 1123 1124 1125 1126 |
nr_writes++; if (nr_writes >= max_nr_writes) break; } return nr_reads + nr_writes; } |
651930bc1 blk-throttle: dis... |
1127 |
static int throtl_select_dispatch(struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
1128 1129 |
{ unsigned int nr_disp = 0; |
e43473b7f blkio: Core imple... |
1130 1131 |
while (1) { |
2397611ac blk-throttle: Mov... |
1132 |
struct throtl_grp *tg; |
2ab74cd29 blk-throttle: fix... |
1133 |
struct throtl_service_queue *sq; |
e43473b7f blkio: Core imple... |
1134 |
|
2397611ac blk-throttle: Mov... |
1135 1136 1137 1138 |
if (!parent_sq->nr_pending) break; tg = throtl_rb_first(parent_sq); |
e43473b7f blkio: Core imple... |
1139 1140 1141 1142 1143 |
if (!tg) break; if (time_before(jiffies, tg->disptime)) break; |
77216b048 blk-throttle: add... |
1144 |
throtl_dequeue_tg(tg); |
e43473b7f blkio: Core imple... |
1145 |
|
77216b048 blk-throttle: add... |
1146 |
nr_disp += throtl_dispatch_tg(tg); |
e43473b7f blkio: Core imple... |
1147 |
|
2ab74cd29 blk-throttle: fix... |
1148 |
sq = &tg->service_queue; |
73f0d49a9 blk-throttle: mov... |
1149 |
if (sq->nr_queued[0] || sq->nr_queued[1]) |
77216b048 blk-throttle: add... |
1150 |
tg_update_disptime(tg); |
e43473b7f blkio: Core imple... |
1151 |
|
e675df2ad blk-throttle: Def... |
1152 |
if (nr_disp >= THROTL_QUANTUM) |
e43473b7f blkio: Core imple... |
1153 1154 1155 1156 1157 |
break; } return nr_disp; } |
c79892c55 blk-throttle: add... |
1158 1159 |
static bool throtl_can_upgrade(struct throtl_data *td, struct throtl_grp *this_tg); |
6e1a5704c blk-throttle: dis... |
1160 1161 |
/** * throtl_pending_timer_fn - timer function for service_queue->pending_timer |
216382dcc block: Fix throtl... |
1162 |
* @t: the pending_timer member of the throtl_service_queue being serviced |
6e1a5704c blk-throttle: dis... |
1163 1164 1165 1166 |
* * This timer is armed when a child throtl_grp with active bio's become * pending and queued on the service_queue's pending_tree and expires when * the first child throtl_grp should be dispatched. This function |
2e48a530a blk-throttle: mak... |
1167 1168 1169 1170 1171 1172 1173 |
* dispatches bio's from the children throtl_grps to the parent * service_queue. * * If the parent's parent is another throtl_grp, dispatching is propagated * by either arming its pending_timer or repeating dispatch directly. If * the top-level service_tree is reached, throtl_data->dispatch_work is * kicked so that the ready bio's are issued. |
6e1a5704c blk-throttle: dis... |
1174 |
*/ |
e99e88a9d treewide: setup_t... |
1175 |
static void throtl_pending_timer_fn(struct timer_list *t) |
69df0ab03 blk-throttle: sep... |
1176 |
{ |
e99e88a9d treewide: setup_t... |
1177 |
struct throtl_service_queue *sq = from_timer(sq, t, pending_timer); |
2e48a530a blk-throttle: mak... |
1178 |
struct throtl_grp *tg = sq_to_tg(sq); |
69df0ab03 blk-throttle: sep... |
1179 |
struct throtl_data *td = sq_to_td(sq); |
cb76199c3 blk-throttle: col... |
1180 |
struct request_queue *q = td->queue; |
2e48a530a blk-throttle: mak... |
1181 1182 |
struct throtl_service_queue *parent_sq; bool dispatched; |
6e1a5704c blk-throttle: dis... |
1183 |
int ret; |
e43473b7f blkio: Core imple... |
1184 |
|
0d945c1f9 block: remove the... |
1185 |
spin_lock_irq(&q->queue_lock); |
c79892c55 blk-throttle: add... |
1186 1187 |
if (throtl_can_upgrade(td, NULL)) throtl_upgrade_state(td); |
2e48a530a blk-throttle: mak... |
1188 1189 1190 |
again: parent_sq = sq->parent_sq; dispatched = false; |
e43473b7f blkio: Core imple... |
1191 |
|
7f52f98c2 blk-throttle: imp... |
1192 1193 |
while (true) { throtl_log(sq, "dispatch nr_queued=%u read=%u write=%u", |
2e48a530a blk-throttle: mak... |
1194 1195 |
sq->nr_queued[READ] + sq->nr_queued[WRITE], sq->nr_queued[READ], sq->nr_queued[WRITE]); |
7f52f98c2 blk-throttle: imp... |
1196 1197 1198 |
ret = throtl_select_dispatch(sq); if (ret) { |
7f52f98c2 blk-throttle: imp... |
1199 1200 1201 |
throtl_log(sq, "bios disp=%u", ret); dispatched = true; } |
e43473b7f blkio: Core imple... |
1202 |
|
7f52f98c2 blk-throttle: imp... |
1203 1204 |
if (throtl_schedule_next_dispatch(sq, false)) break; |
e43473b7f blkio: Core imple... |
1205 |
|
7f52f98c2 blk-throttle: imp... |
1206 |
/* this dispatch windows is still open, relax and repeat */ |
0d945c1f9 block: remove the... |
1207 |
spin_unlock_irq(&q->queue_lock); |
7f52f98c2 blk-throttle: imp... |
1208 |
cpu_relax(); |
0d945c1f9 block: remove the... |
1209 |
spin_lock_irq(&q->queue_lock); |
651930bc1 blk-throttle: dis... |
1210 |
} |
e43473b7f blkio: Core imple... |
1211 |
|
2e48a530a blk-throttle: mak... |
1212 1213 |
if (!dispatched) goto out_unlock; |
6e1a5704c blk-throttle: dis... |
1214 |
|
2e48a530a blk-throttle: mak... |
1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 |
if (parent_sq) { /* @parent_sq is another throl_grp, propagate dispatch */ if (tg->flags & THROTL_TG_WAS_EMPTY) { tg_update_disptime(tg); if (!throtl_schedule_next_dispatch(parent_sq, false)) { /* window is already open, repeat dispatching */ sq = parent_sq; tg = sq_to_tg(sq); goto again; } } } else { |
b53b072c4 blk-throttle: Fix... |
1227 |
/* reached the top-level, queue issuing */ |
2e48a530a blk-throttle: mak... |
1228 1229 1230 |
queue_work(kthrotld_workqueue, &td->dispatch_work); } out_unlock: |
0d945c1f9 block: remove the... |
1231 |
spin_unlock_irq(&q->queue_lock); |
6e1a5704c blk-throttle: dis... |
1232 |
} |
e43473b7f blkio: Core imple... |
1233 |
|
6e1a5704c blk-throttle: dis... |
1234 1235 1236 1237 |
/** * blk_throtl_dispatch_work_fn - work function for throtl_data->dispatch_work * @work: work item being executed * |
b53b072c4 blk-throttle: Fix... |
1238 1239 |
* This function is queued for execution when bios reach the bio_lists[] * of throtl_data->service_queue. Those bios are ready and issued by this |
6e1a5704c blk-throttle: dis... |
1240 1241 |
* function. */ |
8876e140e block/blk-throttl... |
1242 |
static void blk_throtl_dispatch_work_fn(struct work_struct *work) |
6e1a5704c blk-throttle: dis... |
1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 |
{ struct throtl_data *td = container_of(work, struct throtl_data, dispatch_work); struct throtl_service_queue *td_sq = &td->service_queue; struct request_queue *q = td->queue; struct bio_list bio_list_on_stack; struct bio *bio; struct blk_plug plug; int rw; bio_list_init(&bio_list_on_stack); |
0d945c1f9 block: remove the... |
1254 |
spin_lock_irq(&q->queue_lock); |
c5cc2070b blk-throttle: add... |
1255 1256 1257 |
for (rw = READ; rw <= WRITE; rw++) while ((bio = throtl_pop_queued(&td_sq->queued[rw], NULL))) bio_list_add(&bio_list_on_stack, bio); |
0d945c1f9 block: remove the... |
1258 |
spin_unlock_irq(&q->queue_lock); |
6e1a5704c blk-throttle: dis... |
1259 1260 |
if (!bio_list_empty(&bio_list_on_stack)) { |
69d60eb96 blk-throttle: Use... |
1261 |
blk_start_plug(&plug); |
ed00aabd5 block: rename gen... |
1262 1263 |
while ((bio = bio_list_pop(&bio_list_on_stack))) submit_bio_noacct(bio); |
69d60eb96 blk-throttle: Use... |
1264 |
blk_finish_plug(&plug); |
e43473b7f blkio: Core imple... |
1265 |
} |
e43473b7f blkio: Core imple... |
1266 |
} |
f95a04afa blkcg: embed stru... |
1267 1268 |
static u64 tg_prfill_conf_u64(struct seq_file *sf, struct blkg_policy_data *pd, int off) |
60c2bc2d5 blkcg: move conf/... |
1269 |
{ |
f95a04afa blkcg: embed stru... |
1270 1271 |
struct throtl_grp *tg = pd_to_tg(pd); u64 v = *(u64 *)((void *)tg + off); |
60c2bc2d5 blkcg: move conf/... |
1272 |
|
2ab5492de blk-throttle: use... |
1273 |
if (v == U64_MAX) |
60c2bc2d5 blkcg: move conf/... |
1274 |
return 0; |
f95a04afa blkcg: embed stru... |
1275 |
return __blkg_prfill_u64(sf, pd, v); |
60c2bc2d5 blkcg: move conf/... |
1276 |
} |
f95a04afa blkcg: embed stru... |
1277 1278 |
static u64 tg_prfill_conf_uint(struct seq_file *sf, struct blkg_policy_data *pd, int off) |
e43473b7f blkio: Core imple... |
1279 |
{ |
f95a04afa blkcg: embed stru... |
1280 1281 |
struct throtl_grp *tg = pd_to_tg(pd); unsigned int v = *(unsigned int *)((void *)tg + off); |
fe0714377 blkio: Recalculat... |
1282 |
|
2ab5492de blk-throttle: use... |
1283 |
if (v == UINT_MAX) |
af133ceb2 blkcg: move blkio... |
1284 |
return 0; |
f95a04afa blkcg: embed stru... |
1285 |
return __blkg_prfill_u64(sf, pd, v); |
e43473b7f blkio: Core imple... |
1286 |
} |
2da8ca822 cgroup: replace c... |
1287 |
static int tg_print_conf_u64(struct seq_file *sf, void *v) |
8e89d13f4 blkio: Implementa... |
1288 |
{ |
2da8ca822 cgroup: replace c... |
1289 1290 |
blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_u64, &blkcg_policy_throtl, seq_cft(sf)->private, false); |
af133ceb2 blkcg: move blkio... |
1291 |
return 0; |
8e89d13f4 blkio: Implementa... |
1292 |
} |
2da8ca822 cgroup: replace c... |
1293 |
static int tg_print_conf_uint(struct seq_file *sf, void *v) |
8e89d13f4 blkio: Implementa... |
1294 |
{ |
2da8ca822 cgroup: replace c... |
1295 1296 |
blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_uint, &blkcg_policy_throtl, seq_cft(sf)->private, false); |
af133ceb2 blkcg: move blkio... |
1297 |
return 0; |
60c2bc2d5 blkcg: move conf/... |
1298 |
} |
9bb67aeb9 blk-throttle: res... |
1299 |
static void tg_conf_updated(struct throtl_grp *tg, bool global) |
60c2bc2d5 blkcg: move conf/... |
1300 |
{ |
69948b070 blkcg: separate o... |
1301 |
struct throtl_service_queue *sq = &tg->service_queue; |
492eb21b9 cgroup: make hier... |
1302 |
struct cgroup_subsys_state *pos_css; |
69948b070 blkcg: separate o... |
1303 |
struct blkcg_gq *blkg; |
af133ceb2 blkcg: move blkio... |
1304 |
|
fda6f272c blk-throttle: imp... |
1305 1306 |
throtl_log(&tg->service_queue, "limit change rbps=%llu wbps=%llu riops=%u wiops=%u", |
9f626e372 blk-throttle: pre... |
1307 1308 |
tg_bps_limit(tg, READ), tg_bps_limit(tg, WRITE), tg_iops_limit(tg, READ), tg_iops_limit(tg, WRITE)); |
632b44935 blk-throttle: rem... |
1309 1310 |
/* |
693e751e7 blk-throttle: imp... |
1311 1312 1313 1314 1315 1316 |
* Update has_rules[] flags for the updated tg's subtree. A tg is * considered to have rules if either the tg itself or any of its * ancestors has rules. This identifies groups without any * restrictions in the whole hierarchy and allows them to bypass * blk-throttle. */ |
9bb67aeb9 blk-throttle: res... |
1317 1318 |
blkg_for_each_descendant_pre(blkg, pos_css, global ? tg->td->queue->root_blkg : tg_to_blkg(tg)) { |
5b81fc3cc blk-throttle: add... |
1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 |
struct throtl_grp *this_tg = blkg_to_tg(blkg); struct throtl_grp *parent_tg; tg_update_has_rules(this_tg); /* ignore root/second level */ if (!cgroup_subsys_on_dfl(io_cgrp_subsys) || !blkg->parent || !blkg->parent->parent) continue; parent_tg = blkg_to_tg(blkg->parent); /* * make sure all children has lower idle time threshold and * higher latency target */ this_tg->idletime_threshold = min(this_tg->idletime_threshold, parent_tg->idletime_threshold); this_tg->latency_target = max(this_tg->latency_target, parent_tg->latency_target); } |
693e751e7 blk-throttle: imp... |
1337 1338 |
/* |
632b44935 blk-throttle: rem... |
1339 1340 1341 1342 1343 1344 1345 |
* We're already holding queue_lock and know @tg is valid. Let's * apply the new config directly. * * Restart the slices for both READ and WRITES. It might happen * that a group's limit are dropped suddenly and we don't want to * account recently dispatched IO with new low rate. */ |
ff8b22c0f blk-throttle: Use... |
1346 1347 |
throtl_start_new_slice(tg, READ); throtl_start_new_slice(tg, WRITE); |
632b44935 blk-throttle: rem... |
1348 |
|
5b2c16aae blk-throttle: sim... |
1349 |
if (tg->flags & THROTL_TG_PENDING) { |
77216b048 blk-throttle: add... |
1350 |
tg_update_disptime(tg); |
7f52f98c2 blk-throttle: imp... |
1351 |
throtl_schedule_next_dispatch(sq->parent_sq, true); |
632b44935 blk-throttle: rem... |
1352 |
} |
69948b070 blkcg: separate o... |
1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 |
} static ssize_t tg_set_conf(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off, bool is_u64) { struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct throtl_grp *tg; int ret; u64 v; ret = blkg_conf_prep(blkcg, &blkcg_policy_throtl, buf, &ctx); if (ret) return ret; ret = -EINVAL; if (sscanf(ctx.body, "%llu", &v) != 1) goto out_finish; if (!v) |
2ab5492de blk-throttle: use... |
1372 |
v = U64_MAX; |
69948b070 blkcg: separate o... |
1373 1374 1375 1376 1377 1378 1379 |
tg = blkg_to_tg(ctx.blkg); if (is_u64) *(u64 *)((void *)tg + of_cft(of)->private) = v; else *(unsigned int *)((void *)tg + of_cft(of)->private) = v; |
60c2bc2d5 blkcg: move conf/... |
1380 |
|
9bb67aeb9 blk-throttle: res... |
1381 |
tg_conf_updated(tg, false); |
36aa9e5f5 blkcg: move body ... |
1382 1383 |
ret = 0; out_finish: |
60c2bc2d5 blkcg: move conf/... |
1384 |
blkg_conf_finish(&ctx); |
36aa9e5f5 blkcg: move body ... |
1385 |
return ret ?: nbytes; |
8e89d13f4 blkio: Implementa... |
1386 |
} |
451af504d cgroup: replace c... |
1387 1388 |
static ssize_t tg_set_conf_u64(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) |
60c2bc2d5 blkcg: move conf/... |
1389 |
{ |
451af504d cgroup: replace c... |
1390 |
return tg_set_conf(of, buf, nbytes, off, true); |
60c2bc2d5 blkcg: move conf/... |
1391 |
} |
451af504d cgroup: replace c... |
1392 1393 |
static ssize_t tg_set_conf_uint(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) |
60c2bc2d5 blkcg: move conf/... |
1394 |
{ |
451af504d cgroup: replace c... |
1395 |
return tg_set_conf(of, buf, nbytes, off, false); |
60c2bc2d5 blkcg: move conf/... |
1396 |
} |
7ca464383 blk-throtl: stop ... |
1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 |
static int tg_print_rwstat(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat, &blkcg_policy_throtl, seq_cft(sf)->private, true); return 0; } static u64 tg_prfill_rwstat_recursive(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct blkg_rwstat_sample sum; blkg_rwstat_recursive_sum(pd_to_blkg(pd), &blkcg_policy_throtl, off, &sum); return __blkg_prfill_rwstat(sf, pd, &sum); } static int tg_print_rwstat_recursive(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_rwstat_recursive, &blkcg_policy_throtl, seq_cft(sf)->private, true); return 0; } |
880f50e22 blkcg: mark exist... |
1422 |
static struct cftype throtl_legacy_files[] = { |
60c2bc2d5 blkcg: move conf/... |
1423 1424 |
{ .name = "throttle.read_bps_device", |
9f626e372 blk-throttle: pre... |
1425 |
.private = offsetof(struct throtl_grp, bps[READ][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1426 |
.seq_show = tg_print_conf_u64, |
451af504d cgroup: replace c... |
1427 |
.write = tg_set_conf_u64, |
60c2bc2d5 blkcg: move conf/... |
1428 1429 1430 |
}, { .name = "throttle.write_bps_device", |
9f626e372 blk-throttle: pre... |
1431 |
.private = offsetof(struct throtl_grp, bps[WRITE][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1432 |
.seq_show = tg_print_conf_u64, |
451af504d cgroup: replace c... |
1433 |
.write = tg_set_conf_u64, |
60c2bc2d5 blkcg: move conf/... |
1434 1435 1436 |
}, { .name = "throttle.read_iops_device", |
9f626e372 blk-throttle: pre... |
1437 |
.private = offsetof(struct throtl_grp, iops[READ][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1438 |
.seq_show = tg_print_conf_uint, |
451af504d cgroup: replace c... |
1439 |
.write = tg_set_conf_uint, |
60c2bc2d5 blkcg: move conf/... |
1440 1441 1442 |
}, { .name = "throttle.write_iops_device", |
9f626e372 blk-throttle: pre... |
1443 |
.private = offsetof(struct throtl_grp, iops[WRITE][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1444 |
.seq_show = tg_print_conf_uint, |
451af504d cgroup: replace c... |
1445 |
.write = tg_set_conf_uint, |
60c2bc2d5 blkcg: move conf/... |
1446 1447 1448 |
}, { .name = "throttle.io_service_bytes", |
7ca464383 blk-throtl: stop ... |
1449 1450 |
.private = offsetof(struct throtl_grp, stat_bytes), .seq_show = tg_print_rwstat, |
60c2bc2d5 blkcg: move conf/... |
1451 1452 |
}, { |
17534c6f2 blk-throttle: exp... |
1453 |
.name = "throttle.io_service_bytes_recursive", |
7ca464383 blk-throtl: stop ... |
1454 1455 |
.private = offsetof(struct throtl_grp, stat_bytes), .seq_show = tg_print_rwstat_recursive, |
17534c6f2 blk-throttle: exp... |
1456 1457 |
}, { |
60c2bc2d5 blkcg: move conf/... |
1458 |
.name = "throttle.io_serviced", |
7ca464383 blk-throtl: stop ... |
1459 1460 |
.private = offsetof(struct throtl_grp, stat_ios), .seq_show = tg_print_rwstat, |
60c2bc2d5 blkcg: move conf/... |
1461 |
}, |
17534c6f2 blk-throttle: exp... |
1462 1463 |
{ .name = "throttle.io_serviced_recursive", |
7ca464383 blk-throtl: stop ... |
1464 1465 |
.private = offsetof(struct throtl_grp, stat_ios), .seq_show = tg_print_rwstat_recursive, |
17534c6f2 blk-throttle: exp... |
1466 |
}, |
60c2bc2d5 blkcg: move conf/... |
1467 1468 |
{ } /* terminate */ }; |
cd5ab1b0f blk-throttle: add... |
1469 |
static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd, |
2ee867dcf blkcg: implement ... |
1470 1471 1472 1473 1474 |
int off) { struct throtl_grp *tg = pd_to_tg(pd); const char *dname = blkg_dev_name(pd->blkg); char bufs[4][21] = { "max", "max", "max", "max" }; |
cd5ab1b0f blk-throttle: add... |
1475 1476 |
u64 bps_dft; unsigned int iops_dft; |
ada75b6e5 blk-throttle: add... |
1477 |
char idle_time[26] = ""; |
ec80991d6 blk-throttle: add... |
1478 |
char latency_time[26] = ""; |
2ee867dcf blkcg: implement ... |
1479 1480 1481 |
if (!dname) return 0; |
9f626e372 blk-throttle: pre... |
1482 |
|
cd5ab1b0f blk-throttle: add... |
1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 |
if (off == LIMIT_LOW) { bps_dft = 0; iops_dft = 0; } else { bps_dft = U64_MAX; iops_dft = UINT_MAX; } if (tg->bps_conf[READ][off] == bps_dft && tg->bps_conf[WRITE][off] == bps_dft && tg->iops_conf[READ][off] == iops_dft && |
ada75b6e5 blk-throttle: add... |
1494 |
tg->iops_conf[WRITE][off] == iops_dft && |
ec80991d6 blk-throttle: add... |
1495 |
(off != LIMIT_LOW || |
b4f428ef2 blk-throttle: for... |
1496 |
(tg->idletime_threshold_conf == DFL_IDLE_THRESHOLD && |
5b81fc3cc blk-throttle: add... |
1497 |
tg->latency_target_conf == DFL_LATENCY_TARGET))) |
2ee867dcf blkcg: implement ... |
1498 |
return 0; |
9bb67aeb9 blk-throttle: res... |
1499 |
if (tg->bps_conf[READ][off] != U64_MAX) |
9f626e372 blk-throttle: pre... |
1500 |
snprintf(bufs[0], sizeof(bufs[0]), "%llu", |
cd5ab1b0f blk-throttle: add... |
1501 |
tg->bps_conf[READ][off]); |
9bb67aeb9 blk-throttle: res... |
1502 |
if (tg->bps_conf[WRITE][off] != U64_MAX) |
9f626e372 blk-throttle: pre... |
1503 |
snprintf(bufs[1], sizeof(bufs[1]), "%llu", |
cd5ab1b0f blk-throttle: add... |
1504 |
tg->bps_conf[WRITE][off]); |
9bb67aeb9 blk-throttle: res... |
1505 |
if (tg->iops_conf[READ][off] != UINT_MAX) |
9f626e372 blk-throttle: pre... |
1506 |
snprintf(bufs[2], sizeof(bufs[2]), "%u", |
cd5ab1b0f blk-throttle: add... |
1507 |
tg->iops_conf[READ][off]); |
9bb67aeb9 blk-throttle: res... |
1508 |
if (tg->iops_conf[WRITE][off] != UINT_MAX) |
9f626e372 blk-throttle: pre... |
1509 |
snprintf(bufs[3], sizeof(bufs[3]), "%u", |
cd5ab1b0f blk-throttle: add... |
1510 |
tg->iops_conf[WRITE][off]); |
ada75b6e5 blk-throttle: add... |
1511 |
if (off == LIMIT_LOW) { |
5b81fc3cc blk-throttle: add... |
1512 |
if (tg->idletime_threshold_conf == ULONG_MAX) |
ada75b6e5 blk-throttle: add... |
1513 1514 1515 |
strcpy(idle_time, " idle=max"); else snprintf(idle_time, sizeof(idle_time), " idle=%lu", |
5b81fc3cc blk-throttle: add... |
1516 |
tg->idletime_threshold_conf); |
ec80991d6 blk-throttle: add... |
1517 |
|
5b81fc3cc blk-throttle: add... |
1518 |
if (tg->latency_target_conf == ULONG_MAX) |
ec80991d6 blk-throttle: add... |
1519 1520 1521 |
strcpy(latency_time, " latency=max"); else snprintf(latency_time, sizeof(latency_time), |
5b81fc3cc blk-throttle: add... |
1522 |
" latency=%lu", tg->latency_target_conf); |
ada75b6e5 blk-throttle: add... |
1523 |
} |
2ee867dcf blkcg: implement ... |
1524 |
|
ec80991d6 blk-throttle: add... |
1525 1526 1527 1528 |
seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s%s%s ", dname, bufs[0], bufs[1], bufs[2], bufs[3], idle_time, latency_time); |
2ee867dcf blkcg: implement ... |
1529 1530 |
return 0; } |
cd5ab1b0f blk-throttle: add... |
1531 |
static int tg_print_limit(struct seq_file *sf, void *v) |
2ee867dcf blkcg: implement ... |
1532 |
{ |
cd5ab1b0f blk-throttle: add... |
1533 |
blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_limit, |
2ee867dcf blkcg: implement ... |
1534 1535 1536 |
&blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } |
cd5ab1b0f blk-throttle: add... |
1537 |
static ssize_t tg_set_limit(struct kernfs_open_file *of, |
2ee867dcf blkcg: implement ... |
1538 1539 1540 1541 1542 1543 |
char *buf, size_t nbytes, loff_t off) { struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct throtl_grp *tg; u64 v[4]; |
ada75b6e5 blk-throttle: add... |
1544 |
unsigned long idle_time; |
ec80991d6 blk-throttle: add... |
1545 |
unsigned long latency_time; |
2ee867dcf blkcg: implement ... |
1546 |
int ret; |
cd5ab1b0f blk-throttle: add... |
1547 |
int index = of_cft(of)->private; |
2ee867dcf blkcg: implement ... |
1548 1549 1550 1551 1552 1553 |
ret = blkg_conf_prep(blkcg, &blkcg_policy_throtl, buf, &ctx); if (ret) return ret; tg = blkg_to_tg(ctx.blkg); |
cd5ab1b0f blk-throttle: add... |
1554 1555 1556 1557 |
v[0] = tg->bps_conf[READ][index]; v[1] = tg->bps_conf[WRITE][index]; v[2] = tg->iops_conf[READ][index]; v[3] = tg->iops_conf[WRITE][index]; |
2ee867dcf blkcg: implement ... |
1558 |
|
5b81fc3cc blk-throttle: add... |
1559 1560 |
idle_time = tg->idletime_threshold_conf; latency_time = tg->latency_target_conf; |
2ee867dcf blkcg: implement ... |
1561 1562 1563 |
while (true) { char tok[27]; /* wiops=18446744073709551616 */ char *p; |
2ab5492de blk-throttle: use... |
1564 |
u64 val = U64_MAX; |
2ee867dcf blkcg: implement ... |
1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 |
int len; if (sscanf(ctx.body, "%26s%n", tok, &len) != 1) break; if (tok[0] == '\0') break; ctx.body += len; ret = -EINVAL; p = tok; strsep(&p, "="); if (!p || (sscanf(p, "%llu", &val) != 1 && strcmp(p, "max"))) goto out_finish; ret = -ERANGE; if (!val) goto out_finish; ret = -EINVAL; |
5b7048b89 blk-throttle: Fix... |
1584 |
if (!strcmp(tok, "rbps") && val > 1) |
2ee867dcf blkcg: implement ... |
1585 |
v[0] = val; |
5b7048b89 blk-throttle: Fix... |
1586 |
else if (!strcmp(tok, "wbps") && val > 1) |
2ee867dcf blkcg: implement ... |
1587 |
v[1] = val; |
5b7048b89 blk-throttle: Fix... |
1588 |
else if (!strcmp(tok, "riops") && val > 1) |
2ee867dcf blkcg: implement ... |
1589 |
v[2] = min_t(u64, val, UINT_MAX); |
5b7048b89 blk-throttle: Fix... |
1590 |
else if (!strcmp(tok, "wiops") && val > 1) |
2ee867dcf blkcg: implement ... |
1591 |
v[3] = min_t(u64, val, UINT_MAX); |
ada75b6e5 blk-throttle: add... |
1592 1593 |
else if (off == LIMIT_LOW && !strcmp(tok, "idle")) idle_time = val; |
ec80991d6 blk-throttle: add... |
1594 1595 |
else if (off == LIMIT_LOW && !strcmp(tok, "latency")) latency_time = val; |
2ee867dcf blkcg: implement ... |
1596 1597 1598 |
else goto out_finish; } |
cd5ab1b0f blk-throttle: add... |
1599 1600 1601 1602 |
tg->bps_conf[READ][index] = v[0]; tg->bps_conf[WRITE][index] = v[1]; tg->iops_conf[READ][index] = v[2]; tg->iops_conf[WRITE][index] = v[3]; |
2ee867dcf blkcg: implement ... |
1603 |
|
cd5ab1b0f blk-throttle: add... |
1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 |
if (index == LIMIT_MAX) { tg->bps[READ][index] = v[0]; tg->bps[WRITE][index] = v[1]; tg->iops[READ][index] = v[2]; tg->iops[WRITE][index] = v[3]; } tg->bps[READ][LIMIT_LOW] = min(tg->bps_conf[READ][LIMIT_LOW], tg->bps_conf[READ][LIMIT_MAX]); tg->bps[WRITE][LIMIT_LOW] = min(tg->bps_conf[WRITE][LIMIT_LOW], tg->bps_conf[WRITE][LIMIT_MAX]); tg->iops[READ][LIMIT_LOW] = min(tg->iops_conf[READ][LIMIT_LOW], tg->iops_conf[READ][LIMIT_MAX]); tg->iops[WRITE][LIMIT_LOW] = min(tg->iops_conf[WRITE][LIMIT_LOW], tg->iops_conf[WRITE][LIMIT_MAX]); |
b4f428ef2 blk-throttle: for... |
1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 |
tg->idletime_threshold_conf = idle_time; tg->latency_target_conf = latency_time; /* force user to configure all settings for low limit */ if (!(tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW] || tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) || tg->idletime_threshold_conf == DFL_IDLE_THRESHOLD || tg->latency_target_conf == DFL_LATENCY_TARGET) { tg->bps[READ][LIMIT_LOW] = 0; tg->bps[WRITE][LIMIT_LOW] = 0; tg->iops[READ][LIMIT_LOW] = 0; tg->iops[WRITE][LIMIT_LOW] = 0; tg->idletime_threshold = DFL_IDLE_THRESHOLD; tg->latency_target = DFL_LATENCY_TARGET; } else if (index == LIMIT_LOW) { |
5b81fc3cc blk-throttle: add... |
1633 |
tg->idletime_threshold = tg->idletime_threshold_conf; |
5b81fc3cc blk-throttle: add... |
1634 |
tg->latency_target = tg->latency_target_conf; |
cd5ab1b0f blk-throttle: add... |
1635 |
} |
b4f428ef2 blk-throttle: for... |
1636 1637 1638 1639 1640 1641 1642 |
blk_throtl_update_limit_valid(tg->td); if (tg->td->limit_valid[LIMIT_LOW]) { if (index == LIMIT_LOW) tg->td->limit_index = LIMIT_LOW; } else tg->td->limit_index = LIMIT_MAX; |
9bb67aeb9 blk-throttle: res... |
1643 1644 |
tg_conf_updated(tg, index == LIMIT_LOW && tg->td->limit_valid[LIMIT_LOW]); |
2ee867dcf blkcg: implement ... |
1645 1646 1647 1648 1649 1650 1651 |
ret = 0; out_finish: blkg_conf_finish(&ctx); return ret ?: nbytes; } static struct cftype throtl_files[] = { |
cd5ab1b0f blk-throttle: add... |
1652 1653 1654 1655 1656 1657 1658 1659 1660 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW { .name = "low", .flags = CFTYPE_NOT_ON_ROOT, .seq_show = tg_print_limit, .write = tg_set_limit, .private = LIMIT_LOW, }, #endif |
2ee867dcf blkcg: implement ... |
1661 1662 1663 |
{ .name = "max", .flags = CFTYPE_NOT_ON_ROOT, |
cd5ab1b0f blk-throttle: add... |
1664 1665 1666 |
.seq_show = tg_print_limit, .write = tg_set_limit, .private = LIMIT_MAX, |
2ee867dcf blkcg: implement ... |
1667 1668 1669 |
}, { } /* terminate */ }; |
da5277700 block: Move blk_t... |
1670 |
static void throtl_shutdown_wq(struct request_queue *q) |
e43473b7f blkio: Core imple... |
1671 1672 |
{ struct throtl_data *td = q->td; |
69df0ab03 blk-throttle: sep... |
1673 |
cancel_work_sync(&td->dispatch_work); |
e43473b7f blkio: Core imple... |
1674 |
} |
3c798398e blkcg: mass renam... |
1675 |
static struct blkcg_policy blkcg_policy_throtl = { |
2ee867dcf blkcg: implement ... |
1676 |
.dfl_cftypes = throtl_files, |
880f50e22 blkcg: mark exist... |
1677 |
.legacy_cftypes = throtl_legacy_files, |
f9fcc2d39 blkcg: collapse b... |
1678 |
|
001bea73e blkcg: replace bl... |
1679 |
.pd_alloc_fn = throtl_pd_alloc, |
f9fcc2d39 blkcg: collapse b... |
1680 |
.pd_init_fn = throtl_pd_init, |
693e751e7 blk-throttle: imp... |
1681 |
.pd_online_fn = throtl_pd_online, |
cd5ab1b0f blk-throttle: add... |
1682 |
.pd_offline_fn = throtl_pd_offline, |
001bea73e blkcg: replace bl... |
1683 |
.pd_free_fn = throtl_pd_free, |
e43473b7f blkio: Core imple... |
1684 |
}; |
3f0abd806 blk-throttle: add... |
1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 |
static unsigned long __tg_last_low_overflow_time(struct throtl_grp *tg) { unsigned long rtime = jiffies, wtime = jiffies; if (tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW]) rtime = tg->last_low_overflow_time[READ]; if (tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) wtime = tg->last_low_overflow_time[WRITE]; return min(rtime, wtime); } /* tg should not be an intermediate node */ static unsigned long tg_last_low_overflow_time(struct throtl_grp *tg) { struct throtl_service_queue *parent_sq; struct throtl_grp *parent = tg; unsigned long ret = __tg_last_low_overflow_time(tg); while (true) { parent_sq = parent->service_queue.parent_sq; parent = sq_to_tg(parent_sq); if (!parent) break; /* * The parent doesn't have low limit, it always reaches low * limit. Its overflow time is useless for children */ if (!parent->bps[READ][LIMIT_LOW] && !parent->iops[READ][LIMIT_LOW] && !parent->bps[WRITE][LIMIT_LOW] && !parent->iops[WRITE][LIMIT_LOW]) continue; if (time_after(__tg_last_low_overflow_time(parent), ret)) ret = __tg_last_low_overflow_time(parent); } return ret; } |
9e234eeaf blk-throttle: add... |
1723 1724 1725 1726 1727 |
static bool throtl_tg_is_idle(struct throtl_grp *tg) { /* * cgroup is idle if: * - single idle is too long, longer than a fixed value (in case user |
b4f428ef2 blk-throttle: for... |
1728 |
* configure a too big threshold) or 4 times of idletime threshold |
9e234eeaf blk-throttle: add... |
1729 |
* - average think time is more than threshold |
53696b8d2 blk-throttle: add... |
1730 |
* - IO latency is largely below threshold |
9e234eeaf blk-throttle: add... |
1731 |
*/ |
b4f428ef2 blk-throttle: for... |
1732 |
unsigned long time; |
4cff729f6 blk-throttle: out... |
1733 |
bool ret; |
9e234eeaf blk-throttle: add... |
1734 |
|
b4f428ef2 blk-throttle: for... |
1735 1736 1737 1738 1739 1740 |
time = min_t(unsigned long, MAX_IDLE_TIME, 4 * tg->idletime_threshold); ret = tg->latency_target == DFL_LATENCY_TARGET || tg->idletime_threshold == DFL_IDLE_THRESHOLD || (ktime_get_ns() >> 10) - tg->last_finish_time > time || tg->avg_idletime > tg->idletime_threshold || (tg->latency_target && tg->bio_cnt && |
53696b8d2 blk-throttle: add... |
1741 |
tg->bad_bio_cnt * 5 < tg->bio_cnt); |
4cff729f6 blk-throttle: out... |
1742 1743 1744 1745 1746 |
throtl_log(&tg->service_queue, "avg_idle=%ld, idle_threshold=%ld, bad_bio=%d, total_bio=%d, is_idle=%d, scale=%d", tg->avg_idletime, tg->idletime_threshold, tg->bad_bio_cnt, tg->bio_cnt, ret, tg->td->scale); return ret; |
9e234eeaf blk-throttle: add... |
1747 |
} |
c79892c55 blk-throttle: add... |
1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 |
static bool throtl_tg_can_upgrade(struct throtl_grp *tg) { struct throtl_service_queue *sq = &tg->service_queue; bool read_limit, write_limit; /* * if cgroup reaches low limit (if low limit is 0, the cgroup always * reaches), it's ok to upgrade to next limit */ read_limit = tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW]; write_limit = tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]; if (!read_limit && !write_limit) return true; if (read_limit && sq->nr_queued[READ] && (!write_limit || sq->nr_queued[WRITE])) return true; if (write_limit && sq->nr_queued[WRITE] && (!read_limit || sq->nr_queued[READ])) return true; |
aec242468 blk-throttle: det... |
1767 1768 |
if (time_after_eq(jiffies, |
fa6fb5aab blk-throttle: ign... |
1769 1770 |
tg_last_low_overflow_time(tg) + tg->td->throtl_slice) && throtl_tg_is_idle(tg)) |
aec242468 blk-throttle: det... |
1771 |
return true; |
c79892c55 blk-throttle: add... |
1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 |
return false; } static bool throtl_hierarchy_can_upgrade(struct throtl_grp *tg) { while (true) { if (throtl_tg_can_upgrade(tg)) return true; tg = sq_to_tg(tg->service_queue.parent_sq); if (!tg || !tg_to_blkg(tg)->parent) return false; } return false; } static bool throtl_can_upgrade(struct throtl_data *td, struct throtl_grp *this_tg) { struct cgroup_subsys_state *pos_css; struct blkcg_gq *blkg; if (td->limit_index != LIMIT_LOW) return false; |
297e3d854 blk-throttle: mak... |
1795 |
if (time_before(jiffies, td->low_downgrade_time + td->throtl_slice)) |
3f0abd806 blk-throttle: add... |
1796 |
return false; |
c79892c55 blk-throttle: add... |
1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 |
rcu_read_lock(); blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); if (tg == this_tg) continue; if (!list_empty(&tg_to_blkg(tg)->blkcg->css.children)) continue; if (!throtl_hierarchy_can_upgrade(tg)) { rcu_read_unlock(); return false; } } rcu_read_unlock(); return true; } |
fa6fb5aab blk-throttle: ign... |
1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 |
static void throtl_upgrade_check(struct throtl_grp *tg) { unsigned long now = jiffies; if (tg->td->limit_index != LIMIT_LOW) return; if (time_after(tg->last_check_time + tg->td->throtl_slice, now)) return; tg->last_check_time = now; if (!time_after_eq(now, __tg_last_low_overflow_time(tg) + tg->td->throtl_slice)) return; if (throtl_can_upgrade(tg->td, NULL)) throtl_upgrade_state(tg->td); } |
c79892c55 blk-throttle: add... |
1832 1833 1834 1835 |
static void throtl_upgrade_state(struct throtl_data *td) { struct cgroup_subsys_state *pos_css; struct blkcg_gq *blkg; |
4cff729f6 blk-throttle: out... |
1836 |
throtl_log(&td->service_queue, "upgrade to max"); |
c79892c55 blk-throttle: add... |
1837 |
td->limit_index = LIMIT_MAX; |
3f0abd806 blk-throttle: add... |
1838 |
td->low_upgrade_time = jiffies; |
7394e31fa blk-throttle: mak... |
1839 |
td->scale = 0; |
c79892c55 blk-throttle: add... |
1840 1841 1842 1843 1844 1845 1846 |
rcu_read_lock(); blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); struct throtl_service_queue *sq = &tg->service_queue; tg->disptime = jiffies - 1; throtl_select_dispatch(sq); |
4f02fb761 blk-throttle: fix... |
1847 |
throtl_schedule_next_dispatch(sq, true); |
c79892c55 blk-throttle: add... |
1848 1849 1850 |
} rcu_read_unlock(); throtl_select_dispatch(&td->service_queue); |
4f02fb761 blk-throttle: fix... |
1851 |
throtl_schedule_next_dispatch(&td->service_queue, true); |
c79892c55 blk-throttle: add... |
1852 1853 |
queue_work(kthrotld_workqueue, &td->dispatch_work); } |
4247d9c8b blk-throttle: Rem... |
1854 |
static void throtl_downgrade_state(struct throtl_data *td) |
3f0abd806 blk-throttle: add... |
1855 |
{ |
7394e31fa blk-throttle: mak... |
1856 |
td->scale /= 2; |
4cff729f6 blk-throttle: out... |
1857 |
throtl_log(&td->service_queue, "downgrade, scale %d", td->scale); |
7394e31fa blk-throttle: mak... |
1858 1859 1860 1861 |
if (td->scale) { td->low_upgrade_time = jiffies - td->scale * td->throtl_slice; return; } |
4247d9c8b blk-throttle: Rem... |
1862 |
td->limit_index = LIMIT_LOW; |
3f0abd806 blk-throttle: add... |
1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 |
td->low_downgrade_time = jiffies; } static bool throtl_tg_can_downgrade(struct throtl_grp *tg) { struct throtl_data *td = tg->td; unsigned long now = jiffies; /* * If cgroup is below low limit, consider downgrade and throttle other * cgroups */ |
297e3d854 blk-throttle: mak... |
1875 1876 |
if (time_after_eq(now, td->low_upgrade_time + td->throtl_slice) && time_after_eq(now, tg_last_low_overflow_time(tg) + |
fa6fb5aab blk-throttle: ign... |
1877 1878 1879 |
td->throtl_slice) && (!throtl_tg_is_idle(tg) || !list_empty(&tg_to_blkg(tg)->blkcg->css.children))) |
3f0abd806 blk-throttle: add... |
1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 |
return true; return false; } static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg) { while (true) { if (!throtl_tg_can_downgrade(tg)) return false; tg = sq_to_tg(tg->service_queue.parent_sq); if (!tg || !tg_to_blkg(tg)->parent) break; } return true; } static void throtl_downgrade_check(struct throtl_grp *tg) { uint64_t bps; unsigned int iops; unsigned long elapsed_time; unsigned long now = jiffies; if (tg->td->limit_index != LIMIT_MAX || !tg->td->limit_valid[LIMIT_LOW]) return; if (!list_empty(&tg_to_blkg(tg)->blkcg->css.children)) return; |
297e3d854 blk-throttle: mak... |
1908 |
if (time_after(tg->last_check_time + tg->td->throtl_slice, now)) |
3f0abd806 blk-throttle: add... |
1909 1910 1911 1912 |
return; elapsed_time = now - tg->last_check_time; tg->last_check_time = now; |
297e3d854 blk-throttle: mak... |
1913 1914 |
if (time_before(now, tg_last_low_overflow_time(tg) + tg->td->throtl_slice)) |
3f0abd806 blk-throttle: add... |
1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 |
return; if (tg->bps[READ][LIMIT_LOW]) { bps = tg->last_bytes_disp[READ] * HZ; do_div(bps, elapsed_time); if (bps >= tg->bps[READ][LIMIT_LOW]) tg->last_low_overflow_time[READ] = now; } if (tg->bps[WRITE][LIMIT_LOW]) { bps = tg->last_bytes_disp[WRITE] * HZ; do_div(bps, elapsed_time); if (bps >= tg->bps[WRITE][LIMIT_LOW]) tg->last_low_overflow_time[WRITE] = now; } if (tg->iops[READ][LIMIT_LOW]) { iops = tg->last_io_disp[READ] * HZ / elapsed_time; if (iops >= tg->iops[READ][LIMIT_LOW]) tg->last_low_overflow_time[READ] = now; } if (tg->iops[WRITE][LIMIT_LOW]) { iops = tg->last_io_disp[WRITE] * HZ / elapsed_time; if (iops >= tg->iops[WRITE][LIMIT_LOW]) tg->last_low_overflow_time[WRITE] = now; } /* * If cgroup is below low limit, consider downgrade and throttle other * cgroups */ if (throtl_hierarchy_can_downgrade(tg)) |
4247d9c8b blk-throttle: Rem... |
1948 |
throtl_downgrade_state(tg->td); |
3f0abd806 blk-throttle: add... |
1949 1950 1951 1952 1953 1954 |
tg->last_bytes_disp[READ] = 0; tg->last_bytes_disp[WRITE] = 0; tg->last_io_disp[READ] = 0; tg->last_io_disp[WRITE] = 0; } |
9e234eeaf blk-throttle: add... |
1955 1956 |
static void blk_throtl_update_idletime(struct throtl_grp *tg) { |
7901601ae blk-throttle: Avo... |
1957 |
unsigned long now; |
9e234eeaf blk-throttle: add... |
1958 |
unsigned long last_finish_time = tg->last_finish_time; |
7901601ae blk-throttle: Avo... |
1959 1960 1961 1962 1963 |
if (last_finish_time == 0) return; now = ktime_get_ns() >> 10; if (now <= last_finish_time || |
9e234eeaf blk-throttle: add... |
1964 1965 1966 1967 1968 1969 |
last_finish_time == tg->checked_last_finish_time) return; tg->avg_idletime = (tg->avg_idletime * 7 + now - last_finish_time) >> 3; tg->checked_last_finish_time = last_finish_time; } |
b9147dd1b blk-throttle: add... |
1970 1971 1972 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW static void throtl_update_latency_buckets(struct throtl_data *td) { |
b889bf66d blk-throttle: tra... |
1973 1974 1975 1976 |
struct avg_latency_bucket avg_latency[2][LATENCY_BUCKET_SIZE]; int i, cpu, rw; unsigned long last_latency[2] = { 0 }; unsigned long latency[2]; |
b9147dd1b blk-throttle: add... |
1977 |
|
b185efa78 blk-throttle: Avo... |
1978 |
if (!blk_queue_nonrot(td->queue) || !td->limit_valid[LIMIT_LOW]) |
b9147dd1b blk-throttle: add... |
1979 1980 1981 1982 1983 1984 |
return; if (time_before(jiffies, td->last_calculate_time + HZ)) return; td->last_calculate_time = jiffies; memset(avg_latency, 0, sizeof(avg_latency)); |
b889bf66d blk-throttle: tra... |
1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 |
for (rw = READ; rw <= WRITE; rw++) { for (i = 0; i < LATENCY_BUCKET_SIZE; i++) { struct latency_bucket *tmp = &td->tmp_buckets[rw][i]; for_each_possible_cpu(cpu) { struct latency_bucket *bucket; /* this isn't race free, but ok in practice */ bucket = per_cpu_ptr(td->latency_buckets[rw], cpu); tmp->total_latency += bucket[i].total_latency; tmp->samples += bucket[i].samples; bucket[i].total_latency = 0; bucket[i].samples = 0; } |
b9147dd1b blk-throttle: add... |
2000 |
|
b889bf66d blk-throttle: tra... |
2001 2002 |
if (tmp->samples >= 32) { int samples = tmp->samples; |
b9147dd1b blk-throttle: add... |
2003 |
|
b889bf66d blk-throttle: tra... |
2004 |
latency[rw] = tmp->total_latency; |
b9147dd1b blk-throttle: add... |
2005 |
|
b889bf66d blk-throttle: tra... |
2006 2007 2008 2009 2010 2011 2012 |
tmp->total_latency = 0; tmp->samples = 0; latency[rw] /= samples; if (latency[rw] == 0) continue; avg_latency[rw][i].latency = latency[rw]; } |
b9147dd1b blk-throttle: add... |
2013 2014 |
} } |
b889bf66d blk-throttle: tra... |
2015 2016 2017 2018 2019 2020 2021 2022 |
for (rw = READ; rw <= WRITE; rw++) { for (i = 0; i < LATENCY_BUCKET_SIZE; i++) { if (!avg_latency[rw][i].latency) { if (td->avg_buckets[rw][i].latency < last_latency[rw]) td->avg_buckets[rw][i].latency = last_latency[rw]; continue; } |
b9147dd1b blk-throttle: add... |
2023 |
|
b889bf66d blk-throttle: tra... |
2024 2025 2026 2027 2028 |
if (!td->avg_buckets[rw][i].valid) latency[rw] = avg_latency[rw][i].latency; else latency[rw] = (td->avg_buckets[rw][i].latency * 7 + avg_latency[rw][i].latency) >> 3; |
b9147dd1b blk-throttle: add... |
2029 |
|
b889bf66d blk-throttle: tra... |
2030 2031 2032 2033 2034 |
td->avg_buckets[rw][i].latency = max(latency[rw], last_latency[rw]); td->avg_buckets[rw][i].valid = true; last_latency[rw] = td->avg_buckets[rw][i].latency; } |
b9147dd1b blk-throttle: add... |
2035 |
} |
4cff729f6 blk-throttle: out... |
2036 2037 2038 |
for (i = 0; i < LATENCY_BUCKET_SIZE; i++) throtl_log(&td->service_queue, |
b889bf66d blk-throttle: tra... |
2039 2040 2041 2042 2043 2044 |
"Latency bucket %d: read latency=%ld, read valid=%d, " "write latency=%ld, write valid=%d", i, td->avg_buckets[READ][i].latency, td->avg_buckets[READ][i].valid, td->avg_buckets[WRITE][i].latency, td->avg_buckets[WRITE][i].valid); |
b9147dd1b blk-throttle: add... |
2045 2046 2047 2048 2049 2050 |
} #else static inline void throtl_update_latency_buckets(struct throtl_data *td) { } #endif |
db18a53e5 blk-cgroup: remov... |
2051 |
bool blk_throtl_bio(struct bio *bio) |
e43473b7f blkio: Core imple... |
2052 |
{ |
db18a53e5 blk-cgroup: remov... |
2053 2054 |
struct request_queue *q = bio->bi_disk->queue; struct blkcg_gq *blkg = bio->bi_blkg; |
c5cc2070b blk-throttle: add... |
2055 |
struct throtl_qnode *qn = NULL; |
a2e83ef9c blk-cgroup: remov... |
2056 |
struct throtl_grp *tg = blkg_to_tg(blkg); |
73f0d49a9 blk-throttle: mov... |
2057 |
struct throtl_service_queue *sq; |
0e9f4164b blk-throttle: gen... |
2058 |
bool rw = bio_data_dir(bio); |
bc16a4f93 block: reorganize... |
2059 |
bool throttled = false; |
b9147dd1b blk-throttle: add... |
2060 |
struct throtl_data *td = tg->td; |
e43473b7f blkio: Core imple... |
2061 |
|
93b806380 blk-cgroup: move ... |
2062 |
rcu_read_lock(); |
ae1188963 blkcg: consolidat... |
2063 |
|
2a0f61e6e blk-throttle: set... |
2064 |
/* see throtl_charge_bio() */ |
7ca464383 blk-throtl: stop ... |
2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 |
if (bio_flagged(bio, BIO_THROTTLED)) goto out; if (!cgroup_subsys_on_dfl(io_cgrp_subsys)) { blkg_rwstat_add(&tg->stat_bytes, bio->bi_opf, bio->bi_iter.bi_size); blkg_rwstat_add(&tg->stat_ios, bio->bi_opf, 1); } if (!tg->has_rules[rw]) |
bc16a4f93 block: reorganize... |
2075 |
goto out; |
e43473b7f blkio: Core imple... |
2076 |
|
0d945c1f9 block: remove the... |
2077 |
spin_lock_irq(&q->queue_lock); |
c9589f03e blk-throttle: imp... |
2078 |
|
b9147dd1b blk-throttle: add... |
2079 |
throtl_update_latency_buckets(td); |
9e234eeaf blk-throttle: add... |
2080 |
blk_throtl_update_idletime(tg); |
73f0d49a9 blk-throttle: mov... |
2081 |
sq = &tg->service_queue; |
c79892c55 blk-throttle: add... |
2082 |
again: |
9e660acff blk-throttle: mak... |
2083 |
while (true) { |
3f0abd806 blk-throttle: add... |
2084 2085 2086 |
if (tg->last_low_overflow_time[rw] == 0) tg->last_low_overflow_time[rw] = jiffies; throtl_downgrade_check(tg); |
fa6fb5aab blk-throttle: ign... |
2087 |
throtl_upgrade_check(tg); |
9e660acff blk-throttle: mak... |
2088 2089 2090 |
/* throtl is FIFO - if bios are already queued, should queue */ if (sq->nr_queued[rw]) break; |
de701c74a blk-throttle: Som... |
2091 |
|
9e660acff blk-throttle: mak... |
2092 |
/* if above limits, break to queue */ |
c79892c55 blk-throttle: add... |
2093 |
if (!tg_may_dispatch(tg, bio, NULL)) { |
3f0abd806 blk-throttle: add... |
2094 |
tg->last_low_overflow_time[rw] = jiffies; |
b9147dd1b blk-throttle: add... |
2095 2096 |
if (throtl_can_upgrade(td, tg)) { throtl_upgrade_state(td); |
c79892c55 blk-throttle: add... |
2097 2098 |
goto again; } |
9e660acff blk-throttle: mak... |
2099 |
break; |
c79892c55 blk-throttle: add... |
2100 |
} |
9e660acff blk-throttle: mak... |
2101 2102 |
/* within limits, let's charge and dispatch directly */ |
e43473b7f blkio: Core imple... |
2103 |
throtl_charge_bio(tg, bio); |
04521db04 blk-throttle: Res... |
2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 |
/* * We need to trim slice even when bios are not being queued * otherwise it might happen that a bio is not queued for * a long time and slice keeps on extending and trim is not * called for a long time. Now if limits are reduced suddenly * we take into account all the IO dispatched so far at new * low rate and * newly queued IO gets a really long dispatch * time. * * So keep on trimming slice even if bio is not queued. */ |
0f3457f60 blk-throttle: add... |
2116 |
throtl_trim_slice(tg, rw); |
9e660acff blk-throttle: mak... |
2117 2118 2119 |
/* * @bio passed through this layer without being throttled. |
b53b072c4 blk-throttle: Fix... |
2120 |
* Climb up the ladder. If we're already at the top, it |
9e660acff blk-throttle: mak... |
2121 2122 |
* can be executed directly. */ |
c5cc2070b blk-throttle: add... |
2123 |
qn = &tg->qnode_on_parent[rw]; |
9e660acff blk-throttle: mak... |
2124 2125 2126 2127 |
sq = sq->parent_sq; tg = sq_to_tg(sq); if (!tg) goto out_unlock; |
e43473b7f blkio: Core imple... |
2128 |
} |
9e660acff blk-throttle: mak... |
2129 |
/* out-of-limit, queue to @tg */ |
fda6f272c blk-throttle: imp... |
2130 2131 |
throtl_log(sq, "[%c] bio. bdisp=%llu sz=%u bps=%llu iodisp=%u iops=%u queued=%d/%d", rw == READ ? 'R' : 'W', |
9f626e372 blk-throttle: pre... |
2132 2133 2134 |
tg->bytes_disp[rw], bio->bi_iter.bi_size, tg_bps_limit(tg, rw), tg->io_disp[rw], tg_iops_limit(tg, rw), |
fda6f272c blk-throttle: imp... |
2135 |
sq->nr_queued[READ], sq->nr_queued[WRITE]); |
e43473b7f blkio: Core imple... |
2136 |
|
3f0abd806 blk-throttle: add... |
2137 |
tg->last_low_overflow_time[rw] = jiffies; |
b9147dd1b blk-throttle: add... |
2138 |
td->nr_queued[rw]++; |
c5cc2070b blk-throttle: add... |
2139 |
throtl_add_bio_tg(bio, qn, tg); |
bc16a4f93 block: reorganize... |
2140 |
throttled = true; |
e43473b7f blkio: Core imple... |
2141 |
|
7f52f98c2 blk-throttle: imp... |
2142 2143 2144 2145 2146 2147 |
/* * Update @tg's dispatch time and force schedule dispatch if @tg * was empty before @bio. The forced scheduling isn't likely to * cause undue delay as @bio is likely to be dispatched directly if * its @tg's disptime is not in the future. */ |
0e9f4164b blk-throttle: gen... |
2148 |
if (tg->flags & THROTL_TG_WAS_EMPTY) { |
77216b048 blk-throttle: add... |
2149 |
tg_update_disptime(tg); |
7f52f98c2 blk-throttle: imp... |
2150 |
throtl_schedule_next_dispatch(tg->service_queue.parent_sq, true); |
e43473b7f blkio: Core imple... |
2151 |
} |
bc16a4f93 block: reorganize... |
2152 |
out_unlock: |
0d945c1f9 block: remove the... |
2153 |
spin_unlock_irq(&q->queue_lock); |
bc16a4f93 block: reorganize... |
2154 |
out: |
111be8839 block-throttle: a... |
2155 |
bio_set_flag(bio, BIO_THROTTLED); |
b9147dd1b blk-throttle: add... |
2156 2157 2158 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW if (throttled || !td->track_bio_latency) |
5238dcf41 block: replace bi... |
2159 |
bio->bi_issue.value |= BIO_ISSUE_THROTL_SKIP_LATENCY; |
b9147dd1b blk-throttle: add... |
2160 |
#endif |
93b806380 blk-cgroup: move ... |
2161 |
rcu_read_unlock(); |
bc16a4f93 block: reorganize... |
2162 |
return throttled; |
e43473b7f blkio: Core imple... |
2163 |
} |
9e234eeaf blk-throttle: add... |
2164 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW |
b9147dd1b blk-throttle: add... |
2165 2166 2167 2168 2169 |
static void throtl_track_latency(struct throtl_data *td, sector_t size, int op, unsigned long time) { struct latency_bucket *latency; int index; |
b889bf66d blk-throttle: tra... |
2170 2171 |
if (!td || td->limit_index != LIMIT_LOW || !(op == REQ_OP_READ || op == REQ_OP_WRITE) || |
b9147dd1b blk-throttle: add... |
2172 2173 2174 2175 |
!blk_queue_nonrot(td->queue)) return; index = request_bucket_index(size); |
b889bf66d blk-throttle: tra... |
2176 |
latency = get_cpu_ptr(td->latency_buckets[op]); |
b9147dd1b blk-throttle: add... |
2177 2178 |
latency[index].total_latency += time; latency[index].samples++; |
b889bf66d blk-throttle: tra... |
2179 |
put_cpu_ptr(td->latency_buckets[op]); |
b9147dd1b blk-throttle: add... |
2180 2181 2182 2183 2184 2185 |
} void blk_throtl_stat_add(struct request *rq, u64 time_ns) { struct request_queue *q = rq->q; struct throtl_data *td = q->td; |
3d2443069 block: make rq se... |
2186 2187 |
throtl_track_latency(td, blk_rq_stats_sectors(rq), req_op(rq), time_ns >> 10); |
b9147dd1b blk-throttle: add... |
2188 |
} |
9e234eeaf blk-throttle: add... |
2189 2190 |
void blk_throtl_bio_endio(struct bio *bio) { |
08e18eab0 block: add bi_blk... |
2191 |
struct blkcg_gq *blkg; |
9e234eeaf blk-throttle: add... |
2192 |
struct throtl_grp *tg; |
b9147dd1b blk-throttle: add... |
2193 2194 2195 2196 |
u64 finish_time_ns; unsigned long finish_time; unsigned long start_time; unsigned long lat; |
b889bf66d blk-throttle: tra... |
2197 |
int rw = bio_data_dir(bio); |
9e234eeaf blk-throttle: add... |
2198 |
|
08e18eab0 block: add bi_blk... |
2199 2200 |
blkg = bio->bi_blkg; if (!blkg) |
9e234eeaf blk-throttle: add... |
2201 |
return; |
08e18eab0 block: add bi_blk... |
2202 |
tg = blkg_to_tg(blkg); |
b185efa78 blk-throttle: Avo... |
2203 2204 |
if (!tg->td->limit_valid[LIMIT_LOW]) return; |
9e234eeaf blk-throttle: add... |
2205 |
|
b9147dd1b blk-throttle: add... |
2206 2207 |
finish_time_ns = ktime_get_ns(); tg->last_finish_time = finish_time_ns >> 10; |
5238dcf41 block: replace bi... |
2208 2209 |
start_time = bio_issue_time(&bio->bi_issue) >> 10; finish_time = __bio_issue_time(finish_time_ns) >> 10; |
08e18eab0 block: add bi_blk... |
2210 |
if (!start_time || finish_time <= start_time) |
53696b8d2 blk-throttle: add... |
2211 2212 2213 |
return; lat = finish_time - start_time; |
b9147dd1b blk-throttle: add... |
2214 |
/* this is only for bio based driver */ |
5238dcf41 block: replace bi... |
2215 2216 2217 |
if (!(bio->bi_issue.value & BIO_ISSUE_THROTL_SKIP_LATENCY)) throtl_track_latency(tg->td, bio_issue_size(&bio->bi_issue), bio_op(bio), lat); |
53696b8d2 blk-throttle: add... |
2218 |
|
6679a90c4 blk-throttle: set... |
2219 |
if (tg->latency_target && lat >= tg->td->filtered_latency) { |
53696b8d2 blk-throttle: add... |
2220 2221 |
int bucket; unsigned int threshold; |
5238dcf41 block: replace bi... |
2222 |
bucket = request_bucket_index(bio_issue_size(&bio->bi_issue)); |
b889bf66d blk-throttle: tra... |
2223 |
threshold = tg->td->avg_buckets[rw][bucket].latency + |
53696b8d2 blk-throttle: add... |
2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 |
tg->latency_target; if (lat > threshold) tg->bad_bio_cnt++; /* * Not race free, could get wrong count, which means cgroups * will be throttled */ tg->bio_cnt++; } if (time_after(jiffies, tg->bio_cnt_reset_time) || tg->bio_cnt > 1024) { tg->bio_cnt_reset_time = tg->td->throtl_slice + jiffies; tg->bio_cnt /= 2; tg->bad_bio_cnt /= 2; |
b9147dd1b blk-throttle: add... |
2238 |
} |
9e234eeaf blk-throttle: add... |
2239 2240 |
} #endif |
e43473b7f blkio: Core imple... |
2241 2242 2243 |
int blk_throtl_init(struct request_queue *q) { struct throtl_data *td; |
a2b1693ba blkcg: implement ... |
2244 |
int ret; |
e43473b7f blkio: Core imple... |
2245 2246 2247 2248 |
td = kzalloc_node(sizeof(*td), GFP_KERNEL, q->node); if (!td) return -ENOMEM; |
b889bf66d blk-throttle: tra... |
2249 |
td->latency_buckets[READ] = __alloc_percpu(sizeof(struct latency_bucket) * |
b9147dd1b blk-throttle: add... |
2250 |
LATENCY_BUCKET_SIZE, __alignof__(u64)); |
b889bf66d blk-throttle: tra... |
2251 2252 2253 2254 2255 |
if (!td->latency_buckets[READ]) { kfree(td); return -ENOMEM; } td->latency_buckets[WRITE] = __alloc_percpu(sizeof(struct latency_bucket) * |
b9147dd1b blk-throttle: add... |
2256 |
LATENCY_BUCKET_SIZE, __alignof__(u64)); |
b889bf66d blk-throttle: tra... |
2257 2258 |
if (!td->latency_buckets[WRITE]) { free_percpu(td->latency_buckets[READ]); |
b9147dd1b blk-throttle: add... |
2259 2260 2261 |
kfree(td); return -ENOMEM; } |
e43473b7f blkio: Core imple... |
2262 |
|
69df0ab03 blk-throttle: sep... |
2263 |
INIT_WORK(&td->dispatch_work, blk_throtl_dispatch_work_fn); |
b2ce2643c blk-throttle: cle... |
2264 |
throtl_service_queue_init(&td->service_queue); |
e43473b7f blkio: Core imple... |
2265 |
|
cd1604fab blkcg: factor out... |
2266 |
q->td = td; |
29b125892 blk-throttle: Dyn... |
2267 |
td->queue = q; |
02977e4af blkio: Add root g... |
2268 |
|
9f626e372 blk-throttle: pre... |
2269 |
td->limit_valid[LIMIT_MAX] = true; |
cd5ab1b0f blk-throttle: add... |
2270 |
td->limit_index = LIMIT_MAX; |
3f0abd806 blk-throttle: add... |
2271 2272 |
td->low_upgrade_time = jiffies; td->low_downgrade_time = jiffies; |
9e234eeaf blk-throttle: add... |
2273 |
|
a2b1693ba blkcg: implement ... |
2274 |
/* activate policy */ |
3c798398e blkcg: mass renam... |
2275 |
ret = blkcg_activate_policy(q, &blkcg_policy_throtl); |
b9147dd1b blk-throttle: add... |
2276 |
if (ret) { |
b889bf66d blk-throttle: tra... |
2277 2278 |
free_percpu(td->latency_buckets[READ]); free_percpu(td->latency_buckets[WRITE]); |
f51b802c1 blkcg: use the us... |
2279 |
kfree(td); |
b9147dd1b blk-throttle: add... |
2280 |
} |
a2b1693ba blkcg: implement ... |
2281 |
return ret; |
e43473b7f blkio: Core imple... |
2282 2283 2284 2285 |
} void blk_throtl_exit(struct request_queue *q) { |
c875f4d02 blkcg: drop unnec... |
2286 |
BUG_ON(!q->td); |
da5277700 block: Move blk_t... |
2287 |
throtl_shutdown_wq(q); |
3c798398e blkcg: mass renam... |
2288 |
blkcg_deactivate_policy(q, &blkcg_policy_throtl); |
b889bf66d blk-throttle: tra... |
2289 2290 |
free_percpu(q->td->latency_buckets[READ]); free_percpu(q->td->latency_buckets[WRITE]); |
c9a929dde block: fix reques... |
2291 |
kfree(q->td); |
e43473b7f blkio: Core imple... |
2292 |
} |
d61fcfa4b blk-throttle: cho... |
2293 2294 2295 |
void blk_throtl_register_queue(struct request_queue *q) { struct throtl_data *td; |
6679a90c4 blk-throttle: set... |
2296 |
int i; |
d61fcfa4b blk-throttle: cho... |
2297 2298 2299 |
td = q->td; BUG_ON(!td); |
6679a90c4 blk-throttle: set... |
2300 |
if (blk_queue_nonrot(q)) { |
d61fcfa4b blk-throttle: cho... |
2301 |
td->throtl_slice = DFL_THROTL_SLICE_SSD; |
6679a90c4 blk-throttle: set... |
2302 2303 |
td->filtered_latency = LATENCY_FILTERED_SSD; } else { |
d61fcfa4b blk-throttle: cho... |
2304 |
td->throtl_slice = DFL_THROTL_SLICE_HD; |
6679a90c4 blk-throttle: set... |
2305 |
td->filtered_latency = LATENCY_FILTERED_HD; |
b889bf66d blk-throttle: tra... |
2306 2307 2308 2309 |
for (i = 0; i < LATENCY_BUCKET_SIZE; i++) { td->avg_buckets[READ][i].latency = DFL_HD_BASELINE_LATENCY; td->avg_buckets[WRITE][i].latency = DFL_HD_BASELINE_LATENCY; } |
6679a90c4 blk-throttle: set... |
2310 |
} |
d61fcfa4b blk-throttle: cho... |
2311 2312 2313 2314 |
#ifndef CONFIG_BLK_DEV_THROTTLING_LOW /* if no low limit, use previous default */ td->throtl_slice = DFL_THROTL_SLICE_HD; #endif |
9e234eeaf blk-throttle: add... |
2315 |
|
344e9ffcb block: add queue_... |
2316 |
td->track_bio_latency = !queue_is_mq(q); |
b9147dd1b blk-throttle: add... |
2317 2318 |
if (!td->track_bio_latency) blk_stat_enable_accounting(q); |
d61fcfa4b blk-throttle: cho... |
2319 |
} |
297e3d854 blk-throttle: mak... |
2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page) { if (!q->td) return -EINVAL; return sprintf(page, "%u ", jiffies_to_msecs(q->td->throtl_slice)); } ssize_t blk_throtl_sample_time_store(struct request_queue *q, const char *page, size_t count) { unsigned long v; unsigned long t; if (!q->td) return -EINVAL; if (kstrtoul(page, 10, &v)) return -EINVAL; t = msecs_to_jiffies(v); if (t == 0 || t > MAX_THROTL_SLICE) return -EINVAL; q->td->throtl_slice = t; return count; } #endif |
e43473b7f blkio: Core imple... |
2346 2347 |
static int __init throtl_init(void) { |
450adcbe5 blk-throttle: Do ... |
2348 2349 2350 2351 |
kthrotld_workqueue = alloc_workqueue("kthrotld", WQ_MEM_RECLAIM, 0); if (!kthrotld_workqueue) panic("Failed to create kthrotld "); |
3c798398e blkcg: mass renam... |
2352 |
return blkcg_policy_register(&blkcg_policy_throtl); |
e43473b7f blkio: Core imple... |
2353 2354 2355 |
} module_init(throtl_init); |