Jens Axboe | 75bb462 | 2014-05-28 10:15:41 -0600 | [diff] [blame] | 1 | /* |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 2 | * Tag allocation using scalable bitmaps. Uses active queue tracking to support |
| 3 | * fairer distribution of tags between multiple submitters when a shared tag map |
| 4 | * is used. |
Jens Axboe | 75bb462 | 2014-05-28 10:15:41 -0600 | [diff] [blame] | 5 | * |
| 6 | * Copyright (C) 2013-2014 Jens Axboe |
| 7 | */ |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 8 | #include <linux/kernel.h> |
| 9 | #include <linux/module.h> |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 10 | |
| 11 | #include <linux/blk-mq.h> |
| 12 | #include "blk.h" |
| 13 | #include "blk-mq.h" |
| 14 | #include "blk-mq-tag.h" |
| 15 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 16 | bool blk_mq_has_free_tags(struct blk_mq_tags *tags) |
| 17 | { |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 18 | if (!tags) |
| 19 | return true; |
| 20 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 21 | return sbitmap_any_bit_clear(&tags->bitmap_tags.sb); |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 22 | } |
| 23 | |
| 24 | /* |
| 25 | * If a previously inactive queue goes active, bump the active user count. |
| 26 | */ |
| 27 | bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) |
| 28 | { |
| 29 | if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state) && |
| 30 | !test_and_set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) |
| 31 | atomic_inc(&hctx->tags->active_queues); |
| 32 | |
| 33 | return true; |
| 34 | } |
| 35 | |
| 36 | /* |
Jens Axboe | aed3ea9 | 2014-12-22 14:04:42 -0700 | [diff] [blame] | 37 | * Wakeup all potentially sleeping on tags |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 38 | */ |
Jens Axboe | aed3ea9 | 2014-12-22 14:04:42 -0700 | [diff] [blame] | 39 | void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool include_reserve) |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 40 | { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 41 | sbitmap_queue_wake_all(&tags->bitmap_tags); |
| 42 | if (include_reserve) |
| 43 | sbitmap_queue_wake_all(&tags->breserved_tags); |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 44 | } |
| 45 | |
| 46 | /* |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 47 | * If a previously busy queue goes inactive, potential waiters could now |
| 48 | * be allowed to queue. Wake them up and check. |
| 49 | */ |
| 50 | void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) |
| 51 | { |
| 52 | struct blk_mq_tags *tags = hctx->tags; |
| 53 | |
| 54 | if (!test_and_clear_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) |
| 55 | return; |
| 56 | |
| 57 | atomic_dec(&tags->active_queues); |
| 58 | |
Jens Axboe | aed3ea9 | 2014-12-22 14:04:42 -0700 | [diff] [blame] | 59 | blk_mq_tag_wakeup_all(tags, false); |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 60 | } |
| 61 | |
| 62 | /* |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 63 | * For shared tag users, we track the number of currently active users |
| 64 | * and attempt to provide a fair share of the tag depth for each of them. |
| 65 | */ |
| 66 | static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 67 | struct sbitmap_queue *bt) |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 68 | { |
| 69 | unsigned int depth, users; |
| 70 | |
| 71 | if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_SHARED)) |
| 72 | return true; |
| 73 | if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) |
| 74 | return true; |
| 75 | |
| 76 | /* |
| 77 | * Don't try dividing an ant |
| 78 | */ |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 79 | if (bt->sb.depth == 1) |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 80 | return true; |
| 81 | |
| 82 | users = atomic_read(&hctx->tags->active_queues); |
| 83 | if (!users) |
| 84 | return true; |
| 85 | |
| 86 | /* |
| 87 | * Allow at least some tags |
| 88 | */ |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 89 | depth = max((bt->sb.depth + users - 1) / users, 4U); |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 90 | return atomic_read(&hctx->nr_active) < depth; |
| 91 | } |
| 92 | |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 93 | static int __bt_get(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt) |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 94 | { |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 95 | if (!hctx_may_queue(hctx, bt)) |
| 96 | return -1; |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 97 | return __sbitmap_queue_get(bt); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 98 | } |
| 99 | |
Omar Sandoval | 40aabb6 | 2016-09-17 01:28:23 -0700 | [diff] [blame] | 100 | static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt, |
| 101 | struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags) |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 102 | { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 103 | struct sbq_wait_state *ws; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 104 | DEFINE_WAIT(wait); |
| 105 | int tag; |
| 106 | |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 107 | tag = __bt_get(hctx, bt); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 108 | if (tag != -1) |
| 109 | return tag; |
| 110 | |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 111 | if (data->flags & BLK_MQ_REQ_NOWAIT) |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 112 | return -1; |
| 113 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 114 | ws = bt_wait_ptr(bt, hctx); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 115 | do { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 116 | prepare_to_wait(&ws->wait, &wait, TASK_UNINTERRUPTIBLE); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 117 | |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 118 | tag = __bt_get(hctx, bt); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 119 | if (tag != -1) |
| 120 | break; |
| 121 | |
Bart Van Assche | b322320 | 2014-12-08 08:46:34 -0700 | [diff] [blame] | 122 | /* |
| 123 | * We're out of tags on this hardware queue, kick any |
| 124 | * pending IO submits before going to sleep waiting for |
Sam Bradshaw | bc188d8 | 2015-03-18 17:06:18 -0600 | [diff] [blame] | 125 | * some to complete. Note that hctx can be NULL here for |
| 126 | * reserved tag allocation. |
Bart Van Assche | b322320 | 2014-12-08 08:46:34 -0700 | [diff] [blame] | 127 | */ |
Sam Bradshaw | bc188d8 | 2015-03-18 17:06:18 -0600 | [diff] [blame] | 128 | if (hctx) |
| 129 | blk_mq_run_hw_queue(hctx, false); |
Bart Van Assche | b322320 | 2014-12-08 08:46:34 -0700 | [diff] [blame] | 130 | |
Jens Axboe | 080ff35 | 2014-12-08 08:49:06 -0700 | [diff] [blame] | 131 | /* |
| 132 | * Retry tag allocation after running the hardware queue, |
| 133 | * as running the queue may also have found completions. |
| 134 | */ |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 135 | tag = __bt_get(hctx, bt); |
Jens Axboe | 080ff35 | 2014-12-08 08:49:06 -0700 | [diff] [blame] | 136 | if (tag != -1) |
| 137 | break; |
| 138 | |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 139 | blk_mq_put_ctx(data->ctx); |
| 140 | |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 141 | io_schedule(); |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 142 | |
| 143 | data->ctx = blk_mq_get_ctx(data->q); |
Christoph Hellwig | 7d7e0f9 | 2016-09-14 16:18:54 +0200 | [diff] [blame] | 144 | data->hctx = blk_mq_map_queue(data->q, data->ctx->cpu); |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 145 | if (data->flags & BLK_MQ_REQ_RESERVED) { |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 146 | bt = &data->hctx->tags->breserved_tags; |
| 147 | } else { |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 148 | hctx = data->hctx; |
| 149 | bt = &hctx->tags->bitmap_tags; |
| 150 | } |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 151 | finish_wait(&ws->wait, &wait); |
| 152 | ws = bt_wait_ptr(bt, hctx); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 153 | } while (1); |
| 154 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 155 | finish_wait(&ws->wait, &wait); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 156 | return tag; |
| 157 | } |
| 158 | |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 159 | static unsigned int __blk_mq_get_tag(struct blk_mq_alloc_data *data) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 160 | { |
| 161 | int tag; |
| 162 | |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 163 | tag = bt_get(data, &data->hctx->tags->bitmap_tags, data->hctx, |
Omar Sandoval | 40aabb6 | 2016-09-17 01:28:23 -0700 | [diff] [blame] | 164 | data->hctx->tags); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 165 | if (tag >= 0) |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 166 | return tag + data->hctx->tags->nr_reserved_tags; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 167 | |
| 168 | return BLK_MQ_TAG_FAIL; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 169 | } |
| 170 | |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 171 | static unsigned int __blk_mq_get_reserved_tag(struct blk_mq_alloc_data *data) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 172 | { |
Omar Sandoval | 40aabb6 | 2016-09-17 01:28:23 -0700 | [diff] [blame] | 173 | int tag; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 174 | |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 175 | if (unlikely(!data->hctx->tags->nr_reserved_tags)) { |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 176 | WARN_ON_ONCE(1); |
| 177 | return BLK_MQ_TAG_FAIL; |
| 178 | } |
| 179 | |
Omar Sandoval | 40aabb6 | 2016-09-17 01:28:23 -0700 | [diff] [blame] | 180 | tag = bt_get(data, &data->hctx->tags->breserved_tags, NULL, |
| 181 | data->hctx->tags); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 182 | if (tag < 0) |
| 183 | return BLK_MQ_TAG_FAIL; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 184 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 185 | return tag; |
| 186 | } |
| 187 | |
Ming Lei | cb96a42 | 2014-06-01 00:43:37 +0800 | [diff] [blame] | 188 | unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 189 | { |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 190 | if (data->flags & BLK_MQ_REQ_RESERVED) |
| 191 | return __blk_mq_get_reserved_tag(data); |
| 192 | return __blk_mq_get_tag(data); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 193 | } |
| 194 | |
Omar Sandoval | 40aabb6 | 2016-09-17 01:28:23 -0700 | [diff] [blame] | 195 | void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, |
| 196 | unsigned int tag) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 197 | { |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 198 | struct blk_mq_tags *tags = hctx->tags; |
| 199 | |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 200 | if (tag >= tags->nr_reserved_tags) { |
| 201 | const int real_tag = tag - tags->nr_reserved_tags; |
| 202 | |
Jens Axboe | 70114c3 | 2014-11-24 15:52:30 -0700 | [diff] [blame] | 203 | BUG_ON(real_tag >= tags->nr_tags); |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 204 | sbitmap_queue_clear(&tags->bitmap_tags, real_tag, ctx->cpu); |
Jens Axboe | 70114c3 | 2014-11-24 15:52:30 -0700 | [diff] [blame] | 205 | } else { |
| 206 | BUG_ON(tag >= tags->nr_reserved_tags); |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 207 | sbitmap_queue_clear(&tags->breserved_tags, tag, ctx->cpu); |
Jens Axboe | 70114c3 | 2014-11-24 15:52:30 -0700 | [diff] [blame] | 208 | } |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 209 | } |
| 210 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 211 | struct bt_iter_data { |
| 212 | struct blk_mq_hw_ctx *hctx; |
| 213 | busy_iter_fn *fn; |
| 214 | void *data; |
| 215 | bool reserved; |
| 216 | }; |
| 217 | |
| 218 | static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 219 | { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 220 | struct bt_iter_data *iter_data = data; |
| 221 | struct blk_mq_hw_ctx *hctx = iter_data->hctx; |
| 222 | struct blk_mq_tags *tags = hctx->tags; |
| 223 | bool reserved = iter_data->reserved; |
Christoph Hellwig | 81481eb | 2014-09-13 16:40:11 -0700 | [diff] [blame] | 224 | struct request *rq; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 225 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 226 | if (!reserved) |
| 227 | bitnr += tags->nr_reserved_tags; |
| 228 | rq = tags->rqs[bitnr]; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 229 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 230 | if (rq->q == hctx->queue) |
| 231 | iter_data->fn(hctx, rq, iter_data->data, reserved); |
| 232 | return true; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 233 | } |
| 234 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 235 | static void bt_for_each(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt, |
| 236 | busy_iter_fn *fn, void *data, bool reserved) |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 237 | { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 238 | struct bt_iter_data iter_data = { |
| 239 | .hctx = hctx, |
| 240 | .fn = fn, |
| 241 | .data = data, |
| 242 | .reserved = reserved, |
| 243 | }; |
| 244 | |
| 245 | sbitmap_for_each_set(&bt->sb, bt_iter, &iter_data); |
| 246 | } |
| 247 | |
| 248 | struct bt_tags_iter_data { |
| 249 | struct blk_mq_tags *tags; |
| 250 | busy_tag_iter_fn *fn; |
| 251 | void *data; |
| 252 | bool reserved; |
| 253 | }; |
| 254 | |
| 255 | static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) |
| 256 | { |
| 257 | struct bt_tags_iter_data *iter_data = data; |
| 258 | struct blk_mq_tags *tags = iter_data->tags; |
| 259 | bool reserved = iter_data->reserved; |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 260 | struct request *rq; |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 261 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 262 | if (!reserved) |
| 263 | bitnr += tags->nr_reserved_tags; |
| 264 | rq = tags->rqs[bitnr]; |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 265 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 266 | iter_data->fn(rq, iter_data->data, reserved); |
| 267 | return true; |
| 268 | } |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 269 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 270 | static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, |
| 271 | busy_tag_iter_fn *fn, void *data, bool reserved) |
| 272 | { |
| 273 | struct bt_tags_iter_data iter_data = { |
| 274 | .tags = tags, |
| 275 | .fn = fn, |
| 276 | .data = data, |
| 277 | .reserved = reserved, |
| 278 | }; |
| 279 | |
| 280 | if (tags->rqs) |
| 281 | sbitmap_for_each_set(&bt->sb, bt_tags_iter, &iter_data); |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 282 | } |
| 283 | |
Sagi Grimberg | e8f1e16 | 2016-03-10 13:58:49 +0200 | [diff] [blame] | 284 | static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, |
| 285 | busy_tag_iter_fn *fn, void *priv) |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 286 | { |
| 287 | if (tags->nr_reserved_tags) |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 288 | bt_tags_for_each(tags, &tags->breserved_tags, fn, priv, true); |
| 289 | bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, false); |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 290 | } |
Keith Busch | f26cdc8 | 2015-06-01 09:29:53 -0600 | [diff] [blame] | 291 | |
Sagi Grimberg | e048948 | 2016-03-10 13:58:46 +0200 | [diff] [blame] | 292 | void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, |
| 293 | busy_tag_iter_fn *fn, void *priv) |
| 294 | { |
| 295 | int i; |
| 296 | |
| 297 | for (i = 0; i < tagset->nr_hw_queues; i++) { |
| 298 | if (tagset->tags && tagset->tags[i]) |
| 299 | blk_mq_all_tag_busy_iter(tagset->tags[i], fn, priv); |
| 300 | } |
| 301 | } |
| 302 | EXPORT_SYMBOL(blk_mq_tagset_busy_iter); |
| 303 | |
Sagi Grimberg | 486cf98 | 2016-07-06 21:55:48 +0900 | [diff] [blame] | 304 | int blk_mq_reinit_tagset(struct blk_mq_tag_set *set) |
| 305 | { |
| 306 | int i, j, ret = 0; |
| 307 | |
| 308 | if (!set->ops->reinit_request) |
| 309 | goto out; |
| 310 | |
| 311 | for (i = 0; i < set->nr_hw_queues; i++) { |
| 312 | struct blk_mq_tags *tags = set->tags[i]; |
| 313 | |
| 314 | for (j = 0; j < tags->nr_tags; j++) { |
| 315 | if (!tags->rqs[j]) |
| 316 | continue; |
| 317 | |
| 318 | ret = set->ops->reinit_request(set->driver_data, |
| 319 | tags->rqs[j]); |
| 320 | if (ret) |
| 321 | goto out; |
| 322 | } |
| 323 | } |
| 324 | |
| 325 | out: |
| 326 | return ret; |
| 327 | } |
| 328 | EXPORT_SYMBOL_GPL(blk_mq_reinit_tagset); |
| 329 | |
Christoph Hellwig | 0bf6cd5 | 2015-09-27 21:01:51 +0200 | [diff] [blame] | 330 | void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, |
Christoph Hellwig | 81481eb | 2014-09-13 16:40:11 -0700 | [diff] [blame] | 331 | void *priv) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 332 | { |
Christoph Hellwig | 0bf6cd5 | 2015-09-27 21:01:51 +0200 | [diff] [blame] | 333 | struct blk_mq_hw_ctx *hctx; |
| 334 | int i; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 335 | |
Christoph Hellwig | 0bf6cd5 | 2015-09-27 21:01:51 +0200 | [diff] [blame] | 336 | |
| 337 | queue_for_each_hw_ctx(q, hctx, i) { |
| 338 | struct blk_mq_tags *tags = hctx->tags; |
| 339 | |
| 340 | /* |
| 341 | * If not software queues are currently mapped to this |
| 342 | * hardware queue, there's nothing to check |
| 343 | */ |
| 344 | if (!blk_mq_hw_queue_mapped(hctx)) |
| 345 | continue; |
| 346 | |
| 347 | if (tags->nr_reserved_tags) |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 348 | bt_for_each(hctx, &tags->breserved_tags, fn, priv, true); |
| 349 | bt_for_each(hctx, &tags->bitmap_tags, fn, priv, false); |
Christoph Hellwig | 0bf6cd5 | 2015-09-27 21:01:51 +0200 | [diff] [blame] | 350 | } |
| 351 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 352 | } |
| 353 | |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 354 | static unsigned int bt_unused_tags(const struct sbitmap_queue *bt) |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 355 | { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 356 | return bt->sb.depth - sbitmap_weight(&bt->sb); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 357 | } |
| 358 | |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 359 | static int bt_alloc(struct sbitmap_queue *bt, unsigned int depth, |
| 360 | bool round_robin, int node) |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 361 | { |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 362 | return sbitmap_queue_init_node(bt, depth, -1, round_robin, GFP_KERNEL, |
| 363 | node); |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 364 | } |
| 365 | |
| 366 | static struct blk_mq_tags *blk_mq_init_bitmap_tags(struct blk_mq_tags *tags, |
Shaohua Li | 24391c0 | 2015-01-23 14:18:00 -0700 | [diff] [blame] | 367 | int node, int alloc_policy) |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 368 | { |
| 369 | unsigned int depth = tags->nr_tags - tags->nr_reserved_tags; |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 370 | bool round_robin = alloc_policy == BLK_TAG_ALLOC_RR; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 371 | |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 372 | if (bt_alloc(&tags->bitmap_tags, depth, round_robin, node)) |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 373 | goto free_tags; |
Omar Sandoval | f4a644d | 2016-09-17 01:28:24 -0700 | [diff] [blame] | 374 | if (bt_alloc(&tags->breserved_tags, tags->nr_reserved_tags, round_robin, |
| 375 | node)) |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 376 | goto free_bitmap_tags; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 377 | |
| 378 | return tags; |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 379 | free_bitmap_tags: |
| 380 | sbitmap_queue_free(&tags->bitmap_tags); |
| 381 | free_tags: |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 382 | kfree(tags); |
| 383 | return NULL; |
| 384 | } |
| 385 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 386 | struct blk_mq_tags *blk_mq_init_tags(unsigned int total_tags, |
Shaohua Li | 24391c0 | 2015-01-23 14:18:00 -0700 | [diff] [blame] | 387 | unsigned int reserved_tags, |
| 388 | int node, int alloc_policy) |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 389 | { |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 390 | struct blk_mq_tags *tags; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 391 | |
| 392 | if (total_tags > BLK_MQ_TAG_MAX) { |
| 393 | pr_err("blk-mq: tag depth too large\n"); |
| 394 | return NULL; |
| 395 | } |
| 396 | |
| 397 | tags = kzalloc_node(sizeof(*tags), GFP_KERNEL, node); |
| 398 | if (!tags) |
| 399 | return NULL; |
| 400 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 401 | tags->nr_tags = total_tags; |
| 402 | tags->nr_reserved_tags = reserved_tags; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 403 | |
Shaohua Li | 24391c0 | 2015-01-23 14:18:00 -0700 | [diff] [blame] | 404 | return blk_mq_init_bitmap_tags(tags, node, alloc_policy); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 405 | } |
| 406 | |
| 407 | void blk_mq_free_tags(struct blk_mq_tags *tags) |
| 408 | { |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 409 | sbitmap_queue_free(&tags->bitmap_tags); |
| 410 | sbitmap_queue_free(&tags->breserved_tags); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 411 | kfree(tags); |
| 412 | } |
| 413 | |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 414 | int blk_mq_tag_update_depth(struct blk_mq_tags *tags, unsigned int tdepth) |
| 415 | { |
| 416 | tdepth -= tags->nr_reserved_tags; |
| 417 | if (tdepth > tags->nr_tags) |
| 418 | return -EINVAL; |
| 419 | |
| 420 | /* |
| 421 | * Don't need (or can't) update reserved tags here, they remain |
| 422 | * static and should never need resizing. |
| 423 | */ |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 424 | sbitmap_queue_resize(&tags->bitmap_tags, tdepth); |
| 425 | |
Jens Axboe | aed3ea9 | 2014-12-22 14:04:42 -0700 | [diff] [blame] | 426 | blk_mq_tag_wakeup_all(tags, false); |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 427 | return 0; |
| 428 | } |
| 429 | |
Bart Van Assche | 205fb5f | 2014-10-30 14:45:11 +0100 | [diff] [blame] | 430 | /** |
| 431 | * blk_mq_unique_tag() - return a tag that is unique queue-wide |
| 432 | * @rq: request for which to compute a unique tag |
| 433 | * |
| 434 | * The tag field in struct request is unique per hardware queue but not over |
| 435 | * all hardware queues. Hence this function that returns a tag with the |
| 436 | * hardware context index in the upper bits and the per hardware queue tag in |
| 437 | * the lower bits. |
| 438 | * |
| 439 | * Note: When called for a request that is queued on a non-multiqueue request |
| 440 | * queue, the hardware context index is set to zero. |
| 441 | */ |
| 442 | u32 blk_mq_unique_tag(struct request *rq) |
| 443 | { |
| 444 | struct request_queue *q = rq->q; |
| 445 | struct blk_mq_hw_ctx *hctx; |
| 446 | int hwq = 0; |
| 447 | |
| 448 | if (q->mq_ops) { |
Christoph Hellwig | 7d7e0f9 | 2016-09-14 16:18:54 +0200 | [diff] [blame] | 449 | hctx = blk_mq_map_queue(q, rq->mq_ctx->cpu); |
Bart Van Assche | 205fb5f | 2014-10-30 14:45:11 +0100 | [diff] [blame] | 450 | hwq = hctx->queue_num; |
| 451 | } |
| 452 | |
| 453 | return (hwq << BLK_MQ_UNIQUE_TAG_BITS) | |
| 454 | (rq->tag & BLK_MQ_UNIQUE_TAG_MASK); |
| 455 | } |
| 456 | EXPORT_SYMBOL(blk_mq_unique_tag); |
| 457 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 458 | ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page) |
| 459 | { |
| 460 | char *orig_page = page; |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 461 | unsigned int free, res; |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 462 | |
| 463 | if (!tags) |
| 464 | return 0; |
| 465 | |
Jens Axboe | 59d13bf | 2014-05-09 13:41:15 -0600 | [diff] [blame] | 466 | page += sprintf(page, "nr_tags=%u, reserved_tags=%u, " |
| 467 | "bits_per_word=%u\n", |
| 468 | tags->nr_tags, tags->nr_reserved_tags, |
Omar Sandoval | 8845964 | 2016-09-17 08:38:44 -0600 | [diff] [blame] | 469 | 1U << tags->bitmap_tags.sb.shift); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 470 | |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 471 | free = bt_unused_tags(&tags->bitmap_tags); |
| 472 | res = bt_unused_tags(&tags->breserved_tags); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 473 | |
Jens Axboe | 4bb659b | 2014-05-09 09:36:49 -0600 | [diff] [blame] | 474 | page += sprintf(page, "nr_free=%u, nr_reserved=%u\n", free, res); |
Jens Axboe | 0d2602c | 2014-05-13 15:10:52 -0600 | [diff] [blame] | 475 | page += sprintf(page, "active_queues=%u\n", atomic_read(&tags->active_queues)); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 476 | |
| 477 | return page - orig_page; |
| 478 | } |