Commit | Line | Data |
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bae9a0aa | 1 | // SPDX-License-Identifier: GPL-2.0-only |
3b1a94c8 DLM |
2 | /* |
3 | * Copyright (C) 2017 Western Digital Corporation or its affiliates. | |
4 | * | |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm-zoned.h" | |
9 | ||
10 | #include <linux/module.h> | |
11 | ||
12 | #define DM_MSG_PREFIX "zoned reclaim" | |
13 | ||
14 | struct dmz_reclaim { | |
15 | struct dmz_metadata *metadata; | |
3b1a94c8 DLM |
16 | |
17 | struct delayed_work work; | |
18 | struct workqueue_struct *wq; | |
19 | ||
20 | struct dm_kcopyd_client *kc; | |
21 | struct dm_kcopyd_throttle kc_throttle; | |
22 | int kc_err; | |
23 | ||
f97809ae HR |
24 | int dev_idx; |
25 | ||
3b1a94c8 DLM |
26 | unsigned long flags; |
27 | ||
28 | /* Last target access time */ | |
29 | unsigned long atime; | |
30 | }; | |
31 | ||
32 | /* | |
33 | * Reclaim state flags. | |
34 | */ | |
35 | enum { | |
36 | DMZ_RECLAIM_KCOPY, | |
37 | }; | |
38 | ||
39 | /* | |
40 | * Number of seconds of target BIO inactivity to consider the target idle. | |
41 | */ | |
75d66ffb | 42 | #define DMZ_IDLE_PERIOD (10UL * HZ) |
3b1a94c8 DLM |
43 | |
44 | /* | |
45 | * Percentage of unmapped (free) random zones below which reclaim starts | |
46 | * even if the target is busy. | |
47 | */ | |
34f5affd | 48 | #define DMZ_RECLAIM_LOW_UNMAP_ZONES 30 |
3b1a94c8 DLM |
49 | |
50 | /* | |
51 | * Percentage of unmapped (free) random zones above which reclaim will | |
52 | * stop if the target is busy. | |
53 | */ | |
34f5affd | 54 | #define DMZ_RECLAIM_HIGH_UNMAP_ZONES 50 |
3b1a94c8 DLM |
55 | |
56 | /* | |
57 | * Align a sequential zone write pointer to chunk_block. | |
58 | */ | |
59 | static int dmz_reclaim_align_wp(struct dmz_reclaim *zrc, struct dm_zone *zone, | |
60 | sector_t block) | |
61 | { | |
62 | struct dmz_metadata *zmd = zrc->metadata; | |
8f22272a | 63 | struct dmz_dev *dev = zone->dev; |
3b1a94c8 DLM |
64 | sector_t wp_block = zone->wp_block; |
65 | unsigned int nr_blocks; | |
66 | int ret; | |
67 | ||
68 | if (wp_block == block) | |
69 | return 0; | |
70 | ||
71 | if (wp_block > block) | |
72 | return -EIO; | |
73 | ||
74 | /* | |
75 | * Zeroout the space between the write | |
76 | * pointer and the requested position. | |
77 | */ | |
78 | nr_blocks = block - wp_block; | |
6c805f77 | 79 | ret = blkdev_issue_zeroout(dev->bdev, |
3b1a94c8 | 80 | dmz_start_sect(zmd, zone) + dmz_blk2sect(wp_block), |
4218a955 | 81 | dmz_blk2sect(nr_blocks), GFP_NOIO, 0); |
3b1a94c8 | 82 | if (ret) { |
6c805f77 | 83 | dmz_dev_err(dev, |
3b1a94c8 | 84 | "Align zone %u wp %llu to %llu (wp+%u) blocks failed %d", |
b7122873 | 85 | zone->id, (unsigned long long)wp_block, |
3b1a94c8 | 86 | (unsigned long long)block, nr_blocks, ret); |
6c805f77 | 87 | dmz_check_bdev(dev); |
3b1a94c8 DLM |
88 | return ret; |
89 | } | |
90 | ||
91 | zone->wp_block = block; | |
92 | ||
93 | return 0; | |
94 | } | |
95 | ||
96 | /* | |
97 | * dm_kcopyd_copy end notification. | |
98 | */ | |
99 | static void dmz_reclaim_kcopy_end(int read_err, unsigned long write_err, | |
100 | void *context) | |
101 | { | |
102 | struct dmz_reclaim *zrc = context; | |
103 | ||
104 | if (read_err || write_err) | |
105 | zrc->kc_err = -EIO; | |
106 | else | |
107 | zrc->kc_err = 0; | |
108 | ||
109 | clear_bit_unlock(DMZ_RECLAIM_KCOPY, &zrc->flags); | |
110 | smp_mb__after_atomic(); | |
111 | wake_up_bit(&zrc->flags, DMZ_RECLAIM_KCOPY); | |
112 | } | |
113 | ||
114 | /* | |
115 | * Copy valid blocks of src_zone into dst_zone. | |
116 | */ | |
117 | static int dmz_reclaim_copy(struct dmz_reclaim *zrc, | |
118 | struct dm_zone *src_zone, struct dm_zone *dst_zone) | |
119 | { | |
120 | struct dmz_metadata *zmd = zrc->metadata; | |
3b1a94c8 DLM |
121 | struct dm_io_region src, dst; |
122 | sector_t block = 0, end_block; | |
123 | sector_t nr_blocks; | |
124 | sector_t src_zone_block; | |
125 | sector_t dst_zone_block; | |
126 | unsigned long flags = 0; | |
127 | int ret; | |
128 | ||
129 | if (dmz_is_seq(src_zone)) | |
130 | end_block = src_zone->wp_block; | |
131 | else | |
36820560 | 132 | end_block = dmz_zone_nr_blocks(zmd); |
3b1a94c8 DLM |
133 | src_zone_block = dmz_start_block(zmd, src_zone); |
134 | dst_zone_block = dmz_start_block(zmd, dst_zone); | |
135 | ||
136 | if (dmz_is_seq(dst_zone)) | |
db2351eb | 137 | flags |= BIT(DM_KCOPYD_WRITE_SEQ); |
3b1a94c8 DLM |
138 | |
139 | while (block < end_block) { | |
8f22272a | 140 | if (src_zone->dev->flags & DMZ_BDEV_DYING) |
6c805f77 | 141 | return -EIO; |
8f22272a | 142 | if (dst_zone->dev->flags & DMZ_BDEV_DYING) |
75d66ffb DF |
143 | return -EIO; |
144 | ||
a16b7dee HR |
145 | if (dmz_reclaim_should_terminate(src_zone)) |
146 | return -EINTR; | |
147 | ||
3b1a94c8 DLM |
148 | /* Get a valid region from the source zone */ |
149 | ret = dmz_first_valid_block(zmd, src_zone, &block); | |
150 | if (ret <= 0) | |
151 | return ret; | |
152 | nr_blocks = ret; | |
153 | ||
154 | /* | |
155 | * If we are writing in a sequential zone, we must make sure | |
156 | * that writes are sequential. So Zeroout any eventual hole | |
157 | * between writes. | |
158 | */ | |
159 | if (dmz_is_seq(dst_zone)) { | |
160 | ret = dmz_reclaim_align_wp(zrc, dst_zone, block); | |
161 | if (ret) | |
162 | return ret; | |
163 | } | |
164 | ||
8f22272a | 165 | src.bdev = src_zone->dev->bdev; |
3b1a94c8 DLM |
166 | src.sector = dmz_blk2sect(src_zone_block + block); |
167 | src.count = dmz_blk2sect(nr_blocks); | |
168 | ||
8f22272a | 169 | dst.bdev = dst_zone->dev->bdev; |
3b1a94c8 DLM |
170 | dst.sector = dmz_blk2sect(dst_zone_block + block); |
171 | dst.count = src.count; | |
172 | ||
173 | /* Copy the valid region */ | |
174 | set_bit(DMZ_RECLAIM_KCOPY, &zrc->flags); | |
7209049d MS |
175 | dm_kcopyd_copy(zrc->kc, &src, 1, &dst, flags, |
176 | dmz_reclaim_kcopy_end, zrc); | |
3b1a94c8 DLM |
177 | |
178 | /* Wait for copy to complete */ | |
179 | wait_on_bit_io(&zrc->flags, DMZ_RECLAIM_KCOPY, | |
180 | TASK_UNINTERRUPTIBLE); | |
181 | if (zrc->kc_err) | |
182 | return zrc->kc_err; | |
183 | ||
184 | block += nr_blocks; | |
185 | if (dmz_is_seq(dst_zone)) | |
186 | dst_zone->wp_block = block; | |
187 | } | |
188 | ||
189 | return 0; | |
190 | } | |
191 | ||
192 | /* | |
193 | * Move valid blocks of dzone buffer zone into dzone (after its write pointer) | |
194 | * and free the buffer zone. | |
195 | */ | |
196 | static int dmz_reclaim_buf(struct dmz_reclaim *zrc, struct dm_zone *dzone) | |
197 | { | |
198 | struct dm_zone *bzone = dzone->bzone; | |
199 | sector_t chunk_block = dzone->wp_block; | |
200 | struct dmz_metadata *zmd = zrc->metadata; | |
201 | int ret; | |
202 | ||
f97809ae HR |
203 | DMDEBUG("(%s/%u): Chunk %u, move buf zone %u (weight %u) to data zone %u (weight %u)", |
204 | dmz_metadata_label(zmd), zrc->dev_idx, | |
6c805f77 HR |
205 | dzone->chunk, bzone->id, dmz_weight(bzone), |
206 | dzone->id, dmz_weight(dzone)); | |
3b1a94c8 DLM |
207 | |
208 | /* Flush data zone into the buffer zone */ | |
209 | ret = dmz_reclaim_copy(zrc, bzone, dzone); | |
210 | if (ret < 0) | |
211 | return ret; | |
212 | ||
213 | dmz_lock_flush(zmd); | |
214 | ||
215 | /* Validate copied blocks */ | |
216 | ret = dmz_merge_valid_blocks(zmd, bzone, dzone, chunk_block); | |
217 | if (ret == 0) { | |
218 | /* Free the buffer zone */ | |
36820560 | 219 | dmz_invalidate_blocks(zmd, bzone, 0, dmz_zone_nr_blocks(zmd)); |
3b1a94c8 DLM |
220 | dmz_lock_map(zmd); |
221 | dmz_unmap_zone(zmd, bzone); | |
222 | dmz_unlock_zone_reclaim(dzone); | |
223 | dmz_free_zone(zmd, bzone); | |
224 | dmz_unlock_map(zmd); | |
225 | } | |
226 | ||
227 | dmz_unlock_flush(zmd); | |
228 | ||
b234c6d7 | 229 | return ret; |
3b1a94c8 DLM |
230 | } |
231 | ||
232 | /* | |
233 | * Merge valid blocks of dzone into its buffer zone and free dzone. | |
234 | */ | |
235 | static int dmz_reclaim_seq_data(struct dmz_reclaim *zrc, struct dm_zone *dzone) | |
236 | { | |
237 | unsigned int chunk = dzone->chunk; | |
238 | struct dm_zone *bzone = dzone->bzone; | |
239 | struct dmz_metadata *zmd = zrc->metadata; | |
240 | int ret = 0; | |
241 | ||
f97809ae HR |
242 | DMDEBUG("(%s/%u): Chunk %u, move data zone %u (weight %u) to buf zone %u (weight %u)", |
243 | dmz_metadata_label(zmd), zrc->dev_idx, | |
6c805f77 HR |
244 | chunk, dzone->id, dmz_weight(dzone), |
245 | bzone->id, dmz_weight(bzone)); | |
3b1a94c8 DLM |
246 | |
247 | /* Flush data zone into the buffer zone */ | |
248 | ret = dmz_reclaim_copy(zrc, dzone, bzone); | |
249 | if (ret < 0) | |
250 | return ret; | |
251 | ||
252 | dmz_lock_flush(zmd); | |
253 | ||
254 | /* Validate copied blocks */ | |
255 | ret = dmz_merge_valid_blocks(zmd, dzone, bzone, 0); | |
256 | if (ret == 0) { | |
257 | /* | |
258 | * Free the data zone and remap the chunk to | |
259 | * the buffer zone. | |
260 | */ | |
36820560 | 261 | dmz_invalidate_blocks(zmd, dzone, 0, dmz_zone_nr_blocks(zmd)); |
3b1a94c8 DLM |
262 | dmz_lock_map(zmd); |
263 | dmz_unmap_zone(zmd, bzone); | |
264 | dmz_unmap_zone(zmd, dzone); | |
265 | dmz_unlock_zone_reclaim(dzone); | |
266 | dmz_free_zone(zmd, dzone); | |
267 | dmz_map_zone(zmd, bzone, chunk); | |
268 | dmz_unlock_map(zmd); | |
269 | } | |
270 | ||
271 | dmz_unlock_flush(zmd); | |
272 | ||
b234c6d7 | 273 | return ret; |
3b1a94c8 DLM |
274 | } |
275 | ||
276 | /* | |
277 | * Move valid blocks of the random data zone dzone into a free sequential zone. | |
278 | * Once blocks are moved, remap the zone chunk to the sequential zone. | |
279 | */ | |
280 | static int dmz_reclaim_rnd_data(struct dmz_reclaim *zrc, struct dm_zone *dzone) | |
281 | { | |
282 | unsigned int chunk = dzone->chunk; | |
283 | struct dm_zone *szone = NULL; | |
284 | struct dmz_metadata *zmd = zrc->metadata; | |
285 | int ret; | |
c5c78859 | 286 | int alloc_flags = DMZ_ALLOC_SEQ; |
3b1a94c8 | 287 | |
90a9b869 | 288 | /* Get a free random or sequential zone */ |
3b1a94c8 | 289 | dmz_lock_map(zmd); |
c5c78859 | 290 | again: |
22c1ef66 HR |
291 | szone = dmz_alloc_zone(zmd, zrc->dev_idx, |
292 | alloc_flags | DMZ_ALLOC_RECLAIM); | |
c5c78859 HR |
293 | if (!szone && alloc_flags == DMZ_ALLOC_SEQ && dmz_nr_cache_zones(zmd)) { |
294 | alloc_flags = DMZ_ALLOC_RND; | |
295 | goto again; | |
296 | } | |
3b1a94c8 DLM |
297 | dmz_unlock_map(zmd); |
298 | if (!szone) | |
299 | return -ENOSPC; | |
300 | ||
f97809ae HR |
301 | DMDEBUG("(%s/%u): Chunk %u, move %s zone %u (weight %u) to %s zone %u", |
302 | dmz_metadata_label(zmd), zrc->dev_idx, chunk, | |
34f5affd HR |
303 | dmz_is_cache(dzone) ? "cache" : "rnd", |
304 | dzone->id, dmz_weight(dzone), | |
305 | dmz_is_rnd(szone) ? "rnd" : "seq", szone->id); | |
3b1a94c8 DLM |
306 | |
307 | /* Flush the random data zone into the sequential zone */ | |
308 | ret = dmz_reclaim_copy(zrc, dzone, szone); | |
309 | ||
310 | dmz_lock_flush(zmd); | |
311 | ||
312 | if (ret == 0) { | |
313 | /* Validate copied blocks */ | |
314 | ret = dmz_copy_valid_blocks(zmd, dzone, szone); | |
315 | } | |
316 | if (ret) { | |
317 | /* Free the sequential zone */ | |
318 | dmz_lock_map(zmd); | |
319 | dmz_free_zone(zmd, szone); | |
320 | dmz_unlock_map(zmd); | |
321 | } else { | |
322 | /* Free the data zone and remap the chunk */ | |
36820560 | 323 | dmz_invalidate_blocks(zmd, dzone, 0, dmz_zone_nr_blocks(zmd)); |
3b1a94c8 DLM |
324 | dmz_lock_map(zmd); |
325 | dmz_unmap_zone(zmd, dzone); | |
326 | dmz_unlock_zone_reclaim(dzone); | |
327 | dmz_free_zone(zmd, dzone); | |
328 | dmz_map_zone(zmd, szone, chunk); | |
329 | dmz_unlock_map(zmd); | |
330 | } | |
331 | ||
332 | dmz_unlock_flush(zmd); | |
333 | ||
b234c6d7 | 334 | return ret; |
3b1a94c8 DLM |
335 | } |
336 | ||
337 | /* | |
338 | * Reclaim an empty zone. | |
339 | */ | |
340 | static void dmz_reclaim_empty(struct dmz_reclaim *zrc, struct dm_zone *dzone) | |
341 | { | |
342 | struct dmz_metadata *zmd = zrc->metadata; | |
343 | ||
344 | dmz_lock_flush(zmd); | |
345 | dmz_lock_map(zmd); | |
346 | dmz_unmap_zone(zmd, dzone); | |
347 | dmz_unlock_zone_reclaim(dzone); | |
348 | dmz_free_zone(zmd, dzone); | |
349 | dmz_unlock_map(zmd); | |
350 | dmz_unlock_flush(zmd); | |
351 | } | |
352 | ||
90a9b869 HR |
353 | /* |
354 | * Test if the target device is idle. | |
355 | */ | |
356 | static inline int dmz_target_idle(struct dmz_reclaim *zrc) | |
357 | { | |
358 | return time_is_before_jiffies(zrc->atime + DMZ_IDLE_PERIOD); | |
359 | } | |
360 | ||
3b1a94c8 DLM |
361 | /* |
362 | * Find a candidate zone for reclaim and process it. | |
363 | */ | |
b234c6d7 | 364 | static int dmz_do_reclaim(struct dmz_reclaim *zrc) |
3b1a94c8 DLM |
365 | { |
366 | struct dmz_metadata *zmd = zrc->metadata; | |
367 | struct dm_zone *dzone; | |
368 | struct dm_zone *rzone; | |
369 | unsigned long start; | |
370 | int ret; | |
371 | ||
372 | /* Get a data zone */ | |
69875d44 HR |
373 | dzone = dmz_get_zone_for_reclaim(zmd, zrc->dev_idx, |
374 | dmz_target_idle(zrc)); | |
c3ff479d | 375 | if (!dzone) { |
f97809ae HR |
376 | DMDEBUG("(%s/%u): No zone found to reclaim", |
377 | dmz_metadata_label(zmd), zrc->dev_idx); | |
489dc0f0 | 378 | return -EBUSY; |
c3ff479d | 379 | } |
c69cb1d1 | 380 | rzone = dzone; |
3b1a94c8 DLM |
381 | |
382 | start = jiffies; | |
34f5affd | 383 | if (dmz_is_cache(dzone) || dmz_is_rnd(dzone)) { |
3b1a94c8 DLM |
384 | if (!dmz_weight(dzone)) { |
385 | /* Empty zone */ | |
386 | dmz_reclaim_empty(zrc, dzone); | |
387 | ret = 0; | |
388 | } else { | |
389 | /* | |
390 | * Reclaim the random data zone by moving its | |
391 | * valid data blocks to a free sequential zone. | |
392 | */ | |
393 | ret = dmz_reclaim_rnd_data(zrc, dzone); | |
394 | } | |
3b1a94c8 DLM |
395 | } else { |
396 | struct dm_zone *bzone = dzone->bzone; | |
397 | sector_t chunk_block = 0; | |
398 | ||
399 | ret = dmz_first_valid_block(zmd, bzone, &chunk_block); | |
400 | if (ret < 0) | |
401 | goto out; | |
402 | ||
403 | if (ret == 0 || chunk_block >= dzone->wp_block) { | |
404 | /* | |
405 | * The buffer zone is empty or its valid blocks are | |
406 | * after the data zone write pointer. | |
407 | */ | |
408 | ret = dmz_reclaim_buf(zrc, dzone); | |
409 | rzone = bzone; | |
410 | } else { | |
411 | /* | |
412 | * Reclaim the data zone by merging it into the | |
413 | * buffer zone so that the buffer zone itself can | |
414 | * be later reclaimed. | |
415 | */ | |
416 | ret = dmz_reclaim_seq_data(zrc, dzone); | |
3b1a94c8 DLM |
417 | } |
418 | } | |
419 | out: | |
420 | if (ret) { | |
c3ff479d | 421 | if (ret == -EINTR) |
f97809ae HR |
422 | DMDEBUG("(%s/%u): reclaim zone %u interrupted", |
423 | dmz_metadata_label(zmd), zrc->dev_idx, | |
424 | rzone->id); | |
c3ff479d | 425 | else |
f97809ae HR |
426 | DMDEBUG("(%s/%u): Failed to reclaim zone %u, err %d", |
427 | dmz_metadata_label(zmd), zrc->dev_idx, | |
428 | rzone->id, ret); | |
3b1a94c8 | 429 | dmz_unlock_zone_reclaim(dzone); |
b234c6d7 | 430 | return ret; |
3b1a94c8 DLM |
431 | } |
432 | ||
b234c6d7 DF |
433 | ret = dmz_flush_metadata(zrc->metadata); |
434 | if (ret) { | |
f97809ae HR |
435 | DMDEBUG("(%s/%u): Metadata flush for zone %u failed, err %d", |
436 | dmz_metadata_label(zmd), zrc->dev_idx, rzone->id, ret); | |
b234c6d7 DF |
437 | return ret; |
438 | } | |
3b1a94c8 | 439 | |
f97809ae HR |
440 | DMDEBUG("(%s/%u): Reclaimed zone %u in %u ms", |
441 | dmz_metadata_label(zmd), zrc->dev_idx, | |
6c805f77 | 442 | rzone->id, jiffies_to_msecs(jiffies - start)); |
b234c6d7 | 443 | return 0; |
3b1a94c8 DLM |
444 | } |
445 | ||
34f5affd | 446 | static unsigned int dmz_reclaim_percentage(struct dmz_reclaim *zrc) |
3b1a94c8 DLM |
447 | { |
448 | struct dmz_metadata *zmd = zrc->metadata; | |
34f5affd | 449 | unsigned int nr_cache = dmz_nr_cache_zones(zmd); |
34f5affd | 450 | unsigned int nr_unmap, nr_zones; |
3b1a94c8 | 451 | |
34f5affd HR |
452 | if (nr_cache) { |
453 | nr_zones = nr_cache; | |
454 | nr_unmap = dmz_nr_unmap_cache_zones(zmd); | |
455 | } else { | |
bd82fdab HR |
456 | nr_zones = dmz_nr_rnd_zones(zmd, zrc->dev_idx); |
457 | nr_unmap = dmz_nr_unmap_rnd_zones(zmd, zrc->dev_idx); | |
34f5affd | 458 | } |
174364f6 DLM |
459 | if (nr_unmap <= 1) |
460 | return 0; | |
34f5affd HR |
461 | return nr_unmap * 100 / nr_zones; |
462 | } | |
463 | ||
464 | /* | |
465 | * Test if reclaim is necessary. | |
466 | */ | |
467 | static bool dmz_should_reclaim(struct dmz_reclaim *zrc, unsigned int p_unmap) | |
468 | { | |
f97809ae HR |
469 | unsigned int nr_reclaim; |
470 | ||
bd82fdab | 471 | nr_reclaim = dmz_nr_rnd_zones(zrc->metadata, zrc->dev_idx); |
90a9b869 | 472 | |
f97809ae HR |
473 | if (dmz_nr_cache_zones(zrc->metadata)) { |
474 | /* | |
475 | * The first device in a multi-device | |
476 | * setup only contains cache zones, so | |
477 | * never start reclaim there. | |
478 | */ | |
479 | if (zrc->dev_idx == 0) | |
480 | return false; | |
90a9b869 | 481 | nr_reclaim += dmz_nr_cache_zones(zrc->metadata); |
f97809ae | 482 | } |
90a9b869 | 483 | |
3b1a94c8 | 484 | /* Reclaim when idle */ |
90a9b869 | 485 | if (dmz_target_idle(zrc) && nr_reclaim) |
3b1a94c8 DLM |
486 | return true; |
487 | ||
34f5affd HR |
488 | /* If there are still plenty of cache zones, do not reclaim */ |
489 | if (p_unmap >= DMZ_RECLAIM_HIGH_UNMAP_ZONES) | |
3b1a94c8 DLM |
490 | return false; |
491 | ||
492 | /* | |
34f5affd | 493 | * If the percentage of unmapped cache zones is low, |
3b1a94c8 DLM |
494 | * reclaim even if the target is busy. |
495 | */ | |
34f5affd | 496 | return p_unmap <= DMZ_RECLAIM_LOW_UNMAP_ZONES; |
3b1a94c8 DLM |
497 | } |
498 | ||
499 | /* | |
500 | * Reclaim work function. | |
501 | */ | |
502 | static void dmz_reclaim_work(struct work_struct *work) | |
503 | { | |
504 | struct dmz_reclaim *zrc = container_of(work, struct dmz_reclaim, work.work); | |
505 | struct dmz_metadata *zmd = zrc->metadata; | |
ce34c9b4 | 506 | unsigned int p_unmap; |
b234c6d7 | 507 | int ret; |
3b1a94c8 | 508 | |
d0e21ce4 | 509 | if (dmz_dev_is_dying(zmd)) |
75d66ffb DF |
510 | return; |
511 | ||
34f5affd HR |
512 | p_unmap = dmz_reclaim_percentage(zrc); |
513 | if (!dmz_should_reclaim(zrc, p_unmap)) { | |
3b1a94c8 DLM |
514 | mod_delayed_work(zrc->wq, &zrc->work, DMZ_IDLE_PERIOD); |
515 | return; | |
516 | } | |
517 | ||
518 | /* | |
519 | * We need to start reclaiming random zones: set up zone copy | |
520 | * throttling to either go fast if we are very low on random zones | |
521 | * and slower if there are still some free random zones to avoid | |
522 | * as much as possible to negatively impact the user workload. | |
523 | */ | |
34f5affd | 524 | if (dmz_target_idle(zrc) || p_unmap < DMZ_RECLAIM_LOW_UNMAP_ZONES / 2) { |
3b1a94c8 DLM |
525 | /* Idle or very low percentage: go fast */ |
526 | zrc->kc_throttle.throttle = 100; | |
527 | } else { | |
528 | /* Busy but we still have some random zone: throttle */ | |
34f5affd | 529 | zrc->kc_throttle.throttle = min(75U, 100U - p_unmap / 2); |
3b1a94c8 DLM |
530 | } |
531 | ||
f97809ae HR |
532 | DMDEBUG("(%s/%u): Reclaim (%u): %s, %u%% free zones (%u/%u cache %u/%u random)", |
533 | dmz_metadata_label(zmd), zrc->dev_idx, | |
2234e732 HR |
534 | zrc->kc_throttle.throttle, |
535 | (dmz_target_idle(zrc) ? "Idle" : "Busy"), | |
34f5affd HR |
536 | p_unmap, dmz_nr_unmap_cache_zones(zmd), |
537 | dmz_nr_cache_zones(zmd), | |
bd82fdab HR |
538 | dmz_nr_unmap_rnd_zones(zmd, zrc->dev_idx), |
539 | dmz_nr_rnd_zones(zmd, zrc->dev_idx)); | |
3b1a94c8 | 540 | |
b234c6d7 | 541 | ret = dmz_do_reclaim(zrc); |
a16b7dee | 542 | if (ret && ret != -EINTR) { |
d0e21ce4 | 543 | if (!dmz_check_dev(zmd)) |
75d66ffb DF |
544 | return; |
545 | } | |
3b1a94c8 DLM |
546 | |
547 | dmz_schedule_reclaim(zrc); | |
548 | } | |
549 | ||
550 | /* | |
551 | * Initialize reclaim. | |
552 | */ | |
6c805f77 | 553 | int dmz_ctr_reclaim(struct dmz_metadata *zmd, |
f97809ae | 554 | struct dmz_reclaim **reclaim, int idx) |
3b1a94c8 DLM |
555 | { |
556 | struct dmz_reclaim *zrc; | |
557 | int ret; | |
558 | ||
559 | zrc = kzalloc(sizeof(struct dmz_reclaim), GFP_KERNEL); | |
560 | if (!zrc) | |
561 | return -ENOMEM; | |
562 | ||
3b1a94c8 DLM |
563 | zrc->metadata = zmd; |
564 | zrc->atime = jiffies; | |
f97809ae | 565 | zrc->dev_idx = idx; |
3b1a94c8 DLM |
566 | |
567 | /* Reclaim kcopyd client */ | |
568 | zrc->kc = dm_kcopyd_client_create(&zrc->kc_throttle); | |
569 | if (IS_ERR(zrc->kc)) { | |
570 | ret = PTR_ERR(zrc->kc); | |
571 | zrc->kc = NULL; | |
572 | goto err; | |
573 | } | |
574 | ||
575 | /* Reclaim work */ | |
576 | INIT_DELAYED_WORK(&zrc->work, dmz_reclaim_work); | |
f97809ae HR |
577 | zrc->wq = alloc_ordered_workqueue("dmz_rwq_%s_%d", WQ_MEM_RECLAIM, |
578 | dmz_metadata_label(zmd), idx); | |
3b1a94c8 DLM |
579 | if (!zrc->wq) { |
580 | ret = -ENOMEM; | |
581 | goto err; | |
582 | } | |
583 | ||
584 | *reclaim = zrc; | |
585 | queue_delayed_work(zrc->wq, &zrc->work, 0); | |
586 | ||
587 | return 0; | |
588 | err: | |
589 | if (zrc->kc) | |
590 | dm_kcopyd_client_destroy(zrc->kc); | |
591 | kfree(zrc); | |
592 | ||
593 | return ret; | |
594 | } | |
595 | ||
596 | /* | |
597 | * Terminate reclaim. | |
598 | */ | |
599 | void dmz_dtr_reclaim(struct dmz_reclaim *zrc) | |
600 | { | |
601 | cancel_delayed_work_sync(&zrc->work); | |
602 | destroy_workqueue(zrc->wq); | |
603 | dm_kcopyd_client_destroy(zrc->kc); | |
604 | kfree(zrc); | |
605 | } | |
606 | ||
607 | /* | |
608 | * Suspend reclaim. | |
609 | */ | |
610 | void dmz_suspend_reclaim(struct dmz_reclaim *zrc) | |
611 | { | |
612 | cancel_delayed_work_sync(&zrc->work); | |
613 | } | |
614 | ||
615 | /* | |
616 | * Resume reclaim. | |
617 | */ | |
618 | void dmz_resume_reclaim(struct dmz_reclaim *zrc) | |
619 | { | |
620 | queue_delayed_work(zrc->wq, &zrc->work, DMZ_IDLE_PERIOD); | |
621 | } | |
622 | ||
623 | /* | |
624 | * BIO accounting. | |
625 | */ | |
626 | void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc) | |
627 | { | |
628 | zrc->atime = jiffies; | |
629 | } | |
630 | ||
631 | /* | |
632 | * Start reclaim if necessary. | |
633 | */ | |
634 | void dmz_schedule_reclaim(struct dmz_reclaim *zrc) | |
635 | { | |
34f5affd HR |
636 | unsigned int p_unmap = dmz_reclaim_percentage(zrc); |
637 | ||
638 | if (dmz_should_reclaim(zrc, p_unmap)) | |
3b1a94c8 DLM |
639 | mod_delayed_work(zrc->wq, &zrc->work, 0); |
640 | } |