10fc479b1SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
288459642SOmar Sandoval /*
388459642SOmar Sandoval * Copyright (C) 2016 Facebook
488459642SOmar Sandoval * Copyright (C) 2013-2014 Jens Axboe
588459642SOmar Sandoval */
688459642SOmar Sandoval
7af8601adSIngo Molnar #include <linux/sched.h>
898d95416SOmar Sandoval #include <linux/random.h>
988459642SOmar Sandoval #include <linux/sbitmap.h>
1024af1ccfSOmar Sandoval #include <linux/seq_file.h>
1188459642SOmar Sandoval
init_alloc_hint(struct sbitmap * sb,gfp_t flags)12c548e62bSMing Lei static int init_alloc_hint(struct sbitmap *sb, gfp_t flags)
13bf2c4282SMing Lei {
14c548e62bSMing Lei unsigned depth = sb->depth;
15bf2c4282SMing Lei
16c548e62bSMing Lei sb->alloc_hint = alloc_percpu_gfp(unsigned int, flags);
17c548e62bSMing Lei if (!sb->alloc_hint)
18bf2c4282SMing Lei return -ENOMEM;
19bf2c4282SMing Lei
20c548e62bSMing Lei if (depth && !sb->round_robin) {
21bf2c4282SMing Lei int i;
22bf2c4282SMing Lei
23bf2c4282SMing Lei for_each_possible_cpu(i)
248032bf12SJason A. Donenfeld *per_cpu_ptr(sb->alloc_hint, i) = get_random_u32_below(depth);
25bf2c4282SMing Lei }
26bf2c4282SMing Lei return 0;
27bf2c4282SMing Lei }
28bf2c4282SMing Lei
update_alloc_hint_before_get(struct sbitmap * sb,unsigned int depth)29c548e62bSMing Lei static inline unsigned update_alloc_hint_before_get(struct sbitmap *sb,
30bf2c4282SMing Lei unsigned int depth)
31bf2c4282SMing Lei {
32bf2c4282SMing Lei unsigned hint;
33bf2c4282SMing Lei
34c548e62bSMing Lei hint = this_cpu_read(*sb->alloc_hint);
35bf2c4282SMing Lei if (unlikely(hint >= depth)) {
368032bf12SJason A. Donenfeld hint = depth ? get_random_u32_below(depth) : 0;
37c548e62bSMing Lei this_cpu_write(*sb->alloc_hint, hint);
38bf2c4282SMing Lei }
39bf2c4282SMing Lei
40bf2c4282SMing Lei return hint;
41bf2c4282SMing Lei }
42bf2c4282SMing Lei
update_alloc_hint_after_get(struct sbitmap * sb,unsigned int depth,unsigned int hint,unsigned int nr)43c548e62bSMing Lei static inline void update_alloc_hint_after_get(struct sbitmap *sb,
44bf2c4282SMing Lei unsigned int depth,
45bf2c4282SMing Lei unsigned int hint,
46bf2c4282SMing Lei unsigned int nr)
47bf2c4282SMing Lei {
48bf2c4282SMing Lei if (nr == -1) {
49bf2c4282SMing Lei /* If the map is full, a hint won't do us much good. */
50c548e62bSMing Lei this_cpu_write(*sb->alloc_hint, 0);
51c548e62bSMing Lei } else if (nr == hint || unlikely(sb->round_robin)) {
52bf2c4282SMing Lei /* Only update the hint if we used it. */
53bf2c4282SMing Lei hint = nr + 1;
54bf2c4282SMing Lei if (hint >= depth - 1)
55bf2c4282SMing Lei hint = 0;
56c548e62bSMing Lei this_cpu_write(*sb->alloc_hint, hint);
57bf2c4282SMing Lei }
58bf2c4282SMing Lei }
59bf2c4282SMing Lei
60b2dbff1bSJens Axboe /*
61b2dbff1bSJens Axboe * See if we have deferred clears that we can batch move
62b2dbff1bSJens Axboe */
sbitmap_deferred_clear(struct sbitmap_word * map)63b78beea0SPavel Begunkov static inline bool sbitmap_deferred_clear(struct sbitmap_word *map)
64b2dbff1bSJens Axboe {
65c3250c8dSPavel Begunkov unsigned long mask;
66b2dbff1bSJens Axboe
67661d4f55SPavel Begunkov if (!READ_ONCE(map->cleared))
68661d4f55SPavel Begunkov return false;
69b2dbff1bSJens Axboe
70b2dbff1bSJens Axboe /*
71b2dbff1bSJens Axboe * First get a stable cleared mask, setting the old mask to 0.
72b2dbff1bSJens Axboe */
73b78beea0SPavel Begunkov mask = xchg(&map->cleared, 0);
74b2dbff1bSJens Axboe
75b2dbff1bSJens Axboe /*
76b2dbff1bSJens Axboe * Now clear the masked bits in our free word
77b2dbff1bSJens Axboe */
78c3250c8dSPavel Begunkov atomic_long_andnot(mask, (atomic_long_t *)&map->word);
79c3250c8dSPavel Begunkov BUILD_BUG_ON(sizeof(atomic_long_t) != sizeof(map->word));
80661d4f55SPavel Begunkov return true;
81b2dbff1bSJens Axboe }
82b2dbff1bSJens Axboe
sbitmap_init_node(struct sbitmap * sb,unsigned int depth,int shift,gfp_t flags,int node,bool round_robin,bool alloc_hint)8388459642SOmar Sandoval int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift,
84c548e62bSMing Lei gfp_t flags, int node, bool round_robin,
85c548e62bSMing Lei bool alloc_hint)
8688459642SOmar Sandoval {
8788459642SOmar Sandoval unsigned int bits_per_word;
8888459642SOmar Sandoval
892d13b1eaSMing Lei if (shift < 0)
902d13b1eaSMing Lei shift = sbitmap_calculate_shift(depth);
912d13b1eaSMing Lei
9288459642SOmar Sandoval bits_per_word = 1U << shift;
9388459642SOmar Sandoval if (bits_per_word > BITS_PER_LONG)
9488459642SOmar Sandoval return -EINVAL;
9588459642SOmar Sandoval
9688459642SOmar Sandoval sb->shift = shift;
9788459642SOmar Sandoval sb->depth = depth;
9888459642SOmar Sandoval sb->map_nr = DIV_ROUND_UP(sb->depth, bits_per_word);
99efe1f3a1SMing Lei sb->round_robin = round_robin;
10088459642SOmar Sandoval
10188459642SOmar Sandoval if (depth == 0) {
10288459642SOmar Sandoval sb->map = NULL;
10388459642SOmar Sandoval return 0;
10488459642SOmar Sandoval }
10588459642SOmar Sandoval
106c548e62bSMing Lei if (alloc_hint) {
107c548e62bSMing Lei if (init_alloc_hint(sb, flags))
10888459642SOmar Sandoval return -ENOMEM;
109c548e62bSMing Lei } else {
110c548e62bSMing Lei sb->alloc_hint = NULL;
111c548e62bSMing Lei }
112c548e62bSMing Lei
113863a66cdSMing Lei sb->map = kvzalloc_node(sb->map_nr * sizeof(*sb->map), flags, node);
114c548e62bSMing Lei if (!sb->map) {
115c548e62bSMing Lei free_percpu(sb->alloc_hint);
116c548e62bSMing Lei return -ENOMEM;
117c548e62bSMing Lei }
11888459642SOmar Sandoval
11988459642SOmar Sandoval return 0;
12088459642SOmar Sandoval }
12188459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_init_node);
12288459642SOmar Sandoval
sbitmap_resize(struct sbitmap * sb,unsigned int depth)12388459642SOmar Sandoval void sbitmap_resize(struct sbitmap *sb, unsigned int depth)
12488459642SOmar Sandoval {
12588459642SOmar Sandoval unsigned int bits_per_word = 1U << sb->shift;
12688459642SOmar Sandoval unsigned int i;
12788459642SOmar Sandoval
128b2dbff1bSJens Axboe for (i = 0; i < sb->map_nr; i++)
129b78beea0SPavel Begunkov sbitmap_deferred_clear(&sb->map[i]);
130b2dbff1bSJens Axboe
13188459642SOmar Sandoval sb->depth = depth;
13288459642SOmar Sandoval sb->map_nr = DIV_ROUND_UP(sb->depth, bits_per_word);
13388459642SOmar Sandoval }
13488459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_resize);
13588459642SOmar Sandoval
__sbitmap_get_word(unsigned long * word,unsigned long depth,unsigned int hint,bool wrap)136c05e6673SOmar Sandoval static int __sbitmap_get_word(unsigned long *word, unsigned long depth,
137c05e6673SOmar Sandoval unsigned int hint, bool wrap)
13888459642SOmar Sandoval {
13988459642SOmar Sandoval int nr;
14088459642SOmar Sandoval
1410eff1f1aSPavel Begunkov /* don't wrap if starting from 0 */
1420eff1f1aSPavel Begunkov wrap = wrap && hint;
1430eff1f1aSPavel Begunkov
14488459642SOmar Sandoval while (1) {
145c05e6673SOmar Sandoval nr = find_next_zero_bit(word, depth, hint);
146c05e6673SOmar Sandoval if (unlikely(nr >= depth)) {
14788459642SOmar Sandoval /*
14888459642SOmar Sandoval * We started with an offset, and we didn't reset the
14988459642SOmar Sandoval * offset to 0 in a failure case, so start from 0 to
15088459642SOmar Sandoval * exhaust the map.
15188459642SOmar Sandoval */
1520eff1f1aSPavel Begunkov if (hint && wrap) {
1530eff1f1aSPavel Begunkov hint = 0;
15488459642SOmar Sandoval continue;
15588459642SOmar Sandoval }
15688459642SOmar Sandoval return -1;
15788459642SOmar Sandoval }
15888459642SOmar Sandoval
1594ace53f1SOmar Sandoval if (!test_and_set_bit_lock(nr, word))
16088459642SOmar Sandoval break;
16188459642SOmar Sandoval
16288459642SOmar Sandoval hint = nr + 1;
163c05e6673SOmar Sandoval if (hint >= depth - 1)
16488459642SOmar Sandoval hint = 0;
16588459642SOmar Sandoval }
16688459642SOmar Sandoval
16788459642SOmar Sandoval return nr;
16888459642SOmar Sandoval }
16988459642SOmar Sandoval
sbitmap_find_bit_in_word(struct sbitmap_word * map,unsigned int depth,unsigned int alloc_hint,bool wrap)17008470a98SKemeng Shi static int sbitmap_find_bit_in_word(struct sbitmap_word *map,
17108470a98SKemeng Shi unsigned int depth,
17208470a98SKemeng Shi unsigned int alloc_hint,
17308470a98SKemeng Shi bool wrap)
174ea86ea2cSJens Axboe {
175ea86ea2cSJens Axboe int nr;
176ea86ea2cSJens Axboe
177ea86ea2cSJens Axboe do {
17808470a98SKemeng Shi nr = __sbitmap_get_word(&map->word, depth,
17908470a98SKemeng Shi alloc_hint, wrap);
180ea86ea2cSJens Axboe if (nr != -1)
181ea86ea2cSJens Axboe break;
182b78beea0SPavel Begunkov if (!sbitmap_deferred_clear(map))
183ea86ea2cSJens Axboe break;
184ea86ea2cSJens Axboe } while (1);
185ea86ea2cSJens Axboe
186ea86ea2cSJens Axboe return nr;
187ea86ea2cSJens Axboe }
188ea86ea2cSJens Axboe
sbitmap_find_bit(struct sbitmap * sb,unsigned int depth,unsigned int index,unsigned int alloc_hint,bool wrap)189678418c6SKemeng Shi static int sbitmap_find_bit(struct sbitmap *sb,
190678418c6SKemeng Shi unsigned int depth,
191678418c6SKemeng Shi unsigned int index,
192678418c6SKemeng Shi unsigned int alloc_hint,
193678418c6SKemeng Shi bool wrap)
194678418c6SKemeng Shi {
195678418c6SKemeng Shi unsigned int i;
196678418c6SKemeng Shi int nr = -1;
197678418c6SKemeng Shi
198678418c6SKemeng Shi for (i = 0; i < sb->map_nr; i++) {
199678418c6SKemeng Shi nr = sbitmap_find_bit_in_word(&sb->map[index],
200678418c6SKemeng Shi min_t(unsigned int,
201678418c6SKemeng Shi __map_depth(sb, index),
202678418c6SKemeng Shi depth),
203678418c6SKemeng Shi alloc_hint, wrap);
204678418c6SKemeng Shi
205678418c6SKemeng Shi if (nr != -1) {
206678418c6SKemeng Shi nr += index << sb->shift;
207678418c6SKemeng Shi break;
208678418c6SKemeng Shi }
209678418c6SKemeng Shi
210678418c6SKemeng Shi /* Jump to next index. */
211678418c6SKemeng Shi alloc_hint = 0;
212678418c6SKemeng Shi if (++index >= sb->map_nr)
213678418c6SKemeng Shi index = 0;
214678418c6SKemeng Shi }
215678418c6SKemeng Shi
216678418c6SKemeng Shi return nr;
217678418c6SKemeng Shi }
218678418c6SKemeng Shi
__sbitmap_get(struct sbitmap * sb,unsigned int alloc_hint)219c548e62bSMing Lei static int __sbitmap_get(struct sbitmap *sb, unsigned int alloc_hint)
22088459642SOmar Sandoval {
221678418c6SKemeng Shi unsigned int index;
22288459642SOmar Sandoval
22388459642SOmar Sandoval index = SB_NR_TO_INDEX(sb, alloc_hint);
22488459642SOmar Sandoval
22527fae429SJens Axboe /*
22627fae429SJens Axboe * Unless we're doing round robin tag allocation, just use the
22727fae429SJens Axboe * alloc_hint to find the right word index. No point in looping
22827fae429SJens Axboe * twice in find_next_zero_bit() for that case.
22927fae429SJens Axboe */
230efe1f3a1SMing Lei if (sb->round_robin)
23127fae429SJens Axboe alloc_hint = SB_NR_TO_BIT(sb, alloc_hint);
23227fae429SJens Axboe else
23327fae429SJens Axboe alloc_hint = 0;
23427fae429SJens Axboe
235678418c6SKemeng Shi return sbitmap_find_bit(sb, UINT_MAX, index, alloc_hint,
236678418c6SKemeng Shi !sb->round_robin);
23788459642SOmar Sandoval }
238c548e62bSMing Lei
sbitmap_get(struct sbitmap * sb)239c548e62bSMing Lei int sbitmap_get(struct sbitmap *sb)
240c548e62bSMing Lei {
241c548e62bSMing Lei int nr;
242c548e62bSMing Lei unsigned int hint, depth;
243c548e62bSMing Lei
244c548e62bSMing Lei if (WARN_ON_ONCE(unlikely(!sb->alloc_hint)))
245c548e62bSMing Lei return -1;
246c548e62bSMing Lei
247c548e62bSMing Lei depth = READ_ONCE(sb->depth);
248c548e62bSMing Lei hint = update_alloc_hint_before_get(sb, depth);
249c548e62bSMing Lei nr = __sbitmap_get(sb, hint);
250c548e62bSMing Lei update_alloc_hint_after_get(sb, depth, hint, nr);
251c548e62bSMing Lei
252c548e62bSMing Lei return nr;
253c548e62bSMing Lei }
25488459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_get);
25588459642SOmar Sandoval
__sbitmap_get_shallow(struct sbitmap * sb,unsigned int alloc_hint,unsigned long shallow_depth)256c548e62bSMing Lei static int __sbitmap_get_shallow(struct sbitmap *sb,
257c548e62bSMing Lei unsigned int alloc_hint,
258c05e6673SOmar Sandoval unsigned long shallow_depth)
259c05e6673SOmar Sandoval {
260678418c6SKemeng Shi unsigned int index;
261c05e6673SOmar Sandoval
262c05e6673SOmar Sandoval index = SB_NR_TO_INDEX(sb, alloc_hint);
263f1591a8bSKemeng Shi alloc_hint = SB_NR_TO_BIT(sb, alloc_hint);
264c05e6673SOmar Sandoval
265678418c6SKemeng Shi return sbitmap_find_bit(sb, shallow_depth, index, alloc_hint, true);
266c05e6673SOmar Sandoval }
267c548e62bSMing Lei
sbitmap_get_shallow(struct sbitmap * sb,unsigned long shallow_depth)268c548e62bSMing Lei int sbitmap_get_shallow(struct sbitmap *sb, unsigned long shallow_depth)
269c548e62bSMing Lei {
270c548e62bSMing Lei int nr;
271c548e62bSMing Lei unsigned int hint, depth;
272c548e62bSMing Lei
273c548e62bSMing Lei if (WARN_ON_ONCE(unlikely(!sb->alloc_hint)))
274c548e62bSMing Lei return -1;
275c548e62bSMing Lei
276c548e62bSMing Lei depth = READ_ONCE(sb->depth);
277c548e62bSMing Lei hint = update_alloc_hint_before_get(sb, depth);
278c548e62bSMing Lei nr = __sbitmap_get_shallow(sb, hint, shallow_depth);
279c548e62bSMing Lei update_alloc_hint_after_get(sb, depth, hint, nr);
280c548e62bSMing Lei
281c548e62bSMing Lei return nr;
282c548e62bSMing Lei }
283c05e6673SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_get_shallow);
284c05e6673SOmar Sandoval
sbitmap_any_bit_set(const struct sbitmap * sb)28588459642SOmar Sandoval bool sbitmap_any_bit_set(const struct sbitmap *sb)
28688459642SOmar Sandoval {
28788459642SOmar Sandoval unsigned int i;
28888459642SOmar Sandoval
28988459642SOmar Sandoval for (i = 0; i < sb->map_nr; i++) {
290b2dbff1bSJens Axboe if (sb->map[i].word & ~sb->map[i].cleared)
29188459642SOmar Sandoval return true;
29288459642SOmar Sandoval }
29388459642SOmar Sandoval return false;
29488459642SOmar Sandoval }
29588459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
29688459642SOmar Sandoval
__sbitmap_weight(const struct sbitmap * sb,bool set)297ea86ea2cSJens Axboe static unsigned int __sbitmap_weight(const struct sbitmap *sb, bool set)
29888459642SOmar Sandoval {
29960658e0dSColin Ian King unsigned int i, weight = 0;
30088459642SOmar Sandoval
30188459642SOmar Sandoval for (i = 0; i < sb->map_nr; i++) {
30288459642SOmar Sandoval const struct sbitmap_word *word = &sb->map[i];
3033301bc53SMing Lei unsigned int word_depth = __map_depth(sb, i);
30488459642SOmar Sandoval
305ea86ea2cSJens Axboe if (set)
3063301bc53SMing Lei weight += bitmap_weight(&word->word, word_depth);
307ea86ea2cSJens Axboe else
3083301bc53SMing Lei weight += bitmap_weight(&word->cleared, word_depth);
30988459642SOmar Sandoval }
31088459642SOmar Sandoval return weight;
31188459642SOmar Sandoval }
312ea86ea2cSJens Axboe
sbitmap_cleared(const struct sbitmap * sb)313ea86ea2cSJens Axboe static unsigned int sbitmap_cleared(const struct sbitmap *sb)
314ea86ea2cSJens Axboe {
315ea86ea2cSJens Axboe return __sbitmap_weight(sb, false);
316ea86ea2cSJens Axboe }
31788459642SOmar Sandoval
sbitmap_weight(const struct sbitmap * sb)318cbb9950bSMing Lei unsigned int sbitmap_weight(const struct sbitmap *sb)
319cbb9950bSMing Lei {
320cbb9950bSMing Lei return __sbitmap_weight(sb, true) - sbitmap_cleared(sb);
321cbb9950bSMing Lei }
322cbb9950bSMing Lei EXPORT_SYMBOL_GPL(sbitmap_weight);
323cbb9950bSMing Lei
sbitmap_show(struct sbitmap * sb,struct seq_file * m)32424af1ccfSOmar Sandoval void sbitmap_show(struct sbitmap *sb, struct seq_file *m)
32524af1ccfSOmar Sandoval {
32624af1ccfSOmar Sandoval seq_printf(m, "depth=%u\n", sb->depth);
327cbb9950bSMing Lei seq_printf(m, "busy=%u\n", sbitmap_weight(sb));
328ea86ea2cSJens Axboe seq_printf(m, "cleared=%u\n", sbitmap_cleared(sb));
32924af1ccfSOmar Sandoval seq_printf(m, "bits_per_word=%u\n", 1U << sb->shift);
33024af1ccfSOmar Sandoval seq_printf(m, "map_nr=%u\n", sb->map_nr);
33124af1ccfSOmar Sandoval }
33224af1ccfSOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_show);
33324af1ccfSOmar Sandoval
emit_byte(struct seq_file * m,unsigned int offset,u8 byte)33424af1ccfSOmar Sandoval static inline void emit_byte(struct seq_file *m, unsigned int offset, u8 byte)
33524af1ccfSOmar Sandoval {
33624af1ccfSOmar Sandoval if ((offset & 0xf) == 0) {
33724af1ccfSOmar Sandoval if (offset != 0)
33824af1ccfSOmar Sandoval seq_putc(m, '\n');
33924af1ccfSOmar Sandoval seq_printf(m, "%08x:", offset);
34024af1ccfSOmar Sandoval }
34124af1ccfSOmar Sandoval if ((offset & 0x1) == 0)
34224af1ccfSOmar Sandoval seq_putc(m, ' ');
34324af1ccfSOmar Sandoval seq_printf(m, "%02x", byte);
34424af1ccfSOmar Sandoval }
34524af1ccfSOmar Sandoval
sbitmap_bitmap_show(struct sbitmap * sb,struct seq_file * m)34624af1ccfSOmar Sandoval void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m)
34724af1ccfSOmar Sandoval {
34824af1ccfSOmar Sandoval u8 byte = 0;
34924af1ccfSOmar Sandoval unsigned int byte_bits = 0;
35024af1ccfSOmar Sandoval unsigned int offset = 0;
35124af1ccfSOmar Sandoval int i;
35224af1ccfSOmar Sandoval
35324af1ccfSOmar Sandoval for (i = 0; i < sb->map_nr; i++) {
35424af1ccfSOmar Sandoval unsigned long word = READ_ONCE(sb->map[i].word);
3556bf0eb55SJohn Garry unsigned long cleared = READ_ONCE(sb->map[i].cleared);
3563301bc53SMing Lei unsigned int word_bits = __map_depth(sb, i);
35724af1ccfSOmar Sandoval
3586bf0eb55SJohn Garry word &= ~cleared;
3596bf0eb55SJohn Garry
36024af1ccfSOmar Sandoval while (word_bits > 0) {
36124af1ccfSOmar Sandoval unsigned int bits = min(8 - byte_bits, word_bits);
36224af1ccfSOmar Sandoval
36324af1ccfSOmar Sandoval byte |= (word & (BIT(bits) - 1)) << byte_bits;
36424af1ccfSOmar Sandoval byte_bits += bits;
36524af1ccfSOmar Sandoval if (byte_bits == 8) {
36624af1ccfSOmar Sandoval emit_byte(m, offset, byte);
36724af1ccfSOmar Sandoval byte = 0;
36824af1ccfSOmar Sandoval byte_bits = 0;
36924af1ccfSOmar Sandoval offset++;
37024af1ccfSOmar Sandoval }
37124af1ccfSOmar Sandoval word >>= bits;
37224af1ccfSOmar Sandoval word_bits -= bits;
37324af1ccfSOmar Sandoval }
37424af1ccfSOmar Sandoval }
37524af1ccfSOmar Sandoval if (byte_bits) {
37624af1ccfSOmar Sandoval emit_byte(m, offset, byte);
37724af1ccfSOmar Sandoval offset++;
37824af1ccfSOmar Sandoval }
37924af1ccfSOmar Sandoval if (offset)
38024af1ccfSOmar Sandoval seq_putc(m, '\n');
38124af1ccfSOmar Sandoval }
38224af1ccfSOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_bitmap_show);
38324af1ccfSOmar Sandoval
sbq_calc_wake_batch(struct sbitmap_queue * sbq,unsigned int depth)384a3275539SOmar Sandoval static unsigned int sbq_calc_wake_batch(struct sbitmap_queue *sbq,
385a3275539SOmar Sandoval unsigned int depth)
38688459642SOmar Sandoval {
38788459642SOmar Sandoval unsigned int wake_batch;
388a3275539SOmar Sandoval unsigned int shallow_depth;
38988459642SOmar Sandoval
39088459642SOmar Sandoval /*
39188459642SOmar Sandoval * For each batch, we wake up one queue. We need to make sure that our
392a3275539SOmar Sandoval * batch size is small enough that the full depth of the bitmap,
393a3275539SOmar Sandoval * potentially limited by a shallow depth, is enough to wake up all of
394a3275539SOmar Sandoval * the queues.
395a3275539SOmar Sandoval *
396a3275539SOmar Sandoval * Each full word of the bitmap has bits_per_word bits, and there might
397a3275539SOmar Sandoval * be a partial word. There are depth / bits_per_word full words and
398a3275539SOmar Sandoval * depth % bits_per_word bits left over. In bitwise arithmetic:
399a3275539SOmar Sandoval *
400a3275539SOmar Sandoval * bits_per_word = 1 << shift
401a3275539SOmar Sandoval * depth / bits_per_word = depth >> shift
402a3275539SOmar Sandoval * depth % bits_per_word = depth & ((1 << shift) - 1)
403a3275539SOmar Sandoval *
404a3275539SOmar Sandoval * Each word can be limited to sbq->min_shallow_depth bits.
40588459642SOmar Sandoval */
406a3275539SOmar Sandoval shallow_depth = min(1U << sbq->sb.shift, sbq->min_shallow_depth);
407a3275539SOmar Sandoval depth = ((depth >> sbq->sb.shift) * shallow_depth +
408a3275539SOmar Sandoval min(depth & ((1U << sbq->sb.shift) - 1), shallow_depth));
409a3275539SOmar Sandoval wake_batch = clamp_t(unsigned int, depth / SBQ_WAIT_QUEUES, 1,
410a3275539SOmar Sandoval SBQ_WAKE_BATCH);
41188459642SOmar Sandoval
41288459642SOmar Sandoval return wake_batch;
41388459642SOmar Sandoval }
41488459642SOmar Sandoval
sbitmap_queue_init_node(struct sbitmap_queue * sbq,unsigned int depth,int shift,bool round_robin,gfp_t flags,int node)41588459642SOmar Sandoval int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth,
416f4a644dbSOmar Sandoval int shift, bool round_robin, gfp_t flags, int node)
41788459642SOmar Sandoval {
41888459642SOmar Sandoval int ret;
41988459642SOmar Sandoval int i;
42088459642SOmar Sandoval
421efe1f3a1SMing Lei ret = sbitmap_init_node(&sbq->sb, depth, shift, flags, node,
422c548e62bSMing Lei round_robin, true);
42388459642SOmar Sandoval if (ret)
42488459642SOmar Sandoval return ret;
42588459642SOmar Sandoval
426a3275539SOmar Sandoval sbq->min_shallow_depth = UINT_MAX;
427a3275539SOmar Sandoval sbq->wake_batch = sbq_calc_wake_batch(sbq, depth);
42888459642SOmar Sandoval atomic_set(&sbq->wake_index, 0);
4295d2ee712SJens Axboe atomic_set(&sbq->ws_active, 0);
4304f8126bbSGabriel Krisman Bertazi atomic_set(&sbq->completion_cnt, 0);
4314f8126bbSGabriel Krisman Bertazi atomic_set(&sbq->wakeup_cnt, 0);
43288459642SOmar Sandoval
43348e28166SOmar Sandoval sbq->ws = kzalloc_node(SBQ_WAIT_QUEUES * sizeof(*sbq->ws), flags, node);
43488459642SOmar Sandoval if (!sbq->ws) {
43588459642SOmar Sandoval sbitmap_free(&sbq->sb);
43688459642SOmar Sandoval return -ENOMEM;
43788459642SOmar Sandoval }
43888459642SOmar Sandoval
4394f8126bbSGabriel Krisman Bertazi for (i = 0; i < SBQ_WAIT_QUEUES; i++)
44088459642SOmar Sandoval init_waitqueue_head(&sbq->ws[i].wait);
441f4a644dbSOmar Sandoval
44288459642SOmar Sandoval return 0;
44388459642SOmar Sandoval }
44488459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_queue_init_node);
44588459642SOmar Sandoval
sbitmap_queue_update_wake_batch(struct sbitmap_queue * sbq,unsigned int depth)446180dccb0SLaibin Qiu static void sbitmap_queue_update_wake_batch(struct sbitmap_queue *sbq,
447180dccb0SLaibin Qiu unsigned int depth)
448180dccb0SLaibin Qiu {
449180dccb0SLaibin Qiu unsigned int wake_batch;
450180dccb0SLaibin Qiu
451180dccb0SLaibin Qiu wake_batch = sbq_calc_wake_batch(sbq, depth);
4524f8126bbSGabriel Krisman Bertazi if (sbq->wake_batch != wake_batch)
4534f8126bbSGabriel Krisman Bertazi WRITE_ONCE(sbq->wake_batch, wake_batch);
454180dccb0SLaibin Qiu }
455180dccb0SLaibin Qiu
sbitmap_queue_recalculate_wake_batch(struct sbitmap_queue * sbq,unsigned int users)456180dccb0SLaibin Qiu void sbitmap_queue_recalculate_wake_batch(struct sbitmap_queue *sbq,
457180dccb0SLaibin Qiu unsigned int users)
458180dccb0SLaibin Qiu {
459180dccb0SLaibin Qiu unsigned int wake_batch;
46010825410SLaibin Qiu unsigned int depth = (sbq->sb.depth + users - 1) / users;
461180dccb0SLaibin Qiu
46210825410SLaibin Qiu wake_batch = clamp_val(depth / SBQ_WAIT_QUEUES,
463b5fcf787SKemeng Shi 1, SBQ_WAKE_BATCH);
4644f8126bbSGabriel Krisman Bertazi
4654f8126bbSGabriel Krisman Bertazi WRITE_ONCE(sbq->wake_batch, wake_batch);
466180dccb0SLaibin Qiu }
467180dccb0SLaibin Qiu EXPORT_SYMBOL_GPL(sbitmap_queue_recalculate_wake_batch);
468180dccb0SLaibin Qiu
sbitmap_queue_resize(struct sbitmap_queue * sbq,unsigned int depth)469a3275539SOmar Sandoval void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth)
470a3275539SOmar Sandoval {
471a3275539SOmar Sandoval sbitmap_queue_update_wake_batch(sbq, depth);
47288459642SOmar Sandoval sbitmap_resize(&sbq->sb, depth);
47388459642SOmar Sandoval }
47488459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_queue_resize);
47588459642SOmar Sandoval
__sbitmap_queue_get(struct sbitmap_queue * sbq)476f4a644dbSOmar Sandoval int __sbitmap_queue_get(struct sbitmap_queue *sbq)
47740aabb67SOmar Sandoval {
478c548e62bSMing Lei return sbitmap_get(&sbq->sb);
47940aabb67SOmar Sandoval }
48040aabb67SOmar Sandoval EXPORT_SYMBOL_GPL(__sbitmap_queue_get);
48140aabb67SOmar Sandoval
__sbitmap_queue_get_batch(struct sbitmap_queue * sbq,int nr_tags,unsigned int * offset)4829672b0d4SJens Axboe unsigned long __sbitmap_queue_get_batch(struct sbitmap_queue *sbq, int nr_tags,
4839672b0d4SJens Axboe unsigned int *offset)
4849672b0d4SJens Axboe {
4859672b0d4SJens Axboe struct sbitmap *sb = &sbq->sb;
4869672b0d4SJens Axboe unsigned int hint, depth;
4879672b0d4SJens Axboe unsigned long index, nr;
4889672b0d4SJens Axboe int i;
4899672b0d4SJens Axboe
4909672b0d4SJens Axboe if (unlikely(sb->round_robin))
4919672b0d4SJens Axboe return 0;
4929672b0d4SJens Axboe
4939672b0d4SJens Axboe depth = READ_ONCE(sb->depth);
4949672b0d4SJens Axboe hint = update_alloc_hint_before_get(sb, depth);
4959672b0d4SJens Axboe
4969672b0d4SJens Axboe index = SB_NR_TO_INDEX(sb, hint);
4979672b0d4SJens Axboe
4989672b0d4SJens Axboe for (i = 0; i < sb->map_nr; i++) {
4999672b0d4SJens Axboe struct sbitmap_word *map = &sb->map[index];
5009672b0d4SJens Axboe unsigned long get_mask;
5013301bc53SMing Lei unsigned int map_depth = __map_depth(sb, index);
5029672b0d4SJens Axboe
5039672b0d4SJens Axboe sbitmap_deferred_clear(map);
5043301bc53SMing Lei if (map->word == (1UL << (map_depth - 1)) - 1)
505fbb564a5Swuchi goto next;
5069672b0d4SJens Axboe
5073301bc53SMing Lei nr = find_first_zero_bit(&map->word, map_depth);
5083301bc53SMing Lei if (nr + nr_tags <= map_depth) {
5099672b0d4SJens Axboe atomic_long_t *ptr = (atomic_long_t *) &map->word;
510c35227d4SUros Bizjak unsigned long val;
5119672b0d4SJens Axboe
512ddbfc34fSLiu Song get_mask = ((1UL << nr_tags) - 1) << nr;
5139672b0d4SJens Axboe val = READ_ONCE(map->word);
514903e86f3SKemeng Shi while (!atomic_long_try_cmpxchg(ptr, &val,
515903e86f3SKemeng Shi get_mask | val))
516903e86f3SKemeng Shi ;
517c35227d4SUros Bizjak get_mask = (get_mask & ~val) >> nr;
5189672b0d4SJens Axboe if (get_mask) {
5199672b0d4SJens Axboe *offset = nr + (index << sb->shift);
5209672b0d4SJens Axboe update_alloc_hint_after_get(sb, depth, hint,
521ddbfc34fSLiu Song *offset + nr_tags - 1);
5229672b0d4SJens Axboe return get_mask;
5239672b0d4SJens Axboe }
5249672b0d4SJens Axboe }
525fbb564a5Swuchi next:
5269672b0d4SJens Axboe /* Jump to next index. */
5279672b0d4SJens Axboe if (++index >= sb->map_nr)
5289672b0d4SJens Axboe index = 0;
5299672b0d4SJens Axboe }
5309672b0d4SJens Axboe
5319672b0d4SJens Axboe return 0;
5329672b0d4SJens Axboe }
5339672b0d4SJens Axboe
sbitmap_queue_get_shallow(struct sbitmap_queue * sbq,unsigned int shallow_depth)5343f607293SJohn Garry int sbitmap_queue_get_shallow(struct sbitmap_queue *sbq,
535c05e6673SOmar Sandoval unsigned int shallow_depth)
536c05e6673SOmar Sandoval {
53761445b56SOmar Sandoval WARN_ON_ONCE(shallow_depth < sbq->min_shallow_depth);
53861445b56SOmar Sandoval
539c548e62bSMing Lei return sbitmap_get_shallow(&sbq->sb, shallow_depth);
540c05e6673SOmar Sandoval }
5413f607293SJohn Garry EXPORT_SYMBOL_GPL(sbitmap_queue_get_shallow);
542c05e6673SOmar Sandoval
sbitmap_queue_min_shallow_depth(struct sbitmap_queue * sbq,unsigned int min_shallow_depth)543a3275539SOmar Sandoval void sbitmap_queue_min_shallow_depth(struct sbitmap_queue *sbq,
544a3275539SOmar Sandoval unsigned int min_shallow_depth)
545a3275539SOmar Sandoval {
546a3275539SOmar Sandoval sbq->min_shallow_depth = min_shallow_depth;
547a3275539SOmar Sandoval sbitmap_queue_update_wake_batch(sbq, sbq->sb.depth);
548a3275539SOmar Sandoval }
549a3275539SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_queue_min_shallow_depth);
550a3275539SOmar Sandoval
__sbitmap_queue_wake_up(struct sbitmap_queue * sbq,int nr)55126edb30dSGabriel Krisman Bertazi static void __sbitmap_queue_wake_up(struct sbitmap_queue *sbq, int nr)
55288459642SOmar Sandoval {
553*10639737SDavid Jeffery int i, wake_index, woken;
55488459642SOmar Sandoval
5555d2ee712SJens Axboe if (!atomic_read(&sbq->ws_active))
55626edb30dSGabriel Krisman Bertazi return;
5575d2ee712SJens Axboe
55888459642SOmar Sandoval wake_index = atomic_read(&sbq->wake_index);
55988459642SOmar Sandoval for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
56088459642SOmar Sandoval struct sbq_wait_state *ws = &sbq->ws[wake_index];
56188459642SOmar Sandoval
562976570b4SGabriel Krisman Bertazi /*
563976570b4SGabriel Krisman Bertazi * Advance the index before checking the current queue.
564976570b4SGabriel Krisman Bertazi * It improves fairness, by ensuring the queue doesn't
565976570b4SGabriel Krisman Bertazi * need to be fully emptied before trying to wake up
566976570b4SGabriel Krisman Bertazi * from the next one.
567976570b4SGabriel Krisman Bertazi */
568976570b4SGabriel Krisman Bertazi wake_index = sbq_index_inc(wake_index);
569976570b4SGabriel Krisman Bertazi
570*10639737SDavid Jeffery if (waitqueue_active(&ws->wait)) {
571*10639737SDavid Jeffery woken = wake_up_nr(&ws->wait, nr);
572*10639737SDavid Jeffery if (woken == nr)
57326edb30dSGabriel Krisman Bertazi break;
574*10639737SDavid Jeffery nr -= woken;
575*10639737SDavid Jeffery }
57688459642SOmar Sandoval }
57788459642SOmar Sandoval
57888459642SOmar Sandoval if (wake_index != atomic_read(&sbq->wake_index))
57988459642SOmar Sandoval atomic_set(&sbq->wake_index, wake_index);
580c854ab57SJens Axboe }
581c854ab57SJens Axboe
sbitmap_queue_wake_up(struct sbitmap_queue * sbq,int nr)5824acb8341SKeith Busch void sbitmap_queue_wake_up(struct sbitmap_queue *sbq, int nr)
583c854ab57SJens Axboe {
5844f8126bbSGabriel Krisman Bertazi unsigned int wake_batch = READ_ONCE(sbq->wake_batch);
5854f8126bbSGabriel Krisman Bertazi unsigned int wakeups;
5864f8126bbSGabriel Krisman Bertazi
5874f8126bbSGabriel Krisman Bertazi if (!atomic_read(&sbq->ws_active))
5884f8126bbSGabriel Krisman Bertazi return;
5894f8126bbSGabriel Krisman Bertazi
5904f8126bbSGabriel Krisman Bertazi atomic_add(nr, &sbq->completion_cnt);
5914f8126bbSGabriel Krisman Bertazi wakeups = atomic_read(&sbq->wakeup_cnt);
5924f8126bbSGabriel Krisman Bertazi
5934f8126bbSGabriel Krisman Bertazi do {
5944f8126bbSGabriel Krisman Bertazi if (atomic_read(&sbq->completion_cnt) - wakeups < wake_batch)
5954f8126bbSGabriel Krisman Bertazi return;
5964f8126bbSGabriel Krisman Bertazi } while (!atomic_try_cmpxchg(&sbq->wakeup_cnt,
5974f8126bbSGabriel Krisman Bertazi &wakeups, wakeups + wake_batch));
5984f8126bbSGabriel Krisman Bertazi
59926edb30dSGabriel Krisman Bertazi __sbitmap_queue_wake_up(sbq, wake_batch);
60088459642SOmar Sandoval }
601bce1b56cSJens Axboe EXPORT_SYMBOL_GPL(sbitmap_queue_wake_up);
60288459642SOmar Sandoval
sbitmap_update_cpu_hint(struct sbitmap * sb,int cpu,int tag)6031aec5e4aSJens Axboe static inline void sbitmap_update_cpu_hint(struct sbitmap *sb, int cpu, int tag)
6041aec5e4aSJens Axboe {
6051aec5e4aSJens Axboe if (likely(!sb->round_robin && tag < sb->depth))
6069f8b93a7SJens Axboe data_race(*per_cpu_ptr(sb->alloc_hint, cpu) = tag);
6071aec5e4aSJens Axboe }
6081aec5e4aSJens Axboe
sbitmap_queue_clear_batch(struct sbitmap_queue * sbq,int offset,int * tags,int nr_tags)6091aec5e4aSJens Axboe void sbitmap_queue_clear_batch(struct sbitmap_queue *sbq, int offset,
6101aec5e4aSJens Axboe int *tags, int nr_tags)
6111aec5e4aSJens Axboe {
6121aec5e4aSJens Axboe struct sbitmap *sb = &sbq->sb;
6131aec5e4aSJens Axboe unsigned long *addr = NULL;
6141aec5e4aSJens Axboe unsigned long mask = 0;
6151aec5e4aSJens Axboe int i;
6161aec5e4aSJens Axboe
6171aec5e4aSJens Axboe smp_mb__before_atomic();
6181aec5e4aSJens Axboe for (i = 0; i < nr_tags; i++) {
6191aec5e4aSJens Axboe const int tag = tags[i] - offset;
6201aec5e4aSJens Axboe unsigned long *this_addr;
6211aec5e4aSJens Axboe
6221aec5e4aSJens Axboe /* since we're clearing a batch, skip the deferred map */
6231aec5e4aSJens Axboe this_addr = &sb->map[SB_NR_TO_INDEX(sb, tag)].word;
6241aec5e4aSJens Axboe if (!addr) {
6251aec5e4aSJens Axboe addr = this_addr;
6261aec5e4aSJens Axboe } else if (addr != this_addr) {
6271aec5e4aSJens Axboe atomic_long_andnot(mask, (atomic_long_t *) addr);
6281aec5e4aSJens Axboe mask = 0;
6291aec5e4aSJens Axboe addr = this_addr;
6301aec5e4aSJens Axboe }
6311aec5e4aSJens Axboe mask |= (1UL << SB_NR_TO_BIT(sb, tag));
6321aec5e4aSJens Axboe }
6331aec5e4aSJens Axboe
6341aec5e4aSJens Axboe if (mask)
6351aec5e4aSJens Axboe atomic_long_andnot(mask, (atomic_long_t *) addr);
6361aec5e4aSJens Axboe
6371aec5e4aSJens Axboe smp_mb__after_atomic();
6384acb8341SKeith Busch sbitmap_queue_wake_up(sbq, nr_tags);
6391aec5e4aSJens Axboe sbitmap_update_cpu_hint(&sbq->sb, raw_smp_processor_id(),
6401aec5e4aSJens Axboe tags[nr_tags - 1] - offset);
6411aec5e4aSJens Axboe }
6421aec5e4aSJens Axboe
sbitmap_queue_clear(struct sbitmap_queue * sbq,unsigned int nr,unsigned int cpu)64340aabb67SOmar Sandoval void sbitmap_queue_clear(struct sbitmap_queue *sbq, unsigned int nr,
644f4a644dbSOmar Sandoval unsigned int cpu)
64588459642SOmar Sandoval {
646e6d1fa58SMing Lei /*
647e6d1fa58SMing Lei * Once the clear bit is set, the bit may be allocated out.
648e6d1fa58SMing Lei *
6499dbbc3b9SZhen Lei * Orders READ/WRITE on the associated instance(such as request
650e6d1fa58SMing Lei * of blk_mq) by this bit for avoiding race with re-allocation,
651e6d1fa58SMing Lei * and its pair is the memory barrier implied in __sbitmap_get_word.
652e6d1fa58SMing Lei *
653e6d1fa58SMing Lei * One invariant is that the clear bit has to be zero when the bit
654e6d1fa58SMing Lei * is in use.
655e6d1fa58SMing Lei */
656e6d1fa58SMing Lei smp_mb__before_atomic();
657ea86ea2cSJens Axboe sbitmap_deferred_clear_bit(&sbq->sb, nr);
658ea86ea2cSJens Axboe
659e6fc4649SMing Lei /*
660e6fc4649SMing Lei * Pairs with the memory barrier in set_current_state() to ensure the
661e6fc4649SMing Lei * proper ordering of clear_bit_unlock()/waitqueue_active() in the waker
662e6fc4649SMing Lei * and test_and_set_bit_lock()/prepare_to_wait()/finish_wait() in the
663e6fc4649SMing Lei * waiter. See the comment on waitqueue_active().
664e6fc4649SMing Lei */
665e6fc4649SMing Lei smp_mb__after_atomic();
6664acb8341SKeith Busch sbitmap_queue_wake_up(sbq, 1);
6671aec5e4aSJens Axboe sbitmap_update_cpu_hint(&sbq->sb, cpu, nr);
66888459642SOmar Sandoval }
66988459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_queue_clear);
67088459642SOmar Sandoval
sbitmap_queue_wake_all(struct sbitmap_queue * sbq)67188459642SOmar Sandoval void sbitmap_queue_wake_all(struct sbitmap_queue *sbq)
67288459642SOmar Sandoval {
67388459642SOmar Sandoval int i, wake_index;
67488459642SOmar Sandoval
67588459642SOmar Sandoval /*
676f66227deSOmar Sandoval * Pairs with the memory barrier in set_current_state() like in
677e6fc4649SMing Lei * sbitmap_queue_wake_up().
67888459642SOmar Sandoval */
67988459642SOmar Sandoval smp_mb();
68088459642SOmar Sandoval wake_index = atomic_read(&sbq->wake_index);
68188459642SOmar Sandoval for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
68288459642SOmar Sandoval struct sbq_wait_state *ws = &sbq->ws[wake_index];
68388459642SOmar Sandoval
68488459642SOmar Sandoval if (waitqueue_active(&ws->wait))
68588459642SOmar Sandoval wake_up(&ws->wait);
68688459642SOmar Sandoval
68788459642SOmar Sandoval wake_index = sbq_index_inc(wake_index);
68888459642SOmar Sandoval }
68988459642SOmar Sandoval }
69088459642SOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_queue_wake_all);
69124af1ccfSOmar Sandoval
sbitmap_queue_show(struct sbitmap_queue * sbq,struct seq_file * m)69224af1ccfSOmar Sandoval void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m)
69324af1ccfSOmar Sandoval {
69424af1ccfSOmar Sandoval bool first;
69524af1ccfSOmar Sandoval int i;
69624af1ccfSOmar Sandoval
69724af1ccfSOmar Sandoval sbitmap_show(&sbq->sb, m);
69824af1ccfSOmar Sandoval
69924af1ccfSOmar Sandoval seq_puts(m, "alloc_hint={");
70024af1ccfSOmar Sandoval first = true;
70124af1ccfSOmar Sandoval for_each_possible_cpu(i) {
70224af1ccfSOmar Sandoval if (!first)
70324af1ccfSOmar Sandoval seq_puts(m, ", ");
70424af1ccfSOmar Sandoval first = false;
705c548e62bSMing Lei seq_printf(m, "%u", *per_cpu_ptr(sbq->sb.alloc_hint, i));
70624af1ccfSOmar Sandoval }
70724af1ccfSOmar Sandoval seq_puts(m, "}\n");
70824af1ccfSOmar Sandoval
70924af1ccfSOmar Sandoval seq_printf(m, "wake_batch=%u\n", sbq->wake_batch);
71024af1ccfSOmar Sandoval seq_printf(m, "wake_index=%d\n", atomic_read(&sbq->wake_index));
7115d2ee712SJens Axboe seq_printf(m, "ws_active=%d\n", atomic_read(&sbq->ws_active));
71224af1ccfSOmar Sandoval
71324af1ccfSOmar Sandoval seq_puts(m, "ws={\n");
71424af1ccfSOmar Sandoval for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
71524af1ccfSOmar Sandoval struct sbq_wait_state *ws = &sbq->ws[i];
7164f8126bbSGabriel Krisman Bertazi seq_printf(m, "\t{.wait=%s},\n",
71724af1ccfSOmar Sandoval waitqueue_active(&ws->wait) ? "active" : "inactive");
71824af1ccfSOmar Sandoval }
71924af1ccfSOmar Sandoval seq_puts(m, "}\n");
72024af1ccfSOmar Sandoval
721efe1f3a1SMing Lei seq_printf(m, "round_robin=%d\n", sbq->sb.round_robin);
722a3275539SOmar Sandoval seq_printf(m, "min_shallow_depth=%u\n", sbq->min_shallow_depth);
72324af1ccfSOmar Sandoval }
72424af1ccfSOmar Sandoval EXPORT_SYMBOL_GPL(sbitmap_queue_show);
7255d2ee712SJens Axboe
sbitmap_add_wait_queue(struct sbitmap_queue * sbq,struct sbq_wait_state * ws,struct sbq_wait * sbq_wait)7269f6b7ef6SJens Axboe void sbitmap_add_wait_queue(struct sbitmap_queue *sbq,
7279f6b7ef6SJens Axboe struct sbq_wait_state *ws,
7289f6b7ef6SJens Axboe struct sbq_wait *sbq_wait)
7299f6b7ef6SJens Axboe {
7309f6b7ef6SJens Axboe if (!sbq_wait->sbq) {
7319f6b7ef6SJens Axboe sbq_wait->sbq = sbq;
7329f6b7ef6SJens Axboe atomic_inc(&sbq->ws_active);
7339f6b7ef6SJens Axboe add_wait_queue(&ws->wait, &sbq_wait->wait);
7349f6b7ef6SJens Axboe }
735df034c93SDavid Jeffery }
7369f6b7ef6SJens Axboe EXPORT_SYMBOL_GPL(sbitmap_add_wait_queue);
7379f6b7ef6SJens Axboe
sbitmap_del_wait_queue(struct sbq_wait * sbq_wait)7389f6b7ef6SJens Axboe void sbitmap_del_wait_queue(struct sbq_wait *sbq_wait)
7399f6b7ef6SJens Axboe {
7409f6b7ef6SJens Axboe list_del_init(&sbq_wait->wait.entry);
7419f6b7ef6SJens Axboe if (sbq_wait->sbq) {
7429f6b7ef6SJens Axboe atomic_dec(&sbq_wait->sbq->ws_active);
7439f6b7ef6SJens Axboe sbq_wait->sbq = NULL;
7449f6b7ef6SJens Axboe }
7459f6b7ef6SJens Axboe }
7469f6b7ef6SJens Axboe EXPORT_SYMBOL_GPL(sbitmap_del_wait_queue);
7479f6b7ef6SJens Axboe
sbitmap_prepare_to_wait(struct sbitmap_queue * sbq,struct sbq_wait_state * ws,struct sbq_wait * sbq_wait,int state)7485d2ee712SJens Axboe void sbitmap_prepare_to_wait(struct sbitmap_queue *sbq,
7495d2ee712SJens Axboe struct sbq_wait_state *ws,
7505d2ee712SJens Axboe struct sbq_wait *sbq_wait, int state)
7515d2ee712SJens Axboe {
7529f6b7ef6SJens Axboe if (!sbq_wait->sbq) {
7535d2ee712SJens Axboe atomic_inc(&sbq->ws_active);
7549f6b7ef6SJens Axboe sbq_wait->sbq = sbq;
7555d2ee712SJens Axboe }
7565d2ee712SJens Axboe prepare_to_wait_exclusive(&ws->wait, &sbq_wait->wait, state);
7575d2ee712SJens Axboe }
7585d2ee712SJens Axboe EXPORT_SYMBOL_GPL(sbitmap_prepare_to_wait);
7595d2ee712SJens Axboe
sbitmap_finish_wait(struct sbitmap_queue * sbq,struct sbq_wait_state * ws,struct sbq_wait * sbq_wait)7605d2ee712SJens Axboe void sbitmap_finish_wait(struct sbitmap_queue *sbq, struct sbq_wait_state *ws,
7615d2ee712SJens Axboe struct sbq_wait *sbq_wait)
7625d2ee712SJens Axboe {
7635d2ee712SJens Axboe finish_wait(&ws->wait, &sbq_wait->wait);
7649f6b7ef6SJens Axboe if (sbq_wait->sbq) {
7655d2ee712SJens Axboe atomic_dec(&sbq->ws_active);
7669f6b7ef6SJens Axboe sbq_wait->sbq = NULL;
7675d2ee712SJens Axboe }
7685d2ee712SJens Axboe }
7695d2ee712SJens Axboe EXPORT_SYMBOL_GPL(sbitmap_finish_wait);
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