| 1 |
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| 2 |
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| 3 | #ifndef _BCACHE_UTIL_H
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| 4 | #define _BCACHE_UTIL_H
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| 5 |
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| 6 | #include <linux/blkdev.h>
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| 7 | #include <linux/closure.h>
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| 8 | #include <linux/errno.h>
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| 9 | #include <linux/kernel.h>
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| 10 | #include <linux/sched/clock.h>
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| 11 | #include <linux/llist.h>
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| 12 | #include <linux/ratelimit.h>
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| 13 | #include <linux/vmalloc.h>
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| 14 | #include <linux/workqueue.h>
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| 15 | #include <linux/crc64.h>
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| 16 |
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| 17 | struct closure;
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| 18 |
|
| 19 | #ifdef CONFIG_BCACHE_DEBUG
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| 20 |
|
| 21 | #define EBUG_ON(cond) BUG_ON(cond)
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| 22 | #define atomic_dec_bug(v) BUG_ON(atomic_dec_return(v) < 0)
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| 23 | #define atomic_inc_bug(v, i) BUG_ON(atomic_inc_return(v) <= i)
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| 24 |
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| 25 | #else
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| 26 |
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| 27 | #define EBUG_ON(cond) do { if (cond) do {} while (0); } while (0)
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| 28 | #define atomic_dec_bug(v) atomic_dec(v)
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| 29 | #define atomic_inc_bug(v, i) atomic_inc(v)
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| 30 |
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| 31 | #endif
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| 32 |
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| 33 | #define DECLARE_HEAP(type, name) \
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| 34 | struct { \
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| 35 | size_t size, used; \
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| 36 | type *data; \
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| 37 | } name
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| 38 |
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| 39 | #define init_heap(heap, _size, gfp) \
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| 40 | ({ \
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| 41 | size_t _bytes; \
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| 42 | (heap)->used = 0; \
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| 43 | (heap)->size = (_size); \
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| 44 | _bytes = (heap)->size * sizeof(*(heap)->data); \
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| 45 | (heap)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL); \
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| 46 | (heap)->data; \
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| 47 | })
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| 48 |
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| 49 | #define free_heap(heap) \
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| 50 | do { \
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| 51 | kvfree((heap)->data); \
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| 52 | (heap)->data = NULL; \
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| 53 | } while (0)
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| 54 |
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| 55 | #define heap_swap(h, i, j) swap((h)->data[i], (h)->data[j])
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| 56 |
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| 57 | #define heap_sift(h, i, cmp) \
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| 58 | do { \
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| 59 | size_t _r, _j = i; \
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| 60 | \
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| 61 | for (; _j * 2 + 1 < (h)->used; _j = _r) { \
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| 62 | _r = _j * 2 + 1; \
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| 63 | if (_r + 1 < (h)->used && \
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| 64 | cmp((h)->data[_r], (h)->data[_r + 1])) \
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| 65 | _r++; \
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| 66 | \
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| 67 | if (cmp((h)->data[_r], (h)->data[_j])) \
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| 68 | break; \
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| 69 | heap_swap(h, _r, _j); \
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| 70 | } \
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| 71 | } while (0)
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| 72 |
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| 73 | #define heap_sift_down(h, i, cmp) \
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| 74 | do { \
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| 75 | while (i) { \
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| 76 | size_t p = (i - 1) / 2; \
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| 77 | if (cmp((h)->data[i], (h)->data[p])) \
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| 78 | break; \
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| 79 | heap_swap(h, i, p); \
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| 80 | i = p; \
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| 81 | } \
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| 82 | } while (0)
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| 83 |
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| 84 | #define heap_add(h, d, cmp) \
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| 85 | ({ \
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| 86 | bool _r = !heap_full(h); \
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| 87 | if (_r) { \
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| 88 | size_t _i = (h)->used++; \
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| 89 | (h)->data[_i] = d; \
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| 90 | \
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| 91 | heap_sift_down(h, _i, cmp); \
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| 92 | heap_sift(h, _i, cmp); \
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| 93 | } \
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| 94 | _r; \
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| 95 | })
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| 96 |
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| 97 | #define heap_pop(h, d, cmp) \
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| 98 | ({ \
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| 99 | bool _r = (h)->used; \
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| 100 | if (_r) { \
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| 101 | (d) = (h)->data[0]; \
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| 102 | (h)->used--; \
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| 103 | heap_swap(h, 0, (h)->used); \
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| 104 | heap_sift(h, 0, cmp); \
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| 105 | } \
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| 106 | _r; \
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| 107 | })
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| 108 |
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| 109 | #define heap_peek(h) ((h)->used ? (h)->data[0] : NULL)
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| 110 |
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| 111 | #define heap_full(h) ((h)->used == (h)->size)
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| 112 |
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| 113 | #define DECLARE_FIFO(type, name) \
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| 114 | struct { \
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| 115 | size_t front, back, size, mask; \
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| 116 | type *data; \
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| 117 | } name
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| 118 |
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| 119 | #define fifo_for_each(c, fifo, iter) \
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| 120 | for (iter = (fifo)->front; \
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| 121 | c = (fifo)->data[iter], iter != (fifo)->back; \
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| 122 | iter = (iter + 1) & (fifo)->mask)
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| 123 |
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| 124 | #define __init_fifo(fifo, gfp) \
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| 125 | ({ \
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| 126 | size_t _allocated_size, _bytes; \
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| 127 | BUG_ON(!(fifo)->size); \
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| 128 | \
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| 129 | _allocated_size = roundup_pow_of_two((fifo)->size + 1); \
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| 130 | _bytes = _allocated_size * sizeof(*(fifo)->data); \
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| 131 | \
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| 132 | (fifo)->mask = _allocated_size - 1; \
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| 133 | (fifo)->front = (fifo)->back = 0; \
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| 134 | \
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| 135 | (fifo)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL); \
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| 136 | (fifo)->data; \
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| 137 | })
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| 138 |
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| 139 | #define init_fifo_exact(fifo, _size, gfp) \
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| 140 | ({ \
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| 141 | (fifo)->size = (_size); \
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| 142 | __init_fifo(fifo, gfp); \
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| 143 | })
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| 144 |
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| 145 | #define init_fifo(fifo, _size, gfp) \
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| 146 | ({ \
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| 147 | (fifo)->size = (_size); \
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| 148 | if ((fifo)->size > 4) \
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| 149 | (fifo)->size = roundup_pow_of_two((fifo)->size) - 1; \
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| 150 | __init_fifo(fifo, gfp); \
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| 151 | })
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| 152 |
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| 153 | #define free_fifo(fifo) \
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| 154 | do { \
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| 155 | kvfree((fifo)->data); \
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| 156 | (fifo)->data = NULL; \
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| 157 | } while (0)
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| 158 |
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| 159 | #define fifo_used(fifo) (((fifo)->back - (fifo)->front) & (fifo)->mask)
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| 160 | #define fifo_free(fifo) ((fifo)->size - fifo_used(fifo))
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| 161 |
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| 162 | #define fifo_empty(fifo) (!fifo_used(fifo))
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| 163 | #define fifo_full(fifo) (!fifo_free(fifo))
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| 164 |
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| 165 | #define fifo_front(fifo) ((fifo)->data[(fifo)->front])
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| 166 | #define fifo_back(fifo) \
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| 167 | ((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
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| 168 |
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| 169 | #define fifo_idx(fifo, p) (((p) - &fifo_front(fifo)) & (fifo)->mask)
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| 170 |
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| 171 | #define fifo_push_back(fifo, i) \
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| 172 | ({ \
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| 173 | bool _r = !fifo_full((fifo)); \
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| 174 | if (_r) { \
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| 175 | (fifo)->data[(fifo)->back++] = (i); \
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| 176 | (fifo)->back &= (fifo)->mask; \
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| 177 | } \
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| 178 | _r; \
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| 179 | })
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| 180 |
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| 181 | #define fifo_pop_front(fifo, i) \
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| 182 | ({ \
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| 183 | bool _r = !fifo_empty((fifo)); \
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| 184 | if (_r) { \
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| 185 | (i) = (fifo)->data[(fifo)->front++]; \
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| 186 | (fifo)->front &= (fifo)->mask; \
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| 187 | } \
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| 188 | _r; \
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| 189 | })
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| 190 |
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| 191 | #define fifo_push_front(fifo, i) \
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| 192 | ({ \
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| 193 | bool _r = !fifo_full((fifo)); \
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| 194 | if (_r) { \
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| 195 | --(fifo)->front; \
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| 196 | (fifo)->front &= (fifo)->mask; \
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| 197 | (fifo)->data[(fifo)->front] = (i); \
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| 198 | } \
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| 199 | _r; \
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| 200 | })
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| 201 |
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| 202 | #define fifo_pop_back(fifo, i) \
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| 203 | ({ \
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| 204 | bool _r = !fifo_empty((fifo)); \
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| 205 | if (_r) { \
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| 206 | --(fifo)->back; \
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| 207 | (fifo)->back &= (fifo)->mask; \
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| 208 | (i) = (fifo)->data[(fifo)->back] \
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| 209 | } \
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| 210 | _r; \
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| 211 | })
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| 212 |
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| 213 | #define fifo_push(fifo, i) fifo_push_back(fifo, (i))
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| 214 | #define fifo_pop(fifo, i) fifo_pop_front(fifo, (i))
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| 215 |
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| 216 | #define fifo_swap(l, r) \
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| 217 | do { \
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| 218 | swap((l)->front, (r)->front); \
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| 219 | swap((l)->back, (r)->back); \
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| 220 | swap((l)->size, (r)->size); \
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| 221 | swap((l)->mask, (r)->mask); \
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| 222 | swap((l)->data, (r)->data); \
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| 223 | } while (0)
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| 224 |
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| 225 | #define fifo_move(dest, src) \
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| 226 | do { \
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| 227 | typeof(*((dest)->data)) _t; \
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| 228 | while (!fifo_full(dest) && \
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| 229 | fifo_pop(src, _t)) \
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| 230 | fifo_push(dest, _t); \
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| 231 | } while (0)
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| 232 |
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| 233 | |
| 234 | * Simple array based allocator - preallocates a number of elements and you can
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| 235 | * never allocate more than that, also has no locking.
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| 236 | *
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| 237 | * Handy because if you know you only need a fixed number of elements you don't
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| 238 | * have to worry about memory allocation failure, and sometimes a mempool isn't
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| 239 | * what you want.
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| 240 | *
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| 241 | * We treat the free elements as entries in a singly linked list, and the
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| 242 | * freelist as a stack - allocating and freeing push and pop off the freelist.
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| 243 |
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| 244 |
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| 245 | #define DECLARE_ARRAY_ALLOCATOR(type, name, size) \
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| 246 | struct { \
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| 247 | type *freelist; \
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| 248 | type data[size]; \
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| 249 | } name
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| 250 |
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| 251 | #define array_alloc(array) \
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| 252 | ({ \
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| 253 | typeof((array)->freelist) _ret = (array)->freelist; \
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| 254 | \
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| 255 | if (_ret) \
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| 256 | (array)->freelist = *((typeof((array)->freelist) *) _ret);\
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| 257 | \
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| 258 | _ret; \
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| 259 | })
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| 260 |
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| 261 | #define array_free(array, ptr) \
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| 262 | do { \
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| 263 | typeof((array)->freelist) _ptr = ptr; \
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| 264 | \
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| 265 | *((typeof((array)->freelist) *) _ptr) = (array)->freelist; \
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| 266 | (array)->freelist = _ptr; \
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| 267 | } while (0)
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| 268 |
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| 269 | #define array_allocator_init(array) \
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| 270 | do { \
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| 271 | typeof((array)->freelist) _i; \
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| 272 | \
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| 273 | BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *)); \
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| 274 | (array)->freelist = NULL; \
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| 275 | \
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| 276 | for (_i = (array)->data; \
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| 277 | _i < (array)->data + ARRAY_SIZE((array)->data); \
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| 278 | _i++) \
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| 279 | array_free(array, _i); \
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| 280 | } while (0)
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| 281 |
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| 282 | #define array_freelist_empty(array) ((array)->freelist == NULL)
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| 283 |
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| 284 | #define ANYSINT_MAX(t) \
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| 285 | ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
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| 286 |
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| 287 | int bch_strtoint_h(const char *cp, int *res);
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| 288 | int bch_strtouint_h(const char *cp, unsigned int *res);
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| 289 | int bch_strtoll_h(const char *cp, long long *res);
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| 290 | int bch_strtoull_h(const char *cp, unsigned long long *res);
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| 291 |
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| 292 | static inline int bch_strtol_h(const char *cp, long *res)
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| 293 | {
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| 294 | #if BITS_PER_LONG == 32
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| 295 | return bch_strtoint_h(cp, (int *) res);
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| 296 | #else
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| 297 | return bch_strtoll_h(cp, (long long *) res);
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| 298 | #endif
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| 299 | }
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| 300 |
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| 301 | static inline int bch_strtoul_h(const char *cp, long *res)
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| 302 | {
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| 303 | #if BITS_PER_LONG == 32
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| 304 | return bch_strtouint_h(cp, (unsigned int *) res);
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| 305 | #else
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| 306 | return bch_strtoull_h(cp, (unsigned long long *) res);
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| 307 | #endif
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| 308 | }
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| 309 |
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| 310 | #define strtoi_h(cp, res) \
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| 311 | (__builtin_types_compatible_p(typeof(*res), int) \
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| 312 | ? bch_strtoint_h(cp, (void *) res) \
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| 313 | : __builtin_types_compatible_p(typeof(*res), long) \
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| 314 | ? bch_strtol_h(cp, (void *) res) \
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| 315 | : __builtin_types_compatible_p(typeof(*res), long long) \
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| 316 | ? bch_strtoll_h(cp, (void *) res) \
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| 317 | : __builtin_types_compatible_p(typeof(*res), unsigned int) \
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| 318 | ? bch_strtouint_h(cp, (void *) res) \
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| 319 | : __builtin_types_compatible_p(typeof(*res), unsigned long) \
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| 320 | ? bch_strtoul_h(cp, (void *) res) \
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| 321 | : __builtin_types_compatible_p(typeof(*res), unsigned long long)\
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| 322 | ? bch_strtoull_h(cp, (void *) res) : -EINVAL)
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| 323 |
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| 324 | #define strtoul_safe(cp, var) \
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| 325 | ({ \
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| 326 | unsigned long _v; \
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| 327 | int _r = kstrtoul(cp, 10, &_v); \
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| 328 | if (!_r) \
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| 329 | var = _v; \
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| 330 | _r; \
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| 331 | })
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| 332 |
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| 333 | #define strtoul_safe_clamp(cp, var, min, max) \
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| 334 | ({ \
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| 335 | unsigned long _v; \
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| 336 | int _r = kstrtoul(cp, 10, &_v); \
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| 337 | if (!_r) \
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| 338 | var = clamp_t(typeof(var), _v, min, max); \
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| 339 | _r; \
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| 340 | })
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| 341 |
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| 342 | ssize_t bch_hprint(char *buf, int64_t v);
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| 343 |
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| 344 | bool bch_is_zero(const char *p, size_t n);
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| 345 | int bch_parse_uuid(const char *s, char *uuid);
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| 346 |
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| 347 | struct time_stats {
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| 348 | spinlock_t lock;
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| 349 | |
| 350 | * all fields are in nanoseconds, averages are ewmas stored left shifted
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| 351 | * by 8
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| 352 |
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| 353 | uint64_t max_duration;
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| 354 | uint64_t average_duration;
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| 355 | uint64_t average_frequency;
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| 356 | uint64_t last;
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| 357 | };
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| 358 |
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| 359 | void bch_time_stats_update(struct time_stats *stats, uint64_t time);
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| 360 |
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| 361 | static inline unsigned int local_clock_us(void)
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| 362 | {
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| 363 | return local_clock() >> 10;
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| 364 | }
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| 365 |
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| 366 | #define NSEC_PER_ns 1L
|
| 367 | #define NSEC_PER_us NSEC_PER_USEC
|
| 368 | #define NSEC_PER_ms NSEC_PER_MSEC
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| 369 | #define NSEC_PER_sec NSEC_PER_SEC
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| 370 |
|
| 371 | #define __print_time_stat(stats, name, stat, units) \
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| 372 | sysfs_print(name ## _ ## stat ## _ ## units, \
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| 373 | div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
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| 374 |
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| 375 | #define sysfs_print_time_stats(stats, name, \
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| 376 | frequency_units, \
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| 377 | duration_units) \
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| 378 | do { \
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| 379 | __print_time_stat(stats, name, \
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| 380 | average_frequency, frequency_units); \
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| 381 | __print_time_stat(stats, name, \
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| 382 | average_duration, duration_units); \
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| 383 | sysfs_print(name ## _ ##max_duration ## _ ## duration_units, \
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| 384 | div_u64((stats)->max_duration, \
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| 385 | NSEC_PER_ ## duration_units)); \
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| 386 | \
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| 387 | sysfs_print(name ## _last_ ## frequency_units, (stats)->last \
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| 388 | ? div_s64(local_clock() - (stats)->last, \
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| 389 | NSEC_PER_ ## frequency_units) \
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| 390 | : -1LL); \
|
| 391 | } while (0)
|
| 392 |
|
| 393 | #define sysfs_time_stats_attribute(name, \
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| 394 | frequency_units, \
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| 395 | duration_units) \
|
| 396 | read_attribute(name ## _average_frequency_ ## frequency_units); \
|
| 397 | read_attribute(name ## _average_duration_ ## duration_units); \
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| 398 | read_attribute(name ## _max_duration_ ## duration_units); \
|
| 399 | read_attribute(name ## _last_ ## frequency_units)
|
| 400 |
|
| 401 | #define sysfs_time_stats_attribute_list(name, \
|
| 402 | frequency_units, \
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| 403 | duration_units) \
|
| 404 | &sysfs_ ## name ## _average_frequency_ ## frequency_units, \
|
| 405 | &sysfs_ ## name ## _average_duration_ ## duration_units, \
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| 406 | &sysfs_ ## name ## _max_duration_ ## duration_units, \
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| 407 | &sysfs_ ## name ## _last_ ## frequency_units,
|
| 408 |
|
| 409 | #define ewma_add(ewma, val, weight, factor) \
|
| 410 | ({ \
|
| 411 | (ewma) *= (weight) - 1; \
|
| 412 | (ewma) += (val) << factor; \
|
| 413 | (ewma) /= (weight); \
|
| 414 | (ewma) >> factor; \
|
| 415 | })
|
| 416 |
|
| 417 | struct bch_ratelimit {
|
| 418 |
|
| 419 | uint64_t next;
|
| 420 |
|
| 421 | |
| 422 | * Rate at which we want to do work, in units per second
|
| 423 | * The units here correspond to the units passed to bch_next_delay()
|
| 424 |
|
| 425 | atomic_long_t rate;
|
| 426 | };
|
| 427 |
|
| 428 | static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
|
| 429 | {
|
| 430 | d->next = local_clock();
|
| 431 | }
|
| 432 |
|
| 433 | uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
|
| 434 |
|
| 435 | #define __DIV_SAFE(n, d, zero) \
|
| 436 | ({ \
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| 437 | typeof(n) _n = (n); \
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| 438 | typeof(d) _d = (d); \
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| 439 | _d ? _n / _d : zero; \
|
| 440 | })
|
| 441 |
|
| 442 | #define DIV_SAFE(n, d) __DIV_SAFE(n, d, 0)
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| 443 |
|
| 444 | #define container_of_or_null(ptr, type, member) \
|
| 445 | ({ \
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| 446 | typeof(ptr) _ptr = ptr; \
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| 447 | _ptr ? container_of(_ptr, type, member) : NULL; \
|
| 448 | })
|
| 449 |
|
| 450 | #define RB_INSERT(root, new, member, cmp) \
|
| 451 | ({ \
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| 452 | __label__ dup; \
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| 453 | struct rb_node **n = &(root)->rb_node, *parent = NULL; \
|
| 454 | typeof(new) this; \
|
| 455 | int res, ret = -1; \
|
| 456 | \
|
| 457 | while (*n) { \
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| 458 | parent = *n; \
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| 459 | this = container_of(*n, typeof(*(new)), member); \
|
| 460 | res = cmp(new, this); \
|
| 461 | if (!res) \
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| 462 | goto dup; \
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| 463 | n = res < 0 \
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| 464 | ? &(*n)->rb_left \
|
| 465 | : &(*n)->rb_right; \
|
| 466 | } \
|
| 467 | \
|
| 468 | rb_link_node(&(new)->member, parent, n); \
|
| 469 | rb_insert_color(&(new)->member, root); \
|
| 470 | ret = 0; \
|
| 471 | dup: \
|
| 472 | ret; \
|
| 473 | })
|
| 474 |
|
| 475 | #define RB_SEARCH(root, search, member, cmp) \
|
| 476 | ({ \
|
| 477 | struct rb_node *n = (root)->rb_node; \
|
| 478 | typeof(&(search)) this, ret = NULL; \
|
| 479 | int res; \
|
| 480 | \
|
| 481 | while (n) { \
|
| 482 | this = container_of(n, typeof(search), member); \
|
| 483 | res = cmp(&(search), this); \
|
| 484 | if (!res) { \
|
| 485 | ret = this; \
|
| 486 | break; \
|
| 487 | } \
|
| 488 | n = res < 0 \
|
| 489 | ? n->rb_left \
|
| 490 | : n->rb_right; \
|
| 491 | } \
|
| 492 | ret; \
|
| 493 | })
|
| 494 |
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| 495 | #define RB_GREATER(root, search, member, cmp) \
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| 496 | ({ \
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| 497 | struct rb_node *n = (root)->rb_node; \
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| 498 | typeof(&(search)) this, ret = NULL; \
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| 499 | int res; \
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| 500 | \
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| 501 | while (n) { \
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| 502 | this = container_of(n, typeof(search), member); \
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| 503 | res = cmp(&(search), this); \
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| 504 | if (res < 0) { \
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| 505 | ret = this; \
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| 506 | n = n->rb_left; \
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| 507 | } else \
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| 508 | n = n->rb_right; \
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| 509 | } \
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| 510 | ret; \
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| 511 | })
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| 512 |
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| 513 | #define RB_FIRST(root, type, member) \
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| 514 | container_of_or_null(rb_first(root), type, member)
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| 515 |
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| 516 | #define RB_LAST(root, type, member) \
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| 517 | container_of_or_null(rb_last(root), type, member)
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| 518 |
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| 519 | #define RB_NEXT(ptr, member) \
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| 520 | container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
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| 521 |
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| 522 | #define RB_PREV(ptr, member) \
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| 523 | container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
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| 524 |
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| 525 | static inline uint64_t bch_crc64(const void *p, size_t len)
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| 526 | {
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| 527 | uint64_t crc = 0xffffffffffffffffULL;
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| 528 |
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| 529 | crc = crc64_be(crc, p, len);
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| 530 | return crc ^ 0xffffffffffffffffULL;
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| 531 | }
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| 532 |
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| 533 | |
| 534 | * A stepwise-linear pseudo-exponential. This returns 1 << (x >>
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| 535 | * frac_bits), with the less-significant bits filled in by linear
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| 536 | * interpolation.
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| 537 | *
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| 538 | * This can also be interpreted as a floating-point number format,
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| 539 | * where the low frac_bits are the mantissa (with implicit leading
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| 540 | * 1 bit), and the more significant bits are the exponent.
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| 541 | * The return value is 1.mantissa * 2^exponent.
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| 542 | *
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| 543 | * The way this is used, fract_bits is 6 and the largest possible
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| 544 | * input is CONGESTED_MAX-1 = 1023 (exponent 16, mantissa 0x1.fc),
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| 545 | * so the maximum output is 0x1fc00.
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| 546 |
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| 547 | static inline unsigned int fract_exp_two(unsigned int x,
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| 548 | unsigned int fract_bits)
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| 549 | {
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| 550 | unsigned int mantissa = 1 << fract_bits;
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| 551 |
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| 552 | mantissa += x & (mantissa - 1);
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| 553 | x >>= fract_bits;
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| 554 |
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| 555 | return mantissa << x >> fract_bits;
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| 556 | }
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| 557 |
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| 558 | void bch_bio_map(struct bio *bio, void *base);
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| 559 | int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
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| 560 |
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| 561 | #endif
|