1 // SPDX-License-Identifier: GPL-2.0
3 * Code for working with individual keys, and sorted sets of keys with in a
6 * Copyright 2012 Google, Inc.
10 #include "btree_cache.h"
12 #include "eytzinger.h"
15 #include <asm/unaligned.h>
16 #include <linux/console.h>
17 #include <linux/random.h>
18 #include <linux/prefetch.h>
21 #include "alloc_types.h"
22 #include <trace/events/bcachefs.h>
24 static inline void __bch2_btree_node_iter_advance(struct btree_node_iter *,
27 static inline unsigned __btree_node_iter_used(struct btree_node_iter *iter)
29 unsigned n = ARRAY_SIZE(iter->data);
31 while (n && __btree_node_iter_set_end(iter, n - 1))
37 struct bset_tree *bch2_bkey_to_bset(struct btree *b, struct bkey_packed *k)
39 unsigned offset = __btree_node_key_to_offset(b, k);
43 if (offset <= t->end_offset) {
44 EBUG_ON(offset < btree_bkey_first_offset(t));
52 * There are never duplicate live keys in the btree - but including keys that
53 * have been flagged as deleted (and will be cleaned up later) we _will_ see
56 * Thus the sort order is: usual key comparison first, but for keys that compare
57 * equal the deleted key(s) come first, and the (at most one) live version comes
60 * The main reason for this is insertion: to handle overwrites, we first iterate
61 * over keys that compare equal to our insert key, and then insert immediately
62 * prior to the first key greater than the key we're inserting - our insert
63 * position will be after all keys that compare equal to our insert key, which
64 * by the time we actually do the insert will all be deleted.
67 void bch2_dump_bset(struct bch_fs *c, struct btree *b,
68 struct bset *i, unsigned set)
70 struct bkey_packed *_k, *_n;
73 struct printbuf buf = PRINTBUF;
83 k = bkey_disassemble(b, _k, &uk);
87 bch2_bkey_val_to_text(&buf, c, k);
89 bch2_bkey_to_text(&buf, k.k);
90 printk(KERN_ERR "block %u key %5zu: %s\n", set,
91 _k->_data - i->_data, buf.buf);
93 if (_n == vstruct_last(i))
96 n = bkey_unpack_key(b, _n);
98 if (bpos_cmp(n.p, k.k->p) < 0) {
99 printk(KERN_ERR "Key skipped backwards\n");
103 if (!bkey_deleted(k.k) &&
104 !bpos_cmp(n.p, k.k->p))
105 printk(KERN_ERR "Duplicate keys\n");
111 void bch2_dump_btree_node(struct bch_fs *c, struct btree *b)
117 bch2_dump_bset(c, b, bset(b, t), t - b->set);
121 void bch2_dump_btree_node_iter(struct btree *b,
122 struct btree_node_iter *iter)
124 struct btree_node_iter_set *set;
125 struct printbuf buf = PRINTBUF;
127 printk(KERN_ERR "btree node iter with %u/%u sets:\n",
128 __btree_node_iter_used(iter), b->nsets);
130 btree_node_iter_for_each(iter, set) {
131 struct bkey_packed *k = __btree_node_offset_to_key(b, set->k);
132 struct bset_tree *t = bch2_bkey_to_bset(b, k);
133 struct bkey uk = bkey_unpack_key(b, k);
135 printbuf_reset(&buf);
136 bch2_bkey_to_text(&buf, &uk);
137 printk(KERN_ERR "set %zu key %u: %s\n",
138 t - b->set, set->k, buf.buf);
144 #ifdef CONFIG_BCACHEFS_DEBUG
146 void __bch2_verify_btree_nr_keys(struct btree *b)
149 struct bkey_packed *k;
150 struct btree_nr_keys nr = { 0 };
153 bset_tree_for_each_key(b, t, k)
154 if (!bkey_deleted(k))
155 btree_keys_account_key_add(&nr, t - b->set, k);
157 BUG_ON(memcmp(&nr, &b->nr, sizeof(nr)));
160 static void bch2_btree_node_iter_next_check(struct btree_node_iter *_iter,
163 struct btree_node_iter iter = *_iter;
164 const struct bkey_packed *k, *n;
166 k = bch2_btree_node_iter_peek_all(&iter, b);
167 __bch2_btree_node_iter_advance(&iter, b);
168 n = bch2_btree_node_iter_peek_all(&iter, b);
170 bkey_unpack_key(b, k);
173 bkey_iter_cmp(b, k, n) > 0) {
174 struct btree_node_iter_set *set;
175 struct bkey ku = bkey_unpack_key(b, k);
176 struct bkey nu = bkey_unpack_key(b, n);
177 struct printbuf buf1 = PRINTBUF;
178 struct printbuf buf2 = PRINTBUF;
180 bch2_dump_btree_node(NULL, b);
181 bch2_bkey_to_text(&buf1, &ku);
182 bch2_bkey_to_text(&buf2, &nu);
183 printk(KERN_ERR "out of order/overlapping:\n%s\n%s\n",
185 printk(KERN_ERR "iter was:");
187 btree_node_iter_for_each(_iter, set) {
188 struct bkey_packed *k = __btree_node_offset_to_key(b, set->k);
189 struct bset_tree *t = bch2_bkey_to_bset(b, k);
190 printk(" [%zi %zi]", t - b->set,
191 k->_data - bset(b, t)->_data);
197 void bch2_btree_node_iter_verify(struct btree_node_iter *iter,
200 struct btree_node_iter_set *set, *s2;
201 struct bkey_packed *k, *p;
204 if (bch2_btree_node_iter_end(iter))
207 /* Verify no duplicates: */
208 btree_node_iter_for_each(iter, set) {
209 BUG_ON(set->k > set->end);
210 btree_node_iter_for_each(iter, s2)
211 BUG_ON(set != s2 && set->end == s2->end);
214 /* Verify that set->end is correct: */
215 btree_node_iter_for_each(iter, set) {
217 if (set->end == t->end_offset)
221 BUG_ON(set->k < btree_bkey_first_offset(t) ||
222 set->k >= t->end_offset);
225 /* Verify iterator is sorted: */
226 btree_node_iter_for_each(iter, set)
227 BUG_ON(set != iter->data &&
228 btree_node_iter_cmp(b, set[-1], set[0]) > 0);
230 k = bch2_btree_node_iter_peek_all(iter, b);
232 for_each_bset(b, t) {
233 if (iter->data[0].end == t->end_offset)
236 p = bch2_bkey_prev_all(b, t,
237 bch2_btree_node_iter_bset_pos(iter, b, t));
239 BUG_ON(p && bkey_iter_cmp(b, k, p) < 0);
243 void bch2_verify_insert_pos(struct btree *b, struct bkey_packed *where,
244 struct bkey_packed *insert, unsigned clobber_u64s)
246 struct bset_tree *t = bch2_bkey_to_bset(b, where);
247 struct bkey_packed *prev = bch2_bkey_prev_all(b, t, where);
248 struct bkey_packed *next = (void *) (where->_data + clobber_u64s);
249 struct printbuf buf1 = PRINTBUF;
250 struct printbuf buf2 = PRINTBUF;
253 bkey_iter_cmp(b, prev, insert) > 0);
256 bkey_iter_cmp(b, prev, insert) > 0) {
257 struct bkey k1 = bkey_unpack_key(b, prev);
258 struct bkey k2 = bkey_unpack_key(b, insert);
260 bch2_dump_btree_node(NULL, b);
261 bch2_bkey_to_text(&buf1, &k1);
262 bch2_bkey_to_text(&buf2, &k2);
264 panic("prev > insert:\n"
271 BUG_ON(next != btree_bkey_last(b, t) &&
272 bkey_iter_cmp(b, insert, next) > 0);
274 if (next != btree_bkey_last(b, t) &&
275 bkey_iter_cmp(b, insert, next) > 0) {
276 struct bkey k1 = bkey_unpack_key(b, insert);
277 struct bkey k2 = bkey_unpack_key(b, next);
279 bch2_dump_btree_node(NULL, b);
280 bch2_bkey_to_text(&buf1, &k1);
281 bch2_bkey_to_text(&buf2, &k2);
283 panic("insert > next:\n"
293 static inline void bch2_btree_node_iter_next_check(struct btree_node_iter *iter,
298 /* Auxiliary search trees */
300 #define BFLOAT_FAILED_UNPACKED U8_MAX
301 #define BFLOAT_FAILED U8_MAX
308 #define BKEY_MANTISSA_BITS 16
310 static unsigned bkey_float_byte_offset(unsigned idx)
312 return idx * sizeof(struct bkey_float);
316 struct bkey_float f[0];
324 static unsigned bset_aux_tree_buf_end(const struct bset_tree *t)
326 BUG_ON(t->aux_data_offset == U16_MAX);
328 switch (bset_aux_tree_type(t)) {
329 case BSET_NO_AUX_TREE:
330 return t->aux_data_offset;
331 case BSET_RO_AUX_TREE:
332 return t->aux_data_offset +
333 DIV_ROUND_UP(t->size * sizeof(struct bkey_float) +
334 t->size * sizeof(u8), 8);
335 case BSET_RW_AUX_TREE:
336 return t->aux_data_offset +
337 DIV_ROUND_UP(sizeof(struct rw_aux_tree) * t->size, 8);
343 static unsigned bset_aux_tree_buf_start(const struct btree *b,
344 const struct bset_tree *t)
347 ? DIV_ROUND_UP(b->unpack_fn_len, 8)
348 : bset_aux_tree_buf_end(t - 1);
351 static void *__aux_tree_base(const struct btree *b,
352 const struct bset_tree *t)
354 return b->aux_data + t->aux_data_offset * 8;
357 static struct ro_aux_tree *ro_aux_tree_base(const struct btree *b,
358 const struct bset_tree *t)
360 EBUG_ON(bset_aux_tree_type(t) != BSET_RO_AUX_TREE);
362 return __aux_tree_base(b, t);
365 static u8 *ro_aux_tree_prev(const struct btree *b,
366 const struct bset_tree *t)
368 EBUG_ON(bset_aux_tree_type(t) != BSET_RO_AUX_TREE);
370 return __aux_tree_base(b, t) + bkey_float_byte_offset(t->size);
373 static struct bkey_float *bkey_float(const struct btree *b,
374 const struct bset_tree *t,
377 return ro_aux_tree_base(b, t)->f + idx;
380 static void bset_aux_tree_verify(const struct btree *b)
382 #ifdef CONFIG_BCACHEFS_DEBUG
383 const struct bset_tree *t;
385 for_each_bset(b, t) {
386 if (t->aux_data_offset == U16_MAX)
389 BUG_ON(t != b->set &&
390 t[-1].aux_data_offset == U16_MAX);
392 BUG_ON(t->aux_data_offset < bset_aux_tree_buf_start(b, t));
393 BUG_ON(t->aux_data_offset > btree_aux_data_u64s(b));
394 BUG_ON(bset_aux_tree_buf_end(t) > btree_aux_data_u64s(b));
399 void bch2_btree_keys_init(struct btree *b)
404 memset(&b->nr, 0, sizeof(b->nr));
406 for (i = 0; i < MAX_BSETS; i++)
407 b->set[i].data_offset = U16_MAX;
409 bch2_bset_set_no_aux_tree(b, b->set);
412 /* Binary tree stuff for auxiliary search trees */
415 * Cacheline/offset <-> bkey pointer arithmetic:
417 * t->tree is a binary search tree in an array; each node corresponds to a key
418 * in one cacheline in t->set (BSET_CACHELINE bytes).
420 * This means we don't have to store the full index of the key that a node in
421 * the binary tree points to; eytzinger1_to_inorder() gives us the cacheline, and
422 * then bkey_float->m gives us the offset within that cacheline, in units of 8
425 * cacheline_to_bkey() and friends abstract out all the pointer arithmetic to
428 * To construct the bfloat for an arbitrary key we need to know what the key
429 * immediately preceding it is: we have to check if the two keys differ in the
430 * bits we're going to store in bkey_float->mantissa. t->prev[j] stores the size
431 * of the previous key so we can walk backwards to it from t->tree[j]'s key.
434 static inline void *bset_cacheline(const struct btree *b,
435 const struct bset_tree *t,
438 return (void *) round_down((unsigned long) btree_bkey_first(b, t),
440 cacheline * BSET_CACHELINE;
443 static struct bkey_packed *cacheline_to_bkey(const struct btree *b,
444 const struct bset_tree *t,
448 return bset_cacheline(b, t, cacheline) + offset * 8;
451 static unsigned bkey_to_cacheline(const struct btree *b,
452 const struct bset_tree *t,
453 const struct bkey_packed *k)
455 return ((void *) k - bset_cacheline(b, t, 0)) / BSET_CACHELINE;
458 static ssize_t __bkey_to_cacheline_offset(const struct btree *b,
459 const struct bset_tree *t,
461 const struct bkey_packed *k)
463 return (u64 *) k - (u64 *) bset_cacheline(b, t, cacheline);
466 static unsigned bkey_to_cacheline_offset(const struct btree *b,
467 const struct bset_tree *t,
469 const struct bkey_packed *k)
471 size_t m = __bkey_to_cacheline_offset(b, t, cacheline, k);
477 static inline struct bkey_packed *tree_to_bkey(const struct btree *b,
478 const struct bset_tree *t,
481 return cacheline_to_bkey(b, t,
482 __eytzinger1_to_inorder(j, t->size - 1, t->extra),
483 bkey_float(b, t, j)->key_offset);
486 static struct bkey_packed *tree_to_prev_bkey(const struct btree *b,
487 const struct bset_tree *t,
490 unsigned prev_u64s = ro_aux_tree_prev(b, t)[j];
492 return (void *) (tree_to_bkey(b, t, j)->_data - prev_u64s);
495 static struct rw_aux_tree *rw_aux_tree(const struct btree *b,
496 const struct bset_tree *t)
498 EBUG_ON(bset_aux_tree_type(t) != BSET_RW_AUX_TREE);
500 return __aux_tree_base(b, t);
504 * For the write set - the one we're currently inserting keys into - we don't
505 * maintain a full search tree, we just keep a simple lookup table in t->prev.
507 static struct bkey_packed *rw_aux_to_bkey(const struct btree *b,
511 return __btree_node_offset_to_key(b, rw_aux_tree(b, t)[j].offset);
514 static void rw_aux_tree_set(const struct btree *b, struct bset_tree *t,
515 unsigned j, struct bkey_packed *k)
517 EBUG_ON(k >= btree_bkey_last(b, t));
519 rw_aux_tree(b, t)[j] = (struct rw_aux_tree) {
520 .offset = __btree_node_key_to_offset(b, k),
521 .k = bkey_unpack_pos(b, k),
525 static void bch2_bset_verify_rw_aux_tree(struct btree *b,
528 struct bkey_packed *k = btree_bkey_first(b, t);
531 if (!bch2_expensive_debug_checks)
534 BUG_ON(bset_has_ro_aux_tree(t));
536 if (!bset_has_rw_aux_tree(t))
540 BUG_ON(rw_aux_to_bkey(b, t, j) != k);
544 if (rw_aux_to_bkey(b, t, j) == k) {
545 BUG_ON(bpos_cmp(rw_aux_tree(b, t)[j].k,
546 bkey_unpack_pos(b, k)));
551 BUG_ON(rw_aux_tree(b, t)[j].offset <=
552 rw_aux_tree(b, t)[j - 1].offset);
556 BUG_ON(k >= btree_bkey_last(b, t));
560 /* returns idx of first entry >= offset: */
561 static unsigned rw_aux_tree_bsearch(struct btree *b,
565 unsigned bset_offs = offset - btree_bkey_first_offset(t);
566 unsigned bset_u64s = t->end_offset - btree_bkey_first_offset(t);
567 unsigned idx = bset_u64s ? bset_offs * t->size / bset_u64s : 0;
569 EBUG_ON(bset_aux_tree_type(t) != BSET_RW_AUX_TREE);
571 EBUG_ON(idx > t->size);
573 while (idx < t->size &&
574 rw_aux_tree(b, t)[idx].offset < offset)
578 rw_aux_tree(b, t)[idx - 1].offset >= offset)
581 EBUG_ON(idx < t->size &&
582 rw_aux_tree(b, t)[idx].offset < offset);
583 EBUG_ON(idx && rw_aux_tree(b, t)[idx - 1].offset >= offset);
584 EBUG_ON(idx + 1 < t->size &&
585 rw_aux_tree(b, t)[idx].offset ==
586 rw_aux_tree(b, t)[idx + 1].offset);
591 static inline unsigned bkey_mantissa(const struct bkey_packed *k,
592 const struct bkey_float *f,
597 EBUG_ON(!bkey_packed(k));
599 v = get_unaligned((u64 *) (((u8 *) k->_data) + (f->exponent >> 3)));
602 * In little endian, we're shifting off low bits (and then the bits we
603 * want are at the low end), in big endian we're shifting off high bits
604 * (and then the bits we want are at the high end, so we shift them
607 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
608 v >>= f->exponent & 7;
610 v >>= 64 - (f->exponent & 7) - BKEY_MANTISSA_BITS;
616 static inline void make_bfloat(struct btree *b, struct bset_tree *t,
618 struct bkey_packed *min_key,
619 struct bkey_packed *max_key)
621 struct bkey_float *f = bkey_float(b, t, j);
622 struct bkey_packed *m = tree_to_bkey(b, t, j);
623 struct bkey_packed *l = is_power_of_2(j)
625 : tree_to_prev_bkey(b, t, j >> ffs(j));
626 struct bkey_packed *r = is_power_of_2(j + 1)
628 : tree_to_bkey(b, t, j >> (ffz(j) + 1));
630 int shift, exponent, high_bit;
633 * for failed bfloats, the lookup code falls back to comparing against
637 if (!bkey_packed(l) || !bkey_packed(r) || !bkey_packed(m) ||
639 f->exponent = BFLOAT_FAILED_UNPACKED;
644 * The greatest differing bit of l and r is the first bit we must
645 * include in the bfloat mantissa we're creating in order to do
646 * comparisons - that bit always becomes the high bit of
647 * bfloat->mantissa, and thus the exponent we're calculating here is
648 * the position of what will become the low bit in bfloat->mantissa:
650 * Note that this may be negative - we may be running off the low end
651 * of the key: we handle this later:
653 high_bit = max(bch2_bkey_greatest_differing_bit(b, l, r),
654 min_t(unsigned, BKEY_MANTISSA_BITS, b->nr_key_bits) - 1);
655 exponent = high_bit - (BKEY_MANTISSA_BITS - 1);
658 * Then we calculate the actual shift value, from the start of the key
659 * (k->_data), to get the key bits starting at exponent:
661 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
662 shift = (int) (b->format.key_u64s * 64 - b->nr_key_bits) + exponent;
664 EBUG_ON(shift + BKEY_MANTISSA_BITS > b->format.key_u64s * 64);
666 shift = high_bit_offset +
671 EBUG_ON(shift < KEY_PACKED_BITS_START);
673 EBUG_ON(shift < 0 || shift >= BFLOAT_FAILED);
676 mantissa = bkey_mantissa(m, f, j);
679 * If we've got garbage bits, set them to all 1s - it's legal for the
680 * bfloat to compare larger than the original key, but not smaller:
683 mantissa |= ~(~0U << -exponent);
685 f->mantissa = mantissa;
688 /* bytes remaining - only valid for last bset: */
689 static unsigned __bset_tree_capacity(const struct btree *b, const struct bset_tree *t)
691 bset_aux_tree_verify(b);
693 return btree_aux_data_bytes(b) - t->aux_data_offset * sizeof(u64);
696 static unsigned bset_ro_tree_capacity(const struct btree *b, const struct bset_tree *t)
698 return __bset_tree_capacity(b, t) /
699 (sizeof(struct bkey_float) + sizeof(u8));
702 static unsigned bset_rw_tree_capacity(const struct btree *b, const struct bset_tree *t)
704 return __bset_tree_capacity(b, t) / sizeof(struct rw_aux_tree);
707 static noinline void __build_rw_aux_tree(struct btree *b, struct bset_tree *t)
709 struct bkey_packed *k;
712 t->extra = BSET_RW_AUX_TREE_VAL;
713 rw_aux_tree(b, t)[0].offset =
714 __btree_node_key_to_offset(b, btree_bkey_first(b, t));
716 bset_tree_for_each_key(b, t, k) {
717 if (t->size == bset_rw_tree_capacity(b, t))
720 if ((void *) k - (void *) rw_aux_to_bkey(b, t, t->size - 1) >
722 rw_aux_tree_set(b, t, t->size++, k);
726 static noinline void __build_ro_aux_tree(struct btree *b, struct bset_tree *t)
728 struct bkey_packed *prev = NULL, *k = btree_bkey_first(b, t);
729 struct bkey_i min_key, max_key;
730 unsigned j, cacheline = 1;
732 t->size = min(bkey_to_cacheline(b, t, btree_bkey_last(b, t)),
733 bset_ro_tree_capacity(b, t));
737 t->extra = BSET_NO_AUX_TREE_VAL;
741 t->extra = (t->size - rounddown_pow_of_two(t->size - 1)) << 1;
743 /* First we figure out where the first key in each cacheline is */
744 eytzinger1_for_each(j, t->size - 1) {
745 while (bkey_to_cacheline(b, t, k) < cacheline)
746 prev = k, k = bkey_next(k);
748 if (k >= btree_bkey_last(b, t)) {
749 /* XXX: this path sucks */
754 ro_aux_tree_prev(b, t)[j] = prev->u64s;
755 bkey_float(b, t, j)->key_offset =
756 bkey_to_cacheline_offset(b, t, cacheline++, k);
758 EBUG_ON(tree_to_prev_bkey(b, t, j) != prev);
759 EBUG_ON(tree_to_bkey(b, t, j) != k);
762 while (k != btree_bkey_last(b, t))
763 prev = k, k = bkey_next(k);
765 if (!bkey_pack_pos(bkey_to_packed(&min_key), b->data->min_key, b)) {
766 bkey_init(&min_key.k);
767 min_key.k.p = b->data->min_key;
770 if (!bkey_pack_pos(bkey_to_packed(&max_key), b->data->max_key, b)) {
771 bkey_init(&max_key.k);
772 max_key.k.p = b->data->max_key;
775 /* Then we build the tree */
776 eytzinger1_for_each(j, t->size - 1)
778 bkey_to_packed(&min_key),
779 bkey_to_packed(&max_key));
782 static void bset_alloc_tree(struct btree *b, struct bset_tree *t)
786 for (i = b->set; i != t; i++)
787 BUG_ON(bset_has_rw_aux_tree(i));
789 bch2_bset_set_no_aux_tree(b, t);
791 /* round up to next cacheline: */
792 t->aux_data_offset = round_up(bset_aux_tree_buf_start(b, t),
793 SMP_CACHE_BYTES / sizeof(u64));
795 bset_aux_tree_verify(b);
798 void bch2_bset_build_aux_tree(struct btree *b, struct bset_tree *t,
802 ? bset_has_rw_aux_tree(t)
803 : bset_has_ro_aux_tree(t))
806 bset_alloc_tree(b, t);
808 if (!__bset_tree_capacity(b, t))
812 __build_rw_aux_tree(b, t);
814 __build_ro_aux_tree(b, t);
816 bset_aux_tree_verify(b);
819 void bch2_bset_init_first(struct btree *b, struct bset *i)
825 memset(i, 0, sizeof(*i));
826 get_random_bytes(&i->seq, sizeof(i->seq));
827 SET_BSET_BIG_ENDIAN(i, CPU_BIG_ENDIAN);
829 t = &b->set[b->nsets++];
830 set_btree_bset(b, t, i);
833 void bch2_bset_init_next(struct bch_fs *c, struct btree *b,
834 struct btree_node_entry *bne)
836 struct bset *i = &bne->keys;
839 BUG_ON(bset_byte_offset(b, bne) >= btree_bytes(c));
840 BUG_ON((void *) bne < (void *) btree_bkey_last(b, bset_tree_last(b)));
841 BUG_ON(b->nsets >= MAX_BSETS);
843 memset(i, 0, sizeof(*i));
844 i->seq = btree_bset_first(b)->seq;
845 SET_BSET_BIG_ENDIAN(i, CPU_BIG_ENDIAN);
847 t = &b->set[b->nsets++];
848 set_btree_bset(b, t, i);
852 * find _some_ key in the same bset as @k that precedes @k - not necessarily the
853 * immediate predecessor:
855 static struct bkey_packed *__bkey_prev(struct btree *b, struct bset_tree *t,
856 struct bkey_packed *k)
858 struct bkey_packed *p;
862 EBUG_ON(k < btree_bkey_first(b, t) ||
863 k > btree_bkey_last(b, t));
865 if (k == btree_bkey_first(b, t))
868 switch (bset_aux_tree_type(t)) {
869 case BSET_NO_AUX_TREE:
870 p = btree_bkey_first(b, t);
872 case BSET_RO_AUX_TREE:
873 j = min_t(unsigned, t->size - 1, bkey_to_cacheline(b, t, k));
876 p = j ? tree_to_bkey(b, t,
877 __inorder_to_eytzinger1(j--,
878 t->size - 1, t->extra))
879 : btree_bkey_first(b, t);
882 case BSET_RW_AUX_TREE:
883 offset = __btree_node_key_to_offset(b, k);
884 j = rw_aux_tree_bsearch(b, t, offset);
885 p = j ? rw_aux_to_bkey(b, t, j - 1)
886 : btree_bkey_first(b, t);
893 struct bkey_packed *bch2_bkey_prev_filter(struct btree *b,
895 struct bkey_packed *k,
896 unsigned min_key_type)
898 struct bkey_packed *p, *i, *ret = NULL, *orig_k = k;
900 while ((p = __bkey_prev(b, t, k)) && !ret) {
901 for (i = p; i != k; i = bkey_next(i))
902 if (i->type >= min_key_type)
908 if (bch2_expensive_debug_checks) {
909 BUG_ON(ret >= orig_k);
913 : btree_bkey_first(b, t);
916 BUG_ON(i->type >= min_key_type);
924 static void bch2_bset_fix_lookup_table(struct btree *b,
926 struct bkey_packed *_where,
927 unsigned clobber_u64s,
930 int shift = new_u64s - clobber_u64s;
931 unsigned l, j, where = __btree_node_key_to_offset(b, _where);
933 EBUG_ON(bset_has_ro_aux_tree(t));
935 if (!bset_has_rw_aux_tree(t))
938 /* returns first entry >= where */
939 l = rw_aux_tree_bsearch(b, t, where);
941 if (!l) /* never delete first entry */
943 else if (l < t->size &&
944 where < t->end_offset &&
945 rw_aux_tree(b, t)[l].offset == where)
946 rw_aux_tree_set(b, t, l++, _where);
952 rw_aux_tree(b, t)[j].offset < where + clobber_u64s;
957 rw_aux_tree(b, t)[j].offset + shift ==
958 rw_aux_tree(b, t)[l - 1].offset)
961 memmove(&rw_aux_tree(b, t)[l],
962 &rw_aux_tree(b, t)[j],
963 (void *) &rw_aux_tree(b, t)[t->size] -
964 (void *) &rw_aux_tree(b, t)[j]);
967 for (j = l; j < t->size; j++)
968 rw_aux_tree(b, t)[j].offset += shift;
970 EBUG_ON(l < t->size &&
971 rw_aux_tree(b, t)[l].offset ==
972 rw_aux_tree(b, t)[l - 1].offset);
974 if (t->size < bset_rw_tree_capacity(b, t) &&
976 ? rw_aux_tree(b, t)[l].offset
978 rw_aux_tree(b, t)[l - 1].offset >
979 L1_CACHE_BYTES / sizeof(u64)) {
980 struct bkey_packed *start = rw_aux_to_bkey(b, t, l - 1);
981 struct bkey_packed *end = l < t->size
982 ? rw_aux_to_bkey(b, t, l)
983 : btree_bkey_last(b, t);
984 struct bkey_packed *k = start;
991 if ((void *) k - (void *) start >= L1_CACHE_BYTES) {
992 memmove(&rw_aux_tree(b, t)[l + 1],
993 &rw_aux_tree(b, t)[l],
994 (void *) &rw_aux_tree(b, t)[t->size] -
995 (void *) &rw_aux_tree(b, t)[l]);
997 rw_aux_tree_set(b, t, l, k);
1003 bch2_bset_verify_rw_aux_tree(b, t);
1004 bset_aux_tree_verify(b);
1007 void bch2_bset_insert(struct btree *b,
1008 struct btree_node_iter *iter,
1009 struct bkey_packed *where,
1010 struct bkey_i *insert,
1011 unsigned clobber_u64s)
1013 struct bkey_format *f = &b->format;
1014 struct bset_tree *t = bset_tree_last(b);
1015 struct bkey_packed packed, *src = bkey_to_packed(insert);
1017 bch2_bset_verify_rw_aux_tree(b, t);
1018 bch2_verify_insert_pos(b, where, bkey_to_packed(insert), clobber_u64s);
1020 if (bch2_bkey_pack_key(&packed, &insert->k, f))
1023 if (!bkey_deleted(&insert->k))
1024 btree_keys_account_key_add(&b->nr, t - b->set, src);
1026 if (src->u64s != clobber_u64s) {
1027 u64 *src_p = where->_data + clobber_u64s;
1028 u64 *dst_p = where->_data + src->u64s;
1030 EBUG_ON((int) le16_to_cpu(bset(b, t)->u64s) <
1031 (int) clobber_u64s - src->u64s);
1033 memmove_u64s(dst_p, src_p, btree_bkey_last(b, t)->_data - src_p);
1034 le16_add_cpu(&bset(b, t)->u64s, src->u64s - clobber_u64s);
1035 set_btree_bset_end(b, t);
1038 memcpy_u64s(where, src,
1039 bkeyp_key_u64s(f, src));
1040 memcpy_u64s(bkeyp_val(f, where), &insert->v,
1041 bkeyp_val_u64s(f, src));
1043 if (src->u64s != clobber_u64s)
1044 bch2_bset_fix_lookup_table(b, t, where, clobber_u64s, src->u64s);
1046 bch2_verify_btree_nr_keys(b);
1049 void bch2_bset_delete(struct btree *b,
1050 struct bkey_packed *where,
1051 unsigned clobber_u64s)
1053 struct bset_tree *t = bset_tree_last(b);
1054 u64 *src_p = where->_data + clobber_u64s;
1055 u64 *dst_p = where->_data;
1057 bch2_bset_verify_rw_aux_tree(b, t);
1059 EBUG_ON(le16_to_cpu(bset(b, t)->u64s) < clobber_u64s);
1061 memmove_u64s_down(dst_p, src_p, btree_bkey_last(b, t)->_data - src_p);
1062 le16_add_cpu(&bset(b, t)->u64s, -clobber_u64s);
1063 set_btree_bset_end(b, t);
1065 bch2_bset_fix_lookup_table(b, t, where, clobber_u64s, 0);
1071 static struct bkey_packed *bset_search_write_set(const struct btree *b,
1072 struct bset_tree *t,
1073 struct bpos *search)
1075 unsigned l = 0, r = t->size;
1077 while (l + 1 != r) {
1078 unsigned m = (l + r) >> 1;
1080 if (bpos_cmp(rw_aux_tree(b, t)[m].k, *search) < 0)
1086 return rw_aux_to_bkey(b, t, l);
1089 static inline void prefetch_four_cachelines(void *p)
1091 #ifdef CONFIG_X86_64
1092 asm("prefetcht0 (-127 + 64 * 0)(%0);"
1093 "prefetcht0 (-127 + 64 * 1)(%0);"
1094 "prefetcht0 (-127 + 64 * 2)(%0);"
1095 "prefetcht0 (-127 + 64 * 3)(%0);"
1099 prefetch(p + L1_CACHE_BYTES * 0);
1100 prefetch(p + L1_CACHE_BYTES * 1);
1101 prefetch(p + L1_CACHE_BYTES * 2);
1102 prefetch(p + L1_CACHE_BYTES * 3);
1106 static inline bool bkey_mantissa_bits_dropped(const struct btree *b,
1107 const struct bkey_float *f,
1110 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
1111 unsigned key_bits_start = b->format.key_u64s * 64 - b->nr_key_bits;
1113 return f->exponent > key_bits_start;
1115 unsigned key_bits_end = high_bit_offset + b->nr_key_bits;
1117 return f->exponent + BKEY_MANTISSA_BITS < key_bits_end;
1122 static struct bkey_packed *bset_search_tree(const struct btree *b,
1123 const struct bset_tree *t,
1124 const struct bpos *search,
1125 const struct bkey_packed *packed_search)
1127 struct ro_aux_tree *base = ro_aux_tree_base(b, t);
1128 struct bkey_float *f;
1129 struct bkey_packed *k;
1130 unsigned inorder, n = 1, l, r;
1134 if (likely(n << 4 < t->size))
1135 prefetch(&base->f[n << 4]);
1138 if (unlikely(f->exponent >= BFLOAT_FAILED))
1142 r = bkey_mantissa(packed_search, f, n);
1144 if (unlikely(l == r) && bkey_mantissa_bits_dropped(b, f, n))
1147 n = n * 2 + (l < r);
1150 k = tree_to_bkey(b, t, n);
1151 cmp = bkey_cmp_p_or_unp(b, k, packed_search, search);
1155 n = n * 2 + (cmp < 0);
1156 } while (n < t->size);
1158 inorder = __eytzinger1_to_inorder(n >> 1, t->size - 1, t->extra);
1161 * n would have been the node we recursed to - the low bit tells us if
1162 * we recursed left or recursed right.
1164 if (likely(!(n & 1))) {
1166 if (unlikely(!inorder))
1167 return btree_bkey_first(b, t);
1169 f = &base->f[eytzinger1_prev(n >> 1, t->size - 1)];
1172 return cacheline_to_bkey(b, t, inorder, f->key_offset);
1175 static __always_inline __flatten
1176 struct bkey_packed *__bch2_bset_search(struct btree *b,
1177 struct bset_tree *t,
1178 struct bpos *search,
1179 const struct bkey_packed *lossy_packed_search)
1183 * First, we search for a cacheline, then lastly we do a linear search
1184 * within that cacheline.
1186 * To search for the cacheline, there's three different possibilities:
1187 * * The set is too small to have a search tree, so we just do a linear
1188 * search over the whole set.
1189 * * The set is the one we're currently inserting into; keeping a full
1190 * auxiliary search tree up to date would be too expensive, so we
1191 * use a much simpler lookup table to do a binary search -
1192 * bset_search_write_set().
1193 * * Or we use the auxiliary search tree we constructed earlier -
1194 * bset_search_tree()
1197 switch (bset_aux_tree_type(t)) {
1198 case BSET_NO_AUX_TREE:
1199 return btree_bkey_first(b, t);
1200 case BSET_RW_AUX_TREE:
1201 return bset_search_write_set(b, t, search);
1202 case BSET_RO_AUX_TREE:
1203 return bset_search_tree(b, t, search, lossy_packed_search);
1209 static __always_inline __flatten
1210 struct bkey_packed *bch2_bset_search_linear(struct btree *b,
1211 struct bset_tree *t,
1212 struct bpos *search,
1213 struct bkey_packed *packed_search,
1214 const struct bkey_packed *lossy_packed_search,
1215 struct bkey_packed *m)
1217 if (lossy_packed_search)
1218 while (m != btree_bkey_last(b, t) &&
1219 bkey_iter_cmp_p_or_unp(b, m,
1220 lossy_packed_search, search) < 0)
1224 while (m != btree_bkey_last(b, t) &&
1225 bkey_iter_pos_cmp(b, m, search) < 0)
1228 if (bch2_expensive_debug_checks) {
1229 struct bkey_packed *prev = bch2_bkey_prev_all(b, t, m);
1232 bkey_iter_cmp_p_or_unp(b, prev,
1233 packed_search, search) >= 0);
1239 /* Btree node iterator */
1241 static inline void __bch2_btree_node_iter_push(struct btree_node_iter *iter,
1243 const struct bkey_packed *k,
1244 const struct bkey_packed *end)
1247 struct btree_node_iter_set *pos;
1249 btree_node_iter_for_each(iter, pos)
1252 BUG_ON(pos >= iter->data + ARRAY_SIZE(iter->data));
1253 *pos = (struct btree_node_iter_set) {
1254 __btree_node_key_to_offset(b, k),
1255 __btree_node_key_to_offset(b, end)
1260 void bch2_btree_node_iter_push(struct btree_node_iter *iter,
1262 const struct bkey_packed *k,
1263 const struct bkey_packed *end)
1265 __bch2_btree_node_iter_push(iter, b, k, end);
1266 bch2_btree_node_iter_sort(iter, b);
1269 noinline __flatten __cold
1270 static void btree_node_iter_init_pack_failed(struct btree_node_iter *iter,
1271 struct btree *b, struct bpos *search)
1273 struct bkey_packed *k;
1275 trace_bkey_pack_pos_fail(search);
1277 bch2_btree_node_iter_init_from_start(iter, b);
1279 while ((k = bch2_btree_node_iter_peek(iter, b)) &&
1280 bkey_iter_pos_cmp(b, k, search) < 0)
1281 bch2_btree_node_iter_advance(iter, b);
1285 * bch_btree_node_iter_init - initialize a btree node iterator, starting from a
1288 * Main entry point to the lookup code for individual btree nodes:
1292 * When you don't filter out deleted keys, btree nodes _do_ contain duplicate
1293 * keys. This doesn't matter for most code, but it does matter for lookups.
1295 * Some adjacent keys with a string of equal keys:
1298 * If you search for k, the lookup code isn't guaranteed to return you any
1299 * specific k. The lookup code is conceptually doing a binary search and
1300 * iterating backwards is very expensive so if the pivot happens to land at the
1301 * last k that's what you'll get.
1303 * This works out ok, but it's something to be aware of:
1305 * - For non extents, we guarantee that the live key comes last - see
1306 * btree_node_iter_cmp(), keys_out_of_order(). So the duplicates you don't
1307 * see will only be deleted keys you don't care about.
1309 * - For extents, deleted keys sort last (see the comment at the top of this
1310 * file). But when you're searching for extents, you actually want the first
1311 * key strictly greater than your search key - an extent that compares equal
1312 * to the search key is going to have 0 sectors after the search key.
1314 * But this does mean that we can't just search for
1315 * bpos_successor(start_of_range) to get the first extent that overlaps with
1316 * the range we want - if we're unlucky and there's an extent that ends
1317 * exactly where we searched, then there could be a deleted key at the same
1318 * position and we'd get that when we search instead of the preceding extent
1321 * So we've got to search for start_of_range, then after the lookup iterate
1322 * past any extents that compare equal to the position we searched for.
1325 void bch2_btree_node_iter_init(struct btree_node_iter *iter,
1326 struct btree *b, struct bpos *search)
1328 struct bkey_packed p, *packed_search = NULL;
1329 struct btree_node_iter_set *pos = iter->data;
1330 struct bkey_packed *k[MAX_BSETS];
1333 EBUG_ON(bpos_cmp(*search, b->data->min_key) < 0);
1334 EBUG_ON(bpos_cmp(*search, b->data->max_key) > 0);
1335 bset_aux_tree_verify(b);
1337 memset(iter, 0, sizeof(*iter));
1339 switch (bch2_bkey_pack_pos_lossy(&p, *search, b)) {
1340 case BKEY_PACK_POS_EXACT:
1343 case BKEY_PACK_POS_SMALLER:
1344 packed_search = NULL;
1346 case BKEY_PACK_POS_FAIL:
1347 btree_node_iter_init_pack_failed(iter, b, search);
1351 for (i = 0; i < b->nsets; i++) {
1352 k[i] = __bch2_bset_search(b, b->set + i, search, &p);
1353 prefetch_four_cachelines(k[i]);
1356 for (i = 0; i < b->nsets; i++) {
1357 struct bset_tree *t = b->set + i;
1358 struct bkey_packed *end = btree_bkey_last(b, t);
1360 k[i] = bch2_bset_search_linear(b, t, search,
1361 packed_search, &p, k[i]);
1363 *pos++ = (struct btree_node_iter_set) {
1364 __btree_node_key_to_offset(b, k[i]),
1365 __btree_node_key_to_offset(b, end)
1369 bch2_btree_node_iter_sort(iter, b);
1372 void bch2_btree_node_iter_init_from_start(struct btree_node_iter *iter,
1375 struct bset_tree *t;
1377 memset(iter, 0, sizeof(*iter));
1380 __bch2_btree_node_iter_push(iter, b,
1381 btree_bkey_first(b, t),
1382 btree_bkey_last(b, t));
1383 bch2_btree_node_iter_sort(iter, b);
1386 struct bkey_packed *bch2_btree_node_iter_bset_pos(struct btree_node_iter *iter,
1388 struct bset_tree *t)
1390 struct btree_node_iter_set *set;
1392 btree_node_iter_for_each(iter, set)
1393 if (set->end == t->end_offset)
1394 return __btree_node_offset_to_key(b, set->k);
1396 return btree_bkey_last(b, t);
1399 static inline bool btree_node_iter_sort_two(struct btree_node_iter *iter,
1405 if ((ret = (btree_node_iter_cmp(b,
1407 iter->data[first + 1]) > 0)))
1408 swap(iter->data[first], iter->data[first + 1]);
1412 void bch2_btree_node_iter_sort(struct btree_node_iter *iter,
1415 /* unrolled bubble sort: */
1417 if (!__btree_node_iter_set_end(iter, 2)) {
1418 btree_node_iter_sort_two(iter, b, 0);
1419 btree_node_iter_sort_two(iter, b, 1);
1422 if (!__btree_node_iter_set_end(iter, 1))
1423 btree_node_iter_sort_two(iter, b, 0);
1426 void bch2_btree_node_iter_set_drop(struct btree_node_iter *iter,
1427 struct btree_node_iter_set *set)
1429 struct btree_node_iter_set *last =
1430 iter->data + ARRAY_SIZE(iter->data) - 1;
1432 memmove(&set[0], &set[1], (void *) last - (void *) set);
1433 *last = (struct btree_node_iter_set) { 0, 0 };
1436 static inline void __bch2_btree_node_iter_advance(struct btree_node_iter *iter,
1439 iter->data->k += __bch2_btree_node_iter_peek_all(iter, b)->u64s;
1441 EBUG_ON(iter->data->k > iter->data->end);
1443 if (unlikely(__btree_node_iter_set_end(iter, 0))) {
1444 /* avoid an expensive memmove call: */
1445 iter->data[0] = iter->data[1];
1446 iter->data[1] = iter->data[2];
1447 iter->data[2] = (struct btree_node_iter_set) { 0, 0 };
1451 if (__btree_node_iter_set_end(iter, 1))
1454 if (!btree_node_iter_sort_two(iter, b, 0))
1457 if (__btree_node_iter_set_end(iter, 2))
1460 btree_node_iter_sort_two(iter, b, 1);
1463 void bch2_btree_node_iter_advance(struct btree_node_iter *iter,
1466 if (bch2_expensive_debug_checks) {
1467 bch2_btree_node_iter_verify(iter, b);
1468 bch2_btree_node_iter_next_check(iter, b);
1471 __bch2_btree_node_iter_advance(iter, b);
1477 struct bkey_packed *bch2_btree_node_iter_prev_all(struct btree_node_iter *iter,
1480 struct bkey_packed *k, *prev = NULL;
1481 struct btree_node_iter_set *set;
1482 struct bset_tree *t;
1485 if (bch2_expensive_debug_checks)
1486 bch2_btree_node_iter_verify(iter, b);
1488 for_each_bset(b, t) {
1489 k = bch2_bkey_prev_all(b, t,
1490 bch2_btree_node_iter_bset_pos(iter, b, t));
1492 (!prev || bkey_iter_cmp(b, k, prev) > 0)) {
1494 end = t->end_offset;
1502 * We're manually memmoving instead of just calling sort() to ensure the
1503 * prev we picked ends up in slot 0 - sort won't necessarily put it
1504 * there because of duplicate deleted keys:
1506 btree_node_iter_for_each(iter, set)
1507 if (set->end == end)
1510 BUG_ON(set != &iter->data[__btree_node_iter_used(iter)]);
1512 BUG_ON(set >= iter->data + ARRAY_SIZE(iter->data));
1514 memmove(&iter->data[1],
1516 (void *) set - (void *) &iter->data[0]);
1518 iter->data[0].k = __btree_node_key_to_offset(b, prev);
1519 iter->data[0].end = end;
1521 if (bch2_expensive_debug_checks)
1522 bch2_btree_node_iter_verify(iter, b);
1526 struct bkey_packed *bch2_btree_node_iter_prev(struct btree_node_iter *iter,
1529 struct bkey_packed *prev;
1532 prev = bch2_btree_node_iter_prev_all(iter, b);
1533 } while (prev && bkey_deleted(prev));
1538 struct bkey_s_c bch2_btree_node_iter_peek_unpack(struct btree_node_iter *iter,
1542 struct bkey_packed *k = bch2_btree_node_iter_peek(iter, b);
1544 return k ? bkey_disassemble(b, k, u) : bkey_s_c_null;
1549 void bch2_btree_keys_stats(struct btree *b, struct bset_stats *stats)
1551 struct bset_tree *t;
1553 for_each_bset(b, t) {
1554 enum bset_aux_tree_type type = bset_aux_tree_type(t);
1557 stats->sets[type].nr++;
1558 stats->sets[type].bytes += le16_to_cpu(bset(b, t)->u64s) *
1561 if (bset_has_ro_aux_tree(t)) {
1562 stats->floats += t->size - 1;
1564 for (j = 1; j < t->size; j++)
1566 bkey_float(b, t, j)->exponent ==
1572 void bch2_bfloat_to_text(struct printbuf *out, struct btree *b,
1573 struct bkey_packed *k)
1575 struct bset_tree *t = bch2_bkey_to_bset(b, k);
1577 unsigned j, inorder;
1579 if (!bset_has_ro_aux_tree(t))
1582 inorder = bkey_to_cacheline(b, t, k);
1583 if (!inorder || inorder >= t->size)
1586 j = __inorder_to_eytzinger1(inorder, t->size - 1, t->extra);
1587 if (k != tree_to_bkey(b, t, j))
1590 switch (bkey_float(b, t, j)->exponent) {
1592 uk = bkey_unpack_key(b, k);
1594 " failed unpacked at depth %u\n"
1597 bch2_bpos_to_text(out, uk.p);
1598 prt_printf(out, "\n");