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 return bch2_bkey_to_bset_inlined(b, k);
43 * There are never duplicate live keys in the btree - but including keys that
44 * have been flagged as deleted (and will be cleaned up later) we _will_ see
47 * Thus the sort order is: usual key comparison first, but for keys that compare
48 * equal the deleted key(s) come first, and the (at most one) live version comes
51 * The main reason for this is insertion: to handle overwrites, we first iterate
52 * over keys that compare equal to our insert key, and then insert immediately
53 * prior to the first key greater than the key we're inserting - our insert
54 * position will be after all keys that compare equal to our insert key, which
55 * by the time we actually do the insert will all be deleted.
58 void bch2_dump_bset(struct bch_fs *c, struct btree *b,
59 struct bset *i, unsigned set)
61 struct bkey_packed *_k, *_n;
64 struct printbuf buf = PRINTBUF;
74 k = bkey_disassemble(b, _k, &uk);
78 bch2_bkey_val_to_text(&buf, c, k);
80 bch2_bkey_to_text(&buf, k.k);
81 printk(KERN_ERR "block %u key %5zu: %s\n", set,
82 _k->_data - i->_data, buf.buf);
84 if (_n == vstruct_last(i))
87 n = bkey_unpack_key(b, _n);
89 if (bpos_lt(n.p, k.k->p)) {
90 printk(KERN_ERR "Key skipped backwards\n");
94 if (!bkey_deleted(k.k) && bpos_eq(n.p, k.k->p))
95 printk(KERN_ERR "Duplicate keys\n");
101 void bch2_dump_btree_node(struct bch_fs *c, struct btree *b)
107 bch2_dump_bset(c, b, bset(b, t), t - b->set);
111 void bch2_dump_btree_node_iter(struct btree *b,
112 struct btree_node_iter *iter)
114 struct btree_node_iter_set *set;
115 struct printbuf buf = PRINTBUF;
117 printk(KERN_ERR "btree node iter with %u/%u sets:\n",
118 __btree_node_iter_used(iter), b->nsets);
120 btree_node_iter_for_each(iter, set) {
121 struct bkey_packed *k = __btree_node_offset_to_key(b, set->k);
122 struct bset_tree *t = bch2_bkey_to_bset(b, k);
123 struct bkey uk = bkey_unpack_key(b, k);
125 printbuf_reset(&buf);
126 bch2_bkey_to_text(&buf, &uk);
127 printk(KERN_ERR "set %zu key %u: %s\n",
128 t - b->set, set->k, buf.buf);
134 #ifdef CONFIG_BCACHEFS_DEBUG
136 void __bch2_verify_btree_nr_keys(struct btree *b)
139 struct bkey_packed *k;
140 struct btree_nr_keys nr = { 0 };
143 bset_tree_for_each_key(b, t, k)
144 if (!bkey_deleted(k))
145 btree_keys_account_key_add(&nr, t - b->set, k);
147 BUG_ON(memcmp(&nr, &b->nr, sizeof(nr)));
150 static void bch2_btree_node_iter_next_check(struct btree_node_iter *_iter,
153 struct btree_node_iter iter = *_iter;
154 const struct bkey_packed *k, *n;
156 k = bch2_btree_node_iter_peek_all(&iter, b);
157 __bch2_btree_node_iter_advance(&iter, b);
158 n = bch2_btree_node_iter_peek_all(&iter, b);
160 bkey_unpack_key(b, k);
163 bkey_iter_cmp(b, k, n) > 0) {
164 struct btree_node_iter_set *set;
165 struct bkey ku = bkey_unpack_key(b, k);
166 struct bkey nu = bkey_unpack_key(b, n);
167 struct printbuf buf1 = PRINTBUF;
168 struct printbuf buf2 = PRINTBUF;
170 bch2_dump_btree_node(NULL, b);
171 bch2_bkey_to_text(&buf1, &ku);
172 bch2_bkey_to_text(&buf2, &nu);
173 printk(KERN_ERR "out of order/overlapping:\n%s\n%s\n",
175 printk(KERN_ERR "iter was:");
177 btree_node_iter_for_each(_iter, set) {
178 struct bkey_packed *k = __btree_node_offset_to_key(b, set->k);
179 struct bset_tree *t = bch2_bkey_to_bset(b, k);
180 printk(" [%zi %zi]", t - b->set,
181 k->_data - bset(b, t)->_data);
187 void bch2_btree_node_iter_verify(struct btree_node_iter *iter,
190 struct btree_node_iter_set *set, *s2;
191 struct bkey_packed *k, *p;
194 if (bch2_btree_node_iter_end(iter))
197 /* Verify no duplicates: */
198 btree_node_iter_for_each(iter, set) {
199 BUG_ON(set->k > set->end);
200 btree_node_iter_for_each(iter, s2)
201 BUG_ON(set != s2 && set->end == s2->end);
204 /* Verify that set->end is correct: */
205 btree_node_iter_for_each(iter, set) {
207 if (set->end == t->end_offset)
211 BUG_ON(set->k < btree_bkey_first_offset(t) ||
212 set->k >= t->end_offset);
215 /* Verify iterator is sorted: */
216 btree_node_iter_for_each(iter, set)
217 BUG_ON(set != iter->data &&
218 btree_node_iter_cmp(b, set[-1], set[0]) > 0);
220 k = bch2_btree_node_iter_peek_all(iter, b);
222 for_each_bset(b, t) {
223 if (iter->data[0].end == t->end_offset)
226 p = bch2_bkey_prev_all(b, t,
227 bch2_btree_node_iter_bset_pos(iter, b, t));
229 BUG_ON(p && bkey_iter_cmp(b, k, p) < 0);
233 void bch2_verify_insert_pos(struct btree *b, struct bkey_packed *where,
234 struct bkey_packed *insert, unsigned clobber_u64s)
236 struct bset_tree *t = bch2_bkey_to_bset(b, where);
237 struct bkey_packed *prev = bch2_bkey_prev_all(b, t, where);
238 struct bkey_packed *next = (void *) (where->_data + clobber_u64s);
239 struct printbuf buf1 = PRINTBUF;
240 struct printbuf buf2 = PRINTBUF;
243 bkey_iter_cmp(b, prev, insert) > 0);
246 bkey_iter_cmp(b, prev, insert) > 0) {
247 struct bkey k1 = bkey_unpack_key(b, prev);
248 struct bkey k2 = bkey_unpack_key(b, insert);
250 bch2_dump_btree_node(NULL, b);
251 bch2_bkey_to_text(&buf1, &k1);
252 bch2_bkey_to_text(&buf2, &k2);
254 panic("prev > insert:\n"
261 BUG_ON(next != btree_bkey_last(b, t) &&
262 bkey_iter_cmp(b, insert, next) > 0);
264 if (next != btree_bkey_last(b, t) &&
265 bkey_iter_cmp(b, insert, next) > 0) {
266 struct bkey k1 = bkey_unpack_key(b, insert);
267 struct bkey k2 = bkey_unpack_key(b, next);
269 bch2_dump_btree_node(NULL, b);
270 bch2_bkey_to_text(&buf1, &k1);
271 bch2_bkey_to_text(&buf2, &k2);
273 panic("insert > next:\n"
283 static inline void bch2_btree_node_iter_next_check(struct btree_node_iter *iter,
288 /* Auxiliary search trees */
290 #define BFLOAT_FAILED_UNPACKED U8_MAX
291 #define BFLOAT_FAILED U8_MAX
298 #define BKEY_MANTISSA_BITS 16
300 static unsigned bkey_float_byte_offset(unsigned idx)
302 return idx * sizeof(struct bkey_float);
306 struct bkey_float f[0];
314 static unsigned bset_aux_tree_buf_end(const struct bset_tree *t)
316 BUG_ON(t->aux_data_offset == U16_MAX);
318 switch (bset_aux_tree_type(t)) {
319 case BSET_NO_AUX_TREE:
320 return t->aux_data_offset;
321 case BSET_RO_AUX_TREE:
322 return t->aux_data_offset +
323 DIV_ROUND_UP(t->size * sizeof(struct bkey_float) +
324 t->size * sizeof(u8), 8);
325 case BSET_RW_AUX_TREE:
326 return t->aux_data_offset +
327 DIV_ROUND_UP(sizeof(struct rw_aux_tree) * t->size, 8);
333 static unsigned bset_aux_tree_buf_start(const struct btree *b,
334 const struct bset_tree *t)
337 ? DIV_ROUND_UP(b->unpack_fn_len, 8)
338 : bset_aux_tree_buf_end(t - 1);
341 static void *__aux_tree_base(const struct btree *b,
342 const struct bset_tree *t)
344 return b->aux_data + t->aux_data_offset * 8;
347 static struct ro_aux_tree *ro_aux_tree_base(const struct btree *b,
348 const struct bset_tree *t)
350 EBUG_ON(bset_aux_tree_type(t) != BSET_RO_AUX_TREE);
352 return __aux_tree_base(b, t);
355 static u8 *ro_aux_tree_prev(const struct btree *b,
356 const struct bset_tree *t)
358 EBUG_ON(bset_aux_tree_type(t) != BSET_RO_AUX_TREE);
360 return __aux_tree_base(b, t) + bkey_float_byte_offset(t->size);
363 static struct bkey_float *bkey_float(const struct btree *b,
364 const struct bset_tree *t,
367 return ro_aux_tree_base(b, t)->f + idx;
370 static void bset_aux_tree_verify(const struct btree *b)
372 #ifdef CONFIG_BCACHEFS_DEBUG
373 const struct bset_tree *t;
375 for_each_bset(b, t) {
376 if (t->aux_data_offset == U16_MAX)
379 BUG_ON(t != b->set &&
380 t[-1].aux_data_offset == U16_MAX);
382 BUG_ON(t->aux_data_offset < bset_aux_tree_buf_start(b, t));
383 BUG_ON(t->aux_data_offset > btree_aux_data_u64s(b));
384 BUG_ON(bset_aux_tree_buf_end(t) > btree_aux_data_u64s(b));
389 void bch2_btree_keys_init(struct btree *b)
394 memset(&b->nr, 0, sizeof(b->nr));
396 for (i = 0; i < MAX_BSETS; i++)
397 b->set[i].data_offset = U16_MAX;
399 bch2_bset_set_no_aux_tree(b, b->set);
402 /* Binary tree stuff for auxiliary search trees */
405 * Cacheline/offset <-> bkey pointer arithmetic:
407 * t->tree is a binary search tree in an array; each node corresponds to a key
408 * in one cacheline in t->set (BSET_CACHELINE bytes).
410 * This means we don't have to store the full index of the key that a node in
411 * the binary tree points to; eytzinger1_to_inorder() gives us the cacheline, and
412 * then bkey_float->m gives us the offset within that cacheline, in units of 8
415 * cacheline_to_bkey() and friends abstract out all the pointer arithmetic to
418 * To construct the bfloat for an arbitrary key we need to know what the key
419 * immediately preceding it is: we have to check if the two keys differ in the
420 * bits we're going to store in bkey_float->mantissa. t->prev[j] stores the size
421 * of the previous key so we can walk backwards to it from t->tree[j]'s key.
424 static inline void *bset_cacheline(const struct btree *b,
425 const struct bset_tree *t,
428 return (void *) round_down((unsigned long) btree_bkey_first(b, t),
430 cacheline * BSET_CACHELINE;
433 static struct bkey_packed *cacheline_to_bkey(const struct btree *b,
434 const struct bset_tree *t,
438 return bset_cacheline(b, t, cacheline) + offset * 8;
441 static unsigned bkey_to_cacheline(const struct btree *b,
442 const struct bset_tree *t,
443 const struct bkey_packed *k)
445 return ((void *) k - bset_cacheline(b, t, 0)) / BSET_CACHELINE;
448 static ssize_t __bkey_to_cacheline_offset(const struct btree *b,
449 const struct bset_tree *t,
451 const struct bkey_packed *k)
453 return (u64 *) k - (u64 *) bset_cacheline(b, t, cacheline);
456 static unsigned bkey_to_cacheline_offset(const struct btree *b,
457 const struct bset_tree *t,
459 const struct bkey_packed *k)
461 size_t m = __bkey_to_cacheline_offset(b, t, cacheline, k);
467 static inline struct bkey_packed *tree_to_bkey(const struct btree *b,
468 const struct bset_tree *t,
471 return cacheline_to_bkey(b, t,
472 __eytzinger1_to_inorder(j, t->size - 1, t->extra),
473 bkey_float(b, t, j)->key_offset);
476 static struct bkey_packed *tree_to_prev_bkey(const struct btree *b,
477 const struct bset_tree *t,
480 unsigned prev_u64s = ro_aux_tree_prev(b, t)[j];
482 return (void *) (tree_to_bkey(b, t, j)->_data - prev_u64s);
485 static struct rw_aux_tree *rw_aux_tree(const struct btree *b,
486 const struct bset_tree *t)
488 EBUG_ON(bset_aux_tree_type(t) != BSET_RW_AUX_TREE);
490 return __aux_tree_base(b, t);
494 * For the write set - the one we're currently inserting keys into - we don't
495 * maintain a full search tree, we just keep a simple lookup table in t->prev.
497 static struct bkey_packed *rw_aux_to_bkey(const struct btree *b,
501 return __btree_node_offset_to_key(b, rw_aux_tree(b, t)[j].offset);
504 static void rw_aux_tree_set(const struct btree *b, struct bset_tree *t,
505 unsigned j, struct bkey_packed *k)
507 EBUG_ON(k >= btree_bkey_last(b, t));
509 rw_aux_tree(b, t)[j] = (struct rw_aux_tree) {
510 .offset = __btree_node_key_to_offset(b, k),
511 .k = bkey_unpack_pos(b, k),
515 static void bch2_bset_verify_rw_aux_tree(struct btree *b,
518 struct bkey_packed *k = btree_bkey_first(b, t);
521 if (!bch2_expensive_debug_checks)
524 BUG_ON(bset_has_ro_aux_tree(t));
526 if (!bset_has_rw_aux_tree(t))
530 BUG_ON(rw_aux_to_bkey(b, t, j) != k);
534 if (rw_aux_to_bkey(b, t, j) == k) {
535 BUG_ON(!bpos_eq(rw_aux_tree(b, t)[j].k,
536 bkey_unpack_pos(b, k)));
541 BUG_ON(rw_aux_tree(b, t)[j].offset <=
542 rw_aux_tree(b, t)[j - 1].offset);
546 BUG_ON(k >= btree_bkey_last(b, t));
550 /* returns idx of first entry >= offset: */
551 static unsigned rw_aux_tree_bsearch(struct btree *b,
555 unsigned bset_offs = offset - btree_bkey_first_offset(t);
556 unsigned bset_u64s = t->end_offset - btree_bkey_first_offset(t);
557 unsigned idx = bset_u64s ? bset_offs * t->size / bset_u64s : 0;
559 EBUG_ON(bset_aux_tree_type(t) != BSET_RW_AUX_TREE);
561 EBUG_ON(idx > t->size);
563 while (idx < t->size &&
564 rw_aux_tree(b, t)[idx].offset < offset)
568 rw_aux_tree(b, t)[idx - 1].offset >= offset)
571 EBUG_ON(idx < t->size &&
572 rw_aux_tree(b, t)[idx].offset < offset);
573 EBUG_ON(idx && rw_aux_tree(b, t)[idx - 1].offset >= offset);
574 EBUG_ON(idx + 1 < t->size &&
575 rw_aux_tree(b, t)[idx].offset ==
576 rw_aux_tree(b, t)[idx + 1].offset);
581 static inline unsigned bkey_mantissa(const struct bkey_packed *k,
582 const struct bkey_float *f,
587 EBUG_ON(!bkey_packed(k));
589 v = get_unaligned((u64 *) (((u8 *) k->_data) + (f->exponent >> 3)));
592 * In little endian, we're shifting off low bits (and then the bits we
593 * want are at the low end), in big endian we're shifting off high bits
594 * (and then the bits we want are at the high end, so we shift them
597 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
598 v >>= f->exponent & 7;
600 v >>= 64 - (f->exponent & 7) - BKEY_MANTISSA_BITS;
606 static inline void make_bfloat(struct btree *b, struct bset_tree *t,
608 struct bkey_packed *min_key,
609 struct bkey_packed *max_key)
611 struct bkey_float *f = bkey_float(b, t, j);
612 struct bkey_packed *m = tree_to_bkey(b, t, j);
613 struct bkey_packed *l = is_power_of_2(j)
615 : tree_to_prev_bkey(b, t, j >> ffs(j));
616 struct bkey_packed *r = is_power_of_2(j + 1)
618 : tree_to_bkey(b, t, j >> (ffz(j) + 1));
620 int shift, exponent, high_bit;
623 * for failed bfloats, the lookup code falls back to comparing against
627 if (!bkey_packed(l) || !bkey_packed(r) || !bkey_packed(m) ||
629 f->exponent = BFLOAT_FAILED_UNPACKED;
634 * The greatest differing bit of l and r is the first bit we must
635 * include in the bfloat mantissa we're creating in order to do
636 * comparisons - that bit always becomes the high bit of
637 * bfloat->mantissa, and thus the exponent we're calculating here is
638 * the position of what will become the low bit in bfloat->mantissa:
640 * Note that this may be negative - we may be running off the low end
641 * of the key: we handle this later:
643 high_bit = max(bch2_bkey_greatest_differing_bit(b, l, r),
644 min_t(unsigned, BKEY_MANTISSA_BITS, b->nr_key_bits) - 1);
645 exponent = high_bit - (BKEY_MANTISSA_BITS - 1);
648 * Then we calculate the actual shift value, from the start of the key
649 * (k->_data), to get the key bits starting at exponent:
651 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
652 shift = (int) (b->format.key_u64s * 64 - b->nr_key_bits) + exponent;
654 EBUG_ON(shift + BKEY_MANTISSA_BITS > b->format.key_u64s * 64);
656 shift = high_bit_offset +
661 EBUG_ON(shift < KEY_PACKED_BITS_START);
663 EBUG_ON(shift < 0 || shift >= BFLOAT_FAILED);
666 mantissa = bkey_mantissa(m, f, j);
669 * If we've got garbage bits, set them to all 1s - it's legal for the
670 * bfloat to compare larger than the original key, but not smaller:
673 mantissa |= ~(~0U << -exponent);
675 f->mantissa = mantissa;
678 /* bytes remaining - only valid for last bset: */
679 static unsigned __bset_tree_capacity(const struct btree *b, const struct bset_tree *t)
681 bset_aux_tree_verify(b);
683 return btree_aux_data_bytes(b) - t->aux_data_offset * sizeof(u64);
686 static unsigned bset_ro_tree_capacity(const struct btree *b, const struct bset_tree *t)
688 return __bset_tree_capacity(b, t) /
689 (sizeof(struct bkey_float) + sizeof(u8));
692 static unsigned bset_rw_tree_capacity(const struct btree *b, const struct bset_tree *t)
694 return __bset_tree_capacity(b, t) / sizeof(struct rw_aux_tree);
697 static noinline void __build_rw_aux_tree(struct btree *b, struct bset_tree *t)
699 struct bkey_packed *k;
702 t->extra = BSET_RW_AUX_TREE_VAL;
703 rw_aux_tree(b, t)[0].offset =
704 __btree_node_key_to_offset(b, btree_bkey_first(b, t));
706 bset_tree_for_each_key(b, t, k) {
707 if (t->size == bset_rw_tree_capacity(b, t))
710 if ((void *) k - (void *) rw_aux_to_bkey(b, t, t->size - 1) >
712 rw_aux_tree_set(b, t, t->size++, k);
716 static noinline void __build_ro_aux_tree(struct btree *b, struct bset_tree *t)
718 struct bkey_packed *prev = NULL, *k = btree_bkey_first(b, t);
719 struct bkey_i min_key, max_key;
720 unsigned j, cacheline = 1;
722 t->size = min(bkey_to_cacheline(b, t, btree_bkey_last(b, t)),
723 bset_ro_tree_capacity(b, t));
727 t->extra = BSET_NO_AUX_TREE_VAL;
731 t->extra = (t->size - rounddown_pow_of_two(t->size - 1)) << 1;
733 /* First we figure out where the first key in each cacheline is */
734 eytzinger1_for_each(j, t->size - 1) {
735 while (bkey_to_cacheline(b, t, k) < cacheline)
736 prev = k, k = bkey_next(k);
738 if (k >= btree_bkey_last(b, t)) {
739 /* XXX: this path sucks */
744 ro_aux_tree_prev(b, t)[j] = prev->u64s;
745 bkey_float(b, t, j)->key_offset =
746 bkey_to_cacheline_offset(b, t, cacheline++, k);
748 EBUG_ON(tree_to_prev_bkey(b, t, j) != prev);
749 EBUG_ON(tree_to_bkey(b, t, j) != k);
752 while (k != btree_bkey_last(b, t))
753 prev = k, k = bkey_next(k);
755 if (!bkey_pack_pos(bkey_to_packed(&min_key), b->data->min_key, b)) {
756 bkey_init(&min_key.k);
757 min_key.k.p = b->data->min_key;
760 if (!bkey_pack_pos(bkey_to_packed(&max_key), b->data->max_key, b)) {
761 bkey_init(&max_key.k);
762 max_key.k.p = b->data->max_key;
765 /* Then we build the tree */
766 eytzinger1_for_each(j, t->size - 1)
768 bkey_to_packed(&min_key),
769 bkey_to_packed(&max_key));
772 static void bset_alloc_tree(struct btree *b, struct bset_tree *t)
776 for (i = b->set; i != t; i++)
777 BUG_ON(bset_has_rw_aux_tree(i));
779 bch2_bset_set_no_aux_tree(b, t);
781 /* round up to next cacheline: */
782 t->aux_data_offset = round_up(bset_aux_tree_buf_start(b, t),
783 SMP_CACHE_BYTES / sizeof(u64));
785 bset_aux_tree_verify(b);
788 void bch2_bset_build_aux_tree(struct btree *b, struct bset_tree *t,
792 ? bset_has_rw_aux_tree(t)
793 : bset_has_ro_aux_tree(t))
796 bset_alloc_tree(b, t);
798 if (!__bset_tree_capacity(b, t))
802 __build_rw_aux_tree(b, t);
804 __build_ro_aux_tree(b, t);
806 bset_aux_tree_verify(b);
809 void bch2_bset_init_first(struct btree *b, struct bset *i)
815 memset(i, 0, sizeof(*i));
816 get_random_bytes(&i->seq, sizeof(i->seq));
817 SET_BSET_BIG_ENDIAN(i, CPU_BIG_ENDIAN);
819 t = &b->set[b->nsets++];
820 set_btree_bset(b, t, i);
823 void bch2_bset_init_next(struct bch_fs *c, struct btree *b,
824 struct btree_node_entry *bne)
826 struct bset *i = &bne->keys;
829 BUG_ON(bset_byte_offset(b, bne) >= btree_bytes(c));
830 BUG_ON((void *) bne < (void *) btree_bkey_last(b, bset_tree_last(b)));
831 BUG_ON(b->nsets >= MAX_BSETS);
833 memset(i, 0, sizeof(*i));
834 i->seq = btree_bset_first(b)->seq;
835 SET_BSET_BIG_ENDIAN(i, CPU_BIG_ENDIAN);
837 t = &b->set[b->nsets++];
838 set_btree_bset(b, t, i);
842 * find _some_ key in the same bset as @k that precedes @k - not necessarily the
843 * immediate predecessor:
845 static struct bkey_packed *__bkey_prev(struct btree *b, struct bset_tree *t,
846 struct bkey_packed *k)
848 struct bkey_packed *p;
852 EBUG_ON(k < btree_bkey_first(b, t) ||
853 k > btree_bkey_last(b, t));
855 if (k == btree_bkey_first(b, t))
858 switch (bset_aux_tree_type(t)) {
859 case BSET_NO_AUX_TREE:
860 p = btree_bkey_first(b, t);
862 case BSET_RO_AUX_TREE:
863 j = min_t(unsigned, t->size - 1, bkey_to_cacheline(b, t, k));
866 p = j ? tree_to_bkey(b, t,
867 __inorder_to_eytzinger1(j--,
868 t->size - 1, t->extra))
869 : btree_bkey_first(b, t);
872 case BSET_RW_AUX_TREE:
873 offset = __btree_node_key_to_offset(b, k);
874 j = rw_aux_tree_bsearch(b, t, offset);
875 p = j ? rw_aux_to_bkey(b, t, j - 1)
876 : btree_bkey_first(b, t);
883 struct bkey_packed *bch2_bkey_prev_filter(struct btree *b,
885 struct bkey_packed *k,
886 unsigned min_key_type)
888 struct bkey_packed *p, *i, *ret = NULL, *orig_k = k;
890 while ((p = __bkey_prev(b, t, k)) && !ret) {
891 for (i = p; i != k; i = bkey_next(i))
892 if (i->type >= min_key_type)
898 if (bch2_expensive_debug_checks) {
899 BUG_ON(ret >= orig_k);
903 : btree_bkey_first(b, t);
906 BUG_ON(i->type >= min_key_type);
914 static void bch2_bset_fix_lookup_table(struct btree *b,
916 struct bkey_packed *_where,
917 unsigned clobber_u64s,
920 int shift = new_u64s - clobber_u64s;
921 unsigned l, j, where = __btree_node_key_to_offset(b, _where);
923 EBUG_ON(bset_has_ro_aux_tree(t));
925 if (!bset_has_rw_aux_tree(t))
928 /* returns first entry >= where */
929 l = rw_aux_tree_bsearch(b, t, where);
931 if (!l) /* never delete first entry */
933 else if (l < t->size &&
934 where < t->end_offset &&
935 rw_aux_tree(b, t)[l].offset == where)
936 rw_aux_tree_set(b, t, l++, _where);
942 rw_aux_tree(b, t)[j].offset < where + clobber_u64s;
947 rw_aux_tree(b, t)[j].offset + shift ==
948 rw_aux_tree(b, t)[l - 1].offset)
951 memmove(&rw_aux_tree(b, t)[l],
952 &rw_aux_tree(b, t)[j],
953 (void *) &rw_aux_tree(b, t)[t->size] -
954 (void *) &rw_aux_tree(b, t)[j]);
957 for (j = l; j < t->size; j++)
958 rw_aux_tree(b, t)[j].offset += shift;
960 EBUG_ON(l < t->size &&
961 rw_aux_tree(b, t)[l].offset ==
962 rw_aux_tree(b, t)[l - 1].offset);
964 if (t->size < bset_rw_tree_capacity(b, t) &&
966 ? rw_aux_tree(b, t)[l].offset
968 rw_aux_tree(b, t)[l - 1].offset >
969 L1_CACHE_BYTES / sizeof(u64)) {
970 struct bkey_packed *start = rw_aux_to_bkey(b, t, l - 1);
971 struct bkey_packed *end = l < t->size
972 ? rw_aux_to_bkey(b, t, l)
973 : btree_bkey_last(b, t);
974 struct bkey_packed *k = start;
981 if ((void *) k - (void *) start >= L1_CACHE_BYTES) {
982 memmove(&rw_aux_tree(b, t)[l + 1],
983 &rw_aux_tree(b, t)[l],
984 (void *) &rw_aux_tree(b, t)[t->size] -
985 (void *) &rw_aux_tree(b, t)[l]);
987 rw_aux_tree_set(b, t, l, k);
993 bch2_bset_verify_rw_aux_tree(b, t);
994 bset_aux_tree_verify(b);
997 void bch2_bset_insert(struct btree *b,
998 struct btree_node_iter *iter,
999 struct bkey_packed *where,
1000 struct bkey_i *insert,
1001 unsigned clobber_u64s)
1003 struct bkey_format *f = &b->format;
1004 struct bset_tree *t = bset_tree_last(b);
1005 struct bkey_packed packed, *src = bkey_to_packed(insert);
1007 bch2_bset_verify_rw_aux_tree(b, t);
1008 bch2_verify_insert_pos(b, where, bkey_to_packed(insert), clobber_u64s);
1010 if (bch2_bkey_pack_key(&packed, &insert->k, f))
1013 if (!bkey_deleted(&insert->k))
1014 btree_keys_account_key_add(&b->nr, t - b->set, src);
1016 if (src->u64s != clobber_u64s) {
1017 u64 *src_p = where->_data + clobber_u64s;
1018 u64 *dst_p = where->_data + src->u64s;
1020 EBUG_ON((int) le16_to_cpu(bset(b, t)->u64s) <
1021 (int) clobber_u64s - src->u64s);
1023 memmove_u64s(dst_p, src_p, btree_bkey_last(b, t)->_data - src_p);
1024 le16_add_cpu(&bset(b, t)->u64s, src->u64s - clobber_u64s);
1025 set_btree_bset_end(b, t);
1028 memcpy_u64s(where, src,
1029 bkeyp_key_u64s(f, src));
1030 memcpy_u64s(bkeyp_val(f, where), &insert->v,
1031 bkeyp_val_u64s(f, src));
1033 if (src->u64s != clobber_u64s)
1034 bch2_bset_fix_lookup_table(b, t, where, clobber_u64s, src->u64s);
1036 bch2_verify_btree_nr_keys(b);
1039 void bch2_bset_delete(struct btree *b,
1040 struct bkey_packed *where,
1041 unsigned clobber_u64s)
1043 struct bset_tree *t = bset_tree_last(b);
1044 u64 *src_p = where->_data + clobber_u64s;
1045 u64 *dst_p = where->_data;
1047 bch2_bset_verify_rw_aux_tree(b, t);
1049 EBUG_ON(le16_to_cpu(bset(b, t)->u64s) < clobber_u64s);
1051 memmove_u64s_down(dst_p, src_p, btree_bkey_last(b, t)->_data - src_p);
1052 le16_add_cpu(&bset(b, t)->u64s, -clobber_u64s);
1053 set_btree_bset_end(b, t);
1055 bch2_bset_fix_lookup_table(b, t, where, clobber_u64s, 0);
1061 static struct bkey_packed *bset_search_write_set(const struct btree *b,
1062 struct bset_tree *t,
1063 struct bpos *search)
1065 unsigned l = 0, r = t->size;
1067 while (l + 1 != r) {
1068 unsigned m = (l + r) >> 1;
1070 if (bpos_lt(rw_aux_tree(b, t)[m].k, *search))
1076 return rw_aux_to_bkey(b, t, l);
1079 static inline void prefetch_four_cachelines(void *p)
1081 #ifdef CONFIG_X86_64
1082 asm("prefetcht0 (-127 + 64 * 0)(%0);"
1083 "prefetcht0 (-127 + 64 * 1)(%0);"
1084 "prefetcht0 (-127 + 64 * 2)(%0);"
1085 "prefetcht0 (-127 + 64 * 3)(%0);"
1089 prefetch(p + L1_CACHE_BYTES * 0);
1090 prefetch(p + L1_CACHE_BYTES * 1);
1091 prefetch(p + L1_CACHE_BYTES * 2);
1092 prefetch(p + L1_CACHE_BYTES * 3);
1096 static inline bool bkey_mantissa_bits_dropped(const struct btree *b,
1097 const struct bkey_float *f,
1100 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
1101 unsigned key_bits_start = b->format.key_u64s * 64 - b->nr_key_bits;
1103 return f->exponent > key_bits_start;
1105 unsigned key_bits_end = high_bit_offset + b->nr_key_bits;
1107 return f->exponent + BKEY_MANTISSA_BITS < key_bits_end;
1112 static struct bkey_packed *bset_search_tree(const struct btree *b,
1113 const struct bset_tree *t,
1114 const struct bpos *search,
1115 const struct bkey_packed *packed_search)
1117 struct ro_aux_tree *base = ro_aux_tree_base(b, t);
1118 struct bkey_float *f;
1119 struct bkey_packed *k;
1120 unsigned inorder, n = 1, l, r;
1124 if (likely(n << 4 < t->size))
1125 prefetch(&base->f[n << 4]);
1128 if (unlikely(f->exponent >= BFLOAT_FAILED))
1132 r = bkey_mantissa(packed_search, f, n);
1134 if (unlikely(l == r) && bkey_mantissa_bits_dropped(b, f, n))
1137 n = n * 2 + (l < r);
1140 k = tree_to_bkey(b, t, n);
1141 cmp = bkey_cmp_p_or_unp(b, k, packed_search, search);
1145 n = n * 2 + (cmp < 0);
1146 } while (n < t->size);
1148 inorder = __eytzinger1_to_inorder(n >> 1, t->size - 1, t->extra);
1151 * n would have been the node we recursed to - the low bit tells us if
1152 * we recursed left or recursed right.
1154 if (likely(!(n & 1))) {
1156 if (unlikely(!inorder))
1157 return btree_bkey_first(b, t);
1159 f = &base->f[eytzinger1_prev(n >> 1, t->size - 1)];
1162 return cacheline_to_bkey(b, t, inorder, f->key_offset);
1165 static __always_inline __flatten
1166 struct bkey_packed *__bch2_bset_search(struct btree *b,
1167 struct bset_tree *t,
1168 struct bpos *search,
1169 const struct bkey_packed *lossy_packed_search)
1173 * First, we search for a cacheline, then lastly we do a linear search
1174 * within that cacheline.
1176 * To search for the cacheline, there's three different possibilities:
1177 * * The set is too small to have a search tree, so we just do a linear
1178 * search over the whole set.
1179 * * The set is the one we're currently inserting into; keeping a full
1180 * auxiliary search tree up to date would be too expensive, so we
1181 * use a much simpler lookup table to do a binary search -
1182 * bset_search_write_set().
1183 * * Or we use the auxiliary search tree we constructed earlier -
1184 * bset_search_tree()
1187 switch (bset_aux_tree_type(t)) {
1188 case BSET_NO_AUX_TREE:
1189 return btree_bkey_first(b, t);
1190 case BSET_RW_AUX_TREE:
1191 return bset_search_write_set(b, t, search);
1192 case BSET_RO_AUX_TREE:
1193 return bset_search_tree(b, t, search, lossy_packed_search);
1199 static __always_inline __flatten
1200 struct bkey_packed *bch2_bset_search_linear(struct btree *b,
1201 struct bset_tree *t,
1202 struct bpos *search,
1203 struct bkey_packed *packed_search,
1204 const struct bkey_packed *lossy_packed_search,
1205 struct bkey_packed *m)
1207 if (lossy_packed_search)
1208 while (m != btree_bkey_last(b, t) &&
1209 bkey_iter_cmp_p_or_unp(b, m,
1210 lossy_packed_search, search) < 0)
1214 while (m != btree_bkey_last(b, t) &&
1215 bkey_iter_pos_cmp(b, m, search) < 0)
1218 if (bch2_expensive_debug_checks) {
1219 struct bkey_packed *prev = bch2_bkey_prev_all(b, t, m);
1222 bkey_iter_cmp_p_or_unp(b, prev,
1223 packed_search, search) >= 0);
1229 /* Btree node iterator */
1231 static inline void __bch2_btree_node_iter_push(struct btree_node_iter *iter,
1233 const struct bkey_packed *k,
1234 const struct bkey_packed *end)
1237 struct btree_node_iter_set *pos;
1239 btree_node_iter_for_each(iter, pos)
1242 BUG_ON(pos >= iter->data + ARRAY_SIZE(iter->data));
1243 *pos = (struct btree_node_iter_set) {
1244 __btree_node_key_to_offset(b, k),
1245 __btree_node_key_to_offset(b, end)
1250 void bch2_btree_node_iter_push(struct btree_node_iter *iter,
1252 const struct bkey_packed *k,
1253 const struct bkey_packed *end)
1255 __bch2_btree_node_iter_push(iter, b, k, end);
1256 bch2_btree_node_iter_sort(iter, b);
1259 noinline __flatten __cold
1260 static void btree_node_iter_init_pack_failed(struct btree_node_iter *iter,
1261 struct btree *b, struct bpos *search)
1263 struct bkey_packed *k;
1265 trace_bkey_pack_pos_fail(search);
1267 bch2_btree_node_iter_init_from_start(iter, b);
1269 while ((k = bch2_btree_node_iter_peek(iter, b)) &&
1270 bkey_iter_pos_cmp(b, k, search) < 0)
1271 bch2_btree_node_iter_advance(iter, b);
1275 * bch_btree_node_iter_init - initialize a btree node iterator, starting from a
1278 * Main entry point to the lookup code for individual btree nodes:
1282 * When you don't filter out deleted keys, btree nodes _do_ contain duplicate
1283 * keys. This doesn't matter for most code, but it does matter for lookups.
1285 * Some adjacent keys with a string of equal keys:
1288 * If you search for k, the lookup code isn't guaranteed to return you any
1289 * specific k. The lookup code is conceptually doing a binary search and
1290 * iterating backwards is very expensive so if the pivot happens to land at the
1291 * last k that's what you'll get.
1293 * This works out ok, but it's something to be aware of:
1295 * - For non extents, we guarantee that the live key comes last - see
1296 * btree_node_iter_cmp(), keys_out_of_order(). So the duplicates you don't
1297 * see will only be deleted keys you don't care about.
1299 * - For extents, deleted keys sort last (see the comment at the top of this
1300 * file). But when you're searching for extents, you actually want the first
1301 * key strictly greater than your search key - an extent that compares equal
1302 * to the search key is going to have 0 sectors after the search key.
1304 * But this does mean that we can't just search for
1305 * bpos_successor(start_of_range) to get the first extent that overlaps with
1306 * the range we want - if we're unlucky and there's an extent that ends
1307 * exactly where we searched, then there could be a deleted key at the same
1308 * position and we'd get that when we search instead of the preceding extent
1311 * So we've got to search for start_of_range, then after the lookup iterate
1312 * past any extents that compare equal to the position we searched for.
1315 void bch2_btree_node_iter_init(struct btree_node_iter *iter,
1316 struct btree *b, struct bpos *search)
1318 struct bkey_packed p, *packed_search = NULL;
1319 struct btree_node_iter_set *pos = iter->data;
1320 struct bkey_packed *k[MAX_BSETS];
1323 EBUG_ON(bpos_lt(*search, b->data->min_key));
1324 EBUG_ON(bpos_gt(*search, b->data->max_key));
1325 bset_aux_tree_verify(b);
1327 memset(iter, 0, sizeof(*iter));
1329 switch (bch2_bkey_pack_pos_lossy(&p, *search, b)) {
1330 case BKEY_PACK_POS_EXACT:
1333 case BKEY_PACK_POS_SMALLER:
1334 packed_search = NULL;
1336 case BKEY_PACK_POS_FAIL:
1337 btree_node_iter_init_pack_failed(iter, b, search);
1341 for (i = 0; i < b->nsets; i++) {
1342 k[i] = __bch2_bset_search(b, b->set + i, search, &p);
1343 prefetch_four_cachelines(k[i]);
1346 for (i = 0; i < b->nsets; i++) {
1347 struct bset_tree *t = b->set + i;
1348 struct bkey_packed *end = btree_bkey_last(b, t);
1350 k[i] = bch2_bset_search_linear(b, t, search,
1351 packed_search, &p, k[i]);
1353 *pos++ = (struct btree_node_iter_set) {
1354 __btree_node_key_to_offset(b, k[i]),
1355 __btree_node_key_to_offset(b, end)
1359 bch2_btree_node_iter_sort(iter, b);
1362 void bch2_btree_node_iter_init_from_start(struct btree_node_iter *iter,
1365 struct bset_tree *t;
1367 memset(iter, 0, sizeof(*iter));
1370 __bch2_btree_node_iter_push(iter, b,
1371 btree_bkey_first(b, t),
1372 btree_bkey_last(b, t));
1373 bch2_btree_node_iter_sort(iter, b);
1376 struct bkey_packed *bch2_btree_node_iter_bset_pos(struct btree_node_iter *iter,
1378 struct bset_tree *t)
1380 struct btree_node_iter_set *set;
1382 btree_node_iter_for_each(iter, set)
1383 if (set->end == t->end_offset)
1384 return __btree_node_offset_to_key(b, set->k);
1386 return btree_bkey_last(b, t);
1389 static inline bool btree_node_iter_sort_two(struct btree_node_iter *iter,
1395 if ((ret = (btree_node_iter_cmp(b,
1397 iter->data[first + 1]) > 0)))
1398 swap(iter->data[first], iter->data[first + 1]);
1402 void bch2_btree_node_iter_sort(struct btree_node_iter *iter,
1405 /* unrolled bubble sort: */
1407 if (!__btree_node_iter_set_end(iter, 2)) {
1408 btree_node_iter_sort_two(iter, b, 0);
1409 btree_node_iter_sort_two(iter, b, 1);
1412 if (!__btree_node_iter_set_end(iter, 1))
1413 btree_node_iter_sort_two(iter, b, 0);
1416 void bch2_btree_node_iter_set_drop(struct btree_node_iter *iter,
1417 struct btree_node_iter_set *set)
1419 struct btree_node_iter_set *last =
1420 iter->data + ARRAY_SIZE(iter->data) - 1;
1422 memmove(&set[0], &set[1], (void *) last - (void *) set);
1423 *last = (struct btree_node_iter_set) { 0, 0 };
1426 static inline void __bch2_btree_node_iter_advance(struct btree_node_iter *iter,
1429 iter->data->k += __bch2_btree_node_iter_peek_all(iter, b)->u64s;
1431 EBUG_ON(iter->data->k > iter->data->end);
1433 if (unlikely(__btree_node_iter_set_end(iter, 0))) {
1434 /* avoid an expensive memmove call: */
1435 iter->data[0] = iter->data[1];
1436 iter->data[1] = iter->data[2];
1437 iter->data[2] = (struct btree_node_iter_set) { 0, 0 };
1441 if (__btree_node_iter_set_end(iter, 1))
1444 if (!btree_node_iter_sort_two(iter, b, 0))
1447 if (__btree_node_iter_set_end(iter, 2))
1450 btree_node_iter_sort_two(iter, b, 1);
1453 void bch2_btree_node_iter_advance(struct btree_node_iter *iter,
1456 if (bch2_expensive_debug_checks) {
1457 bch2_btree_node_iter_verify(iter, b);
1458 bch2_btree_node_iter_next_check(iter, b);
1461 __bch2_btree_node_iter_advance(iter, b);
1467 struct bkey_packed *bch2_btree_node_iter_prev_all(struct btree_node_iter *iter,
1470 struct bkey_packed *k, *prev = NULL;
1471 struct btree_node_iter_set *set;
1472 struct bset_tree *t;
1475 if (bch2_expensive_debug_checks)
1476 bch2_btree_node_iter_verify(iter, b);
1478 for_each_bset(b, t) {
1479 k = bch2_bkey_prev_all(b, t,
1480 bch2_btree_node_iter_bset_pos(iter, b, t));
1482 (!prev || bkey_iter_cmp(b, k, prev) > 0)) {
1484 end = t->end_offset;
1492 * We're manually memmoving instead of just calling sort() to ensure the
1493 * prev we picked ends up in slot 0 - sort won't necessarily put it
1494 * there because of duplicate deleted keys:
1496 btree_node_iter_for_each(iter, set)
1497 if (set->end == end)
1500 BUG_ON(set != &iter->data[__btree_node_iter_used(iter)]);
1502 BUG_ON(set >= iter->data + ARRAY_SIZE(iter->data));
1504 memmove(&iter->data[1],
1506 (void *) set - (void *) &iter->data[0]);
1508 iter->data[0].k = __btree_node_key_to_offset(b, prev);
1509 iter->data[0].end = end;
1511 if (bch2_expensive_debug_checks)
1512 bch2_btree_node_iter_verify(iter, b);
1516 struct bkey_packed *bch2_btree_node_iter_prev(struct btree_node_iter *iter,
1519 struct bkey_packed *prev;
1522 prev = bch2_btree_node_iter_prev_all(iter, b);
1523 } while (prev && bkey_deleted(prev));
1528 struct bkey_s_c bch2_btree_node_iter_peek_unpack(struct btree_node_iter *iter,
1532 struct bkey_packed *k = bch2_btree_node_iter_peek(iter, b);
1534 return k ? bkey_disassemble(b, k, u) : bkey_s_c_null;
1539 void bch2_btree_keys_stats(struct btree *b, struct bset_stats *stats)
1541 struct bset_tree *t;
1543 for_each_bset(b, t) {
1544 enum bset_aux_tree_type type = bset_aux_tree_type(t);
1547 stats->sets[type].nr++;
1548 stats->sets[type].bytes += le16_to_cpu(bset(b, t)->u64s) *
1551 if (bset_has_ro_aux_tree(t)) {
1552 stats->floats += t->size - 1;
1554 for (j = 1; j < t->size; j++)
1556 bkey_float(b, t, j)->exponent ==
1562 void bch2_bfloat_to_text(struct printbuf *out, struct btree *b,
1563 struct bkey_packed *k)
1565 struct bset_tree *t = bch2_bkey_to_bset(b, k);
1567 unsigned j, inorder;
1569 if (!bset_has_ro_aux_tree(t))
1572 inorder = bkey_to_cacheline(b, t, k);
1573 if (!inorder || inorder >= t->size)
1576 j = __inorder_to_eytzinger1(inorder, t->size - 1, t->extra);
1577 if (k != tree_to_bkey(b, t, j))
1580 switch (bkey_float(b, t, j)->exponent) {
1582 uk = bkey_unpack_key(b, k);
1584 " failed unpacked at depth %u\n"
1587 bch2_bpos_to_text(out, uk.p);
1588 prt_printf(out, "\n");