1 // SPDX-License-Identifier: GPL-2.0
3 * Assorted bcachefs debug code
5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
6 * Copyright 2012 Google, Inc.
10 #include "bkey_methods.h"
11 #include "btree_cache.h"
13 #include "btree_iter.h"
14 #include "btree_locking.h"
15 #include "btree_update.h"
24 #include <linux/console.h>
25 #include <linux/debugfs.h>
26 #include <linux/module.h>
27 #include <linux/random.h>
28 #include <linux/seq_file.h>
30 static struct dentry *bch_debug;
32 static bool bch2_btree_verify_replica(struct bch_fs *c, struct btree *b,
33 struct extent_ptr_decoded pick)
35 struct btree *v = c->verify_data;
36 struct btree_node *n_ondisk = c->verify_ondisk;
37 struct btree_node *n_sorted = c->verify_data->data;
38 struct bset *sorted, *inmemory = &b->data->keys;
39 struct bch_dev *ca = bch_dev_bkey_exists(c, pick.ptr.dev);
41 bool failed = false, saw_error = false;
43 if (!bch2_dev_get_ioref(ca, READ))
46 bio = bio_alloc_bioset(ca->disk_sb.bdev,
47 buf_pages(n_sorted, btree_bytes(c)),
51 bio->bi_iter.bi_sector = pick.ptr.offset;
52 bch2_bio_map(bio, n_sorted, btree_bytes(c));
57 percpu_ref_put(&ca->io_ref);
59 memcpy(n_ondisk, n_sorted, btree_bytes(c));
62 if (bch2_btree_node_read_done(c, ca, v, false, &saw_error) || saw_error)
65 n_sorted = c->verify_data->data;
66 sorted = &n_sorted->keys;
68 if (inmemory->u64s != sorted->u64s ||
69 memcmp(inmemory->start,
71 vstruct_end(inmemory) - (void *) inmemory->start)) {
72 unsigned offset = 0, sectors;
78 printk(KERN_ERR "*** in memory:\n");
79 bch2_dump_bset(c, b, inmemory, 0);
81 printk(KERN_ERR "*** read back in:\n");
82 bch2_dump_bset(c, v, sorted, 0);
84 while (offset < v->written) {
87 sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
90 struct btree_node_entry *bne =
91 (void *) n_ondisk + (offset << 9);
94 sectors = vstruct_blocks(bne, c->block_bits) <<
98 printk(KERN_ERR "*** on disk block %u:\n", offset);
99 bch2_dump_bset(c, b, i, offset);
104 for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
105 if (inmemory->_data[j] != sorted->_data[j])
109 bch_err(c, "verify failed at key %u", j);
114 if (v->written != b->written) {
115 bch_err(c, "written wrong: expected %u, got %u",
116 b->written, v->written);
123 void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
125 struct bkey_ptrs_c ptrs;
126 struct extent_ptr_decoded p;
127 const union bch_extent_entry *entry;
129 struct bset *inmemory = &b->data->keys;
130 struct bkey_packed *k;
133 if (c->opts.nochanges)
136 bch2_btree_node_io_lock(b);
137 mutex_lock(&c->verify_lock);
139 if (!c->verify_ondisk) {
140 c->verify_ondisk = kvpmalloc(btree_bytes(c), GFP_KERNEL);
141 if (!c->verify_ondisk)
145 if (!c->verify_data) {
146 c->verify_data = __bch2_btree_node_mem_alloc(c);
150 list_del_init(&c->verify_data->list);
153 BUG_ON(b->nsets != 1);
155 for (k = inmemory->start; k != vstruct_last(inmemory); k = bkey_p_next(k))
156 if (k->type == KEY_TYPE_btree_ptr_v2)
157 ((struct bch_btree_ptr_v2 *) bkeyp_val(&b->format, k))->mem_ptr = 0;
160 bkey_copy(&v->key, &b->key);
161 v->c.level = b->c.level;
162 v->c.btree_id = b->c.btree_id;
163 bch2_btree_keys_init(v);
165 ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(&b->key));
166 bkey_for_each_ptr_decode(&b->key.k, ptrs, p, entry)
167 failed |= bch2_btree_verify_replica(c, b, p);
170 struct printbuf buf = PRINTBUF;
172 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
173 bch2_fs_fatal_error(c, "btree node verify failed for : %s\n", buf.buf);
177 mutex_unlock(&c->verify_lock);
178 bch2_btree_node_io_unlock(b);
181 void bch2_btree_node_ondisk_to_text(struct printbuf *out, struct bch_fs *c,
182 const struct btree *b)
184 struct btree_node *n_ondisk = NULL;
185 struct extent_ptr_decoded pick;
187 struct bio *bio = NULL;
191 if (bch2_bkey_pick_read_device(c, bkey_i_to_s_c(&b->key), NULL, &pick) <= 0) {
192 prt_printf(out, "error getting device to read from: invalid device\n");
196 ca = bch_dev_bkey_exists(c, pick.ptr.dev);
197 if (!bch2_dev_get_ioref(ca, READ)) {
198 prt_printf(out, "error getting device to read from: not online\n");
202 n_ondisk = kvpmalloc(btree_bytes(c), GFP_KERNEL);
204 prt_printf(out, "memory allocation failure\n");
208 bio = bio_alloc_bioset(ca->disk_sb.bdev,
209 buf_pages(n_ondisk, btree_bytes(c)),
210 REQ_OP_READ|REQ_META,
213 bio->bi_iter.bi_sector = pick.ptr.offset;
214 bch2_bio_map(bio, n_ondisk, btree_bytes(c));
216 ret = submit_bio_wait(bio);
218 prt_printf(out, "IO error reading btree node: %s\n", bch2_err_str(ret));
222 while (offset < btree_sectors(c)) {
225 struct bch_csum csum;
226 struct bkey_packed *k;
232 if (!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i))) {
233 prt_printf(out, "unknown checksum type at offset %u: %llu\n",
234 offset, BSET_CSUM_TYPE(i));
238 nonce = btree_nonce(i, offset << 9);
239 csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, n_ondisk);
241 if (bch2_crc_cmp(csum, n_ondisk->csum)) {
242 prt_printf(out, "invalid checksum\n");
246 bset_encrypt(c, i, offset << 9);
248 sectors = vstruct_sectors(n_ondisk, c->block_bits);
250 struct btree_node_entry *bne = (void *) n_ondisk + (offset << 9);
254 if (i->seq != n_ondisk->keys.seq)
257 if (!bch2_checksum_type_valid(c, BSET_CSUM_TYPE(i))) {
258 prt_printf(out, "unknown checksum type at offset %u: %llu\n",
259 offset, BSET_CSUM_TYPE(i));
263 nonce = btree_nonce(i, offset << 9);
264 csum = csum_vstruct(c, BSET_CSUM_TYPE(i), nonce, bne);
266 if (bch2_crc_cmp(csum, bne->csum)) {
267 prt_printf(out, "invalid checksum");
271 bset_encrypt(c, i, offset << 9);
273 sectors = vstruct_sectors(bne, c->block_bits);
276 prt_printf(out, " offset %u version %u, journal seq %llu\n",
278 le16_to_cpu(i->version),
279 le64_to_cpu(i->journal_seq));
282 printbuf_indent_add(out, 4);
284 for (k = i->start; k != vstruct_last(i); k = bkey_p_next(k)) {
287 bch2_bkey_val_to_text(out, c, bkey_disassemble(b, k, &u));
291 printbuf_indent_sub(out, 4);
296 kvpfree(n_ondisk, btree_bytes(c));
297 percpu_ref_put(&ca->io_ref);
300 #ifdef CONFIG_DEBUG_FS
302 /* XXX: bch_fs refcounting */
308 struct bpos prev_node;
313 char __user *ubuf; /* destination user buffer */
314 size_t size; /* size of requested read */
315 ssize_t ret; /* bytes read so far */
318 static ssize_t flush_buf(struct dump_iter *i)
321 size_t bytes = min_t(size_t, i->buf.pos, i->size);
322 int copied = bytes - copy_to_user(i->ubuf, i->buf.buf, bytes);
327 i->buf.pos -= copied;
328 memmove(i->buf.buf, i->buf.buf + copied, i->buf.pos);
334 return i->size ? 0 : i->ret;
337 static int bch2_dump_open(struct inode *inode, struct file *file)
339 struct btree_debug *bd = inode->i_private;
342 i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
346 file->private_data = i;
349 i->c = container_of(bd, struct bch_fs, btree_debug[bd->id]);
356 static int bch2_dump_release(struct inode *inode, struct file *file)
358 struct dump_iter *i = file->private_data;
360 printbuf_exit(&i->buf);
365 static ssize_t bch2_read_btree(struct file *file, char __user *buf,
366 size_t size, loff_t *ppos)
368 struct dump_iter *i = file->private_data;
369 struct btree_trans *trans;
370 struct btree_iter iter;
382 trans = bch2_trans_get(i->c);
383 ret = for_each_btree_key(trans, iter, i->id, i->from,
385 BTREE_ITER_ALL_SNAPSHOTS, k, ({
386 bch2_bkey_val_to_text(&i->buf, i->c, k);
387 prt_newline(&i->buf);
388 bch2_trans_unlock(trans);
393 bch2_trans_put(trans);
398 return ret ?: i->ret;
401 static const struct file_operations btree_debug_ops = {
402 .owner = THIS_MODULE,
403 .open = bch2_dump_open,
404 .release = bch2_dump_release,
405 .read = bch2_read_btree,
408 static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
409 size_t size, loff_t *ppos)
411 struct dump_iter *i = file->private_data;
412 struct btree_trans *trans;
413 struct btree_iter iter;
425 if (bpos_eq(SPOS_MAX, i->from))
428 trans = bch2_trans_get(i->c);
430 bch2_trans_begin(trans);
432 for_each_btree_node(trans, iter, i->id, i->from, 0, b, ret) {
433 bch2_btree_node_to_text(&i->buf, i->c, b);
434 i->from = !bpos_eq(SPOS_MAX, b->key.k.p)
435 ? bpos_successor(b->key.k.p)
438 ret = drop_locks_do(trans, flush_buf(i));
442 bch2_trans_iter_exit(trans, &iter);
444 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
447 bch2_trans_put(trans);
452 return ret ?: i->ret;
455 static const struct file_operations btree_format_debug_ops = {
456 .owner = THIS_MODULE,
457 .open = bch2_dump_open,
458 .release = bch2_dump_release,
459 .read = bch2_read_btree_formats,
462 static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
463 size_t size, loff_t *ppos)
465 struct dump_iter *i = file->private_data;
466 struct btree_trans *trans;
467 struct btree_iter iter;
479 trans = bch2_trans_get(i->c);
481 ret = for_each_btree_key(trans, iter, i->id, i->from,
483 BTREE_ITER_ALL_SNAPSHOTS, k, ({
484 struct btree_path_level *l =
485 &btree_iter_path(trans, &iter)->l[0];
486 struct bkey_packed *_k =
487 bch2_btree_node_iter_peek(&l->iter, l->b);
489 if (bpos_gt(l->b->key.k.p, i->prev_node)) {
490 bch2_btree_node_to_text(&i->buf, i->c, l->b);
491 i->prev_node = l->b->key.k.p;
494 bch2_bfloat_to_text(&i->buf, l->b, _k);
495 bch2_trans_unlock(trans);
500 bch2_trans_put(trans);
505 return ret ?: i->ret;
508 static const struct file_operations bfloat_failed_debug_ops = {
509 .owner = THIS_MODULE,
510 .open = bch2_dump_open,
511 .release = bch2_dump_release,
512 .read = bch2_read_bfloat_failed,
515 static void bch2_cached_btree_node_to_text(struct printbuf *out, struct bch_fs *c,
518 if (!out->nr_tabstops)
519 printbuf_tabstop_push(out, 32);
521 prt_printf(out, "%px btree=%s l=%u ",
523 bch2_btree_id_str(b->c.btree_id),
527 printbuf_indent_add(out, 2);
529 bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(&b->key));
532 prt_printf(out, "flags: ");
534 prt_bitflags(out, bch2_btree_node_flags, b->flags);
537 prt_printf(out, "pcpu read locks: ");
539 prt_printf(out, "%u", b->c.lock.readers != NULL);
542 prt_printf(out, "written:");
544 prt_printf(out, "%u", b->written);
547 prt_printf(out, "writes blocked:");
549 prt_printf(out, "%u", !list_empty_careful(&b->write_blocked));
552 prt_printf(out, "will make reachable:");
554 prt_printf(out, "%lx", b->will_make_reachable);
557 prt_printf(out, "journal pin %px:", &b->writes[0].journal);
559 prt_printf(out, "%llu", b->writes[0].journal.seq);
562 prt_printf(out, "journal pin %px:", &b->writes[1].journal);
564 prt_printf(out, "%llu", b->writes[1].journal.seq);
567 printbuf_indent_sub(out, 2);
570 static ssize_t bch2_cached_btree_nodes_read(struct file *file, char __user *buf,
571 size_t size, loff_t *ppos)
573 struct dump_iter *i = file->private_data;
574 struct bch_fs *c = i->c;
583 struct bucket_table *tbl;
584 struct rhash_head *pos;
593 tbl = rht_dereference_rcu(c->btree_cache.table.tbl,
594 &c->btree_cache.table);
595 if (i->iter < tbl->size) {
596 rht_for_each_entry_rcu(b, pos, tbl, i->iter, hash)
597 bch2_cached_btree_node_to_text(&i->buf, c, b);
606 if (i->buf.allocation_failure)
612 return ret ?: i->ret;
615 static const struct file_operations cached_btree_nodes_ops = {
616 .owner = THIS_MODULE,
617 .open = bch2_dump_open,
618 .release = bch2_dump_release,
619 .read = bch2_cached_btree_nodes_read,
622 static ssize_t bch2_btree_transactions_read(struct file *file, char __user *buf,
623 size_t size, loff_t *ppos)
625 struct dump_iter *i = file->private_data;
626 struct bch_fs *c = i->c;
627 struct btree_trans *trans;
635 seqmutex_lock(&c->btree_trans_lock);
636 list_for_each_entry(trans, &c->btree_trans_list, list) {
637 struct task_struct *task = READ_ONCE(trans->locking_wait.task);
639 if (!task || task->pid <= i->iter)
642 closure_get(&trans->ref);
643 seq = seqmutex_seq(&c->btree_trans_lock);
644 seqmutex_unlock(&c->btree_trans_lock);
648 closure_put(&trans->ref);
652 bch2_btree_trans_to_text(&i->buf, trans);
654 prt_printf(&i->buf, "backtrace:");
655 prt_newline(&i->buf);
656 printbuf_indent_add(&i->buf, 2);
657 bch2_prt_task_backtrace(&i->buf, task);
658 printbuf_indent_sub(&i->buf, 2);
659 prt_newline(&i->buf);
663 closure_put(&trans->ref);
665 if (!seqmutex_relock(&c->btree_trans_lock, seq))
668 seqmutex_unlock(&c->btree_trans_lock);
670 if (i->buf.allocation_failure)
676 return ret ?: i->ret;
679 static const struct file_operations btree_transactions_ops = {
680 .owner = THIS_MODULE,
681 .open = bch2_dump_open,
682 .release = bch2_dump_release,
683 .read = bch2_btree_transactions_read,
686 static ssize_t bch2_journal_pins_read(struct file *file, char __user *buf,
687 size_t size, loff_t *ppos)
689 struct dump_iter *i = file->private_data;
690 struct bch_fs *c = i->c;
706 done = bch2_journal_seq_pins_to_text(&i->buf, &c->journal, &i->iter);
710 if (i->buf.allocation_failure)
716 static const struct file_operations journal_pins_ops = {
717 .owner = THIS_MODULE,
718 .open = bch2_dump_open,
719 .release = bch2_dump_release,
720 .read = bch2_journal_pins_read,
723 static int lock_held_stats_open(struct inode *inode, struct file *file)
725 struct bch_fs *c = inode->i_private;
728 i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
736 file->private_data = i;
741 static int lock_held_stats_release(struct inode *inode, struct file *file)
743 struct dump_iter *i = file->private_data;
745 printbuf_exit(&i->buf);
751 static ssize_t lock_held_stats_read(struct file *file, char __user *buf,
752 size_t size, loff_t *ppos)
754 struct dump_iter *i = file->private_data;
755 struct bch_fs *c = i->c;
763 struct btree_transaction_stats *s = &c->btree_transaction_stats[i->iter];
772 if (i->iter == ARRAY_SIZE(bch2_btree_transaction_fns) ||
773 !bch2_btree_transaction_fns[i->iter])
776 prt_printf(&i->buf, "%s: ", bch2_btree_transaction_fns[i->iter]);
777 prt_newline(&i->buf);
778 printbuf_indent_add(&i->buf, 2);
780 mutex_lock(&s->lock);
782 prt_printf(&i->buf, "Max mem used: %u", s->max_mem);
783 prt_newline(&i->buf);
785 if (IS_ENABLED(CONFIG_BCACHEFS_LOCK_TIME_STATS)) {
786 prt_printf(&i->buf, "Lock hold times:");
787 prt_newline(&i->buf);
789 printbuf_indent_add(&i->buf, 2);
790 bch2_time_stats_to_text(&i->buf, &s->lock_hold_times);
791 printbuf_indent_sub(&i->buf, 2);
794 if (s->max_paths_text) {
795 prt_printf(&i->buf, "Maximum allocated btree paths (%u):", s->nr_max_paths);
796 prt_newline(&i->buf);
798 printbuf_indent_add(&i->buf, 2);
799 prt_str_indented(&i->buf, s->max_paths_text);
800 printbuf_indent_sub(&i->buf, 2);
803 mutex_unlock(&s->lock);
805 printbuf_indent_sub(&i->buf, 2);
806 prt_newline(&i->buf);
810 if (i->buf.allocation_failure)
816 static const struct file_operations lock_held_stats_op = {
817 .owner = THIS_MODULE,
818 .open = lock_held_stats_open,
819 .release = lock_held_stats_release,
820 .read = lock_held_stats_read,
823 static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf,
824 size_t size, loff_t *ppos)
826 struct dump_iter *i = file->private_data;
827 struct bch_fs *c = i->c;
828 struct btree_trans *trans;
839 seqmutex_lock(&c->btree_trans_lock);
840 list_for_each_entry(trans, &c->btree_trans_list, list) {
841 struct task_struct *task = READ_ONCE(trans->locking_wait.task);
843 if (!task || task->pid <= i->iter)
846 closure_get(&trans->ref);
847 seq = seqmutex_seq(&c->btree_trans_lock);
848 seqmutex_unlock(&c->btree_trans_lock);
852 closure_put(&trans->ref);
856 bch2_check_for_deadlock(trans, &i->buf);
860 closure_put(&trans->ref);
862 if (!seqmutex_relock(&c->btree_trans_lock, seq))
865 seqmutex_unlock(&c->btree_trans_lock);
867 if (i->buf.allocation_failure)
873 return ret ?: i->ret;
876 static const struct file_operations btree_deadlock_ops = {
877 .owner = THIS_MODULE,
878 .open = bch2_dump_open,
879 .release = bch2_dump_release,
880 .read = bch2_btree_deadlock_read,
883 void bch2_fs_debug_exit(struct bch_fs *c)
885 if (!IS_ERR_OR_NULL(c->fs_debug_dir))
886 debugfs_remove_recursive(c->fs_debug_dir);
889 void bch2_fs_debug_init(struct bch_fs *c)
891 struct btree_debug *bd;
894 if (IS_ERR_OR_NULL(bch_debug))
897 snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
898 c->fs_debug_dir = debugfs_create_dir(name, bch_debug);
899 if (IS_ERR_OR_NULL(c->fs_debug_dir))
902 debugfs_create_file("cached_btree_nodes", 0400, c->fs_debug_dir,
903 c->btree_debug, &cached_btree_nodes_ops);
905 debugfs_create_file("btree_transactions", 0400, c->fs_debug_dir,
906 c->btree_debug, &btree_transactions_ops);
908 debugfs_create_file("journal_pins", 0400, c->fs_debug_dir,
909 c->btree_debug, &journal_pins_ops);
911 debugfs_create_file("btree_transaction_stats", 0400, c->fs_debug_dir,
912 c, &lock_held_stats_op);
914 debugfs_create_file("btree_deadlock", 0400, c->fs_debug_dir,
915 c->btree_debug, &btree_deadlock_ops);
917 c->btree_debug_dir = debugfs_create_dir("btrees", c->fs_debug_dir);
918 if (IS_ERR_OR_NULL(c->btree_debug_dir))
921 for (bd = c->btree_debug;
922 bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
924 bd->id = bd - c->btree_debug;
925 debugfs_create_file(bch2_btree_id_str(bd->id),
926 0400, c->btree_debug_dir, bd,
929 snprintf(name, sizeof(name), "%s-formats",
930 bch2_btree_id_str(bd->id));
932 debugfs_create_file(name, 0400, c->btree_debug_dir, bd,
933 &btree_format_debug_ops);
935 snprintf(name, sizeof(name), "%s-bfloat-failed",
936 bch2_btree_id_str(bd->id));
938 debugfs_create_file(name, 0400, c->btree_debug_dir, bd,
939 &bfloat_failed_debug_ops);
945 void bch2_debug_exit(void)
947 if (!IS_ERR_OR_NULL(bch_debug))
948 debugfs_remove_recursive(bch_debug);
951 int __init bch2_debug_init(void)
955 bch_debug = debugfs_create_dir("bcachefs", NULL);