diff options
author | Coly Li <colyli@suse.de> | 2020-03-22 09:03:01 +0300 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2020-03-22 19:06:57 +0300 |
commit | 8e7102273f597dbb38af43da874f8c123f8e6dbe (patch) | |
tree | 8f03c2d6e9998cae3fa1172d93dc556d5cca50f4 /drivers/md/bcache/btree.h | |
parent | feac1a70b806373d076a95b739c4feeceb21e814 (diff) | |
download | linux-8e7102273f597dbb38af43da874f8c123f8e6dbe.tar.xz |
bcache: make bch_btree_check() to be multithreaded
When registering a cache device, bch_btree_check() is called to check
all btree nodes, to make sure the btree is consistent and not
corrupted.
bch_btree_check() is recursively executed in a single thread, when there
are a lot of data cached and the btree is huge, it may take very long
time to check all the btree nodes. In my testing, I observed it took
around 50 minutes to finish bch_btree_check().
When checking the bcache btree nodes, the cache set is not running yet,
and indeed the whole tree is in read-only state, it is safe to create
multiple threads to check the btree in parallel.
This patch tries to create multiple threads, and each thread tries to
one-by-one check the sub-tree indexed by a key from the btree root node.
The parallel thread number depends on how many keys in the btree root
node. At most BCH_BTR_CHKTHREAD_MAX (64) threads can be created, but in
practice is should be min(cpu-number/2, root-node-keys-number).
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md/bcache/btree.h')
-rw-r--r-- | drivers/md/bcache/btree.h | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/md/bcache/btree.h b/drivers/md/bcache/btree.h index 19e30266070a..7c884f278da8 100644 --- a/drivers/md/bcache/btree.h +++ b/drivers/md/bcache/btree.h @@ -145,6 +145,9 @@ struct btree { struct bio *bio; }; + + + #define BTREE_FLAG(flag) \ static inline bool btree_node_ ## flag(struct btree *b) \ { return test_bit(BTREE_NODE_ ## flag, &b->flags); } \ @@ -216,6 +219,25 @@ struct btree_op { unsigned int insert_collision:1; }; +struct btree_check_state; +struct btree_check_info { + struct btree_check_state *state; + struct task_struct *thread; + int result; +}; + +#define BCH_BTR_CHKTHREAD_MAX 64 +struct btree_check_state { + struct cache_set *c; + int total_threads; + int key_idx; + spinlock_t idx_lock; + atomic_t started; + atomic_t enough; + wait_queue_head_t wait; + struct btree_check_info infos[BCH_BTR_CHKTHREAD_MAX]; +}; + static inline void bch_btree_op_init(struct btree_op *op, int write_lock_level) { memset(op, 0, sizeof(struct btree_op)); |