diff options
| -rw-r--r-- | fs/btrfs/transaction.c | 55 | ||||
| -rw-r--r-- | fs/btrfs/transaction.h | 31 |
2 files changed, 65 insertions, 21 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index cf8706c..fd319b2 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -51,17 +51,41 @@ static noinline void switch_commit_root(struct btrfs_root *root) } static inline int can_join_transaction(struct btrfs_transaction *trans, - int type) + unsigned int type) { return !(trans->in_commit && - type != TRANS_JOIN && - type != TRANS_JOIN_NOLOCK); + (type & TRANS_EXTWRITERS)); +} + +static inline void extwriter_counter_inc(struct btrfs_transaction *trans, + unsigned int type) +{ + if (type & TRANS_EXTWRITERS) + atomic_inc(&trans->num_extwriters); +} + +static inline void extwriter_counter_dec(struct btrfs_transaction *trans, + unsigned int type) +{ + if (type & TRANS_EXTWRITERS) + atomic_dec(&trans->num_extwriters); +} + +static inline void extwriter_counter_init(struct btrfs_transaction *trans, + unsigned int type) +{ + atomic_set(&trans->num_extwriters, ((type & TRANS_EXTWRITERS) ? 1 : 0)); +} + +static inline int extwriter_counter_read(struct btrfs_transaction *trans) +{ + return atomic_read(&trans->num_extwriters); } /* * either allocate a new transaction or hop into the existing one */ -static noinline int join_transaction(struct btrfs_root *root, int type) +static noinline int join_transaction(struct btrfs_root *root, unsigned int type) { struct btrfs_transaction *cur_trans; struct btrfs_fs_info *fs_info = root->fs_info; @@ -99,6 +123,7 @@ loop: } atomic_inc(&cur_trans->use_count); atomic_inc(&cur_trans->num_writers); + extwriter_counter_inc(cur_trans, type); cur_trans->num_joined++; spin_unlock(&fs_info->trans_lock); return 0; @@ -131,6 +156,7 @@ loop: } atomic_set(&cur_trans->num_writers, 1); + extwriter_counter_init(cur_trans, type); cur_trans->num_joined = 0; init_waitqueue_head(&cur_trans->writer_wait); init_waitqueue_head(&cur_trans->commit_wait); @@ -307,7 +333,7 @@ static int may_wait_transaction(struct btrfs_root *root, int type) } static struct btrfs_trans_handle * -start_transaction(struct btrfs_root *root, u64 num_items, int type, +start_transaction(struct btrfs_root *root, u64 num_items, unsigned int type, enum btrfs_reserve_flush_enum flush) { struct btrfs_trans_handle *h; @@ -320,7 +346,7 @@ start_transaction(struct btrfs_root *root, u64 num_items, int type, return ERR_PTR(-EROFS); if (current->journal_info) { - WARN_ON(type != TRANS_JOIN && type != TRANS_JOIN_NOLOCK); + WARN_ON(type & TRANS_EXTWRITERS); h = current->journal_info; h->use_count++; WARN_ON(h->use_count > 2); @@ -366,7 +392,7 @@ again: * If we are ATTACH, it means we just want to catch the current * transaction and commit it, so we needn't do sb_start_intwrite(). */ - if (type < TRANS_JOIN_NOLOCK) + if (type & __TRANS_FREEZABLE) sb_start_intwrite(root->fs_info->sb); if (may_wait_transaction(root, type)) @@ -429,7 +455,7 @@ got_it: return h; join_fail: - if (type < TRANS_JOIN_NOLOCK) + if (type & __TRANS_FREEZABLE) sb_end_intwrite(root->fs_info->sb); kmem_cache_free(btrfs_trans_handle_cachep, h); alloc_fail: @@ -677,12 +703,13 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, } } - if (trans->type < TRANS_JOIN_NOLOCK) + if (trans->type & __TRANS_FREEZABLE) sb_end_intwrite(root->fs_info->sb); WARN_ON(cur_trans != info->running_transaction); WARN_ON(atomic_read(&cur_trans->num_writers) < 1); atomic_dec(&cur_trans->num_writers); + extwriter_counter_dec(cur_trans, trans->type); smp_mb(); if (waitqueue_active(&cur_trans->writer_wait)) @@ -1625,6 +1652,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, spin_unlock(&root->fs_info->trans_lock); } + extwriter_counter_dec(cur_trans, trans->type); + if (!btrfs_test_opt(root, SSD) && (now < cur_trans->start_time || now - cur_trans->start_time < 1)) should_grow = 1; @@ -1641,13 +1670,13 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, prepare_to_wait(&cur_trans->writer_wait, &wait, TASK_UNINTERRUPTIBLE); - if (atomic_read(&cur_trans->num_writers) > 1) - schedule_timeout(MAX_SCHEDULE_TIMEOUT); + if (extwriter_counter_read(cur_trans) > 0) + schedule(); else if (should_grow) schedule_timeout(1); finish_wait(&cur_trans->writer_wait, &wait); - } while (atomic_read(&cur_trans->num_writers) > 1 || + } while (extwriter_counter_read(cur_trans) > 0 || (should_grow && cur_trans->num_joined != joined)); ret = btrfs_flush_all_pending_stuffs(trans, root); @@ -1831,7 +1860,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, put_transaction(cur_trans); put_transaction(cur_trans); - if (trans->type < TRANS_JOIN_NOLOCK) + if (trans->type & __TRANS_FREEZABLE) sb_end_intwrite(root->fs_info->sb); trace_btrfs_transaction_commit(root); diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index 24c9733..5cc77b0 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -25,6 +25,12 @@ struct btrfs_transaction { u64 transid; /* + * total external writers(USERSPACE/START/ATTACH) in this + * transaction, it must be zero before the transaction is + * being committed + */ + atomic_t num_extwriters; + /* * total writers in this transaction, it must be zero before the * transaction can end */ @@ -48,13 +54,22 @@ struct btrfs_transaction { int aborted; }; -enum btrfs_trans_type { - TRANS_START, - TRANS_JOIN, - TRANS_USERSPACE, - TRANS_JOIN_NOLOCK, - TRANS_ATTACH, -}; +#define __TRANS_FREEZABLE (1U << 0) + +#define __TRANS_USERSPACE (1U << 8) +#define __TRANS_START (1U << 9) +#define __TRANS_ATTACH (1U << 10) +#define __TRANS_JOIN (1U << 11) +#define __TRANS_JOIN_NOLOCK (1U << 12) + +#define TRANS_USERSPACE (__TRANS_USERSPACE | __TRANS_FREEZABLE) +#define TRANS_START (__TRANS_START | __TRANS_FREEZABLE) +#define TRANS_ATTACH (__TRANS_ATTACH) +#define TRANS_JOIN (__TRANS_JOIN | __TRANS_FREEZABLE) +#define TRANS_JOIN_NOLOCK (__TRANS_JOIN_NOLOCK) + +#define TRANS_EXTWRITERS (__TRANS_USERSPACE | __TRANS_START | \ + __TRANS_ATTACH) struct btrfs_trans_handle { u64 transid; @@ -70,7 +85,7 @@ struct btrfs_trans_handle { short aborted; short adding_csums; bool allocating_chunk; - enum btrfs_trans_type type; + unsigned int type; /* * this root is only needed to validate that the root passed to * start_transaction is the same as the one passed to end_transaction. |