From 34eb2a524997e5cd7117569b1fda925516adf6ac Mon Sep 17 00:00:00 2001 From: Zhaolei Date: Mon, 17 Aug 2015 18:44:45 +0800 Subject: [PATCH] btrfs: Remove useless condition in start_log_trans() Dan Carpenter reported a smatch warning for start_log_trans(): fs/btrfs/tree-log.c:178 start_log_trans() warn: we tested 'root->log_root' before and it was 'false' fs/btrfs/tree-log.c 147 if (root->log_root) { We test "root->log_root" here. ... Reason: Condition of: fs/btrfs/tree-log.c:178: if (!root->log_root) { is not necessary after commit: 7237f1833 It caused a smatch warning, and no functionally error. Fix: Deleting above condition will make smatch shut up, but a better way is to do cleanup for start_log_trans() to remove duplicated code and make code more readable. Reported-by: Dan Carpenter Signed-off-by: Zhao Lei Signed-off-by: Chris Mason --- fs/btrfs/tree-log.c | 43 +++++++++++++++++-------------------------- 1 file changed, 17 insertions(+), 26 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 9314adeba946..2e65e8e73844 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -140,55 +140,46 @@ static int start_log_trans(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_log_ctx *ctx) { - int index; - int ret; + int ret = 0; mutex_lock(&root->log_mutex); + if (root->log_root) { if (btrfs_need_log_full_commit(root->fs_info, trans)) { ret = -EAGAIN; goto out; } + if (!root->log_start_pid) { - root->log_start_pid = current->pid; clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); + root->log_start_pid = current->pid; } else if (root->log_start_pid != current->pid) { set_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); } + } else { + mutex_lock(&root->fs_info->tree_log_mutex); + if (!root->fs_info->log_root_tree) + ret = btrfs_init_log_root_tree(trans, root->fs_info); + mutex_unlock(&root->fs_info->tree_log_mutex); + if (ret) + goto out; - atomic_inc(&root->log_batch); - atomic_inc(&root->log_writers); - if (ctx) { - index = root->log_transid % 2; - list_add_tail(&ctx->list, &root->log_ctxs[index]); - ctx->log_transid = root->log_transid; - } - mutex_unlock(&root->log_mutex); - return 0; - } - - ret = 0; - mutex_lock(&root->fs_info->tree_log_mutex); - if (!root->fs_info->log_root_tree) - ret = btrfs_init_log_root_tree(trans, root->fs_info); - mutex_unlock(&root->fs_info->tree_log_mutex); - if (ret) - goto out; - - if (!root->log_root) { ret = btrfs_add_log_tree(trans, root); if (ret) goto out; + + clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); + root->log_start_pid = current->pid; } - clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); - root->log_start_pid = current->pid; + atomic_inc(&root->log_batch); atomic_inc(&root->log_writers); if (ctx) { - index = root->log_transid % 2; + int index = root->log_transid % 2; list_add_tail(&ctx->list, &root->log_ctxs[index]); ctx->log_transid = root->log_transid; } + out: mutex_unlock(&root->log_mutex); return ret; -- 2.20.1