Re: [PATCH v4 06/12] dax: consistent variable naming for DAX entries

[Jan Kara]

On Thu 29-09-16 16:49:24, Ross Zwisler wrote:
> No functional change.
> 
> Consistently use the variable name 'entry' instead of 'ret' for DAX radix
> tree entries.  This was already happening in most of the code, so update
> get_unlocked_mapping_entry(), grab_mapping_entry() and
> dax_unlock_mapping_entry().
> 
> Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>

Looks good. You can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  fs/dax.c | 34 +++++++++++++++++-----------------
>  1 file changed, 17 insertions(+), 17 deletions(-)
> 
> diff --git a/fs/dax.c b/fs/dax.c
> index ac28cdf..baef586 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -357,7 +357,7 @@ static inline void *unlock_slot(struct address_space *mapping, void **slot)
>  static void *get_unlocked_mapping_entry(struct address_space *mapping,
>  					pgoff_t index, void ***slotp)
>  {
> -	void *ret, **slot;
> +	void *entry, **slot;
>  	struct wait_exceptional_entry_queue ewait;
>  	wait_queue_head_t *wq = dax_entry_waitqueue(mapping, index);
>  
> @@ -367,13 +367,13 @@ static void *get_unlocked_mapping_entry(struct address_space *mapping,
>  	ewait.key.index = index;
>  
>  	for (;;) {
> -		ret = __radix_tree_lookup(&mapping->page_tree, index, NULL,
> +		entry = __radix_tree_lookup(&mapping->page_tree, index, NULL,
>  					  &slot);
> -		if (!ret || !radix_tree_exceptional_entry(ret) ||
> +		if (!entry || !radix_tree_exceptional_entry(entry) ||
>  		    !slot_locked(mapping, slot)) {
>  			if (slotp)
>  				*slotp = slot;
> -			return ret;
> +			return entry;
>  		}
>  		prepare_to_wait_exclusive(wq, &ewait.wait,
>  					  TASK_UNINTERRUPTIBLE);
> @@ -396,13 +396,13 @@ static void *get_unlocked_mapping_entry(struct address_space *mapping,
>   */
>  static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index)
>  {
> -	void *ret, **slot;
> +	void *entry, **slot;
>  
>  restart:
>  	spin_lock_irq(&mapping->tree_lock);
> -	ret = get_unlocked_mapping_entry(mapping, index, &slot);
> +	entry = get_unlocked_mapping_entry(mapping, index, &slot);
>  	/* No entry for given index? Make sure radix tree is big enough. */
> -	if (!ret) {
> +	if (!entry) {
>  		int err;
>  
>  		spin_unlock_irq(&mapping->tree_lock);
> @@ -410,10 +410,10 @@ restart:
>  				mapping_gfp_mask(mapping) & ~__GFP_HIGHMEM);
>  		if (err)
>  			return ERR_PTR(err);
> -		ret = (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY |
> +		entry = (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY |
>  			       RADIX_DAX_ENTRY_LOCK);
>  		spin_lock_irq(&mapping->tree_lock);
> -		err = radix_tree_insert(&mapping->page_tree, index, ret);
> +		err = radix_tree_insert(&mapping->page_tree, index, entry);
>  		radix_tree_preload_end();
>  		if (err) {
>  			spin_unlock_irq(&mapping->tree_lock);
> @@ -425,11 +425,11 @@ restart:
>  		/* Good, we have inserted empty locked entry into the tree. */
>  		mapping->nrexceptional++;
>  		spin_unlock_irq(&mapping->tree_lock);
> -		return ret;
> +		return entry;
>  	}
>  	/* Normal page in radix tree? */
> -	if (!radix_tree_exceptional_entry(ret)) {
> -		struct page *page = ret;
> +	if (!radix_tree_exceptional_entry(entry)) {
> +		struct page *page = entry;
>  
>  		get_page(page);
>  		spin_unlock_irq(&mapping->tree_lock);
> @@ -442,9 +442,9 @@ restart:
>  		}
>  		return page;
>  	}
> -	ret = lock_slot(mapping, slot);
> +	entry = lock_slot(mapping, slot);
>  	spin_unlock_irq(&mapping->tree_lock);
> -	return ret;
> +	return entry;
>  }
>  
>  void dax_wake_mapping_entry_waiter(struct address_space *mapping,
> @@ -469,11 +469,11 @@ void dax_wake_mapping_entry_waiter(struct address_space *mapping,
>  
>  void dax_unlock_mapping_entry(struct address_space *mapping, pgoff_t index)
>  {
> -	void *ret, **slot;
> +	void *entry, **slot;
>  
>  	spin_lock_irq(&mapping->tree_lock);
> -	ret = __radix_tree_lookup(&mapping->page_tree, index, NULL, &slot);
> -	if (WARN_ON_ONCE(!ret || !radix_tree_exceptional_entry(ret) ||
> +	entry = __radix_tree_lookup(&mapping->page_tree, index, NULL, &slot);
> +	if (WARN_ON_ONCE(!entry || !radix_tree_exceptional_entry(entry) ||
>  			 !slot_locked(mapping, slot))) {
>  		spin_unlock_irq(&mapping->tree_lock);
>  		return;
> -- 
> 2.7.4
> 
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR