Re: [PATCH v2 3/3] smb/client: Use d_alloc_trylock() in cifs_prime_dcache()

[Paulo Alcantara <pc@manguebit.org>]

NeilBrown <neilb@ownmail.net> writes:

> @@ -77,36 +77,34 @@ cifs_prime_dcache(struct dentry *parent, struct qstr *name,
>  
>  	cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
>  
> -	dentry = try_lookup_noperm(name, parent);
> -	if (!dentry) {
> -		/*
> -		 * If we know that the inode will need to be revalidated
> -		 * immediately, then don't create a new dentry for it.
> -		 * We'll end up doing an on the wire call either way and
> -		 * this spares us an invalidation.
> -		 */
> -retry:
> -		if (posix) {
> -			switch (fattr->cf_mode & S_IFMT) {
> -			case S_IFLNK:
> -			case S_IFBLK:
> -			case S_IFCHR:
> -				reparse_need_reval = true;
> -				break;
> -			default:
> -				break;
> -			}
> -		} else if (fattr->cf_cifsattrs & ATTR_REPARSE_POINT) {
> +	/*
> +	 * If we know that the inode will need to be revalidated
> +	 * immediately, then don't create a new dentry for it.
> +	 * We'll end up doing an on the wire call either way and
> +	 * this spares us an invalidation.
> +	 */
> +	if (posix) {
> +		switch (fattr->cf_mode & S_IFMT) {
> +		case S_IFLNK:
> +		case S_IFBLK:
> +		case S_IFCHR:
>  			reparse_need_reval = true;
> +			break;
> +		default:
> +			break;
>  		}
> +	} else if (fattr->cf_cifsattrs & ATTR_REPARSE_POINT) {
> +		reparse_need_reval = true;
> +	}
>  
> -		if (reparse_need_reval ||
> -		    (fattr->cf_flags & CIFS_FATTR_NEED_REVAL))
> -			return;
> +retry:
> +	if (reparse_need_reval ||
> +	    (fattr->cf_flags & CIFS_FATTR_NEED_REVAL))
> +		dentry = try_lookup_noperm(name, parent);
> +	else
> +		dentry = d_alloc_trylock(parent, name);
>  
> -		dentry = d_alloc_parallel(parent, name);
> -	}
> -	if (IS_ERR(dentry))
> +	if (!dentry || IS_ERR(dentry))

nit: IS_ERR_OR_NULL(dentry)