linux-kernel - Re: [PATCH] fs/dcache.c: revamped to use a more straightforward and efficient way to operate

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20071001172519.GC4178@atrey.karlin.mff.cuni.cz>
Date:	Mon, 1 Oct 2007 19:25:19 +0200
From:	Jan Kara <jack@...e.cz>
To:	Denis Cheng <crquan@...il.com>
Cc:	Alexander Viro <viro@...iv.linux.org.uk>,
	linux-kernel@...r.kernel.org, cr_quan@....com
Subject: Re: [PATCH] fs/dcache.c: revamped to use a more straightforward and efficient way to operate

  Hello,

  thanks for the patch. I have a few comments to it:
1) the patch should have a description in it, not only an email subject
2) usually, if an 'if' branch ends with return, as is the case in your
   patch, we don't use 'else' for the other branch...

BTW: I'm not convinced your code would be faster (or slower) than the
original one but you're right it will be easier to read...

								Honza

> Signed-off-by: Denis Cheng <crquan@...il.com>
> ---
>  fs/dcache.c |   39 ++++++++++++++++++---------------------
>  1 files changed, 18 insertions(+), 21 deletions(-)
> 
> diff --git a/fs/dcache.c b/fs/dcache.c
> index 678d39d..05ed44a 100644
> --- a/fs/dcache.c
> +++ b/fs/dcache.c
> @@ -1138,29 +1138,26 @@ struct dentry * d_alloc_anon(struct inode *inode)
>  	
>  	spin_lock(&dcache_lock);
>  	res = __d_find_alias(inode, 0);
> -	if (!res) {
> -		/* attach a disconnected dentry */
> -		res = tmp;
> -		tmp = NULL;
> -		spin_lock(&res->d_lock);
> -		res->d_sb = inode->i_sb;
> -		res->d_parent = res;
> -		res->d_inode = inode;
> -		res->d_flags |= DCACHE_DISCONNECTED;
> -		res->d_flags &= ~DCACHE_UNHASHED;
> -		list_add(&res->d_alias, &inode->i_dentry);
> -		hlist_add_head(&res->d_hash, &inode->i_sb->s_anon);
> -		spin_unlock(&res->d_lock);
> -
> -		inode = NULL; /* don't drop reference */
> -	}
> -	spin_unlock(&dcache_lock);
> -
> -	if (inode)
> +	if (unlikely(res)) {
> +		spin_unlock(&dcache_lock);
>  		iput(inode);
> -	if (tmp)
>  		dput(tmp);
> -	return res;
> +		return res;
> +	} else {
> +		/* attach a disconnected dentry */
> +		spin_lock(&tmp->d_lock);
> +		tmp->d_sb = inode->i_sb;
> +		tmp->d_parent = tmp;
> +		tmp->d_inode = inode;
> +		tmp->d_flags |= DCACHE_DISCONNECTED;
> +		tmp->d_flags &= ~DCACHE_UNHASHED;
> +		list_add(&tmp->d_alias, &inode->i_dentry);
> +		hlist_add_head(&tmp->d_hash, &inode->i_sb->s_anon);
> +		spin_unlock(&tmp->d_lock);
> +
> +		spin_unlock(&dcache_lock);
> +		return tmp;
> +	}
>  }
>  
>  
> -- 
> 1.5.3.2
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
-- 
Jan Kara <jack@...e.cz>
SuSE CR Labs
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/