Re: [PATCH V5 01/12] fs/xfs: Remove unnecessary initialization of i_rwsem

From: Ira Weiny <ira.weiny@intel.com>
To: linux-kernel@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
	"Darrick J. Wong" <darrick.wong@oracle.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Dave Chinner <david@fromorbit.com>,
	Christoph Hellwig <hch@lst.de>,
	"Theodore Y. Ts'o" <tytso@mit.edu>, Jan Kara <jack@suse.cz>,
	linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH V5 01/12] fs/xfs: Remove unnecessary initialization of i_rwsem
Date: Thu, 27 Feb 2020 09:25:49 -0800	[thread overview]
Message-ID: <20200227172549.GA6468@iweiny-DESK2.sc.intel.com> (raw)
In-Reply-To: <20200227052442.22524-2-ira.weiny@intel.com>

On Wed, Feb 26, 2020 at 09:24:31PM -0800, 'Ira Weiny' wrote:
> From: Ira Weiny <ira.weiny@intel.com>
> 
> xfs_reinit_inode() -> inode_init_always() already handles calling
> init_rwsem(i_rwsem).  Doing so again is unneeded.
> 
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Ok...  I'm going to blame exchange...

Dan just pointed out that I mist this response from Dave...

Saying this patch was wrong.

https://lore.kernel.org/lkml/20200221012625.GT10776@dread.disaster.area/

Sorry,  I need to read that email and look at it.

Ira

> 
> ---
> New for V4:
> 
> NOTE: This was found while ensuring the new i_aops_sem was properly
> handled.  It seems like this is a layering violation so I think it is
> worth cleaning up so as to not confuse others.
> ---
>  fs/xfs/xfs_icache.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
> index 8dc2e5414276..836a1f09be03 100644
> --- a/fs/xfs/xfs_icache.c
> +++ b/fs/xfs/xfs_icache.c
> @@ -419,6 +419,7 @@ xfs_iget_cache_hit(
>  		spin_unlock(&ip->i_flags_lock);
>  		rcu_read_unlock();
>  
> +		ASSERT(!rwsem_is_locked(&inode->i_rwsem));
>  		error = xfs_reinit_inode(mp, inode);
>  		if (error) {
>  			bool wake;
> @@ -452,9 +453,6 @@ xfs_iget_cache_hit(
>  		ip->i_sick = 0;
>  		ip->i_checked = 0;
>  
> -		ASSERT(!rwsem_is_locked(&inode->i_rwsem));
> -		init_rwsem(&inode->i_rwsem);
> -
>  		spin_unlock(&ip->i_flags_lock);
>  		spin_unlock(&pag->pag_ici_lock);
>  	} else {
> -- 
> 2.21.0
> 