Re: [PATCH 7/7] nfsd: filecache: give disposal lock a unique class name.

[Chuck Lever <chuck.lever@oracle.com>]

On 1/26/25 8:20 PM, NeilBrown wrote:
> There are at least three locks in the kernel which are initialised as
> 
>    spin_Lock_init(&l->lock);
> 
> This makes them hard to differential in /proc/lock_stat.
> 
> For the lock in nfsd/filecache.c introduce a variable with a more
> descriptve name so we can:
> 
>    spin_lock_init(&nfsd_fcache_disposal->lock);
> 
> and easily identify this in /proc/lock_stat.
> 
> Signed-off-by: NeilBrown <neilb@suse.de>
> ---
>   fs/nfsd/filecache.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
> index eb95a53f806f..af95bc381753 100644
> --- a/fs/nfsd/filecache.c
> +++ b/fs/nfsd/filecache.c
> @@ -867,12 +867,13 @@ __nfsd_file_cache_purge(struct net *net)
>   static struct nfsd_fcache_disposal *
>   nfsd_alloc_fcache_disposal(void)
>   {
> -	struct nfsd_fcache_disposal *l;
> +	struct nfsd_fcache_disposal *l, *nfsd_fcache_disposal;
>   
>   	l = kmalloc(sizeof(*l), GFP_KERNEL);
>   	if (!l)
>   		return NULL;
> -	spin_lock_init(&l->lock);
> +	nfsd_fcache_disposal = l;
> +	spin_lock_init(&nfsd_fcache_disposal->lock);
>   	timer_setup(&l->timer, nfsd_file_gc_worker, 0);
>   	INIT_LIST_HEAD(&l->recent);
>   	INIT_LIST_HEAD(&l->older);

My concern was there would be multiple dynamically allocated locks
in order to make the locking fine-grained, but I guess that was a
mistaken assumption.

No objection to this approach.

-- 
Chuck Lever