Re: [PATCH 1/9] sunrpc: don't keep expired entries in the auth caches.

["J. Bruce Fields" <bfields@fieldses.org>]

On Wed, Feb 03, 2010 at 05:31:31PM +1100, NeilBrown wrote:
> currently expired entries remain in the auth caches as long
> as there is a reference.
> This was needed long ago when the auth_domain cache used the same
> cache infrastructure.  But since that (being a very different sort
> of cache) was separated, this test is no longer needed.
> 
> So remove the test on refcnt and tidy up the surrounding code.
> 
> This allows the cache_dequeue call (which needed to be there to
> drop a potentially awkward reference) can be moved outside of the
> spinlock which is a better place for it.

Applied, thanks.--b.

> 
> Signed-off-by: NeilBrown <neilb@suse.de>
> ---
>  net/sunrpc/cache.c |   13 +++++--------
>  1 files changed, 5 insertions(+), 8 deletions(-)
> 
> diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
> index 39bddba..83592e0 100644
> --- a/net/sunrpc/cache.c
> +++ b/net/sunrpc/cache.c
> @@ -397,31 +397,28 @@ static int cache_clean(void)
>  		/* Ok, now to clean this strand */
>  
>  		cp = & current_detail->hash_table[current_index];
> -		ch = *cp;
> -		for (; ch; cp= & ch->next, ch= *cp) {
> +		for (ch = *cp ; ch ; cp = & ch->next, ch = *cp) {
>  			if (current_detail->nextcheck > ch->expiry_time)
>  				current_detail->nextcheck = ch->expiry_time+1;
>  			if (ch->expiry_time >= get_seconds() &&
>  			    ch->last_refresh >= current_detail->flush_time)
>  				continue;
> -			if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
> -				cache_dequeue(current_detail, ch);
>  
> -			if (atomic_read(&ch->ref.refcount) == 1)
> -				break;
> -		}
> -		if (ch) {
>  			*cp = ch->next;
>  			ch->next = NULL;
>  			current_detail->entries--;
>  			rv = 1;
> +			break;
>  		}
> +
>  		write_unlock(&current_detail->hash_lock);
>  		d = current_detail;
>  		if (!ch)
>  			current_index ++;
>  		spin_unlock(&cache_list_lock);
>  		if (ch) {
> +			if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
> +				cache_dequeue(current_detail, ch);
>  			cache_revisit_request(ch);
>  			cache_put(ch, d);
>  		}
> 
>