[lustre-devel] [PATCH 14/21] lustre: make ccc_users in cl_client_cache a refcount_t

[James Simmons]

> As this is used as a refcount, it should be declared
> as one.

Reviewed-by: James Simmons <jsimmons at infradead.org>
 
> Signed-off-by: NeilBrown <neilb at suse.com>
> ---
>  drivers/staging/lustre/lustre/include/cl_object.h |    2 +-
>  drivers/staging/lustre/lustre/llite/lproc_llite.c |    2 +-
>  drivers/staging/lustre/lustre/obdclass/cl_page.c  |    6 +++---
>  drivers/staging/lustre/lustre/osc/osc_page.c      |    4 ++--
>  drivers/staging/lustre/lustre/osc/osc_request.c   |    2 +-
>  5 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/staging/lustre/lustre/include/cl_object.h b/drivers/staging/lustre/lustre/include/cl_object.h
> index c2273c3100e8..05be85306663 100644
> --- a/drivers/staging/lustre/lustre/include/cl_object.h
> +++ b/drivers/staging/lustre/lustre/include/cl_object.h
> @@ -2181,7 +2181,7 @@ struct cl_client_cache {
>  	 * # of client cache refcount
>  	 * # of users (OSCs) + 2 (held by llite and lov)
>  	 */
> -	atomic_t		ccc_users;
> +	refcount_t		ccc_users;
>  	/**
>  	 * # of threads are doing shrinking
>  	 */
> diff --git a/drivers/staging/lustre/lustre/llite/lproc_llite.c b/drivers/staging/lustre/lustre/llite/lproc_llite.c
> index 001bed90f4da..8215296dc15d 100644
> --- a/drivers/staging/lustre/lustre/llite/lproc_llite.c
> +++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c
> @@ -467,7 +467,7 @@ static int ll_max_cached_mb_seq_show(struct seq_file *m, void *v)
>  		   "used_mb: %ld\n"
>  		   "unused_mb: %ld\n"
>  		   "reclaim_count: %u\n",
> -		   atomic_read(&cache->ccc_users),
> +		   refcount_read(&cache->ccc_users),
>  		   max_cached_mb,
>  		   max_cached_mb - unused_mb,
>  		   unused_mb,
> diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c
> index f0ece7e9a4ac..7dcd3aff229f 100644
> --- a/drivers/staging/lustre/lustre/obdclass/cl_page.c
> +++ b/drivers/staging/lustre/lustre/obdclass/cl_page.c
> @@ -960,7 +960,7 @@ struct cl_client_cache *cl_cache_init(unsigned long lru_page_max)
>  		return NULL;
>  
>  	/* Initialize cache data */
> -	atomic_set(&cache->ccc_users, 1);
> +	refcount_set(&cache->ccc_users, 1);
>  	cache->ccc_lru_max = lru_page_max;
>  	atomic_long_set(&cache->ccc_lru_left, lru_page_max);
>  	spin_lock_init(&cache->ccc_lru_lock);
> @@ -978,7 +978,7 @@ EXPORT_SYMBOL(cl_cache_init);
>   */
>  void cl_cache_incref(struct cl_client_cache *cache)
>  {
> -	atomic_inc(&cache->ccc_users);
> +	refcount_inc(&cache->ccc_users);
>  }
>  EXPORT_SYMBOL(cl_cache_incref);
>  
> @@ -989,7 +989,7 @@ EXPORT_SYMBOL(cl_cache_incref);
>   */
>  void cl_cache_decref(struct cl_client_cache *cache)
>  {
> -	if (atomic_dec_and_test(&cache->ccc_users))
> +	if (refcount_dec_and_test(&cache->ccc_users))
>  		kfree(cache);
>  }
>  EXPORT_SYMBOL(cl_cache_decref);
> diff --git a/drivers/staging/lustre/lustre/osc/osc_page.c b/drivers/staging/lustre/lustre/osc/osc_page.c
> index 135bfe5e1b37..ce911b82512d 100644
> --- a/drivers/staging/lustre/lustre/osc/osc_page.c
> +++ b/drivers/staging/lustre/lustre/osc/osc_page.c
> @@ -346,7 +346,7 @@ static int osc_cache_too_much(struct client_obd *cli)
>  	long pages = atomic_long_read(&cli->cl_lru_in_list);
>  	unsigned long budget;
>  
> -	budget = cache->ccc_lru_max / (atomic_read(&cache->ccc_users) - 2);
> +	budget = cache->ccc_lru_max / (refcount_read(&cache->ccc_users) - 2);
>  
>  	/* if it's going to run out LRU slots, we should free some, but not
>  	 * too much to maintain fairness among OSCs.
> @@ -707,7 +707,7 @@ static long osc_lru_reclaim(struct client_obd *cli, unsigned long npages)
>  	cache->ccc_lru_shrinkers++;
>  	list_move_tail(&cli->cl_lru_osc, &cache->ccc_lru);
>  
> -	max_scans = atomic_read(&cache->ccc_users) - 2;
> +	max_scans = refcount_read(&cache->ccc_users) - 2;
>  	while (--max_scans > 0 &&
>  	       (cli = list_first_entry_or_null(&cache->ccc_lru,
>  					       struct client_obd,
> diff --git a/drivers/staging/lustre/lustre/osc/osc_request.c b/drivers/staging/lustre/lustre/osc/osc_request.c
> index 9e72fa8f68b3..0dfc506f6d01 100644
> --- a/drivers/staging/lustre/lustre/osc/osc_request.c
> +++ b/drivers/staging/lustre/lustre/osc/osc_request.c
> @@ -2959,7 +2959,7 @@ static int osc_cleanup(struct obd_device *obd)
>  
>  	/* lru cleanup */
>  	if (cli->cl_cache) {
> -		LASSERT(atomic_read(&cli->cl_cache->ccc_users) > 0);
> +		LASSERT(refcount_read(&cli->cl_cache->ccc_users) > 0);
>  		spin_lock(&cli->cl_cache->ccc_lru_lock);
>  		list_del_init(&cli->cl_lru_osc);
>  		spin_unlock(&cli->cl_cache->ccc_lru_lock);
> 
> 
>