Re: [PATCH 19/34] sunrpc: suppress warnings for unused procfs functions

[Jeff Layton]

On Wed, 2024-04-03 at 10:06 +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> There is a warning about unused variables when building with W=1 and no procfs:
> 
> net/sunrpc/cache.c:1660:30: error: 'cache_flush_proc_ops' defined but not used [-Werror=unused-const-variable=]
>  1660 | static const struct proc_ops cache_flush_proc_ops = {
>       |                              ^~~~~~~~~~~~~~~~~~~~
> net/sunrpc/cache.c:1622:30: error: 'content_proc_ops' defined but not used [-Werror=unused-const-variable=]
>  1622 | static const struct proc_ops content_proc_ops = {
>       |                              ^~~~~~~~~~~~~~~~
> net/sunrpc/cache.c:1598:30: error: 'cache_channel_proc_ops' defined but not used [-Werror=unused-const-variable=]
>  1598 | static const struct proc_ops cache_channel_proc_ops = {
>       |                              ^~~~~~~~~~~~~~~~~~~~~~
> 
> These are used inside of an #ifdef, so replacing that with an
> IS_ENABLED() check lets the compiler see how they are used while
> still dropping them during dead code elimination.
> 
> Fixes: dbf847ecb631 ("knfsd: allow cache_register to return error on failure")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>  net/sunrpc/cache.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
> 
> diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
> index 95ff74706104..ab3a57965dc0 100644
> --- a/net/sunrpc/cache.c
> +++ b/net/sunrpc/cache.c
> @@ -1673,12 +1673,14 @@ static void remove_cache_proc_entries(struct cache_detail *cd)
>  	}
>  }
>  
> -#ifdef CONFIG_PROC_FS
>  static int create_cache_proc_entries(struct cache_detail *cd, struct net *net)
>  {
>  	struct proc_dir_entry *p;
>  	struct sunrpc_net *sn;
>  
> +	if (!IS_ENABLED(CONFIG_PROC_FS))
> +		return 0;
> +
>  	sn = net_generic(net, sunrpc_net_id);
>  	cd->procfs = proc_mkdir(cd->name, sn->proc_net_rpc);
>  	if (cd->procfs == NULL)
> @@ -1706,12 +1708,6 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net)
>  	remove_cache_proc_entries(cd);
>  	return -ENOMEM;
>  }
> -#else /* CONFIG_PROC_FS */
> -static int create_cache_proc_entries(struct cache_detail *cd, struct net *net)
> -{
> -	return 0;
> -}
> -#endif
>  
>  void __init cache_initialize(void)
>  {

Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>