Re: [PATCH 6/9] nfsd: fix empty-body warning in nfs4state.c

[Joe Perches <joe@perches.com>]

On Sat, 2020-04-18 at 14:45 -0400, Chuck Lever wrote:
> > On Apr 18, 2020, at 2:41 PM, Randy Dunlap <rdunlap@infradead.org> wrote:
> > 
> > Fix gcc empty-body warning when -Wextra is used:
> > 
> > ../fs/nfsd/nfs4state.c:3898:3: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
> > 
> > Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
> > Cc: Linus Torvalds <torvalds@linux-foundation.org>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: "J. Bruce Fields" <bfields@fieldses.org>
> > Cc: Chuck Lever <chuck.lever@oracle.com>
> > Cc: linux-nfs@vger.kernel.org
> 
> I have a patch in my queue that addresses this particular warning,
> but your change works for me too.
> 
> Acked-by: Chuck Lever <chuck.lever@oracle.com>
> 
> Unless Bruce objects.
> 
> 
> > ---
> > fs/nfsd/nfs4state.c |    3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > --- linux-next-20200417.orig/fs/nfsd/nfs4state.c
> > +++ linux-next-20200417/fs/nfsd/nfs4state.c
> > @@ -34,6 +34,7 @@
> > 
> > #include <linux/file.h>
> > #include <linux/fs.h>
> > +#include <linux/kernel.h>
> > #include <linux/slab.h>
> > #include <linux/namei.h>
> > #include <linux/swap.h>
> > @@ -3895,7 +3896,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp
> > 		copy_clid(new, conf);
> > 		gen_confirm(new, nn);
> > 	} else /* case 4 (new client) or cases 2, 3 (client reboot): */
> > -		;
> > +		do_empty();
> > 	new->cl_minorversion = 0;
> > 	gen_callback(new, setclid, rqstp);
> > 	add_to_unconfirmed(new);

This empty else seems silly and could likely be better handled by
a comment above the first if, something like:

	/* for now only handle case 1: probable callback update */
	if (conf && same_verf(&conf->cl_verifier, &clverifier)) {
		copy_clid(new, conf);
		gen_confirm(new, nn);
	}

with no else use.