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* [PATCH] - [7/15] - remove defconfig ptr comparisons to 0 - fs/lockd
@ 2007-11-14  2:05 Joe Perches
  2007-11-14  2:40 ` Neil Brown
  0 siblings, 1 reply; 4+ messages in thread
From: Joe Perches @ 2007-11-14  2:05 UTC (permalink / raw)
  To: linux-kernel; +Cc: Linus Torvalds, Trond Myklebust, Neil Brown, nfs

Remove defconfig ptr comparison to 0

Remove sparse warning: Using plain integer as NULL pointer

Signed-off-by: Joe Perches <joe@perches.com>

---

diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c
index 068886d..98548ad 100644
--- a/fs/lockd/svcshare.c
+++ b/fs/lockd/svcshare.c
@@ -71,7 +71,7 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
 	struct nlm_share	*share, **shpp;
 	struct xdr_netobj	*oh = &argp->lock.oh;
 
-	for (shpp = &file->f_shares; (share = *shpp) != 0; shpp = &share->s_next) {
+	for (shpp = &file->f_shares; (share = *shpp); shpp = &share->s_next) {
 		if (share->s_host == host && nlm_cmp_owner(share, oh)) {
 			*shpp = share->s_next;
 			kfree(share);



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] - [7/15] - remove defconfig ptr comparisons to 0 - fs/lockd
  2007-11-14  2:05 [PATCH] - [7/15] - remove defconfig ptr comparisons to 0 - fs/lockd Joe Perches
@ 2007-11-14  2:40 ` Neil Brown
  2007-11-14  4:45   ` Trond Myklebust
  0 siblings, 1 reply; 4+ messages in thread
From: Neil Brown @ 2007-11-14  2:40 UTC (permalink / raw)
  To: Joe Perches; +Cc: linux-kernel, Linus Torvalds, Trond Myklebust, nfs

On Tuesday November 13, joe@perches.com wrote:
> Remove defconfig ptr comparison to 0
> 
> Remove sparse warning: Using plain integer as NULL pointer
> 
> Signed-off-by: Joe Perches <joe@perches.com>
> 
> ---
> 
> diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c
> index 068886d..98548ad 100644
> --- a/fs/lockd/svcshare.c
> +++ b/fs/lockd/svcshare.c
> @@ -71,7 +71,7 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
>  	struct nlm_share	*share, **shpp;
>  	struct xdr_netobj	*oh = &argp->lock.oh;
>  
> -	for (shpp = &file->f_shares; (share = *shpp) != 0; shpp = &share->s_next) {
> +	for (shpp = &file->f_shares; (share = *shpp); shpp = &share->s_next) {
>  		if (share->s_host == host && nlm_cmp_owner(share, oh)) {
>  			*shpp = share->s_next;
>  			kfree(share);
> 

I particularly disagree with this change as it now looked like it
could be an '==' comparison that was mistyped.  Making it 
        ....; (share = *shpp) != NULL; ....

makes the intent clear.

NeilBrown

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] - [7/15] - remove defconfig ptr comparisons to 0 - fs/lockd
  2007-11-14  2:40 ` Neil Brown
@ 2007-11-14  4:45   ` Trond Myklebust
  2007-11-14 17:50     ` Trond Myklebust
  0 siblings, 1 reply; 4+ messages in thread
From: Trond Myklebust @ 2007-11-14  4:45 UTC (permalink / raw)
  To: Neil Brown; +Cc: Joe Perches, linux-kernel, Linus Torvalds, nfs


On Wed, 2007-11-14 at 13:40 +1100, Neil Brown wrote:
> On Tuesday November 13, joe@perches.com wrote:
> > Remove defconfig ptr comparison to 0
> > 
> > Remove sparse warning: Using plain integer as NULL pointer
> > 
> > Signed-off-by: Joe Perches <joe@perches.com>
> > 
> > ---
> > 
> > diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c
> > index 068886d..98548ad 100644
> > --- a/fs/lockd/svcshare.c
> > +++ b/fs/lockd/svcshare.c
> > @@ -71,7 +71,7 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
> >  	struct nlm_share	*share, **shpp;
> >  	struct xdr_netobj	*oh = &argp->lock.oh;
> >  
> > -	for (shpp = &file->f_shares; (share = *shpp) != 0; shpp = &share->s_next) {
> > +	for (shpp = &file->f_shares; (share = *shpp); shpp = &share->s_next) {
> >  		if (share->s_host == host && nlm_cmp_owner(share, oh)) {
> >  			*shpp = share->s_next;
> >  			kfree(share);
> > 
> 
> I particularly disagree with this change as it now looked like it
> could be an '==' comparison that was mistyped.  Making it 
>         ....; (share = *shpp) != NULL; ....

There would also be the minor fact that the original test is being
inverted in this 'fix'. An accurate fix should at the very least be
   !(share = *shpp).

> makes the intent clear.

It would be a lot cleaner just to pull the entire assignment out of the
for() statement. IOW:

	for (shpp = &file->f_shares; *shpp != NULL; shpp = &(*shpp)->s_next) {
		struct nlm_share *share = *shpp;




^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] - [7/15] - remove defconfig ptr comparisons to 0 - fs/lockd
  2007-11-14  4:45   ` Trond Myklebust
@ 2007-11-14 17:50     ` Trond Myklebust
  0 siblings, 0 replies; 4+ messages in thread
From: Trond Myklebust @ 2007-11-14 17:50 UTC (permalink / raw)
  To: Neil Brown; +Cc: Joe Perches, linux-kernel, Linus Torvalds, nfs


On Tue, 2007-11-13 at 23:45 -0500, Trond Myklebust wrote:
> On Wed, 2007-11-14 at 13:40 +1100, Neil Brown wrote:
> > On Tuesday November 13, joe@perches.com wrote:
> > > Remove defconfig ptr comparison to 0
> > > 
> > > Remove sparse warning: Using plain integer as NULL pointer
> > > 
> > > Signed-off-by: Joe Perches <joe@perches.com>
> > > 
> > > ---
> > > 
> > > diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c
> > > index 068886d..98548ad 100644
> > > --- a/fs/lockd/svcshare.c
> > > +++ b/fs/lockd/svcshare.c
> > > @@ -71,7 +71,7 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
> > >  	struct nlm_share	*share, **shpp;
> > >  	struct xdr_netobj	*oh = &argp->lock.oh;
> > >  
> > > -	for (shpp = &file->f_shares; (share = *shpp) != 0; shpp = &share->s_next) {
> > > +	for (shpp = &file->f_shares; (share = *shpp); shpp = &share->s_next) {
> > >  		if (share->s_host == host && nlm_cmp_owner(share, oh)) {
> > >  			*shpp = share->s_next;
> > >  			kfree(share);
> > > 
> > 
> > I particularly disagree with this change as it now looked like it
> > could be an '==' comparison that was mistyped.  Making it 
> >         ....; (share = *shpp) != NULL; ....
> 
> There would also be the minor fact that the original test is being
> inverted in this 'fix'. An accurate fix should at the very least be
>    !(share = *shpp).

Apologies to Joe. I must have been tired when I typed the above. However
I'm still NACKing the patch: removing the '!= 0' altogether reduces code
legibility rather than improving it, particularly when we have that ugly
assignment.
If the intent is just to silence 'sparse', then replace with '!= NULL'.

> > makes the intent clear.
> 
> It would be a lot cleaner just to pull the entire assignment out of the
> for() statement. IOW:
> 
> 	for (shpp = &file->f_shares; *shpp != NULL; shpp = &(*shpp)->s_next) {
> 		struct nlm_share *share = *shpp;

...however doing something like the above would be altogether
preferable, since that cleans up the assignment which is the source of
the ugliness.

Cheers
  Trond


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2007-11-14 17:51 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-11-14  2:05 [PATCH] - [7/15] - remove defconfig ptr comparisons to 0 - fs/lockd Joe Perches
2007-11-14  2:40 ` Neil Brown
2007-11-14  4:45   ` Trond Myklebust
2007-11-14 17:50     ` Trond Myklebust

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