Re: [PATCH 8/9] hw/9pfs/9p-synth: Replaced qemu_mutex_lock with QEMU_LOCK_GUARD

[Greg Kurz]

On Thu, 11 Mar 2021 11:49:06 +0100
Christian Schoenebeck <qemu_oss@crudebyte.com> wrote:

> On Donnerstag, 11. März 2021 04:15:37 CET Mahmoud Mandour wrote:
> > Replaced a call to qemu_mutex_lock and its respective call to
> > qemu_mutex_unlock and used QEMU_LOCK_GUARD macro in their place.
> > This simplifies the code by removing the call required to unlock
> > and also eliminates goto paths.
> > 
> > Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
> > ---
> >  hw/9pfs/9p-synth.c | 12 ++++--------
> >  1 file changed, 4 insertions(+), 8 deletions(-)
> > 
> > diff --git a/hw/9pfs/9p-synth.c b/hw/9pfs/9p-synth.c
> > index 7eb210ffa8..473ef914b0 100644
> > --- a/hw/9pfs/9p-synth.c
> > +++ b/hw/9pfs/9p-synth.c
> > @@ -79,11 +79,11 @@ int qemu_v9fs_synth_mkdir(V9fsSynthNode *parent, int
> > mode, if (!parent) {
> >          parent = &synth_root;
> >      }
> > -    qemu_mutex_lock(&synth_mutex);
> > +    QEMU_LOCK_GUARD(&synth_mutex);
> >      QLIST_FOREACH(tmp, &parent->child, sibling) {
> >          if (!strcmp(tmp->name, name)) {
> >              ret = EEXIST;
> > -            goto err_out;
> > +            return ret;
> >          }
> >      }
> >      /* Add the name */
> > @@ -94,8 +94,6 @@ int qemu_v9fs_synth_mkdir(V9fsSynthNode *parent, int mode,
> > node->attr, node->attr->inode);
> >      *result = node;
> >      ret = 0;
> > -err_out:
> > -    qemu_mutex_unlock(&synth_mutex);
> >      return ret;
> >  }
> > 
> > @@ -116,11 +114,11 @@ int qemu_v9fs_synth_add_file(V9fsSynthNode *parent,
> > int mode, parent = &synth_root;
> >      }
> > 
> > -    qemu_mutex_lock(&synth_mutex);
> > +    QEMU_LOCK_GUARD(&synth_mutex);
> >      QLIST_FOREACH(tmp, &parent->child, sibling) {
> >          if (!strcmp(tmp->name, name)) {
> >              ret = EEXIST;
> > -            goto err_out;
> > +            return ret;
> >          }
> >      }
> >      /* Add file type and remove write bits */
> > @@ -136,8 +134,6 @@ int qemu_v9fs_synth_add_file(V9fsSynthNode *parent, int
> > mode, pstrcpy(node->name, sizeof(node->name), name);
> >      QLIST_INSERT_HEAD_RCU(&parent->child, node, sibling);
> >      ret = 0;
> > -err_out:
> > -    qemu_mutex_unlock(&synth_mutex);
> >      return ret;
> >  }
> 
> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
> 
> Greg, I suggest I'll push this onto my queue as you seem to be busy.
> 

This cleanup spans over multiple subsystems but I think it makes more
sense to keep all these patches together. Let's wait for everyone to
ack/review and then we'll decide how to merge the patches.

> Best regards,
> Christian Schoenebeck
> 
>