Re: [PATCH v2 06/13] staging/android: remove name arg from sync_file_create()

From: Gustavo Padovan
Date: Fri Apr 29 2016 - 10:16:44 EST


Hi Hillf,

(please keep the whole cc on the reply, so others can see it too)

2016-04-29 Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx>:

> >
> > From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>
> >
> > Simplifies the API to only receive the fence it needs to add to the
> > sync and create a name for the sync_file based on the fence context and
> > seqno.
> >
> > Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>
> > Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
> > ---
> > drivers/staging/android/sync.c | 16 +++++++++-------
> > drivers/staging/android/sync.h | 2 +-
> > drivers/staging/android/sync_debug.c | 3 +--
> > 3 files changed, 11 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c
> > index 7e0fa20..5470ae9 100644
> > --- a/drivers/staging/android/sync.c
> > +++ b/drivers/staging/android/sync.c
> > @@ -136,7 +136,7 @@ struct fence *sync_pt_create(struct sync_timeline *obj, int size)
> > }
> > EXPORT_SYMBOL(sync_pt_create);
> >
> > -static struct sync_file *sync_file_alloc(int size, const char *name)
> > +static struct sync_file *sync_file_alloc(int size)
> > {
> > struct sync_file *sync_file;
> >
> > @@ -150,7 +150,6 @@ static struct sync_file *sync_file_alloc(int size, const char *name)
> > goto err;
> >
> > kref_init(&sync_file->kref);
> > - strlcpy(sync_file->name, name, sizeof(sync_file->name));
> >
> > init_waitqueue_head(&sync_file->wq);
> >
> > @@ -175,23 +174,25 @@ static void fence_check_cb_func(struct fence *f, struct fence_cb *cb)
> >
> > /**
> > * sync_fence_create() - creates a sync fence
> > - * @name: name of fence to create
> > * @fence: fence to add to the sync_fence
> > *
> > * Creates a sync_file containg @fence. Once this is called, the sync_file
> > * takes ownership of @fence.
> > */
> > -struct sync_file *sync_file_create(const char *name, struct fence *fence)
> > +struct sync_file *sync_file_create(struct fence *fence)
> > {
> > struct sync_file *sync_file;
> >
> > - sync_file = sync_file_alloc(offsetof(struct sync_file, cbs[1]),
> > - name);
> > + sync_file = sync_file_alloc(offsetof(struct sync_file, cbs[1]));
> > if (!sync_file)
> > return NULL;
> >
> > sync_file->num_fences = 1;
> > atomic_set(&sync_file->status, 1);
> > + snprintf(sync_file->name, sizeof(sync_file->name), "%s-%s%d-%d",
> > + fence->ops->get_driver_name(fence),
> > + fence->ops->get_timeline_name(fence), fence->context,
> > + fence->seqno);
> >
> > sync_file->cbs[0].fence = fence;
> > sync_file->cbs[0].sync_file = sync_file;
> > @@ -260,7 +261,7 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
> > int i, i_a, i_b;
> > unsigned long size = offsetof(struct sync_file, cbs[num_fences]);
> >
> > - sync_file = sync_file_alloc(size, name);
> > + sync_file = sync_file_alloc(size);
> > if (!sync_file)
> > return NULL;
> >
> > @@ -306,6 +307,7 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
> > atomic_sub(num_fences - i, &sync_file->status);
> > sync_file->num_fences = i;
> >
> > + strlcpy(sync_file->name, name, sizeof(sync_file->name));
> > sync_file_debug_add(sync_file);
> > return sync_file;
> > }
> > diff --git a/drivers/staging/android/sync.h b/drivers/staging/android/sync.h
> > index 1f164df..7dee444 100644
> > --- a/drivers/staging/android/sync.h
> > +++ b/drivers/staging/android/sync.h
> > @@ -167,7 +167,7 @@ void sync_timeline_signal(struct sync_timeline *obj);
> > */
> > struct fence *sync_pt_create(struct sync_timeline *parent, int size);
> >
> > -struct sync_file *sync_file_create(const char *name, struct fence *fence);
> > +struct sync_file *sync_file_create(struct fence *fence);
> >
> > #ifdef CONFIG_DEBUG_FS
> >
> > diff --git a/drivers/staging/android/sync_debug.c b/drivers/staging/android/sync_debug.c
> > index e4b0e41..2cab40d 100644
> > --- a/drivers/staging/android/sync_debug.c
> > +++ b/drivers/staging/android/sync_debug.c
> > @@ -262,8 +262,7 @@ static long sw_sync_ioctl_create_fence(struct sw_sync_timeline *obj,
> > goto err;
> > }
> >
> > - data.name[sizeof(data.name) - 1] = '\0';
> > - sync_file = sync_file_create(data.name, fence);
> > + sync_file = sync_file_create(fence);
>
>
> The name injected from user spce is ignored, why?
> Is it a semantic change?

It is. sw_sync is only a testing API that we are not de-staging now.

I think we we will just remove the name arg from the ioctl there.
SW_SYNC ioctl is only for debugging test, we don't want to publicly
export its ABI in the kernel uapi headers.

> Mentioned in commit message?

Sure, I can update the commit message.

Gustavo