| Message ID | 7acd1c78-ea86-7776-d98d-c846186e4b88@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 04, 2017 at 12:34:00PM +0100, Maarten Lankhorst wrote: > Op 04-01-17 om 12:28 schreef Daniel Vetter: > > On Wed, Jan 04, 2017 at 11:22:54AM +0000, Chris Wilson wrote: > >> On Wed, Jan 04, 2017 at 12:15:55PM +0100, Maarten Lankhorst wrote: > >>> Op 15-12-16 om 16:19 schreef Daniel Vetter: > >>>> On Thu, Dec 15, 2016 at 03:29:42PM +0100, Maarten Lankhorst wrote: > >>>>> drm_atomic_state_put is called unconditionally, so TEST_ONLY is no > >>>>> different from commit. > >>>>> > >>>>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> > >>>> I think it'd be good to update the kerneldoc for the atomic_commit > >>>> callback to mention that drivers should grab their own references using > >>>> drm_atomic_state_get() when they need it. > >>>> > >>>> Applied this one meanwhile, thanks. > >>> --->8--- > >>> Commit 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state") > >>> adds reference counting to atomic state, but didn't update the comments > >>> in drm_atomic_(nonblocking_)commit. Clarify lifetime a bit more. > >>> > >>> Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state") > >>> Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+ > >>> Cc: Chris Wilson <chris@chris-wilson.co.uk> > >>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> > >>> --- > >>> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > >>> index 681d5f97639d..6492546476b4 100644 > >>> --- a/drivers/gpu/drm/drm_atomic.c > >>> +++ b/drivers/gpu/drm/drm_atomic.c > >>> @@ -1599,10 +1599,9 @@ EXPORT_SYMBOL(drm_atomic_check_only); > >>> * more locks but encountered a deadlock. The caller must then do the usual w/w > >>> * backoff dance and restart. All other errors are fatal. > >>> * > >>> - * Also note that on successful execution ownership of @state is transferred > >>> - * from the caller of this function to the function itself. The caller must not > >>> - * free or in any other way access @state. If the function fails then the caller > >>> - * must clean up @state itself. > >>> + * In earlier versions of the atomic api, the caller was handing its reference > >>> + * of @state over to this function on success. This is no longer the case, and > >>> + * callers should always call drm_atomic_state_put(). > >>> * > >>> * Returns: > >>> * 0 on success, negative error code on failure. > >>> @@ -1630,10 +1629,9 @@ EXPORT_SYMBOL(drm_atomic_commit); > >>> * more locks but encountered a deadlock. The caller must then do the usual w/w > >>> * backoff dance and restart. All other errors are fatal. > >>> * > >>> - * Also note that on successful execution ownership of @state is transferred > >>> - * from the caller of this function to the function itself. The caller must not > >>> - * free or in any other way access @state. If the function fails then the caller > >>> - * must clean up @state itself. > >>> + * In earlier versions of the atomic api, the caller was handing its reference > >>> + * of @state over to this function on success. This is no longer the case, and > >>> + * callers should always call drm_atomic_state_put(). > >> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> > >> > >> But do we really want the confusion of mentioning what the api doesn't do > >> any more? > > Agreed, kerneldoc should state what is (and why), maybe with a FIXME if it > > only makes sense with some hystorical context and what should be done > > instead. git blame is for figuring out what was. > > > > Maarten, can you pls respin? > > -Daniel > > ----8<--- > Commit 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state") > adds reference counting to atomic state, but didn't update the comments > in drm_atomic_(nonblocking_)commit. Clarify lifetime a bit more. > > Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state") > Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+ > Cc: Chris Wilson <chris@chris-wilson.co.uk> > Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> > Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Applied to drm-misc, thanks. -Daniel > --- > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 681d5f97639d..672f1de84d6c 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -1599,10 +1599,8 @@ EXPORT_SYMBOL(drm_atomic_check_only); > * more locks but encountered a deadlock. The caller must then do the usual w/w > * backoff dance and restart. All other errors are fatal. > * > - * Also note that on successful execution ownership of @state is transferred > - * from the caller of this function to the function itself. The caller must not > - * free or in any other way access @state. If the function fails then the caller > - * must clean up @state itself. > + * This function will take its own reference on @state. > + * Callers should always release their reference with drm_atomic_state_put(). > * > * Returns: > * 0 on success, negative error code on failure. > @@ -1630,10 +1628,8 @@ EXPORT_SYMBOL(drm_atomic_commit); > * more locks but encountered a deadlock. The caller must then do the usual w/w > * backoff dance and restart. All other errors are fatal. > * > - * Also note that on successful execution ownership of @state is transferred > - * from the caller of this function to the function itself. The caller must not > - * free or in any other way access @state. If the function fails then the caller > - * must clean up @state itself. > + * This function will take its own reference on @state. > + * Callers should always release their reference with drm_atomic_state_put(). > * > * Returns: > * 0 on success, negative error code on failure. >
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 681d5f97639d..672f1de84d6c 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -1599,10 +1599,8 @@ EXPORT_SYMBOL(drm_atomic_check_only); * more locks but encountered a deadlock. The caller must then do the usual w/w * backoff dance and restart. All other errors are fatal. * - * Also note that on successful execution ownership of @state is transferred - * from the caller of this function to the function itself. The caller must not - * free or in any other way access @state. If the function fails then the caller - * must clean up @state itself. + * This function will take its own reference on @state. + * Callers should always release their reference with drm_atomic_state_put(). * * Returns: * 0 on success, negative error code on failure. @@ -1630,10 +1628,8 @@ EXPORT_SYMBOL(drm_atomic_commit); * more locks but encountered a deadlock. The caller must then do the usual w/w * backoff dance and restart. All other errors are fatal. * - * Also note that on successful execution ownership of @state is transferred - * from the caller of this function to the function itself. The caller must not - * free or in any other way access @state. If the function fails then the caller - * must clean up @state itself. + * This function will take its own reference on @state. + * Callers should always release their reference with drm_atomic_state_put(). * * Returns: * 0 on success, negative error code on failure.