| Message ID | 1412687631-28424-1-git-send-email-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 7 Oct 2014 14:13:51 +0100 Chris Wilson <chris@chris-wilson.co.uk> wrote: > The implmentation is simple in the extreme: we only want to wait for > events if the device was opened in blocking mode, otherwise we grab > what is available and report an error if there was none. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: dri-devel@lists.freedesktop.org > --- > drivers/gpu/drm/drm_fops.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c > index ed7bc68f7e87..91e1105f2800 100644 > --- a/drivers/gpu/drm/drm_fops.c > +++ b/drivers/gpu/drm/drm_fops.c > @@ -515,10 +515,12 @@ ssize_t drm_read(struct file *filp, char __user > *buffer, size_t total; > ssize_t ret; > > - ret = wait_event_interruptible(file_priv->event_wait, > - !list_empty(&file_priv->event_list)); > - if (ret < 0) > - return ret; > + if ((filp->f_flags & O_NONBLOCK) == 0) { > + ret = wait_event_interruptible(file_priv->event_wait, > + !list_empty(&file_priv->event_list)); > + if (ret < 0) > + return ret; > + } > > total = 0; > while (drm_dequeue_event(file_priv, total, count, &e)) { > @@ -532,7 +534,7 @@ ssize_t drm_read(struct file *filp, char __user > *buffer, e->destroy(e); > } > > - return total; > + return total ?: -EAGAIN; > } > EXPORT_SYMBOL(drm_read); I'd prefer "total" to be spelled out after the ? (is this just a GNU thing or does recent C implicitly use the first operand too?), but that's no biggie. Looks fine. Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
On Tue, Oct 7, 2014 at 3:13 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote: > The implmentation is simple in the extreme: we only want to wait for > events if the device was opened in blocking mode, otherwise we grab what > is available and report an error if there was none. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: dri-devel@lists.freedesktop.org Testcase for nonblocking behaviour in kms_flip? -Daniel
On Wed, Oct 08, 2014 at 11:16:38AM +0200, Daniel Vetter wrote: > On Tue, Oct 7, 2014 at 3:13 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote: > > The implmentation is simple in the extreme: we only want to wait for > > events if the device was opened in blocking mode, otherwise we grab what > > is available and report an error if there was none. > > > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > > Cc: dri-devel@lists.freedesktop.org > > Testcase for nonblocking behaviour in kms_flip? To the further dismay of anyone running kms_flip today, Testcase: igt/kms_flip/nonblocing_read -Chris
On Wed, Oct 08, 2014 at 10:45:48AM +0100, Chris Wilson wrote: > On Wed, Oct 08, 2014 at 11:16:38AM +0200, Daniel Vetter wrote: > > On Tue, Oct 7, 2014 at 3:13 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote: > > > The implmentation is simple in the extreme: we only want to wait for > > > events if the device was opened in blocking mode, otherwise we grab what > > > is available and report an error if there was none. > > > > > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > > > Cc: dri-devel@lists.freedesktop.org > > > > Testcase for nonblocking behaviour in kms_flip? > > To the further dismay of anyone running kms_flip today, > Testcase: igt/kms_flip/nonblocing_read Not if they upgrade to -nightly ;-) Thanks for the patch, merged to topic/core-stuff. -Daniel
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index ed7bc68f7e87..91e1105f2800 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -515,10 +515,12 @@ ssize_t drm_read(struct file *filp, char __user *buffer, size_t total; ssize_t ret; - ret = wait_event_interruptible(file_priv->event_wait, - !list_empty(&file_priv->event_list)); - if (ret < 0) - return ret; + if ((filp->f_flags & O_NONBLOCK) == 0) { + ret = wait_event_interruptible(file_priv->event_wait, + !list_empty(&file_priv->event_list)); + if (ret < 0) + return ret; + } total = 0; while (drm_dequeue_event(file_priv, total, count, &e)) { @@ -532,7 +534,7 @@ ssize_t drm_read(struct file *filp, char __user *buffer, e->destroy(e); } - return total; + return total ?: -EAGAIN; } EXPORT_SYMBOL(drm_read);
The implmentation is simple in the extreme: we only want to wait for events if the device was opened in blocking mode, otherwise we grab what is available and report an error if there was none. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: dri-devel@lists.freedesktop.org --- drivers/gpu/drm/drm_fops.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)