From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mga09.intel.com ([134.134.136.24]:27430 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754416Ab3JBNos (ORCPT ); Wed, 2 Oct 2013 09:44:48 -0400 From: Sakari Ailus To: linux-media@vger.kernel.org Cc: hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com, teemux.tuominen@intel.com Subject: [RFC v2 2/4] v4l: vb2: Only poll for events if the user is interested in them Date: Wed, 2 Oct 2013 16:45:14 +0300 Message-Id: <1380721516-488-3-git-send-email-sakari.ailus@linux.intel.com> In-Reply-To: <1380721516-488-1-git-send-email-sakari.ailus@linux.intel.com> References: <1380721516-488-1-git-send-email-sakari.ailus@linux.intel.com> Sender: linux-media-owner@vger.kernel.org List-ID: Also poll_wait() before checking the events since otherwise it's possible to go to sleep and not getting woken up if the event arrives between the two operations. Signed-off-by: Sakari Ailus --- drivers/media/v4l2-core/videobuf2-core.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index 594c75e..79acf5e 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -2003,13 +2003,14 @@ unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) unsigned int res = 0; unsigned long flags; - if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { + if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags) && + req_events & POLLPRI) { struct v4l2_fh *fh = file->private_data; + poll_wait(file, &fh->wait, wait); + if (v4l2_event_pending(fh)) res = POLLPRI; - else if (req_events & POLLPRI) - poll_wait(file, &fh->wait, wait); } if (!V4L2_TYPE_IS_OUTPUT(q->type) && !(req_events & (POLLIN | POLLRDNORM))) -- 1.8.3.2