On 21.03.2016 19:18, Tanu Kaskinen wrote: > On Mon, 2016-03-21 at 16:06 +0100, Georg Chini wrote: >> On 21.03.2016 15:56, Tanu Kaskinen wrote: >>> On Mon, 2016-03-21 at 15:41 +0100, Georg Chini wrote: >>>> On 21.03.2016 15:11, Tanu Kaskinen wrote: >>>>> On Mon, 2016-03-21 at 15:53 +0200, Tanu Kaskinen wrote: >>>>>> That aside, it seems to me that we shouldn't care about the current >>>>>> cork state anyway. If the stream is corked when we send the cork >>>>>> request, the application has two reasons to have the stream corked: the >>>>>> first reason is whatever reason made the application cork the stream in >>>>>> the first place, and the second reason is our cork request. When we >>>>>> send the uncork request, only one of those reasons goes away. It's up >>>>>> to the application to keep track of its corking reasons, and keep the >>>>>> stream corked as long as there is any reason to do so. >>>>> The cork state checking was added here: >>>>> https://cgit.freedesktop.org/pulseaudio/pulseaudio/commit/?id=dda564f50b55340ff4bfbaa8d6d6fc6427f764f4 >>>>> >>>>> Colin mentions paused Rhythmbox as an example use case where it would >>>>> make sense to avoid sending the cork/uncork requests. In my opinion >>>>> Rhythmbox shouldn't blindly unpause when it receives an uncork request >>>>> from PulseAudio, but if it does, then it might not be a good idea to >>>>> change the logic. This should be tested, but Rhythmbox is somehow >>>>> totally broken on this machine (won't play anything), so I can't do >>>>> that. >>>> >>>> I don't touch the cork/uncork/mute/unmute logic for existing streams >>>> with that patch, only new streams are affected in so far that they are >>>> muted. >>> Yes, I know. Your patch ignores the cork state for new streams, which >>> is good, but I tried to suggest that maybe it would be even if we >>> ignored the cork state also for existing streams. >> OK, got you. But that would mean, that the application has to keep track >> of multiple cork requests. I am thinking about some stream that is corked >> manually. If we send an uncork request to that stream, there are three >> possible results: >> >> 1) Nothing happens, because the client ignores cork/uncork requests from >> the server >> 2) The client removes one "corking reason" but still keeps the stream corked >> 3) The stream is uncorked (which is unwanted because it was corked manually) >> >> There is probably no application out there that keeps track of the cork >> requests, and to avoid 3) I think we should keep the current logic. > You're right. I was expecting there to be more problems, because the > current logic prevents application from having information that it > might in theory need to manage the cork state correctly, but when > manual corking is the only other "competing" source, I couldn't think > of any use case where the current logic would fail. > > If the application does any kind of automatic corking, then incorrect > uncorking may happen. I don't know any real-world use cases, but I can > imagine some application that produces sound while some condition holds > and other times stays silent (corked). For example, maybe I want to > play music every morning from 9 to 10, and I make a program that is > always running, but keeps the stream corked most of the time. Let's say > that at 8:50 a phone call comes in, and it lasts more than 10 minutes. > Since my application didn't get a cork request, because it was corked > when the phone call started, it doesn't know that it should keep the > stream corked, so music starts to play at 9 o'clock. > > I'll apply the patch as is. > > -- > Tanu Thanks for your review!
