From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcel Holtmann Subject: Re: External PCM plugin SDK Date: Thu, 10 Feb 2005 20:04:30 +0100 Message-ID: <1108062270.15974.117.camel@pegasus> References: <1107958458.13863.43.camel@pegasus> <1107959869.13863.62.camel@pegasus> <1107970036.13863.77.camel@pegasus> <1107971323.13863.90.camel@pegasus> <1108038565.15974.20.camel@pegasus> <1108057507.15974.97.camel@pegasus> <1108058761.15974.107.camel@pegasus> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit In-Reply-To: Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Takashi Iwai Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org Hi Takashi, > > > > > > The delayed close in the plugin is of course good to have. > > > > > > My only concern is that the code would be complicated to handle > > > > > > races. > > > > > > > > > > actually I see a lifetime race inside the plugin if I try to handle it > > > > > by myself. When the close() callback is called, I must free all of my > > > > > allocated resources, because the shared object will be unloaded, right? > > > > > > > > Yes, the close callback should clean up everything since there is no > > > > distinction between close and unload, so far. > > > > > > if the ALSA core is not handling the XMMS behaviour for us, I really > > > need something to distinguish between close and unload. > > > > > > What do you think about doing it like with kernel modules? Means we add > > > an init and an exit entry point inside the plugin. The rest is done via > > > callbacks. With this we should be able to register a PCM and also the > > > mixer controls for it within the same plugin. > > > > That's a good idea. > > ... and doesn't work as it is, unfortunately :-< > > dlcose() is called after snd_pcm_close(). > We may need to build object caches in alsa-lib. > This will improve the perfomance eventually, too. questions is what will break if you change it. The only official plugin is the Jack plugin, right? So be bad and change this stuff and then fix the plugins. Maybe a delayed unload (idle timeout) and adding reference counting to a plugin will help here. Regards Marcel ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click