From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: Atomic operators in alsa driver Date: Mon, 16 Aug 2004 12:34:30 +0200 Sender: alsa-devel-admin@lists.sourceforge.net Message-ID: References: <20040810215154.8910.h006.c012.wm@mail.icqmail.com.criticalpath.net> Mime-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Jaroslav Kysela Cc: Eliot Blennerhassett , alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org At Wed, 11 Aug 2004 15:19:20 +0200 (CEST), Jaroslav wrote: > > On Tue, 10 Aug 2004, Eliot Blennerhassett wrote: > > > A question to clarify which 'operators' are atomic i.e. inside spinlock. > > > > As far as I can make out from Takashi's Writing an Alsa driver, Chapter 5, > > section "Operators" (am I correct?) > > > > Atomic: > > trigger callback > > pointer callback > > > > Non-atomic: > > open callback > > close callback > > ioctl callback > > hw_params callback > > hw_free callback > > prepare callback > > copy and silence callbacks > > ack callback > > page callback > > It's correct. In practice, ack callback is usually treated as atomic to get finer processing of data transfer. For example, ack is called in the pointer callback in pcm-indirect.h. But basically it can be non-atomic, too. Takashi ------------------------------------------------------- SF.Net email is sponsored by Shop4tech.com-Lowest price on Blank Media 100pk Sonic DVD-R 4x for only $29 -100pk Sonic DVD+R for only $33 Save 50% off Retail on Ink & Toner - Free Shipping and Free Gift. http://www.shop4tech.com/z/Inkjet_Cartridges/9_108_r285