From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: [PATCH] pcm: Don't store the state for SND_PCM_STATE_SUSPENDED Date: Wed, 11 May 2016 09:13:09 +0200 Message-ID: References: <1462866346-11878-1-git-send-email-shengjiu.wang@freescale.com> Mime-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by alsa0.perex.cz (Postfix) with ESMTP id 9EF7626062E for ; Wed, 11 May 2016 09:13:10 +0200 (CEST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Shengjiu Wang Cc: "alsa-devel@alsa-project.org" List-Id: alsa-devel@alsa-project.org On Wed, 11 May 2016 08:24:55 +0200, Shengjiu Wang wrote: > > Hi > > > On Wed, 11 May 2016 04:28:41 +0200, > > Shengjiu Wang wrote: > > > > > > Hi > > > > > > > -----Original Message----- > > > > From: Takashi Iwai [mailto:tiwai@suse.de] > > > > Sent: Tuesday, May 10, 2016 4:22 PM > > > > To: Shengjiu Wang > > > > Cc: perex@perex.cz; alsa-devel@alsa-project.org > > > > Subject: Re: [PATCH] pcm: Don't store the state for > > > > SND_PCM_STATE_SUSPENDED > > > > > > > > On Tue, 10 May 2016 09:45:46 +0200, > > > > Shengjiu Wang wrote: > > > > > > > > > > The resume function don't update the dmix->state, if store > > SUSPENDED > > > > > state in snd_pcm_dmix_state, the write function after resume will > > > > > return error -ESTRPIPE, because the snd_pcm_write_areas() will > > check > > > > > the state of the pcm device. > > > > > This patch remove the store SND_PCM_STATE_SUSPENDED state > > operation > > > > > for dmix,dshare,dsnoop. > > > > > > > > > > Signed-off-by: Shengjiu Wang > > > > > > > > What's the exact problem you're seeing on surface? Could > > illustrate > > > > how the bug is triggered and how to reproduce easily? It'll make > > > > easier to understand what you're trying to fix. > > > > > > > > > > > > thanks, > > > > > > > > Takashi > > > > > > The aplay endlessly print " Suspended. Trying resume. Done." if > > suspend > > > and resume in the middle of playback. Which is caused by this patch. > > > > > > commit 8985742d91dbdd74b2f605374207473393454fff > > > Author: Takashi Iwai > > > Date: Fri Oct 30 17:13:50 2015 +0100 > > > > > > pcm: dmix: Handle slave PCM xrun and unexpected states properly > > > > > > This patch store the SUSPENDED state to dmix->state, but after resume > > > the dmix->state still is SUSPENDED, next write function will check > > the > > > state, if state is SUSPENDED, it will return -ESTRPIPE, then the > > aplay > > > will print another " Suspended. Trying resume. Done." Then repeat > > this > > > behavior again and again. > > > > Thanks, this is exactly what I wanted to see in the changelog! > > It's rather a regression, and it should be clearly mentioned. > > > > Now about your fix: the problem is not about setting the correct > > state at suspending. It is suspended, so setting the right state > > there is the correct behavior. However, the counterpart, the resume, > > is the culprit of this bug. It misses the restore of the shadow > > state. > > > > Does the patch below work instead? > > > Yes, it is workable. Great, now I pushed the fix to git tree. Thanks for your quick test! Takashi