From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9F9EC3B1BB for ; Fri, 13 Dec 2019 20:41:53 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 26F242470F for ; Fri, 13 Dec 2019 20:41:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="fxpL+5gt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 26F242470F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 9EAF01788; Fri, 13 Dec 2019 14:34:23 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 9EAF01788 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1576244113; bh=k58UueqGF7daLdlU/C9jqufGnz+ONjEumWRY/pPwKAM=; h=Date:From:To:In-Reply-To:References:Cc:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=fxpL+5gtXbvhIguWfKHK/Z6jyqzUt86lurAp8sknlVEEMJrPw58/HPSYsyUbfUk24 R63VZaBT/smG58RGOLExrV834Fh1PTYKSIASH3wy6sz6VRCvU6Of2dl9R7AOGA2Hhp KaZFxNdwdTO3NnvY2RrwdFk2mojOE4FXT4ossggo= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 184F1F8019B; Fri, 13 Dec 2019 14:34:23 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 3F4E5F801F4; Fri, 13 Dec 2019 14:34:22 +0100 (CET) Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 167BEF8014F for ; Fri, 13 Dec 2019 14:34:15 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 167BEF8014F X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 78D9FAE5E; Fri, 13 Dec 2019 13:34:13 +0000 (UTC) Date: Fri, 13 Dec 2019 14:34:13 +0100 Message-ID: From: Takashi Iwai To: Kai Vehmanen In-Reply-To: References: <20191210145727.22054-1-tiwai@suse.de> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Cc: alsa-devel@alsa-project.org Subject: Re: [alsa-devel] [PATCH] ALSA: hda: Use standard waitqueue for RIRB wakeup X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On Fri, 13 Dec 2019 14:05:31 +0100, Kai Vehmanen wrote: > > Hey, > > On Tue, 10 Dec 2019, Takashi Iwai wrote: > > > This patch attempts to improve the situation by introducing the > > standard waitqueue in the RIRB waiter side instead of polling. The > > this patch was part of the testing as well, so looks good. One minor > nit only: > > > @@ -216,6 +216,9 @@ void snd_hdac_bus_update_rirb(struct hdac_bus *bus) > > else if (bus->rirb.cmds[addr]) { > > bus->rirb.res[addr] = res; > > bus->rirb.cmds[addr]--; > > + if (!bus->rirb.cmds[addr] && > > + waitqueue_active(&bus->rirb_wq)) > > + wake_up(&bus->rirb_wq); > > Checkpath would like to have a comment here: > > WARNING: waitqueue_active without comment > #77: FILE: sound/hda/hdac_controller.c:220: > + waitqueue_active(&bus->rirb_wq)) Yeah, that was known to me, too. Actually it's misleading; what actually matters is the memory barrier or other synchronization there, and this should work as is because of the current code path. (Besides, majority of existing waitqueue_active() have no comments at all :) And, now I found wa_has_sleeper() as a better replacement of waitqueue_active() that explicitly cares about synchronization. So I'll change with this in a later patch (after unification to hda-core). thanks, Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel