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=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 B63B7C4338F for ; Tue, 17 Aug 2021 18:28:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8572160FA0 for ; Tue, 17 Aug 2021 18:28:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232280AbhHQS25 (ORCPT ); Tue, 17 Aug 2021 14:28:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55080 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232378AbhHQS24 (ORCPT ); Tue, 17 Aug 2021 14:28:56 -0400 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74BB9C061764 for ; Tue, 17 Aug 2021 11:28:23 -0700 (PDT) Received: by mail-pj1-x102c.google.com with SMTP id bo18so570485pjb.0 for ; Tue, 17 Aug 2021 11:28:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=OHvEnRLjEptuXUny5W4npQ32FfB7O0orXAKt62vh8N8=; b=kb1GGIfC2AwwPHWIg2EYbOMqnZrAq0UN9UsBtZXo9d58E+f0KHUr4+G4eicSMPELGG PZomt7Ks/3ZcNYm1xtNv6/J+8LeC0HijyDPkrQDDkYY74B7XC5k2s25THt1D0T8Rum6z fw7JqCECPjZedbWG7TC47k3t0sPvyU1kw87sbzAonHyHXyNfdlyjrRmcn6DM7H+LmPBx 9mcl5TorbTq2GN9ajA+4VdiZY+RAzskCyw8b9gCxqY12785/b8WHAglf0NDsZntVNcFq BvHTEfmr1kco0dbuIv6r/BSQNnuIGMEaHh79LaOO7I9RqVYo9T9UdM+H8JqDU3CMoHUV tuew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=OHvEnRLjEptuXUny5W4npQ32FfB7O0orXAKt62vh8N8=; b=QJt0UIy1c/z/5XuUs5yUHv1FbaZyifk5Pm9UAdHu3PbqGe1ZErhoejHKZy/U+D4TFR sEKlwfVgYiZ/Y3yh9eJ+ml6cPiwTLkQqMXBkZKTBwrS5zbB1goj0diKO4slmCl/Bt8y9 XKYoypv4CoGtzYcZAL0r64YPJu6XHeJSBYutR5ybd5fT7z70d2kHHbmtCAON0NXz4iGB 4IzDtrCdxVzITED2YRGXfSANiUhFkVWZlqKlnHN8/KjKUNPkoN+sJrg83X7EddUpX057 HGOp1sxrwDPOlFqTZy9FsdJldjwbrlcY8OkhcdkknUk7jOqKLQ2G1AeFtrgjetD1GyNf 8UXg== X-Gm-Message-State: AOAM53304ypbjN/gDe6tuFOM8kyIge+ytweWe8iSGCydicPDrhgKfOwW sydh07hkhUNgAdt3hh/Wow8= X-Google-Smtp-Source: ABdhPJwmzUMaCwXYicrFH4VwP7h05OQCtQNqSXX9DS1SQlsWFWV0f4BXtsmh4+YD36t+84rr3Qp/cA== X-Received: by 2002:a62:ee16:0:b029:2fe:ffcf:775a with SMTP id e22-20020a62ee160000b02902feffcf775amr4775601pfi.59.1629224902831; Tue, 17 Aug 2021 11:28:22 -0700 (PDT) Received: from localhost (2603-800c-1a02-1bae-e24f-43ff-fee6-449f.res6.spectrum.com. [2603:800c:1a02:1bae:e24f:43ff:fee6:449f]) by smtp.gmail.com with ESMTPSA id p17sm3383296pfh.33.2021.08.17.11.28.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Aug 2021 11:28:22 -0700 (PDT) Sender: Tejun Heo Date: Tue, 17 Aug 2021 08:28:21 -1000 From: Tejun Heo To: Sean Anderson Cc: Arend van Spriel , linux-wireless@vger.kernel.org, Kalle Valo , Chi-hsien Lin , Franky Lin , SHA-cyfmac-dev-list@infineon.com, Hante Meuleman , Wright Feng , Arend Van Spriel , brcm80211-dev-list.pdl@broadcom.com Subject: Re: [PATCH] brcmfmac: Set SDIO workqueue as WQ_HIGHPRI Message-ID: References: <20210802170904.3116223-1-sean.anderson@seco.com> <17b551dc6e0.279b.9696ff82abe5fb6502268bdc3b0467d4@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Hello, On Tue, Aug 17, 2021 at 02:21:55PM -0400, Sean Anderson wrote: > > While I understand the obvious gain it seems like a wrong move to me. What if all workqueues in the kernel would start using this flag? I bet the gain above would be negated and all are equal in the eyes of .. the kernel > > Is there an official policy on what counts as high-priority? Using some > very-scientific methodology [1], it seems like most high-priority > workqueues are in drivers/net and fs. Making these queues high-priority > seems to be commonplace. For example, in fe101716c7c9 ("rtw88: replace > tx tasklet with work queue"), Po-Hao Huang remarks: I think this is actually a good candidate for HIGHPRI. As you noted, stuff which interacts with hardware in latency sensitive manner with impact on observable performance is one of the common use cases. The alternatives would be doing it from hard/softirqs which are higher priorities anyway. Thanks. -- tejun