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 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D6C9BC433EF for ; Fri, 22 Jul 2022 18:33:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658514835; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=/ZvFAZwIjw4DxmEyLxdzEJUP0pojhfvOeQGPpkwwIVQ=; b=e/apb4m56dAH0YXEFyGABgJJEu9I/Chc4yvVGV7werFXATJi34YCjPoE08vH614Dj72OLx YQTV0/ZKmRZuctBxXk2uT64MSGIxo3ihFrNonl0rYfliN6OnOXu4+4s85K5oEpoP8hdKg/ 0U/Ntwg5hvZEp/ITnzMF0N2fQ0jtvdg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-599-vbn6cEdoOSecls3xKn59XQ-1; Fri, 22 Jul 2022 14:33:51 -0400 X-MC-Unique: vbn6cEdoOSecls3xKn59XQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6E2242812C3C; Fri, 22 Jul 2022 18:33:49 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (unknown [10.30.29.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1B5BD492C3B; Fri, 22 Jul 2022 18:33:49 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (localhost [IPv6:::1]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id F4093194704D; Fri, 22 Jul 2022 18:33:48 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id E40BD1947049 for ; Fri, 22 Jul 2022 18:33:47 +0000 (UTC) Received: by smtp.corp.redhat.com (Postfix) id B2E7418EBB; Fri, 22 Jul 2022 18:33:47 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast09.extmail.prod.ext.rdu2.redhat.com [10.11.55.25]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AF56418ECB for ; Fri, 22 Jul 2022 18:33:47 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 928022812C22 for ; Fri, 22 Jul 2022 18:33:47 +0000 (UTC) Received: from mail-qk1-f197.google.com (mail-qk1-f197.google.com [209.85.222.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-359-Fn-e8cLaPdajjpFpUZAAvA-1; Fri, 22 Jul 2022 14:33:46 -0400 X-MC-Unique: Fn-e8cLaPdajjpFpUZAAvA-1 Received: by mail-qk1-f197.google.com with SMTP id v13-20020a05620a0f0d00b006b5f0ec742eso4289066qkl.2 for ; Fri, 22 Jul 2022 11:33:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=cuAxCjPb5JwgxHvfPH5uVtncIHsSNNJ86IoETDkzjWI=; b=5WclXATQC2GKzjjoGQySQXvKjn54XuIS9snibfZ/YrdxT9+EQdLRH7xtUhjO+BSQ11 J40FSmzwoxbE8zDrse+eHNXoELsYpoF/ijQQu1qJ4TImt88Pjk9VYzf81VbbzDW0IPzF M6furljSuNnfQu4AipJ7dkNO/Z/1bo9qUIKp7s4GXtNELX0oi5jgLQJUhw6/GVLZcmNB ET2E/6SWBPUiH6Mr3R18iX1gjQnzXysJKkhAJiXRhlK8YnmqbbT8hSnlPrV3H7rsTwma av6fpA8QC/co2PJ5PF3x+3dn47kHiPRtplSHYOgNqc3h3s92jWMaEfJWkW+jWN84gl6n SIiw== X-Gm-Message-State: AJIora9W/2GO33FUbHwLWi/ynhN86XpWUfiDf0+wy19JY8NfINIo6Gl/ 92mwrycXgkS71xMWPkFJ1pFrJSq/qn+cfAlxPDNnP57/6y7vSpm87+PpFobyCrTbMAuy6ZqJFWL faBV9/NTSGj7pCA== X-Received: by 2002:a05:6214:d66:b0:473:7906:ac4f with SMTP id 6-20020a0562140d6600b004737906ac4fmr1312623qvs.126.1658514825961; Fri, 22 Jul 2022 11:33:45 -0700 (PDT) X-Google-Smtp-Source: AGRyM1uwdMklIfR1RPb6muiHD6u2FhgP1jhA5kPEp8IEKapJ297TmS1h5GutOZjOQ2Ki8tYs42IJtg== X-Received: by 2002:a05:6214:d66:b0:473:7906:ac4f with SMTP id 6-20020a0562140d6600b004737906ac4fmr1312606qvs.126.1658514825674; Fri, 22 Jul 2022 11:33:45 -0700 (PDT) Received: from localhost (pool-68-160-176-52.bstnma.fios.verizon.net. [68.160.176.52]) by smtp.gmail.com with ESMTPSA id v17-20020a05620a0f1100b006b55036fd3fsm3882891qkl.70.2022.07.22.11.33.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Jul 2022 11:33:45 -0700 (PDT) Date: Fri, 22 Jul 2022 14:33:44 -0400 From: Mike Snitzer To: Bart Van Assche Message-ID: References: <20220722093823.4158756-1-nhuck@google.com> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Subject: Re: [dm-devel] [PATCH 0/3] dm-verity: optionally use tasklets in dm-verity X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eric Biggers , Sebastian Andrzej Siewior , Mike Snitzer , linux-kernel@vger.kernel.org, Nathan Huckleberry , Christoph Hellwig , dm-devel@redhat.com, Sami Tolvanen , Thomas Gleixner , Alasdair Kergon Errors-To: dm-devel-bounces@redhat.com Sender: "dm-devel" X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Fri, Jul 22 2022 at 2:12P -0400, Bart Van Assche wrote: > On 7/22/22 09:41, Christoph Hellwig wrote: > > We've been tying to kill off task lets for about 15 years. I don't > > think adding new users will make you a whole lot of friends.. > > +1 for not using tasklets. At least in Android the real-time thread > scheduling latency is important. Tasklets are not visible to the scheduler > and hence cause latency spikes for real-time threads. These latency spikes > can be observed by users, e.g. if the real-time thread is involved in audio > playback. OK, then android wouldn't set the _optional_ "try_verify_in_tasklet" Mike -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E12C8C43334 for ; Fri, 22 Jul 2022 18:33:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236361AbiGVSdw (ORCPT ); Fri, 22 Jul 2022 14:33:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236366AbiGVSdu (ORCPT ); Fri, 22 Jul 2022 14:33:50 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 943DF9FE02 for ; Fri, 22 Jul 2022 11:33:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658514827; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=cuAxCjPb5JwgxHvfPH5uVtncIHsSNNJ86IoETDkzjWI=; b=VkQ3V3glT11ihfQbjIHCHlr0yn6Udp4bQi8C+Qw5E2pcRkaXv7z7Yj9e6mdD3UPdwCuKgg p8gra1UZTjo0GRvie1NmMwsAxw4FjP56JKvSZ3bJTvsiCgqrve/fPz1SCuMQ/usEzU9zSy xZHma3JFnbRuQoj278Mwc7r6hn44HzA= Received: from mail-qk1-f199.google.com (mail-qk1-f199.google.com [209.85.222.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-359-OSNAjzr8PCyOtlcVASd4UA-1; Fri, 22 Jul 2022 14:33:46 -0400 X-MC-Unique: OSNAjzr8PCyOtlcVASd4UA-1 Received: by mail-qk1-f199.google.com with SMTP id o13-20020a05620a2a0d00b006b46c5414b0so4345983qkp.23 for ; Fri, 22 Jul 2022 11:33:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=cuAxCjPb5JwgxHvfPH5uVtncIHsSNNJ86IoETDkzjWI=; b=GE6fnYnQVTX2Tyo/XxDrbuq/tIdFKEDY58uumXFsxAoYabaBEdCJyiJga5el3/Fl7f kIyDH/tf85uJjcKjU1aIC1KZvSwxUqozu1wmHGNrnLDxhoRwhqjdTVoFTPay2TkUBoUx gDc3Z1o48wPBqGP9JHET3hgdrrDMarFvOUL80/Pd3qIyIBw62vZPxV0cVfomTPAm2u2R LvByGFCJjNK+0v2BOSqZCn8cWglz9LHPOSysTyouYD6qdwfBZ2s8BYJeZU7d2qDDDDAi lv1S/6DW3tpnUwINFWKf66ctxI60rZ5MVPb9yF1bv1xzpcIXfNFCYuHoZglBA4uaQpy0 O6EA== X-Gm-Message-State: AJIora8AEx41mprVebUqb5UTkSvqismSR+zw9hkvn9wvBmaj6YtNkusd FtmkCqLGvJzsH7ml04msLqzrMidbNUSenFsBxIuuHNXkgyUNL2QTauZhTkD2tfUYq71IjoV30hK wUe4oE76lf8MAj9XOTTeyFNQ= X-Received: by 2002:a05:6214:d66:b0:473:7906:ac4f with SMTP id 6-20020a0562140d6600b004737906ac4fmr1312619qvs.126.1658514825963; Fri, 22 Jul 2022 11:33:45 -0700 (PDT) X-Google-Smtp-Source: AGRyM1uwdMklIfR1RPb6muiHD6u2FhgP1jhA5kPEp8IEKapJ297TmS1h5GutOZjOQ2Ki8tYs42IJtg== X-Received: by 2002:a05:6214:d66:b0:473:7906:ac4f with SMTP id 6-20020a0562140d6600b004737906ac4fmr1312606qvs.126.1658514825674; Fri, 22 Jul 2022 11:33:45 -0700 (PDT) Received: from localhost (pool-68-160-176-52.bstnma.fios.verizon.net. [68.160.176.52]) by smtp.gmail.com with ESMTPSA id v17-20020a05620a0f1100b006b55036fd3fsm3882891qkl.70.2022.07.22.11.33.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Jul 2022 11:33:45 -0700 (PDT) Date: Fri, 22 Jul 2022 14:33:44 -0400 From: Mike Snitzer To: Bart Van Assche Cc: Christoph Hellwig , Nathan Huckleberry , Sebastian Andrzej Siewior , Mike Snitzer , linux-kernel@vger.kernel.org, Eric Biggers , dm-devel@redhat.com, Sami Tolvanen , Thomas Gleixner , Alasdair Kergon Subject: Re: [PATCH 0/3] dm-verity: optionally use tasklets in dm-verity Message-ID: References: <20220722093823.4158756-1-nhuck@google.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-kernel@vger.kernel.org On Fri, Jul 22 2022 at 2:12P -0400, Bart Van Assche wrote: > On 7/22/22 09:41, Christoph Hellwig wrote: > > We've been tying to kill off task lets for about 15 years. I don't > > think adding new users will make you a whole lot of friends.. > > +1 for not using tasklets. At least in Android the real-time thread > scheduling latency is important. Tasklets are not visible to the scheduler > and hence cause latency spikes for real-time threads. These latency spikes > can be observed by users, e.g. if the real-time thread is involved in audio > playback. OK, then android wouldn't set the _optional_ "try_verify_in_tasklet" Mike