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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 7B204C00307 for ; Fri, 6 Sep 2019 18:31:06 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 5415120674 for ; Fri, 6 Sep 2019 18:31:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BboEiXo1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5415120674 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=grimberg.me Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=C4y5+EJRwhWRyIOQmwWtZJB+SeCKNG8nd6AUpkZdaMU=; b=BboEiXo1exxmr+7lvj1E4A6kT R70l68+Lny0UgZCNGfE2HM/4sj57TkMgUsULo5ojDy6z7GF91Y+6+GT8Zk3Wer260UHlYcAY5dvuy m6J3WoQJvzJ6/ic7OLjOQX/n6HkFIHbf2Q6QTc1c1bI4kQvp2MC7OioDibGW0jj45qb8CTur+CWzj VuLpj04p55G+Ao0NjCDWYOWB/4/erL8i262gfmx2SB2j8ZJeKmpGVB8D/m8IxLJWLq6rfaRsswIb3 pQNyBX8tq12qjURzATPHbaKtnR2q9NCU69zJiyNfNLUXDEeQfyBR2NeGWBFVmmeipbjNzIwFsYScl Jg+RVaopQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i6J0i-0000DJ-RP; Fri, 06 Sep 2019 18:31:05 +0000 Received: from mail-ot1-f66.google.com ([209.85.210.66]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1i6J0f-0000Cr-Kg for linux-nvme@lists.infradead.org; Fri, 06 Sep 2019 18:31:02 +0000 Received: by mail-ot1-f66.google.com with SMTP id b2so6581705otq.10 for ; Fri, 06 Sep 2019 11:31:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=inlyOQUAj9IgrEa/tTn6FC+PgqOBuK2w0K+3C9jmY5A=; b=k4VaiSjj1704QPjwLNZsQvq86jUhHgm5+/TLIoQ4kfngm4VU2uSBmjB6LE7fs7/9p6 BWdX6nbg0eOaTU958vruUK4XrO7WZMCFnrjxoeWO52kOihitYNvqzFn+VwBWO9JwAF4H q2NjlcWjPYTzjt09gty1q94ROQnNijkQ9JfxfRzZyHl53chvLP7W/G2RphciuRKYo3li rUCHxfI5UM7vEwOYf9gSmpruMWbyQ7IB5WSqsEb3re7ECHIOJNDISGWMSj0zTwZfgJSh VuaZ3PrB2qphxV/YRYanQI7XDd+EDR/vUXSw+OJQB99qM/pAMD+XT4Q/FuSniPnEmM+P xXKQ== X-Gm-Message-State: APjAAAVOYiTX4hUEXi6sDj5eabQZJEUCjn//5YLlCXdrVdFKzaaeMrg0 TFNrduCTde0UjB+yw53x2y0= X-Google-Smtp-Source: APXvYqxWAkAjBw9LI0HQBqKJ+CxguDMlNik/iXtNNjR5JA1VPQ+boOZQ7WXXD7Me44XzHY7PgXFxsw== X-Received: by 2002:a9d:66d2:: with SMTP id t18mr8790061otm.355.1567794660729; Fri, 06 Sep 2019 11:31:00 -0700 (PDT) Received: from ?IPv6:2600:1700:65a0:78e0:514:7862:1503:8e4d? ([2600:1700:65a0:78e0:514:7862:1503:8e4d]) by smtp.gmail.com with ESMTPSA id t30sm1086635otj.40.2019.09.06.11.30.58 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Sep 2019 11:30:59 -0700 (PDT) Subject: Re: [PATCH 1/4] softirq: implement IRQ flood detection mechanism To: Daniel Lezcano , Ming Lei References: <20190903033001.GB23861@ming.t460p> <299fb6b5-d414-2e71-1dd2-9d6e34ee1c79@linaro.org> <20190903063125.GA21022@ming.t460p> <6b88719c-782a-4a63-db9f-bf62734a7874@linaro.org> <20190903072848.GA22170@ming.t460p> <6f3b6557-1767-8c80-f786-1ea667179b39@acm.org> <2a8bd278-5384-d82f-c09b-4fce236d2d95@linaro.org> <20190905090617.GB4432@ming.t460p> <6a36ccc7-24cd-1d92-fef1-2c5e0f798c36@linaro.org> <20190906014819.GB27116@ming.t460p> From: Sagi Grimberg Message-ID: <6eb2a745-7b92-73ce-46f5-cc6a5ef08abc@grimberg.me> Date: Fri, 6 Sep 2019 11:30:57 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190906_113101_682410_9374B0E4 X-CRM114-Status: GOOD ( 12.66 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Keith Busch , Hannes Reinecke , Bart Van Assche , linux-scsi@vger.kernel.org, Peter Zijlstra , Long Li , John Garry , LKML , linux-nvme@lists.infradead.org, Jens Axboe , Ingo Molnar , Thomas Gleixner , Christoph Hellwig Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org > > Ok, so the real problem is per-cpu bounded tasks. > > I share Thomas opinion about a NAPI like approach. We already have that, its irq_poll, but it seems that for this use-case, we get lower performance for some reason. I'm not entirely sure why that is, maybe its because we need to mask interrupts because we don't have an "arm" register in nvme like network devices have? _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme