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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 50AB4C432C3 for ; Fri, 29 Nov 2019 09:13:13 +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 23FA1215A5 for ; Fri, 29 Nov 2019 09:13:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="s6MDANDt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 23FA1215A5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de 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-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ryuvUCDKXN6YEM9kf+KIm4o3MeNU7h2BldUR+sI0sGQ=; b=s6MDANDtXHx4e7 yaIYoEHWjXm8I87evgBLcqJk0RiuyCnFF5aiwrkAKCymyQXcR6GdvNxWHPgnxVXTgRp7grw4QgQDR R5gZtddb1moihfKBCjr6EJLlWg6JcBGVrx5e70AvXqXbv9T/WWioYpaV2efFjcwlIoHP+UlwNG7+e JguAmvVQrdjI03TEMs/Cur2U6lrjIcnWR0rl3VnMj8G8ZSHaGJaq23BC363Zu/o0y98+jV019e37y +t4yfJEumbH5H2f5qRnKhajaFL4zAt+3ztEXem5bUMYcpNNtaSwHFiv1WUm3Akthbrn54EzRG3R9e UnY24nPHQGUjVVor+/CQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iacKq-0004za-Ky; Fri, 29 Nov 2019 09:13:08 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iacKn-0004zC-8F for linux-nvme@lists.infradead.org; Fri, 29 Nov 2019 09:13:07 +0000 Received: from bigeasy by Galois.linutronix.de with local (Exim 4.80) (envelope-from ) id 1iacKk-0001mu-DA; Fri, 29 Nov 2019 10:13:02 +0100 Date: Fri, 29 Nov 2019 10:13:02 +0100 From: Sebastian Andrzej Siewior To: Keith Busch Subject: Re: [PATCH 4/4] nvme/pci: Spin threaded interrupt completions Message-ID: <20191129091302.bngxlcsbexiktqbk@linutronix.de> References: <20191127175824.1929-1-kbusch@kernel.org> <20191127175824.1929-5-kbusch@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191127175824.1929-5-kbusch@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191129_011305_433383_3BD2D185 X-CRM114-Status: UNSURE ( 7.03 ) X-CRM114-Notice: Please train this message. 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: ming.lei@redhat.com, helgaas@kernel.org, hch@lst.de, linux-nvme@lists.infradead.org, sagi@grimberg.me Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 2019-11-28 02:58:24 [+0900], Keith Busch wrote: > diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c > index 571b33b69c5f..9ec0933eb120 100644 > --- a/drivers/nvme/host/pci.c > +++ b/drivers/nvme/host/pci.c > @@ -1042,9 +1042,15 @@ static irqreturn_t nvme_irq(int irq, void *data) > return ret; > } > > +static void nvme_irq_spin(int irq, void *data) > +{ > + while (nvme_irq(irq, data) != IRQ_NONE) > + cond_resched(); > +} That interrupt thread runs at SCHED_FIFO prio 50 by default. You will not get anything with a lower priority running (including SCHED_OTHER). You won't get preempted by another FIFO thread at prio 50 so I *think* that cond_rechsched() won't let you schedule another task/IRQ thread running at prio 50 either. Sebastian _______________________________________________ linux-nvme mailing list linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme