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 A3DFCC4332F for ; Wed, 9 Nov 2022 00:48:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229790AbiKIAsN (ORCPT ); Tue, 8 Nov 2022 19:48:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229744AbiKIAsK (ORCPT ); Tue, 8 Nov 2022 19:48:10 -0500 Received: from mail-qk1-x730.google.com (mail-qk1-x730.google.com [IPv6:2607:f8b0:4864:20::730]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 44422627DD for ; Tue, 8 Nov 2022 16:48:10 -0800 (PST) Received: by mail-qk1-x730.google.com with SMTP id z30so10123304qkz.13 for ; Tue, 08 Nov 2022 16:48:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=+y+o2LSkoAVoMeDy58W+U4Gsq87tRhoJvkciUM9vy6Q=; b=IeATlO0NPnmqR3Scmwmh3SGxr4vyzOEjfr7qlUfaruSmjXxvKBHI6Nxnu1QoG1u21u Gpcq6ywoXYHHaJnu4nmxlWhBfMKdcdnIimMr8VjvmwJoht4cPYmDXAQR/KdxAQxidwl6 jwfDIpE4wY/Ul5rxrmjkY9jaVSNr6S/C/PXZHH/tD/wWL5jX2Yv1xDrdTQ/15X7Hmim/ VK3jznT0WsvofSC912SXQj/8V+QVFc9fnSSXdHwooSWRJDFAbk+P0/h1t176DgrhUydS Lwapch7PYhM6qp00z/+55/xYlvdYJXq1Lngn/Y9MhxmnZoJOU49vl9NMOHpvRjB38tyY KjMQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=+y+o2LSkoAVoMeDy58W+U4Gsq87tRhoJvkciUM9vy6Q=; b=6O3wdBLoj2lFIzf3iAuX/OGbmpx+vadvHOd02ykRem9abUztGY2QrGOuJEvysajDp2 sCizRxUQmz2Ew1mZ4SziGi4EvF14yBHWKtAUCOaCfMKcOmQQKyRYWCb4mmTPFyEBrOgn Gg1eqyBWFVa7nLYOrabFf7J6IY5X3FjZAHy2iCM4E0oo4edlnkP1HVtyccybklwPJjsK BgET7t6T2ZWjsOx1+YrMT/enX/KPLxD2UeHKigegueClJqwPrEfQnJCwy44L3ugm2N1+ 795Id+W9anc76uGZzVMAtYamPnS7Y6XIYR+yTmZP9SzQ1hM+7p39NIQ8FekzPafEgau3 3riA== X-Gm-Message-State: ACrzQf2D/+yuA7QNqEM/Q9Fw0Rt7ZCFy97hatm4pSD0bdyZoqt+JiR+j LccAI3wpBjPR/f1FWxDdRXpEww== X-Google-Smtp-Source: AMsMyM4aMveP3gDx3QDwbE/MjWkJEgbTutW3935X9J26Xvn15mKZ8s+Mswbxqy/r4NtdhmBxLQNERw== X-Received: by 2002:a05:620a:b15:b0:6fa:ae89:dcf8 with SMTP id t21-20020a05620a0b1500b006faae89dcf8mr13452809qkg.266.1667954889424; Tue, 08 Nov 2022 16:48:09 -0800 (PST) Received: from ziepe.ca (hlfxns017vw-47-55-122-23.dhcp-dynamic.fibreop.ns.bellaliant.net. [47.55.122.23]) by smtp.gmail.com with ESMTPSA id fw9-20020a05622a4a8900b003a56d82fd8csm8943337qtb.91.2022.11.08.16.48.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Nov 2022 16:48:08 -0800 (PST) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1osZGC-00HZqg-9N; Tue, 08 Nov 2022 20:48:08 -0400 Date: Tue, 8 Nov 2022 20:48:08 -0400 From: Jason Gunthorpe To: Anthony DeRossi Cc: kvm@vger.kernel.org, alex.williamson@redhat.com, cohuck@redhat.com, kevin.tian@intel.com, abhsahu@nvidia.com, yishaih@nvidia.com Subject: Re: [PATCH v5 2/3] vfio: Export the device set open count Message-ID: References: <20221105224458.8180-1-ajderossi@gmail.com> <20221105224458.8180-3-ajderossi@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221105224458.8180-3-ajderossi@gmail.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sat, Nov 05, 2022 at 03:44:57PM -0700, Anthony DeRossi wrote: > The open count of a device set is the sum of the open counts of all > devices in the set. Drivers can use this value to determine whether > shared resources are in use without tracking them manually or accessing > the private open_count in vfio_device. > > Signed-off-by: Anthony DeRossi > --- > drivers/vfio/vfio_main.c | 11 +++++++++++ > include/linux/vfio.h | 1 + > 2 files changed, 12 insertions(+) > > +unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set) > +{ > + struct vfio_device *cur; > + unsigned int open_count = 0; I'd probably just make this a bool 'vfio_device_set_last_close()' And roll in the < 1 logic too Nothing will ever need to know the number of fds open across the set. But this is fine as written Reviewed-by: Jason Gunthorpe Jason