From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 6682AA00C2; Wed, 17 Mar 2021 11:27:02 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id D45FE140F85; Wed, 17 Mar 2021 11:27:01 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by mails.dpdk.org (Postfix) with ESMTP id 2BE5E4069F for ; Wed, 17 Mar 2021 11:26:59 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615976819; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vW5gA/40Lm7LalT3x5RG4lS6qgQJeUtZhnH6O1fTY1I=; b=ApFCpW6K84HkK6ZJSd0JJg4b3pW4Vp6DKajjLgVJ3TyQzC23oJiWwO1rBgf9u4W0AIAiQO jHYVjS2iwR1EXCPsP9MdgT5w7bpwFb8v6IUx+mkLZJFIzlAboZy+H9IWKgozgcHBt2k4cu C+RK9DZmH2EQmuzuEE4tbcvgJFxfRS0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-593-eo94bt-OPc-ecZ_3mIxVig-1; Wed, 17 Mar 2021 06:26:57 -0400 X-MC-Unique: eo94bt-OPc-ecZ_3mIxVig-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 53EC71009446; Wed, 17 Mar 2021 10:26:56 +0000 (UTC) Received: from [10.36.110.14] (unknown [10.36.110.14]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 370E460CCE; Wed, 17 Mar 2021 10:26:51 +0000 (UTC) To: David Marchand Cc: dev , "Xia, Chenbo" , Adrian Moreno Zapata , Olivier Matz , bnemeth@redhat.com References: <20210316124153.503928-1-maxime.coquelin@redhat.com> <20210316124153.503928-4-maxime.coquelin@redhat.com> From: Maxime Coquelin Message-ID: Date: Wed, 17 Mar 2021 11:26:49 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=maxime.coquelin@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 3/16/21 2:38 PM, David Marchand wrote: > On Tue, Mar 16, 2021 at 1:42 PM Maxime Coquelin > wrote: >> >> This patch moves vhost_virtuqueue struct fields in order > > virtqueue > You might want to add something in your local dictionary :-p. > > >> to both optimize packing and move hot fields on the first >> cachelines. >> >> Signed-off-by: Maxime Coquelin >> --- >> lib/librte_vhost/vhost.h | 52 +++++++++++++++++++++------------------- >> 1 file changed, 27 insertions(+), 25 deletions(-) >> >> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h >> index 3a71dfeed9..ae45b05dd1 100644 >> --- a/lib/librte_vhost/vhost.h >> +++ b/lib/librte_vhost/vhost.h >> @@ -133,7 +133,7 @@ struct vhost_virtqueue { >> struct vring_used *used; >> struct vring_packed_desc_event *device_event; >> }; >> - uint32_t size; >> + uint16_t size; > > There is one site in the code that could be problematic: > > vhost_user_set_vring_num() > ... > vq->size = msg->payload.state.num; > ... > if (vq->size > 32768) { > > payload.state.num is an unsigned int, so we'd better check its value > as an unsigned int, before storing to vq->size. Indeed, I will rework the function, so that it checks that msg->payload.state.num is smaller than 32K to comply with the spec, and so remove the later check on vq->size. > >> >> uint16_t last_avail_idx; >> uint16_t last_used_idx; >> @@ -143,29 +143,12 @@ struct vhost_virtqueue { >> #define VIRTIO_INVALID_EVENTFD (-1) >> #define VIRTIO_UNINITIALIZED_EVENTFD (-2) >> >> - int enabled; >> - int access_ok; >> - int ready; >> - int notif_enable; >> -#define VIRTIO_UNINITIALIZED_NOTIF (-1) >> + bool enabled; >> + bool access_ok; >> + bool ready; > > Changing those types is fine, but it is a bit odd to still see > boolean_var = 0 or boolean_var = 1 in the rest of the code. Yes, I fix all the places with assigning boolean values. > >> >> rte_spinlock_t access_lock; >> >> - /* Used to notify the guest (trigger interrupt) */ >> - int callfd; >> - /* Currently unused as polling mode is enabled */ >> - int kickfd; >> - >> - /* Physical address of used ring, for logging */ >> - uint64_t log_guest_addr; >> - >> - /* inflight share memory info */ >> - union { >> - struct rte_vhost_inflight_info_split *inflight_split; >> - struct rte_vhost_inflight_info_packed *inflight_packed; >> - }; >> - struct rte_vhost_resubmit_info *resubmit_inflight; >> - uint64_t global_counter; >> >> union { >> struct vring_used_elem *shadow_used_split; >> @@ -176,22 +159,36 @@ struct vhost_virtqueue { >> uint16_t shadow_aligned_idx; >> /* Record packed ring first dequeue desc index */ >> uint16_t shadow_last_used_idx; >> - struct vhost_vring_addr ring_addrs; >> >> - struct batch_copy_elem *batch_copy_elems; >> uint16_t batch_copy_nb_elems; >> + struct batch_copy_elem *batch_copy_elems; >> bool used_wrap_counter; >> bool avail_wrap_counter; >> >> - struct log_cache_entry *log_cache; >> + /* Physical address of used ring, for logging */ >> uint16_t log_cache_nb_elem; > > Indent is broken / not consistent, probably because you cut/pasted lines. Will fix it. Thanks, Maxime