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 DF3BCA0546; Wed, 7 Apr 2021 10:26:18 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id A221C141096; Wed, 7 Apr 2021 10:26:18 +0200 (CEST) Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by mails.dpdk.org (Postfix) with ESMTP id BFFAE141088 for ; Wed, 7 Apr 2021 10:26:16 +0200 (CEST) Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.nyi.internal (Postfix) with ESMTP id 23B295C012C; Wed, 7 Apr 2021 04:26:16 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Wed, 07 Apr 2021 04:26:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=fm3; bh= a/zJOBe63JoVOrIg1TgQ/qaa+kQHZKr6Evj6pkTlTXg=; b=XJRZkNgchLirLPEh qM5EEXVs7z1/ATy7RsrDPn/6i1FOKlawJJP62fG/w6oePskuVr4sqW7ZMub8HJgO Eds3e9VdOVN2U7WGu2H0qxS1O02YjuT1siVtPwvihRWW6H/qqdnn6A6XyE1JPaig MXMnMFYJDQhDT/84pCqdXUom/Zhjyp0jXFMhFr//WE0LClgKqCwALDgB5uQxEfrH f0lRKO63wzcLp8y2JQa8iBKcJ+WpQfPLJGwu+IdcgSEh/yVUn5JzpT8ABsLBoIaY BlGVocHjy9LLTdGou03I3ZxUDNXHO55lKhHFiv+P7Dk08gYNlmyeI+sWRfG3s8ij j6VN9w== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm2; bh=a/zJOBe63JoVOrIg1TgQ/qaa+kQHZKr6Evj6pkTlT Xg=; b=ATy3OHSxDyJ6nbsgfGfYBwQvNvEJyOgb3Lx6q/PaQcjgx/Z+bvhTahGak hd1lw4ZmCwnHWPCKTr8ATH/ARZwdKEKflUypguEi+oCQvfkXEH/n+CexKVPWu+ia R03pdHUiEaKBn4bVeZU9in8F+9HQa5vTfXqXOODi8wXYeLBYlH+an56BWuTOZ9bl TIMqTyVEagAzV0eLRCyv5t8AjXv1quMnDQEYcUYt8dPvUNJmTIWnBM5HBdZe5utC W2JL62QdezBUzrNIgR4KeNZliprJsJNwYSgiPIlS80KLCLpA/dG21L0W1Bk6vo/Q 3FRy+i2xNA1JuX/DxETmugMt5HfHQ== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledrudejjedgtdegucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhephffvufffkfgjfhgggfgtsehtufertddttddvnecuhfhrohhmpefvhhhomhgr shcuofhonhhjrghlohhnuceothhhohhmrghssehmohhnjhgrlhhonhdrnhgvtheqnecugg ftrfgrthhtvghrnhepudeggfdvfeduffdtfeeglefghfeukefgfffhueejtdetuedtjeeu ieeivdffgeehnecukfhppeejjedrudefgedrvddtfedrudekgeenucevlhhushhtvghruf hiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehthhhomhgrshesmhhonhhjrghl ohhnrdhnvght X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA id 3FF531080066; Wed, 7 Apr 2021 04:26:14 -0400 (EDT) From: Thomas Monjalon To: Cheng Jiang , Maxime Coquelin , bruce.richardson@intel.com Cc: chenbo.xia@intel.com, dev@dpdk.org, jiayu.hu@intel.com, yvonnex.yang@intel.com, yinan.wang@intel.com, alexr@nvidia.com, shahafs@nvidia.com Date: Wed, 07 Apr 2021 10:26:12 +0200 Message-ID: <2267082.chWHW8dCnR@thomas> In-Reply-To: <23c4f6e7-4895-44b7-4ff0-3a02f9f3f86a@redhat.com> References: <20210317054054.34616-1-Cheng1.jiang@intel.com> <23c4f6e7-4895-44b7-4ff0-3a02f9f3f86a@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [PATCH] examples/vhost: fix ioat ring space in callbacks 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" 07/04/2021 09:47, Maxime Coquelin: > > On 3/17/21 6:40 AM, Cheng Jiang wrote: > > We use ioat ring space for determining if ioat callbacks can enqueue a > > packet to ioat device. But there is one slot can't be used in ioat > > ring due to the ioat driver design, so we need to reduce one slot in > > ioat ring to prevent ring size mismatch in ioat callbacks. > > > > Fixes: 2aa47e94bfb2 ("examples/vhost: add ioat ring space count and check") > > Cc: stable@dpdk.org > > > > Signed-off-by: Cheng Jiang > > --- > > examples/vhost/ioat.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/examples/vhost/ioat.c b/examples/vhost/ioat.c > > index 60b73be93..9cb5e0d50 100644 > > --- a/examples/vhost/ioat.c > > +++ b/examples/vhost/ioat.c > > @@ -113,7 +113,7 @@ open_ioat(const char *value) > > goto out; > > } > > rte_rawdev_start(dev_id); > > - cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE; > > + cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE - 1; > > That really comforts me in thinking we need a generic abstraction for > DMA devices. How is the application developer supposed to know that > the DMA driver has such weird limitations? Having a generic DMA API may be interesting. Do you know any other HW candidate for such an API? Do you think rte_memcpy can be used as a SW driver?