From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <stable-bounces@dpdk.org>
Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124])
	by inbox.dpdk.org (Postfix) with ESMTP id 26B2C43F1A
	for <public@inbox.dpdk.org>; Fri, 26 Apr 2024 17:41:53 +0200 (CEST)
Received: from mails.dpdk.org (localhost [127.0.0.1])
	by mails.dpdk.org (Postfix) with ESMTP id 1573943EEF;
	Fri, 26 Apr 2024 17:41:53 +0200 (CEST)
Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182])
 by mails.dpdk.org (Postfix) with ESMTP id 8A18A43D7A;
 Fri, 26 Apr 2024 17:41:50 +0200 (CEST)
Received: by linux.microsoft.com (Postfix, from userid 1086)
 id CD3D4210EF24; Fri, 26 Apr 2024 08:41:49 -0700 (PDT)
DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com CD3D4210EF24
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com;
 s=default; t=1714146109;
 bh=lvKx2qLJWmhXvw01TR0v1rdQbfEtSHyce/dvRy4dsjY=;
 h=Date:From:To:Cc:Subject:References:In-Reply-To:From;
 b=rHYhpbETw7rJUidjyy0PaDcmZNS4WuGL9FhMNmVZrnHglfLMyS7OKQNPd+FJDZ5Kk
 G+CVqKFQaNHdGfZOBHDVe9XO2Qn8Nz77xESErOwM/rep70npznmr3EfbC7SYYFyYiG
 VzrP/LzU0HTiPt/dpnqUXyekpycd+t1oUcytt+34=
Date: Fri, 26 Apr 2024 08:41:49 -0700
From: Tyler Retzlaff <roretzla@linux.microsoft.com>
To: Mattias =?iso-8859-1?Q?R=F6nnblom?= <mattias.ronnblom@ericsson.com>
Cc: dev@dpdk.org, hofors@lysator.liu.se,
 Morten =?iso-8859-1?Q?Br=F8rup?= <mb@smartsharesystems.com>,
 Stephen Hemminger <stephen@networkplumber.org>,
 Thomas Monjalon <thomas@monjalon.net>,
 "John W . Linville" <linville@tuxdriver.com>,
 Ferruh Yigit <ferruh.yigit@amd.com>, stable@dpdk.org
Subject: Re: [PATCH v3] net/af_packet: cache align Rx/Tx structs
Message-ID: <20240426154149.GA27008@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net>
References: <20240426073824.100386-1-mattias.ronnblom@ericsson.com>
 <20240426090502.100487-1-mattias.ronnblom@ericsson.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20240426090502.100487-1-mattias.ronnblom@ericsson.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
X-BeenThere: stable@dpdk.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: patches for DPDK stable branches <stable.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/stable>,
 <mailto:stable-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/stable/>
List-Post: <mailto:stable@dpdk.org>
List-Help: <mailto:stable-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/stable>,
 <mailto:stable-request@dpdk.org?subject=subscribe>
Errors-To: stable-bounces@dpdk.org

On Fri, Apr 26, 2024 at 11:05:02AM +0200, Mattias Rönnblom wrote:
> Cache align Rx and Tx queue struct to avoid false sharing.
> 
> The RX struct happens to be 64 bytes on x86_64 already, so cache
> alignment has no effect there, but it does on 32-bit ISAs.
> 
> The TX struct is 56 bytes on x86_64.
> 
> Both structs keep counters, and in the RX case they are updated even
> for empty polls.
> 
> v3: Move __rte_cache_aligned directive to a MSVC-compatible location.
> 
> Fixes: 364e08f2bbc0 ("af_packet: add PMD for AF_PACKET-based virtual devices")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
> ---
Acked-by: Tyler Retzlaff <roretzla@linux.microsoft.com>