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=-5.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 465FFC06511 for ; Wed, 3 Jul 2019 07:24:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A6D721882 for ; Wed, 3 Jul 2019 07:24:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562138662; bh=oKLiX+noAGMAX3ZpKVTLVn9b2ZYDuHOziGSU1+gstKU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ObZVCG+lXpXw259Nk417TdnR9SGZopGiGcniv3Q8Shf9vkI+CJspsnRBenSbxaK9A 2FgneE6+bRnySIDpRg0YV8GLcMmK+sAp7QZW81yqGdHo2+936yV+t7X9kUhpNmMpTz B/pjeypUD/5/3zCRBph6CkrVVs4nWKPFNykehdx0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727285AbfGCHYU (ORCPT ); Wed, 3 Jul 2019 03:24:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:42376 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726327AbfGCHYU (ORCPT ); Wed, 3 Jul 2019 03:24:20 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D2DB321881; Wed, 3 Jul 2019 07:24:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562138659; bh=oKLiX+noAGMAX3ZpKVTLVn9b2ZYDuHOziGSU1+gstKU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rLh+yYfz/nRaPHeiqDg1glKx2Cy7AtwWnvYxbfuMNcfK/3479K8YaolFNL6iG88uI es8AkxUt8kfHyiJ7ZeDugjBOxhcT2XdH2URPgNC+NYOxXbSatRdLqXMuwESPtDbM/b AuKCcRQ/T+sE5VamnY7oazoPR3EFPjSYuHPfRTJw= Date: Wed, 3 Jul 2019 09:24:16 +0200 From: Greg Kroah-Hartman To: Sasha Levin Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Daniel Borkmann , Jean-Philippe Brucker , Will Deacon , Alexei Starovoitov Subject: Re: [PATCH 5.1 51/55] bpf, arm64: use more scalable stadd over ldxr / stxr loop in xadd Message-ID: <20190703072416.GD3033@kroah.com> References: <20190702080124.103022729@linuxfoundation.org> <20190702080126.728030225@linuxfoundation.org> <20190703020200.GR11506@sasha-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190703020200.GR11506@sasha-vm> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 02, 2019 at 10:02:00PM -0400, Sasha Levin wrote: > On Tue, Jul 02, 2019 at 10:01:59AM +0200, Greg Kroah-Hartman wrote: > > From: Daniel Borkmann > > > > commit 34b8ab091f9ef57a2bb3c8c8359a0a03a8abf2f9 upstream. > > > > Since ARMv8.1 supplement introduced LSE atomic instructions back in 2016, > > lets add support for STADD and use that in favor of LDXR / STXR loop for > > the XADD mapping if available. STADD is encoded as an alias for LDADD with > > XZR as the destination register, therefore add LDADD to the instruction > > encoder along with STADD as special case and use it in the JIT for CPUs > > that advertise LSE atomics in CPUID register. If immediate offset in the > > BPF XADD insn is 0, then use dst register directly instead of temporary > > one. > > > > Signed-off-by: Daniel Borkmann > > Acked-by: Jean-Philippe Brucker > > Acked-by: Will Deacon > > Signed-off-by: Alexei Starovoitov > > Signed-off-by: Greg Kroah-Hartman > > This one has a fix upstream: c5e2edeb01ae9ffbdde95bdcdb6d3614ba1eb195 > ("arm64: insn: Fix ldadd instruction encoding"). Good catch, now queued up, thanks. greg k-h