Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Fri, 23 Jul 2021 15:23:22 +0800
From:   Leo Yan <leo.yan@linaro.org>
To:     "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Mike Leach <mike.leach@linaro.org>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
        coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v4 11/11] perf auxtrace: Add
 compat_auxtrace_mmap__{read_head|write_tail}
Message-ID: <20210723072322.GG179035@leoy-ThinkPad-X240s>
References: <20210711104105.505728-1-leo.yan@linaro.org>
 <20210711104105.505728-12-leo.yan@linaro.org>
 <20210712144410.GE22278@shell.armlinux.org.uk>
 <20210713154602.GD748506@leoy-ThinkPad-X240s>
 <20210713161441.GK22278@shell.armlinux.org.uk>
 <20210713181301.GE13181@arm.com>
 <20210714084015.GM22278@shell.armlinux.org.uk>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210714084015.GM22278@shell.armlinux.org.uk>
Precedence: bulk

On Wed, Jul 14, 2021 at 09:40:15AM +0100, Russell King (Oracle) wrote:
> On Tue, Jul 13, 2021 at 07:13:02PM +0100, Catalin Marinas wrote:
> > We could try to clarify E2.2.1 to simply state that naturally aligned
> > LDRD/STRD are single-copy atomic without any subsequent statement on the
> > translation table.
> 
> I think that clarification would be most helpful. Thanks.

Thanks for the suggestion and confirmation, Russell & Catalin.

If so, I will implement the weak functions for
compat_auxtrace_mmap__{read_head|write_tail}; and write the arm/arm64
specific functions with using LDRD/STRD instructions.

For better patches organization, I will use a separate patch set for
enabling the compat functions (in particular patches 10, 11/11) in
the next spin.

Thanks,
Leo