Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:1 as permitted sender) client-ip=2620:137:e000::3:1;
Date:   Tue, 12 Dec 2023 17:16:15 +0000
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Alexander Potapenko <glider@google.com>
Cc:     will@kernel.org, pcc@google.com, andreyknvl@gmail.com,
        andriy.shevchenko@linux.intel.com, aleksander.lobakin@intel.com,
        linux@rasmusvillemoes.dk, yury.norov@gmail.com,
        alexandru.elisei@arm.com, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, eugenis@google.com,
        syednwaris@gmail.com, william.gray@linaro.org
Subject: Re: [PATCH v9 1/4] arm64: mte: implement CONFIG_ARM64_MTE_COMP
Message-ID: <ZXiVX5FAWZqHfr7m@arm.com>
References: <20231113105234.32058-1-glider@google.com>
 <20231113105234.32058-2-glider@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20231113105234.32058-2-glider@google.com>
Precedence: bulk

On Mon, Nov 13, 2023 at 11:52:30AM +0100, Alexander Potapenko wrote:
> The config implements the algorithm compressing memory tags for ARM MTE
> during swapping.
> 
> The algorithm is based on RLE and specifically targets buffers of tags
> corresponding to a single page. In many cases a buffer can be compressed
> into 63 bits, making it possible to store it without additional memory
> allocation.
> 
> Suggested-by: Evgenii Stepanov <eugenis@google.com>
> Signed-off-by: Alexander Potapenko <glider@google.com>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>

> +void mte_tags_to_ranges(u8 *tags, u8 *out_tags, unsigned short *out_sizes,
> +			size_t *out_len)
> +{
[...]
> +}
> +EXPORT_SYMBOL_NS(mte_tags_to_ranges, MTECOMP);

I may have asked before, what the reason for EXPORT_SYMBOL_NS? Is it for
the kunit tests? Otherwise we don't expect those to be accessed from
modules.

-- 
Catalin