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Date:   Tue, 12 Dec 2023 17:18:17 +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 4/4] arm64: mte: implement CONFIG_ARM64_MTE_SWAP_STATS
Message-ID: <ZXiV2R-j0_seVp_i@arm.com>
References: <20231113105234.32058-1-glider@google.com>
 <20231113105234.32058-5-glider@google.com>
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On Mon, Nov 13, 2023 at 11:52:33AM +0100, Alexander Potapenko wrote:
> Provide a config to collect the usage statistics for ARM MTE tag
> compression. This patch introduces allocation/deallocation counters
> for buffers that were stored uncompressed (and thus occupy 128 bytes of
> heap plus the Xarray overhead to store a pointer) and those that were
> compressed into 8-byte pointers (effectively using 0 bytes of heap in
> addition to the Xarray overhead).
> 
> The counters are exposed to the userspace via
> /sys/kernel/debug/mteswap/stats:
> 
>   # cat /sys/kernel/debug/mteswap/stats
>   8 bytes:      102496 allocations,     67302 deallocations
>   128 bytes:    212234 allocations,     178278 deallocations
>   uncompressed tag storage size:        8851200
>   compressed tag storage size:  4346368
> 
> Suggested-by: Yury Norov <yury.norov@gmail.com>
> Signed-off-by: Alexander Potapenko <glider@google.com>

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