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References: <20211005065948.10092-1-mark-pk.tsai@mediatek.com> <163425869104.1688384.2477307279117424281@swboyd.mtv.corp.google.com>
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From:   Chen-Yu Tsai <wenst@chromium.org>
Date:   Mon, 18 Oct 2021 11:38:26 +0800
Message-ID: <CAGXv+5HM07is85SyBEQ07TbvpAsi72qYJXtFEsyFcK2WSO=SsA@mail.gmail.com>
Subject: Re: [PATCH] clk: make clk_core_lookup faster by using clk name hash
To:     Stephen Boyd <sboyd@kernel.org>
Cc:     Mark-PK Tsai <mark-pk.tsai@mediatek.com>,
        Michael Turquette <mturquette@baylibre.com>,
        yj.chiang@mediatek.com, Matthias Brugger <matthias.bgg@gmail.com>,
        linux-clk <linux-clk@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
        <linux-arm-kernel@lists.infradead.org>,
        "moderated list:ARM/Mediatek SoC support" 
        <linux-mediatek@lists.infradead.org>
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On Fri, Oct 15, 2021 at 8:44 AM Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting Mark-PK Tsai (2021-10-04 23:59:49)
> > Compare hash value before strcmp the full name to make
> > clk_core_lookup faster.
> >
> > It make clk driver probe 30 percent faster on the platform
> > have 1483 registered clks and average clock name length 20.
>
> Why is clk_core_lookup() a fast path for you?

Maybe because the Mediatek clock driver still does global clk name matching
to resolve parents?