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[209.132.180.67]) by mx.google.com with ESMTP id z10si11005978edd.140.2019.10.14.00.28.56; Mon, 14 Oct 2019 00:29:20 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=QAeR6xlI; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729264AbfJNH1j (ORCPT + 99 others); Mon, 14 Oct 2019 03:27:39 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:37344 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728941AbfJNH1j (ORCPT ); Mon, 14 Oct 2019 03:27:39 -0400 Received: by mail-wr1-f65.google.com with SMTP id p14so18361040wro.4 for ; Mon, 14 Oct 2019 00:27:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=Lsu4fhje736plADrPfFak7Hyuvi8ToLdp9rnCK4hwgE=; b=QAeR6xlIwruriMfHuFp2cv0YcQ7dfUCPQKWO3lSStColxpeElXzjO1pIuQnkS1TUZN cty42z8g8KK99VaGUqB/ZKPZqONUVjGeeKHaO7U/ZeaPF/37YP+WnTh+wZVEllLcTG7w JQWbBUZoVWjxcHApwBnUGZGGLTX9yOvDPZDrs9WfgOL76QsRx9nGg4GgBGDJNp7H0VNL ndbPJ0Tv48BYDmb3RoNgWP2uo3DBciF1dy4MU724NcdBreSG4GtL9V6VplxrcEZdM5bi d5sPeIPQDBqskiN+LDOq4H1eHwwsSO34kxUg/hgSYldiDuEN2bNCl0bBPIeHsn8M84kI c+ZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=Lsu4fhje736plADrPfFak7Hyuvi8ToLdp9rnCK4hwgE=; b=Iu7fl9HOrH6Qpff7CrL/GRekyVPOsasiGtWzoteJ2c3wHIiANVv9glxKv/5gEFjiZ0 3G69LCwakF+SCCoTDjVFYCxbeV/SqjGgXHvN+Z9vEcsZwRS2UiJOJfyu3P92bKHOBe/g XT88P6byJQP+UjO7TDB+h+LEOa+Z6A4qfIpG2qFXvAvmvEulcyjxqWHphVS0UVqxKo94 WR50UQCicCWM03s+mv0DO4p97YPYNv2oddkq0Q4Kfny8gPM38krXui+c96U43Hr13a9s W0iMBcAmmXDfLM4BOShHkxflJl5ApRpXnlPIxnKObHuWZhRHwaiB5f9P/XUbq+7Fv8+1 VIRA== X-Gm-Message-State: APjAAAUq71ziR7mnJyTbEw+qe+RstWi87L5UY90zb+ItBNWDUfStMoes uhACJveTOUgUlh5fDnDoj3QJyZ5ncWk= X-Received: by 2002:adf:e705:: with SMTP id c5mr23614156wrm.375.1571038056779; Mon, 14 Oct 2019 00:27:36 -0700 (PDT) Received: from dell ([2.27.167.11]) by smtp.gmail.com with ESMTPSA id f20sm14187442wmb.6.2019.10.14.00.27.36 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 14 Oct 2019 00:27:36 -0700 (PDT) Date: Mon, 14 Oct 2019 08:27:34 +0100 From: Lee Jones To: Rasmus Villemoes Cc: Thierry Reding , Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , Daniel Thompson , Jingoo Han , Bartlomiej Zolnierkiewicz , linux-pwm@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/4] backlight: pwm_bl: drop use of int_pow() Message-ID: <20191014072734.GG4545@dell> References: <20191008120327.24208-1-linux@rasmusvillemoes.dk> <20191008120327.24208-4-linux@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20191008120327.24208-4-linux@rasmusvillemoes.dk> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 08 Oct 2019, Rasmus Villemoes wrote: > For a fixed small exponent of 3, it is more efficient to simply use > two explicit multiplications rather than calling the int_pow() library > function: Aside from the function call overhead, its implementation > using repeated squaring means it ends up doing four 64x64 > multiplications. > > Reviewed-by: Daniel Thompson > Signed-off-by: Rasmus Villemoes > --- > drivers/video/backlight/pwm_bl.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) Applied, thanks. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog