From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7E8AC7112B for ; Fri, 18 Aug 2023 06:30:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357178AbjHRG2f (ORCPT ); Fri, 18 Aug 2023 02:28:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358062AbjHRG20 (ORCPT ); Fri, 18 Aug 2023 02:28:26 -0400 Received: from mail-lf1-x136.google.com (mail-lf1-x136.google.com [IPv6:2a00:1450:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0725C10C0 for ; Thu, 17 Aug 2023 23:28:25 -0700 (PDT) Received: by mail-lf1-x136.google.com with SMTP id 2adb3069b0e04-4ff9abf18f9so717213e87.2 for ; Thu, 17 Aug 2023 23:28:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rasmusvillemoes.dk; s=google; t=1692340103; x=1692944903; h=content-transfer-encoding:in-reply-to:from:content-language :references:to:subject:user-agent:mime-version:date:message-id:from :to:cc:subject:date:message-id:reply-to; bh=0YFcn5NgIiAMz1+cp7pg/nNSy+7Fusx4SPkjE7L2z70=; b=atag02lcLBGejuN/J52tITP0cad0+IJrmkpQ574vQmlScX5Y0bNMfISD4FSu835R6O gVSxFz/qvXR+hnfBYvcFIDLd0D2qwOUK6mcQny3TuLlikStcqa1yuGauyTwYTVZcU727 VvR6Ls1+lyqaYROHvi3Kxo4+hb5GtrGkKqt+E= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692340103; x=1692944903; h=content-transfer-encoding:in-reply-to:from:content-language :references:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0YFcn5NgIiAMz1+cp7pg/nNSy+7Fusx4SPkjE7L2z70=; b=KG6y2TAAiZv5Repku26E2wUpoymCskX3feLZshAHVbNUIJnZmTYPq2b7n9FQnCP0gs r4gV+oClS/EGFmXMWlR1Qah6ZsSWTTL8l3MWHZU3idIsQ7x4aPPCSs2Lv1Y2g3o6N1Y1 cK6C+zdHAc2igmnvuc0shXzuQErpby1ssvoIoquxxAJlrE/2nv59VZ4LMYeoNJ2wfpH4 Q8XzYl3wsMztxp824oi/QwUZsUBQUSB0lo7Hjy5PjgVgHw6HP83qBPsacsAtzqc1fPBT /A1cefEa11G7bt4hw5nc3llOetikSWf/oj1ZvIB15j4GvCt7c7fWAiN5HzGxN/k6O32N almw== X-Gm-Message-State: AOJu0YxvgPPcQSzztNkglTYdZmI68ZBfiqQNZIK+sbYo/NJh6UGI4viU 814WzUMPzpw+6c4iuyW521G7GxBDln5QCEv59dFDkw== X-Google-Smtp-Source: AGHT+IFlg6snHAv0mgq0MX8xYqANu7Err9yyTx8iOMhmTw7i/hjqyTxfrG76Jx4fTvqGptUGVjHhjg== X-Received: by 2002:a05:6512:3e02:b0:4ff:745b:4f1f with SMTP id i2-20020a0565123e0200b004ff745b4f1fmr1243862lfv.30.1692340102762; Thu, 17 Aug 2023 23:28:22 -0700 (PDT) Received: from [172.16.11.116] ([81.216.59.226]) by smtp.gmail.com with ESMTPSA id v10-20020ac2592a000000b004fe47b88defsm200882lfi.138.2023.08.17.23.28.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 17 Aug 2023 23:28:22 -0700 (PDT) Message-ID: <26fc3fb7-eb68-e5ff-ec86-67982734491e@rasmusvillemoes.dk> Date: Fri, 18 Aug 2023 08:28:21 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH v1 1/2] bitmap: Use constants and macros from bits.h To: Andy Shevchenko , Yury Norov , linux-kernel@vger.kernel.org References: <20230817165453.713353-1-andriy.shevchenko@linux.intel.com> <20230817165453.713353-2-andriy.shevchenko@linux.intel.com> Content-Language: en-US, da From: Rasmus Villemoes In-Reply-To: <20230817165453.713353-2-andriy.shevchenko@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17/08/2023 18.54, Andy Shevchenko wrote: > Use BITS_PER_LONG and BITS_PER_BYTE for BITMAP_MEM_ALIGNMENT. > Calculate bytes from bits for memcmp() and memset() with BITS_TO_BYTES(). > > Signed-off-by: Andy Shevchenko > --- > include/linux/bitmap.h | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h > index 1516ff979315..2d5042d1b501 100644 > --- a/include/linux/bitmap.h > +++ b/include/linux/bitmap.h > @@ -354,9 +354,9 @@ static inline void bitmap_complement(unsigned long *dst, const unsigned long *sr > } > > #ifdef __LITTLE_ENDIAN > -#define BITMAP_MEM_ALIGNMENT 8 > +#define BITMAP_MEM_ALIGNMENT BITS_PER_BYTE > #else > -#define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long)) > +#define BITMAP_MEM_ALIGNMENT BITS_PER_LONG > #endif > #define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1) > > @@ -367,7 +367,7 @@ static inline bool bitmap_equal(const unsigned long *src1, > return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); > if (__builtin_constant_p(nbits & BITMAP_MEM_MASK) && > IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) > - return !memcmp(src1, src2, nbits / 8); > + return !memcmp(src1, src2, BITS_TO_BYTES(nbits)); Please no. Currently, I can verify the arithmetic directly. Using such a "helper" I'd have to know whether it just does /8 or if it's more like the bitmap_words() thing which rounds up to a whole number of words. And BITS_PER_BYTE (and similarly CHAR_BITS) really is, IMO, much less readable than 8. Rasmus