From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 20133330B06; Fri, 17 Oct 2025 15:56:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760716589; cv=none; b=pi6HYafQwRa8A4CHC0bvAzQPdbD2gHyp8ABeO3kRE6996yqyruoLwRTI4ha/p4C84PQRRITq3rC7c+j9f8/BUOC+Y049aw1DSp7JKQ4PBbqWq8DxC3ShLiFfm1NoAhLveJaOCHcXLLrsfJHIqUq8IPdtv1AK4dm5PX2QABlTz5A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760716589; c=relaxed/simple; bh=WVbKPuTkozrrmukC0DFBvdWwFXegxLb6bj8EzCYSFR8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eppMOxpyc1Md5mXxVHwWhmQ7zAzBbonUKRKRUFJZBqBkzIeMPZ/NwDrt63jhYvSNNfhvR+KGNOl0lTIIX1g5m6yidwh5OLUxKEWzyHm/mFiChj3lYOmqosN4UdiguDTY31kfiOFzyZC2uPqHn2lWtf6FmR2X8d6bW24YThI6Ywc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TE3v9Av8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="TE3v9Av8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 98A91C4CEE7; Fri, 17 Oct 2025 15:56:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760716589; bh=WVbKPuTkozrrmukC0DFBvdWwFXegxLb6bj8EzCYSFR8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TE3v9Av8gN8JuIC9FMbWFAkaYdZQ1CqMAVaDR6DC4YnmczzTXJfP5ytjA96k/jM+0 lC2YsZSmqenrGI1NJiq86uTdO1+epxQARs8H/wgagqJoiLfZdgxszGhrZzngFNNgPx 9S/B3mP20coOtFsHL37RcK8pGPTEIx1/lemZCnZs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Herve Codina , Andy Shevchenko , Christophe Leroy , Mark Brown , Eliav Farber Subject: [PATCH 5.15 242/276] minmax: Introduce {min,max}_array() Date: Fri, 17 Oct 2025 16:55:35 +0200 Message-ID: <20251017145151.307428414@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251017145142.382145055@linuxfoundation.org> References: <20251017145142.382145055@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Herve Codina [ Upstream commit c952c748c7a983a8bda9112984e6f2c1f6e441a5 ] Introduce min_array() (resp max_array()) in order to get the minimal (resp maximum) of values present in an array. Signed-off-by: Herve Codina Reviewed-by: Andy Shevchenko Reviewed-by: Christophe Leroy Link: https://lore.kernel.org/r/20230623085830.749991-8-herve.codina@bootlin.com Signed-off-by: Mark Brown Signed-off-by: Eliav Farber Signed-off-by: Greg Kroah-Hartman --- include/linux/minmax.h | 64 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) --- a/include/linux/minmax.h +++ b/include/linux/minmax.h @@ -168,6 +168,70 @@ */ #define max_t(type, x, y) __careful_cmp(max, (type)(x), (type)(y)) +/* + * Remove a const qualifier from integer types + * _Generic(foo, type-name: association, ..., default: association) performs a + * comparison against the foo type (not the qualified type). + * Do not use the const keyword in the type-name as it will not match the + * unqualified type of foo. + */ +#define __unconst_integer_type_cases(type) \ + unsigned type: (unsigned type)0, \ + signed type: (signed type)0 + +#define __unconst_integer_typeof(x) typeof( \ + _Generic((x), \ + char: (char)0, \ + __unconst_integer_type_cases(char), \ + __unconst_integer_type_cases(short), \ + __unconst_integer_type_cases(int), \ + __unconst_integer_type_cases(long), \ + __unconst_integer_type_cases(long long), \ + default: (x))) + +/* + * Do not check the array parameter using __must_be_array(). + * In the following legit use-case where the "array" passed is a simple pointer, + * __must_be_array() will return a failure. + * --- 8< --- + * int *buff + * ... + * min = min_array(buff, nb_items); + * --- 8< --- + * + * The first typeof(&(array)[0]) is needed in order to support arrays of both + * 'int *buff' and 'int buff[N]' types. + * + * The array can be an array of const items. + * typeof() keeps the const qualifier. Use __unconst_integer_typeof() in order + * to discard the const qualifier for the __element variable. + */ +#define __minmax_array(op, array, len) ({ \ + typeof(&(array)[0]) __array = (array); \ + typeof(len) __len = (len); \ + __unconst_integer_typeof(__array[0]) __element = __array[--__len]; \ + while (__len--) \ + __element = op(__element, __array[__len]); \ + __element; }) + +/** + * min_array - return minimum of values present in an array + * @array: array + * @len: array length + * + * Note that @len must not be zero (empty array). + */ +#define min_array(array, len) __minmax_array(min, array, len) + +/** + * max_array - return maximum of values present in an array + * @array: array + * @len: array length + * + * Note that @len must not be zero (empty array). + */ +#define max_array(array, len) __minmax_array(max, array, len) + /** * clamp_t - return a value clamped to a given range using a given type * @type: the type of variable to use