From patchwork Fri Nov 11 04:00:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yury Norov X-Patchwork-Id: 13039607 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 7BC85C43217 for ; Fri, 11 Nov 2022 04:00:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232446AbiKKEAf (ORCPT ); Thu, 10 Nov 2022 23:00:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232080AbiKKEAd (ORCPT ); Thu, 10 Nov 2022 23:00:33 -0500 Received: from mail-oa1-x36.google.com (mail-oa1-x36.google.com [IPv6:2001:4860:4864:20::36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA524663D0; Thu, 10 Nov 2022 20:00:32 -0800 (PST) Received: by mail-oa1-x36.google.com with SMTP id 586e51a60fabf-13b103a3e5dso4339761fac.2; Thu, 10 Nov 2022 20:00:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=MPqmuncXUCU3pW/zVD2ThZ+OJwOyZGXsie5WSsI5Oh8=; b=d7kNbAR+XN+55Y78lTPX/AcgKjBIcFtiVfpbHNR6fGXUjfu0fc6N5DgXL0DPt0FOsG mImOMTGRKD058s5Opn/bS8AP/Ww/c2LPjMT2PYTrDGhjnHCSAp+roN4qibzTOjOjCEFx zXEm7Rs8i3yogDI2kcQcd3yTmA/g+QL12Zknka3omfARYd79Es/iCaqA0kfl84XXl+/m 3GnoRBJHtStYrnBhiN/D2SFQbxYhTNMKe/Bmnp0GHiX6G6zpmM8DHhrNg4vDGqkxfRpj Ld6pUw90Am+U6cuVRt4OMLMHWKe6hExyLLvuobAhWSQnOOKnFVLiMu/Zd8adV/WnXASP dHgQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=MPqmuncXUCU3pW/zVD2ThZ+OJwOyZGXsie5WSsI5Oh8=; b=LXLjKKtYaoZ3X0vpEeYmHUPYrZihFSffQMpG40M6CioxC67Ogqm9LCpBFcA/r/gYA+ LP3wHxEGoL+4CJ0UcHQhxzhCunGADeMNUIAGu4eTExgmW/KDc1opU/9aL4p8xTDuaCnz H6w5hcNhsUJKRpYvpA0moVgLgABQt6oV8FpWEU4HwzrpiG/jEEa+Q5ZnfG9GF5zjYcWg BEMyIxWl3FmXkQNhK5q+B00YINIsgvDGj88o6/G6+vV7lV/9U6pxxkoGMe4KhBEZAz0i M3KS9D5OZX1Pw7MTrw0+7z1J+GLFVf8ZbvnGKXPB5jBCU9Prveg4nCod56+qTgdp+NJs 5vGQ== X-Gm-Message-State: ACrzQf2GYqg8VUfTSvYQr/Dge62q/67Ld86OCr9OtB6eJVHyiqeTOIj8 nk+VAsCuOt8mHAM01qIcaDcXUqUREac= X-Google-Smtp-Source: AMsMyM5Xsoo+HsbznS0m+wxPjY7H0NY3MsBKTiqPr4ytUF/Dly2hgMuLkd3Ju98TPQvPZZnrk5VooA== X-Received: by 2002:a05:6870:c98a:b0:13b:a8de:c248 with SMTP id hi10-20020a056870c98a00b0013ba8dec248mr2928387oab.99.1668139231805; Thu, 10 Nov 2022 20:00:31 -0800 (PST) Received: from localhost ([12.97.180.36]) by smtp.gmail.com with ESMTPSA id c18-20020a4ac312000000b0049be423151asm435717ooq.34.2022.11.10.20.00.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Nov 2022 20:00:31 -0800 (PST) From: Yury Norov To: linux-kernel@vger.kernel.org, "David S. Miller" , Andy Shevchenko , Barry Song , Ben Segall , Daniel Bristot de Oliveira , Dietmar Eggemann , Gal Pressman , Greg Kroah-Hartman , Heiko Carstens , Ingo Molnar , Jakub Kicinski , Jason Gunthorpe , Jesse Brandeburg , Jonathan Cameron , Juri Lelli , Leon Romanovsky , Mel Gorman , Peter Zijlstra , Rasmus Villemoes , Saeed Mahameed , Steven Rostedt , Tariq Toukan , Tariq Toukan , Tony Luck , Valentin Schneider , Vincent Guittot Cc: Yury Norov , linux-crypto@vger.kernel.org, netdev@vger.kernel.org, linux-rdma@vger.kernel.org Subject: [PATCH 1/4] lib/find: introduce find_nth_and_andnot_bit Date: Thu, 10 Nov 2022 20:00:24 -0800 Message-Id: <20221111040027.621646-2-yury.norov@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221111040027.621646-1-yury.norov@gmail.com> References: <20221111040027.621646-1-yury.norov@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org The function is used to implement in-place bitmaps traversing without storing intermediate result in temporary bitmaps, in the following patches. Signed-off-by: Yury Norov --- include/linux/find.h | 33 +++++++++++++++++++++++++++++++++ lib/find_bit.c | 9 +++++++++ 2 files changed, 42 insertions(+) diff --git a/include/linux/find.h b/include/linux/find.h index ccaf61a0f5fd..7a97b492b447 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -22,6 +22,9 @@ unsigned long __find_nth_and_bit(const unsigned long *addr1, const unsigned long unsigned long size, unsigned long n); unsigned long __find_nth_andnot_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long size, unsigned long n); +unsigned long __find_nth_and_andnot_bit(const unsigned long *addr1, const unsigned long *addr2, + const unsigned long *addr3, unsigned long size, + unsigned long n); extern unsigned long _find_first_and_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long size); extern unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size); @@ -255,6 +258,36 @@ unsigned long find_nth_andnot_bit(const unsigned long *addr1, const unsigned lon return __find_nth_andnot_bit(addr1, addr2, size, n); } +/** + * find_nth_and_andnot_bit - find N'th set bit in 2 memory regions, + * excluding those set in 3rd region + * @addr1: The 1st address to start the search at + * @addr2: The 2nd address to start the search at + * @addr3: The 3rd address to start the search at + * @size: The maximum number of bits to search + * @n: The number of set bit, which position is needed, counting from 0 + * + * Returns the bit number of the N'th set bit. + * If no such, returns @size. + */ +static inline +unsigned long find_nth_and_andnot_bit(const unsigned long *addr1, + const unsigned long *addr2, + const unsigned long *addr3, + unsigned long size, unsigned long n) +{ + if (n >= size) + return size; + + if (small_const_nbits(size)) { + unsigned long val = *addr1 & *addr2 & (~*addr2) & GENMASK(size - 1, 0); + + return val ? fns(val, n) : size; + } + + return __find_nth_and_andnot_bit(addr1, addr2, addr3, size, n); +} + #ifndef find_first_and_bit /** * find_first_and_bit - find the first set bit in both memory regions diff --git a/lib/find_bit.c b/lib/find_bit.c index 18bc0a7ac8ee..c10920e66788 100644 --- a/lib/find_bit.c +++ b/lib/find_bit.c @@ -155,6 +155,15 @@ unsigned long __find_nth_andnot_bit(const unsigned long *addr1, const unsigned l } EXPORT_SYMBOL(__find_nth_andnot_bit); +unsigned long __find_nth_and_andnot_bit(const unsigned long *addr1, + const unsigned long *addr2, + const unsigned long *addr3, + unsigned long size, unsigned long n) +{ + return FIND_NTH_BIT(addr1[idx] & addr2[idx] & ~addr3[idx], size, n); +} +EXPORT_SYMBOL(__find_nth_and_andnot_bit); + #ifndef find_next_and_bit unsigned long _find_next_and_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long nbits, unsigned long start)