From nobody Sat Apr 11 03:54:32 2026 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 7BEBBC32773 for ; Tue, 16 Aug 2022 18:08:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237001AbiHPSIX (ORCPT ); Tue, 16 Aug 2022 14:08:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236859AbiHPSHx (ORCPT ); Tue, 16 Aug 2022 14:07:53 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6BEC85A93 for ; Tue, 16 Aug 2022 11:07:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660673260; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=HtzANJkF3fIKBG6pDjj83ztNrPxfzq+9oZeNYsNNuu8=; b=cmdKwSYy+8LcCi8BFbVzMR1/bAcyS+Kr9db9mdSJgzo0VNXu8sBw9YaEut/nwajIc+2HY2 +eZhCwKjCbuGlvcxGkIwuQQH6NFFdABkp/GNRKaRiw4XdhylEvwyelHs68TPp2uoKJkcvT jz8bs1giHvc1uzQj2cHWaaxpcI6UsYA= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-177-POw_DprmOXKh4LJflHbH6w-1; Tue, 16 Aug 2022 14:07:39 -0400 X-MC-Unique: POw_DprmOXKh4LJflHbH6w-1 Received: by mail-wm1-f71.google.com with SMTP id c66-20020a1c3545000000b003a5f6dd6a25so2848631wma.1 for ; Tue, 16 Aug 2022 11:07:39 -0700 (PDT) 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; bh=HtzANJkF3fIKBG6pDjj83ztNrPxfzq+9oZeNYsNNuu8=; b=Bmrv2RNT0ifBwSoYsF8FBqc+ITeQ5tukUyYBRxX9+p+ag5VCg5UOwp2Ae/KgmCuZPl eemS325/fy9WvvWap5feQasSNlO9NKCHsg/Zb9ndol4X5Jooj490TlmD6dZtHpBZYZqv VnuOIvMSAOmc68S+sMQsoPjGoXczM6lv/BgQs55YwKI1qPQgA2kdQswip9wSvwuDUV6H 1n/Tq5a95N9kdKAGJThvV9NLXDqpRjRTIGlienFyD2IZ4C0WtUlqJm97n9M9H1ZkCRKJ a6sF2iwQXx3EXTEQ6PbNyraUW2FtfeJWbnq5MKGoE+8ydkhfnpkrtN80Stqyh9G+dOOI 1V2g== X-Gm-Message-State: ACgBeo15kjCXJ9hjLD1wF0AvP9qrt5dBSCDZmjLQxPkktHTfBhrePUr1 idwnEei1Ar8fl2RcKD0Ghqpf150Py4vQU9GGqueh41s0wyl2uFKByrrAw+KvkbcXLQR7JpNWf/C zvfjsOsI3QhwG4eFvoAbM2LgT X-Received: by 2002:a05:600c:1c95:b0:3a5:c28a:df3e with SMTP id k21-20020a05600c1c9500b003a5c28adf3emr14330691wms.40.1660673258197; Tue, 16 Aug 2022 11:07:38 -0700 (PDT) X-Google-Smtp-Source: AA6agR7tWq3rhhkG9Yu7hBK0MmyUQOoH650N5a09JOyFV+MGIy/P/ZBBA1Gd0v6ZG1BSPs9ecxa4Yg== X-Received: by 2002:a05:600c:1c95:b0:3a5:c28a:df3e with SMTP id k21-20020a05600c1c9500b003a5c28adf3emr14330656wms.40.1660673257933; Tue, 16 Aug 2022 11:07:37 -0700 (PDT) Received: from vschneid.remote.csb ([185.11.37.247]) by smtp.gmail.com with ESMTPSA id o8-20020a05600c4fc800b003a319bd3278sm14694961wmq.40.2022.08.16.11.07.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Aug 2022 11:07:37 -0700 (PDT) From: Valentin Schneider To: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Saeed Mahameed , Leon Romanovsky , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Yury Norov , Andy Shevchenko , Rasmus Villemoes , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Mel Gorman , Greg Kroah-Hartman , Barry Song , Heiko Carstens , Tony Luck , Jonathan Cameron , Gal Pressman , Tariq Toukan Subject: [PATCH 1/5] bitops: Introduce find_next_andnot_bit() Date: Tue, 16 Aug 2022 19:07:23 +0100 Message-Id: <20220816180727.387807-2-vschneid@redhat.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220816180727.387807-1-vschneid@redhat.com> References: <20220816180727.387807-1-vschneid@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In preparation of introducing for_each_cpu_andnot(), add a variant of find_next_bit() that negate the bits in @addr2 when ANDing them with the bits in @addr1. Signed-off-by: Valentin Schneider --- include/linux/find.h | 44 ++++++++++++++++++++++++++++++++++++++------ lib/find_bit.c | 16 +++++++++++----- 2 files changed, 49 insertions(+), 11 deletions(-) diff --git a/include/linux/find.h b/include/linux/find.h index 424ef67d4a42..454cde69b30b 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -10,7 +10,8 @@ =20 extern unsigned long _find_next_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long nbits, - unsigned long start, unsigned long invert, unsigned long le); + unsigned long start, unsigned long invert, unsigned long le, + bool negate); extern unsigned long _find_first_bit(const unsigned long *addr, unsigned l= ong size); extern unsigned long _find_first_and_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long size); @@ -41,7 +42,7 @@ unsigned long find_next_bit(const unsigned long *addr, un= signed long size, return val ? __ffs(val) : size; } =20 - return _find_next_bit(addr, NULL, size, offset, 0UL, 0); + return _find_next_bit(addr, NULL, size, offset, 0UL, 0, 0); } #endif =20 @@ -71,7 +72,38 @@ unsigned long find_next_and_bit(const unsigned long *add= r1, return val ? __ffs(val) : size; } =20 - return _find_next_bit(addr1, addr2, size, offset, 0UL, 0); + return _find_next_bit(addr1, addr2, size, offset, 0UL, 0, 0); +} +#endif + +#ifndef find_next_andnot_bit +/** + * find_next_andnot_bit - find the next set bit in one memory region + * but not in the other + * @addr1: The first address to base the search on + * @addr2: The second address to base the search on + * @size: The bitmap size in bits + * @offset: The bitnumber to start searching at + * + * Returns the bit number for the next set bit + * If no bits are set, returns @size. + */ +static inline +unsigned long find_next_andnot_bit(const unsigned long *addr1, + const unsigned long *addr2, unsigned long size, + unsigned long offset) +{ + if (small_const_nbits(size)) { + unsigned long val; + + if (unlikely(offset >=3D size)) + return size; + + val =3D *addr1 & ~*addr2 & GENMASK(size - 1, offset); + return val ? __ffs(val) : size; + } + + return _find_next_bit(addr1, addr2, size, offset, 0UL, 0, 1); } #endif =20 @@ -99,7 +131,7 @@ unsigned long find_next_zero_bit(const unsigned long *ad= dr, unsigned long size, return val =3D=3D ~0UL ? size : ffz(val); } =20 - return _find_next_bit(addr, NULL, size, offset, ~0UL, 0); + return _find_next_bit(addr, NULL, size, offset, ~0UL, 0, 0); } #endif =20 @@ -247,7 +279,7 @@ unsigned long find_next_zero_bit_le(const void *addr, u= nsigned return val =3D=3D ~0UL ? size : ffz(val); } =20 - return _find_next_bit(addr, NULL, size, offset, ~0UL, 1); + return _find_next_bit(addr, NULL, size, offset, ~0UL, 1, 0); } #endif =20 @@ -266,7 +298,7 @@ unsigned long find_next_bit_le(const void *addr, unsign= ed return val ? __ffs(val) : size; } =20 - return _find_next_bit(addr, NULL, size, offset, 0UL, 1); + return _find_next_bit(addr, NULL, size, offset, 0UL, 1, 0); } #endif =20 diff --git a/lib/find_bit.c b/lib/find_bit.c index 1b8e4b2a9cba..6e5f42c621a9 100644 --- a/lib/find_bit.c +++ b/lib/find_bit.c @@ -21,17 +21,19 @@ =20 #if !defined(find_next_bit) || !defined(find_next_zero_bit) || \ !defined(find_next_bit_le) || !defined(find_next_zero_bit_le) || \ - !defined(find_next_and_bit) + !defined(find_next_and_bit) || !defined(find_next_andnot_bit) /* * This is a common helper function for find_next_bit, find_next_zero_bit,= and * find_next_and_bit. The differences are: * - The "invert" argument, which is XORed with each fetched word before * searching it for one bits. - * - The optional "addr2", which is anded with "addr1" if present. + * - The optional "addr2", negated if "negate" and ANDed with "addr1" if + * present. */ unsigned long _find_next_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long nbits, - unsigned long start, unsigned long invert, unsigned long le) + unsigned long start, unsigned long invert, unsigned long le, + bool negate) { unsigned long tmp, mask; =20 @@ -40,7 +42,9 @@ unsigned long _find_next_bit(const unsigned long *addr1, =20 tmp =3D addr1[start / BITS_PER_LONG]; if (addr2) - tmp &=3D addr2[start / BITS_PER_LONG]; + tmp &=3D negate ? + ~addr2[start / BITS_PER_LONG] : + addr2[start / BITS_PER_LONG]; tmp ^=3D invert; =20 /* Handle 1st word. */ @@ -59,7 +63,9 @@ unsigned long _find_next_bit(const unsigned long *addr1, =20 tmp =3D addr1[start / BITS_PER_LONG]; if (addr2) - tmp &=3D addr2[start / BITS_PER_LONG]; + tmp &=3D negate ? + ~addr2[start / BITS_PER_LONG] : + addr2[start / BITS_PER_LONG]; tmp ^=3D invert; } =20 --=20 2.31.1