From patchwork Wed Aug 17 17:58:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Schneider X-Patchwork-Id: 12946285 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 CD3BCC32771 for ; Wed, 17 Aug 2022 17:58:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240992AbiHQR6g (ORCPT ); Wed, 17 Aug 2022 13:58:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240842AbiHQR6b (ORCPT ); Wed, 17 Aug 2022 13:58:31 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63682255BD for ; Wed, 17 Aug 2022 10:58:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660759107; 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=FeC1hIbpeF331EYBQF/yk4Lw5Xn8tjgBYGOWKQGB6dY=; b=H65DNSX434viksn7/bLCbXgNMFZ/vGwfPptAIN8pCMWB8z4fNTTs+HjkHYtLWtMUGfCjgU Hp1wAFFXs59WscNK00t4fvGa+OMmKQl+fKdxRrTVmMSEHWC/BOBs3gcfks2QyjovKILeuS J0ov/M1JPjC+FMjLAULfhR/Rro+dWH0= 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-378-98p6Fi6RMz2coT1h28EK3w-1; Wed, 17 Aug 2022 13:58:26 -0400 X-MC-Unique: 98p6Fi6RMz2coT1h28EK3w-1 Received: by mail-wm1-f71.google.com with SMTP id a17-20020a05600c349100b003a545125f6eso1390738wmq.4 for ; Wed, 17 Aug 2022 10:58:25 -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=FeC1hIbpeF331EYBQF/yk4Lw5Xn8tjgBYGOWKQGB6dY=; b=kZWJXT6b/huJQ2pY+2Vaq8mw7hXKabpVMMWwGVEhQO8VHbB6tmeZ4iNIrwxz3eVr09 YQs+Z3Mvst4LycBrerFEekigFZswlw7JMz5skeKgAWojeat7lg1hnul9XIyBfjZP+6zD TlOUqGQHoYZmnwYaSuOQUCTJbIARtA2C6PRNdRtdSMTx1xaPmdhFTjmBux8UlwOzQtM4 k5fVbZFTS3hhFNKJBMRYwsN6MlaX/Chr3mS1E4KXr9bnPAJNCWDb/AQxej81iZEicQvG pMOhpvOT4jvMZZ6Fbja16dn+4dF5V56dOJR2JMhYbXbH+A57HMe8tluZe5doJ3Htlm5M FnFg== X-Gm-Message-State: ACgBeo2txYh6zwngdSI2McT4PYsye5WvS6r/ru4uWHWdxnsAyjPrfPzc NCg49KnCOaJBh/M2lDk2NqDMEY1ANy9FQXSw0tO85mD7TZkoFhXFmz9EzXFdSyykT5pVBoAIY8i KfDN9XUqeOlA8yDvPBjSoTSsAZaFDf7bYJ7IUWXlRi1Ing/RTxv2V2oZtDNe5x5qROqtd X-Received: by 2002:a05:600c:4ece:b0:3a6:28:bc59 with SMTP id g14-20020a05600c4ece00b003a60028bc59mr2841890wmq.154.1660759104429; Wed, 17 Aug 2022 10:58:24 -0700 (PDT) X-Google-Smtp-Source: AA6agR510plnN0HC3OB3lvW09uzTiD8Mi1hIvWoOCu1vCuuNhK8JvlAqdM5qXlzOkhVL+R6kqbyikQ== X-Received: by 2002:a05:600c:4ece:b0:3a6:28:bc59 with SMTP id g14-20020a05600c4ece00b003a60028bc59mr2841852wmq.154.1660759104030; Wed, 17 Aug 2022 10:58:24 -0700 (PDT) Received: from vschneid.remote.csb ([185.11.37.247]) by smtp.gmail.com with ESMTPSA id u8-20020a05600c19c800b003a541d893desm2809009wmq.38.2022.08.17.10.58.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Aug 2022 10:58:23 -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 v2 1/5] bitops: Introduce find_next_andnot_bit() Date: Wed, 17 Aug 2022 18:58:08 +0100 Message-Id: <20220817175812.671843-2-vschneid@redhat.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220817175812.671843-1-vschneid@redhat.com> References: <20220817175812.671843-1-vschneid@redhat.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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. Note that the _find_next_bit() @invert argument now gets split into two: @invert1 for words in @addr1, @invert2 for words in @addr2. The only current users of _find_next_bit() with @invert set are: o find_next_zero_bit() o find_next_zero_bit_le() and neither of these pass an @addr2, so the conversion is straightforward. Signed-off-by: Valentin Schneider --- include/linux/find.h | 44 ++++++++++++++++++++++++++++++++++++++------ lib/find_bit.c | 23 ++++++++++++----------- 2 files changed, 50 insertions(+), 17 deletions(-) diff --git a/include/linux/find.h b/include/linux/find.h index 424ef67d4a42..920597de4e62 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -10,7 +10,8 @@ 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 invert1, unsigned long invert2, + unsigned long le); extern unsigned long _find_first_bit(const unsigned long *addr, unsigned long 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, unsigned long size, return val ? __ffs(val) : size; } - return _find_next_bit(addr, NULL, size, offset, 0UL, 0); + return _find_next_bit(addr, NULL, size, offset, 0UL, 0UL, 0); } #endif @@ -71,7 +72,38 @@ unsigned long find_next_and_bit(const unsigned long *addr1, return val ? __ffs(val) : size; } - return _find_next_bit(addr1, addr2, size, offset, 0UL, 0); + return _find_next_bit(addr1, addr2, size, offset, 0UL, 0UL, 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 >= size)) + return size; + + val = *addr1 & ~*addr2 & GENMASK(size - 1, offset); + return val ? __ffs(val) : size; + } + + return _find_next_bit(addr1, addr2, size, offset, 0UL, ~0UL, 0); } #endif @@ -99,7 +131,7 @@ unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, return val == ~0UL ? size : ffz(val); } - return _find_next_bit(addr, NULL, size, offset, ~0UL, 0); + return _find_next_bit(addr, NULL, size, offset, ~0UL, 0UL, 0); } #endif @@ -247,7 +279,7 @@ unsigned long find_next_zero_bit_le(const void *addr, unsigned return val == ~0UL ? size : ffz(val); } - return _find_next_bit(addr, NULL, size, offset, ~0UL, 1); + return _find_next_bit(addr, NULL, size, offset, ~0UL, 0UL, 1); } #endif @@ -266,7 +298,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned return val ? __ffs(val) : size; } - return _find_next_bit(addr, NULL, size, offset, 0UL, 1); + return _find_next_bit(addr, NULL, size, offset, 0UL, 0UL, 1); } #endif diff --git a/lib/find_bit.c b/lib/find_bit.c index 1b8e4b2a9cba..c46b66d7d2b4 100644 --- a/lib/find_bit.c +++ b/lib/find_bit.c @@ -21,27 +21,29 @@ #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 "invert" arguments, which are XORed with each fetched word (invert1 + * for words in addr1, invert2 for those in addr2) before searching it for + * one bits. */ 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) + const unsigned long *addr2, + unsigned long nbits, unsigned long start, + unsigned long invert1, unsigned long invert2, + unsigned long le) { unsigned long tmp, mask; if (unlikely(start >= nbits)) return nbits; - tmp = addr1[start / BITS_PER_LONG]; + tmp = addr1[start / BITS_PER_LONG] ^ invert1; if (addr2) - tmp &= addr2[start / BITS_PER_LONG]; - tmp ^= invert; + tmp &= addr2[start / BITS_PER_LONG] ^ invert2; /* Handle 1st word. */ mask = BITMAP_FIRST_WORD_MASK(start); @@ -57,10 +59,9 @@ unsigned long _find_next_bit(const unsigned long *addr1, if (start >= nbits) return nbits; - tmp = addr1[start / BITS_PER_LONG]; + tmp = addr1[start / BITS_PER_LONG] ^ invert1; if (addr2) - tmp &= addr2[start / BITS_PER_LONG]; - tmp ^= invert; + tmp &= addr2[start / BITS_PER_LONG] ^ invert2; } if (le)