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 8E160C2BB41 for ; Tue, 16 Aug 2022 18:08:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236991AbiHPSIT (ORCPT ); Tue, 16 Aug 2022 14:08:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38304 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236906AbiHPSHw (ORCPT ); Tue, 16 Aug 2022 14:07:52 -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 C6DE885F99 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=1660673261; 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=vH2jTlmzQIwOMeKUkJzPFxzEVFleWwYuNxRt4X4XvAY=; b=cmMQF5MV4d1o0o7Kx/cto+FCxnjN5y5SzJR+UXTMchLIrzS9WKgRjIOdMsM9S7kzSGCkBS 0cRRt8cmORFN451TVgb0FX1O/0aC6DhBdewwexfC1TAgSXgXq4aiAuRevTyAW5/HqlW0Jj OE+F+4axd2QB7ACrgikbFDNgOAXYrm8= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-48-R3ghcE0UM4Obhp3W9NjidA-1; Tue, 16 Aug 2022 14:07:40 -0400 X-MC-Unique: R3ghcE0UM4Obhp3W9NjidA-1 Received: by mail-wm1-f70.google.com with SMTP id a17-20020a05600c349100b003a545125f6eso10552983wmq.4 for ; Tue, 16 Aug 2022 11:07:40 -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=vH2jTlmzQIwOMeKUkJzPFxzEVFleWwYuNxRt4X4XvAY=; b=ebnCaflHtaFr8lmC9EDT837dRnGScu0LpReSgvx85KBr23EDUbIfbYkoXino32crYf vHW1oBUW+x13bYaVswcAj47FT7WQ3hOUx26W3KEkU81AEum8tRNIBazOcu+/1m2j6oSU bTS9pbsYQ5ikeFnMDbPchOn6824+QfcmuAmz81UEMUCTcuTcLbpvAH/BnMvgxsC9SNUB 4U+Oa0FM1PAPS4rN+duLStKv9vPRn+YU0ga4L1oeCdW9x1JkZPFxc/iLjpMNayLx75tS lIso1liZ4IWBpQMmQ55NmuUFRj3b0bw5s43L2gOhYJcESjwHRhRZjeJnFgMEf2SLS+/1 JRgg== X-Gm-Message-State: ACgBeo0u2othLhV/dTf4kSd83Z0M3zPG5pM7kV8SlWUodX9S8G81ys9e 1W2e995R76nqvBzhZjLqqvke/7Ck3lLtnN9jk4HAw1kEl4kOaReq5/o5DAx5JgYc9P+wD8BXmX9 niHWgSwYLESBJTSq/lFUHgik5 X-Received: by 2002:a05:600c:4fcf:b0:3a5:b7f7:3127 with SMTP id o15-20020a05600c4fcf00b003a5b7f73127mr14638611wmq.160.1660673259512; Tue, 16 Aug 2022 11:07:39 -0700 (PDT) X-Google-Smtp-Source: AA6agR6Ozt5n5rw1n8vb1yr16M5RH2dEqwc/tjFIJhySTHC/leYqLbNjdSwNueyR8yo+3ivUTDnsZQ== X-Received: by 2002:a05:600c:4fcf:b0:3a5:b7f7:3127 with SMTP id o15-20020a05600c4fcf00b003a5b7f73127mr14638594wmq.160.1660673259334; Tue, 16 Aug 2022 11:07:39 -0700 (PDT) Received: from vschneid.remote.csb ([185.11.37.247]) by smtp.gmail.com with ESMTPSA id o8-20020a05600c4fc800b003a319bd3278sm14694961wmq.40.2022.08.16.11.07.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Aug 2022 11:07:38 -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 2/5] cpumask: Introduce for_each_cpu_andnot() Date: Tue, 16 Aug 2022 19:07:24 +0100 Message-Id: <20220816180727.387807-3-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" for_each_cpu_and() is very convenient as it saves having to allocate a temporary cpumask to store the result of cpumask_and(). The same issue applies to cpumask_andnot() which doesn't actually need temporary storage for iteration purposes. Following what has been done for for_each_cpu_and(), introduce for_each_cpu_andnot(). Signed-off-by: Valentin Schneider --- include/linux/cpumask.h | 32 ++++++++++++++++++++++++++++++++ lib/cpumask.c | 19 +++++++++++++++++++ 2 files changed, 51 insertions(+) diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index fe29ac7cc469..a8b2ca160e57 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -157,6 +157,13 @@ static inline unsigned int cpumask_next_and(int n, return n+1; } =20 +static inline unsigned int cpumask_next_andnot(int n, + const struct cpumask *srcp, + const struct cpumask *andp) +{ + return n+1; +} + static inline unsigned int cpumask_next_wrap(int n, const struct cpumask *= mask, int start, bool wrap) { @@ -194,6 +201,8 @@ static inline int cpumask_any_distribute(const struct c= pumask *srcp) for ((cpu) =3D 0; (cpu) < 1; (cpu)++, (void)mask, (void)(start)) #define for_each_cpu_and(cpu, mask1, mask2) \ for ((cpu) =3D 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) +#define for_each_cpu_andnot(cpu, mask1, mask2) \ + for ((cpu) =3D 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) #else /** * cpumask_first - get the first cpu in a cpumask @@ -259,6 +268,9 @@ static inline unsigned int cpumask_next_zero(int n, con= st struct cpumask *srcp) } =20 int __pure cpumask_next_and(int n, const struct cpumask *, const struct cp= umask *); +int __pure cpumask_next_andnot(int n, + const struct cpumask *src1p, + const struct cpumask *src2p); int __pure cpumask_any_but(const struct cpumask *mask, unsigned int cpu); unsigned int cpumask_local_spread(unsigned int i, int node); int cpumask_any_and_distribute(const struct cpumask *src1p, @@ -324,6 +336,26 @@ extern int cpumask_next_wrap(int n, const struct cpuma= sk *mask, int start, bool for ((cpu) =3D -1; \ (cpu) =3D cpumask_next_and((cpu), (mask1), (mask2)), \ (cpu) < nr_cpu_ids;) + +/** + * for_each_cpu_andnot - iterate over every cpu in one mask but not in ano= ther + * @cpu: the (optionally unsigned) integer iterator + * @mask1: the first cpumask pointer + * @mask2: the second cpumask pointer + * + * This saves a temporary CPU mask in many places. It is equivalent to: + * struct cpumask tmp; + * cpumask_andnot(&tmp, &mask1, &mask2); + * for_each_cpu(cpu, &tmp) + * ... + * + * After the loop, cpu is >=3D nr_cpu_ids. + */ +#define for_each_cpu_andnot(cpu, mask1, mask2) \ + for ((cpu) =3D -1; \ + (cpu) =3D cpumask_next_andnot((cpu), (mask1), (mask2)), \ + (cpu) < nr_cpu_ids;) + #endif /* SMP */ =20 #define CPU_BITS_NONE \ diff --git a/lib/cpumask.c b/lib/cpumask.c index a971a82d2f43..6896ff4a08fd 100644 --- a/lib/cpumask.c +++ b/lib/cpumask.c @@ -42,6 +42,25 @@ int cpumask_next_and(int n, const struct cpumask *src1p, } EXPORT_SYMBOL(cpumask_next_and); =20 +/** + * cpumask_next_andnot - get the next cpu in *src1p & ~*src2p + * @n: the cpu prior to the place to search (ie. return will be > @n) + * @src1p: the first cpumask pointer + * @src2p: the second cpumask pointer + * + * Returns >=3D nr_cpu_ids if no further cpus set in *src1p & ~*src2p. + */ +int cpumask_next_andnot(int n, const struct cpumask *src1p, + const struct cpumask *src2p) +{ + /* -1 is a legal arg here. */ + if (n !=3D -1) + cpumask_check(n); + return find_next_andnot_bit(cpumask_bits(src1p), cpumask_bits(src2p), + nr_cpumask_bits, n + 1); +} +EXPORT_SYMBOL(cpumask_next_andnot); + /** * cpumask_any_but - return a "random" in a cpumask, but not this one. * @mask: the cpumask to search --=20 2.31.1