From nobody Sat Apr 11 03:55:25 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 95519C25B08 for ; Wed, 17 Aug 2022 17:58:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241273AbiHQR6s (ORCPT ); Wed, 17 Aug 2022 13:58:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241107AbiHQR6b (ORCPT ); Wed, 17 Aug 2022 13:58:31 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7AC313E24 for ; Wed, 17 Aug 2022 10:58:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660759108; 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=dgGyeroL7nQdNp4tnXnxYdnkM2nPtV/937q52s3gCa4=; b=KY625oOtisuf+T7aUgO0phHJG9SdiI2+5G7Crj4TsU5WR1LAQxHBLs5I7Rnq6elhBFteuT IHijvx0QtfEp5hhAeQtuZIQ6lcLnv6b0/w+8BwTlRhx7tGFiX/fm1sGaTyups6cA6YiHv4 SKVan8fz3H/5avWZNKR2pXh9WSA5jdc= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-449-Qv_DF0GpOSiLAtwvIOAVXA-1; Wed, 17 Aug 2022 13:58:27 -0400 X-MC-Unique: Qv_DF0GpOSiLAtwvIOAVXA-1 Received: by mail-wm1-f69.google.com with SMTP id b4-20020a05600c4e0400b003a5a96f1756so1413795wmq.0 for ; Wed, 17 Aug 2022 10:58:27 -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=dgGyeroL7nQdNp4tnXnxYdnkM2nPtV/937q52s3gCa4=; b=x+FwLHEzedcggCmUvtT7NdQ8v2ek4QVt2t9hq3i41/0R3GKvamQV/isiFrw7osaFtq g16aZjcequjofFHsOU4H3tzZxbjKQCjy2DyKNC+sVPCIKBVRlRwtaM2xoN58dOEotBp9 0Pb6BiXGIA1TLgU4HV3frxXzwumkCku9nhY8bxWlfome7aQb5jQ5hCvs1FoIRXmJxoV0 eLtEx1XFtmD3xOqhbIO742tmPvYsfoz4MCrL0fGOyln0WJOWRcnI7alMYqxVTaw2ztXM I12SXHdN9jmfhUEZGAtKrA7EIwVYoectO4O5ehQfIJriB4xg6KqlfUORU0ehTg11lzqD pdLA== X-Gm-Message-State: ACgBeo1DtFMZs87Y0cniIXHfkLgJcKa2ecFHCf6RifU78Hxn4nGE+1VD UsU0/eKbFkRE+e8R4WkckN6tzY5gWtOVW64iIiOarShgLC8FNAg9ownSJDK21QrM0Jk8liUwNfD 2CfZLmRE5opHulgU4EaQ66uOf X-Received: by 2002:a1c:7c18:0:b0:3a5:aaae:d203 with SMTP id x24-20020a1c7c18000000b003a5aaaed203mr2944198wmc.2.1660759106078; Wed, 17 Aug 2022 10:58:26 -0700 (PDT) X-Google-Smtp-Source: AA6agR6BuvGaPt3Y8Uq9xyqFkwCoOJ0UWHYzIzHfPTHj9ADsoXRbGLYtizHhA+vtJ3TFF0VSU9wZjQ== X-Received: by 2002:a1c:7c18:0:b0:3a5:aaae:d203 with SMTP id x24-20020a1c7c18000000b003a5aaaed203mr2944172wmc.2.1660759105855; Wed, 17 Aug 2022 10:58:25 -0700 (PDT) Received: from vschneid.remote.csb ([185.11.37.247]) by smtp.gmail.com with ESMTPSA id u8-20020a05600c19c800b003a541d893desm2809009wmq.38.2022.08.17.10.58.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Aug 2022 10:58:25 -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 2/5] cpumask: Introduce for_each_cpu_andnot() Date: Wed, 17 Aug 2022 18:58:09 +0100 Message-Id: <20220817175812.671843-3-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 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 | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 0d435d0edbcb..295b137717bb 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -237,6 +237,25 @@ unsigned int cpumask_next_and(int n, const struct cpum= ask *src1p, nr_cpumask_bits, n + 1); } =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 + */ +static inline +unsigned 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); +} + /** * for_each_cpu - iterate over every cpu in a mask * @cpu: the (optionally unsigned) integer iterator @@ -297,6 +316,25 @@ unsigned int __pure cpumask_next_wrap(int n, const str= uct cpumask *mask, int sta (cpu) =3D cpumask_next_and((cpu), (mask1), (mask2)), \ (cpu) < nr_cpu_ids;) =20 +/** + * for_each_cpu_andnot - iterate over every cpu in one mask but not in the= other + * @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;) + /** * cpumask_any_but - return a "random" in a cpumask, but not this one. * @mask: the cpumask to search --=20 2.31.1