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([2001:288:7001:2703:873:d810:9d97:1c69]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-313c19d1122sm2339081a91.13.2025.06.12.20.34.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Jun 2025 20:34:53 -0700 (PDT) From: I Hsin Cheng To: yury.norov@gmail.com Cc: linux@rasmusvillemoes.dk, jstultz@google.com, tglx@linutronix.de, sboyd@kernel.org, linux-kernel@vger.kernel.org, eleanor15x@gmail.com, visitorckw@gmail.com, jserv@ccns.ncku.edu.tw, skhan@linuxfoundation.org, linux-kernel-mentees@lists.linux.dev, I Hsin Cheng Subject: [RFC PATCH 0/2] Introduce cpumask_first_but() and use cases Date: Fri, 13 Jun 2025 11:34:45 +0800 Message-ID: <20250613033447.3531709-1-richard120310@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel-mentees@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This series introduce cpumask_first_but() and make cpumask_any_but() a wrapper around it, just like other cpumask_any*() helpers, they're some wrappers around cpumask_first*(), except some special cases. The patches are scheduled as the following: 1. The implementation of cpumask_first_but() and some positive results of making cpumask_any_but() a wrapper around it are attached there, including performance and code size. 2. Use cpumask_first_but() in clocksource I Hsin Cheng (2): cpumask: Introduce cpumask_first_but() clocksource: Use cpumask_first_but() in clocksource_verify_choose_cpus() include/linux/cpumask.h | 22 ++++++++++++++++------ kernel/time/clocksource.c | 4 +--- 2 files changed, 17 insertions(+), 9 deletions(-) -- 2.43.0