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From: Yury Norov <yury.norov@gmail.com>
To: linux-kernel@vger.kernel.org,
	"Yury Norov [NVIDIA]" <yury.norov@gmail.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	John Stultz <jstultz@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Stephen Boyd <sboyd@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH v3 2/3] cpumask: introduce cpumask_random()
Date: Tue, 17 Jun 2025 16:08:52 -0400	[thread overview]
Message-ID: <20250617200854.60753-3-yury.norov@gmail.com> (raw)
In-Reply-To: <20250617200854.60753-1-yury.norov@gmail.com>

From: "Yury Norov [NVIDIA]" <yury.norov@gmail.com>

Propagate find_random_bit() to cpumask API.

Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
---
 include/linux/cpumask.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index 7ae80a7ca81e..39b71b662da3 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -354,6 +354,18 @@ unsigned int cpumask_next_wrap(int n, const struct cpumask *src)
 	return find_next_bit_wrap(cpumask_bits(src), small_cpumask_bits, n + 1);
 }
 
+/**
+ * cpumask_random - get random cpu in *src.
+ * @src: cpumask pointer
+ *
+ * Return: random set bit, or >= nr_cpu_ids if @src is empty.
+ */
+static __always_inline
+unsigned int cpumask_random(const struct cpumask *src)
+{
+	return find_random_bit(cpumask_bits(src), nr_cpu_ids);
+}
+
 /**
  * for_each_cpu - iterate over every cpu in a mask
  * @cpu: the (optionally unsigned) integer iterator
-- 
2.43.0


  parent reply	other threads:[~2025-06-17 20:09 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-17 20:08 [PATCH v3 0/3] bitmap: introduce find_random_bit() and use in clocksource Yury Norov
2025-06-17 20:08 ` [PATCH v3 1/3] bitmap: generalize node_random() Yury Norov
2025-06-17 22:50   ` Andrew Morton
2025-06-17 22:59     ` Yury Norov
2025-06-17 20:08 ` Yury Norov [this message]
2025-06-17 20:08 ` [PATCH v3 3/3] clocksource: Improve randomness in clocksource_verify_choose_cpus() Yury Norov

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