[PATCH 06/14] cpumask: re-introduce cpumask_next{,_and}_wrap()

Yury Norov
2024-12-28T18:50:05Z

cpumask_next_wrap_old() has two additional parameters, comparing to it's
analogue in linux/find.h find_next_bit_wrap(). The reason for that is
historical.

Before 4fe49b3b97c262 ("lib/bitmap: introduce for_each_set_bit_wrap()
macro"), cpumask_next_wrap() was used to implement for_each_cpu_wrap()
iterator. Now that the iterator is an alias to generic
for_each_set_bit_wrap(), the additional parameters aren't used and may
confuse readers.

All existing users call cpumask_next_wrap() in a way that makes it
possible to turn it to straight and simple alias to find_next_bit_wrap().

In a couple places kernel users opencode missing cpumask_next_and_wrap().
Add it as well.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
include/linux/cpumask.h | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)

diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index b267a4f6a917..18c9908d50c4 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -284,6 +284,43 @@ unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
small_cpumask_bits, n + 1);
}

+/**
+ * cpumask_next_and_wrap - get the next cpu in *src1p & *src2p, starting from
+ * @n and wrapping around, if needed
+ * @n: the cpu prior to the place to search (i.e. return will be > @n)
+ * @src1p: the first cpumask pointer
+ * @src2p: the second cpumask pointer
+ *
+ * Return: >= nr_cpu_ids if no further cpus set in both.
+ */
+static __always_inline
+unsigned int cpumask_next_and_wrap(int n, const struct cpumask *src1p,
+ const struct cpumask *src2p)
+{
+ /* -1 is a legal arg here. */
+ if (n != -1)
+ cpumask_check(n);
+ return find_next_and_bit_wrap(cpumask_bits(src1p), cpumask_bits(src2p),
+ small_cpumask_bits, n + 1);
+}
+
+/*
+ * cpumask_next_wrap - get the next cpu in *src, starting from
+ * @n and wrapping around, if needed
+ * @n: the cpu prior to the place to search
+ * @src: cpumask pointer
+ *
+ * Return: >= nr_cpu_ids if no further cpus set in both.
+ */
+static __always_inline
+unsigned int cpumask_next_wrap(int n, const struct cpumask *src)
+{
+ /* -1 is a legal arg here. */
+ if (n != -1)
+ cpumask_check(n);
+ return find_next_bit_wrap(cpumask_bits(src), small_cpumask_bits, n + 1);
+}
+
/**
* for_each_cpu - iterate over every cpu in a mask
* @cpu: the (optionally unsigned) integer iterator
--
2.43.0