Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 199 insertions, 0 deletions

diff --git a/lib/cpumask.c b/lib/cpumask.c
new file mode 100644
index 0000000000..a7fd02b5ae
--- /dev/null
+++ b/lib/cpumask.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/cpumask.h>
+#include <linux/export.h>
+#include <linux/memblock.h>
+#include <linux/numa.h>
+
+/**
+ * cpumask_next_wrap - helper to implement for_each_cpu_wrap
+ * @n: the cpu prior to the place to search
+ * @mask: the cpumask pointer
+ * @start: the start point of the iteration
+ * @wrap: assume @n crossing @start terminates the iteration
+ *
+ * Returns >= nr_cpu_ids on completion
+ *
+ * Note: the @wrap argument is required for the start condition when
+ * we cannot assume @start is set in @mask.
+ */
+unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
+{
+	unsigned int next;
+
+again:
+	next = cpumask_next(n, mask);
+
+	if (wrap && n < start && next >= start) {
+		return nr_cpumask_bits;
+
+	} else if (next >= nr_cpumask_bits) {
+		wrap = true;
+		n = -1;
+		goto again;
+	}
+
+	return next;
+}
+EXPORT_SYMBOL(cpumask_next_wrap);
+
+/* These are not inline because of header tangles. */
+#ifdef CONFIG_CPUMASK_OFFSTACK
+/**
+ * alloc_cpumask_var_node - allocate a struct cpumask on a given node
+ * @mask: pointer to cpumask_var_t where the cpumask is returned
+ * @flags: GFP_ flags
+ * @node: memory node from which to allocate or %NUMA_NO_NODE
+ *
+ * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
+ * a nop returning a constant 1 (in <linux/cpumask.h>)
+ * Returns TRUE if memory allocation succeeded, FALSE otherwise.
+ *
+ * In addition, mask will be NULL if this fails.  Note that gcc is
+ * usually smart enough to know that mask can never be NULL if
+ * CONFIG_CPUMASK_OFFSTACK=n, so does code elimination in that case
+ * too.
+ */
+bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
+{
+	*mask = kmalloc_node(cpumask_size(), flags, node);
+
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+	if (!*mask) {
+		printk(KERN_ERR "=> alloc_cpumask_var: failed!\n");
+		dump_stack();
+	}
+#endif
+
+	return *mask != NULL;
+}
+EXPORT_SYMBOL(alloc_cpumask_var_node);
+
+/**
+ * alloc_bootmem_cpumask_var - allocate a struct cpumask from the bootmem arena.
+ * @mask: pointer to cpumask_var_t where the cpumask is returned
+ *
+ * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
+ * a nop (in <linux/cpumask.h>).
+ * Either returns an allocated (zero-filled) cpumask, or causes the
+ * system to panic.
+ */
+void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask)
+{
+	*mask = memblock_alloc(cpumask_size(), SMP_CACHE_BYTES);
+	if (!*mask)
+		panic("%s: Failed to allocate %u bytes\n", __func__,
+		      cpumask_size());
+}
+
+/**
+ * free_cpumask_var - frees memory allocated for a struct cpumask.
+ * @mask: cpumask to free
+ *
+ * This is safe on a NULL mask.
+ */
+void free_cpumask_var(cpumask_var_t mask)
+{
+	kfree(mask);
+}
+EXPORT_SYMBOL(free_cpumask_var);
+
+/**
+ * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var
+ * @mask: cpumask to free
+ */
+void __init free_bootmem_cpumask_var(cpumask_var_t mask)
+{
+	memblock_free(mask, cpumask_size());
+}
+#endif
+
+/**
+ * cpumask_local_spread - select the i'th cpu based on NUMA distances
+ * @i: index number
+ * @node: local numa_node
+ *
+ * Returns online CPU according to a numa aware policy; local cpus are returned
+ * first, followed by non-local ones, then it wraps around.
+ *
+ * For those who wants to enumerate all CPUs based on their NUMA distances,
+ * i.e. call this function in a loop, like:
+ *
+ * for (i = 0; i < num_online_cpus(); i++) {
+ *	cpu = cpumask_local_spread(i, node);
+ *	do_something(cpu);
+ * }
+ *
+ * There's a better alternative based on for_each()-like iterators:
+ *
+ *	for_each_numa_hop_mask(mask, node) {
+ *		for_each_cpu_andnot(cpu, mask, prev)
+ *			do_something(cpu);
+ *		prev = mask;
+ *	}
+ *
+ * It's simpler and more verbose than above. Complexity of iterator-based
+ * enumeration is O(sched_domains_numa_levels * nr_cpu_ids), while
+ * cpumask_local_spread() when called for each cpu is
+ * O(sched_domains_numa_levels * nr_cpu_ids * log(nr_cpu_ids)).
+ */
+unsigned int cpumask_local_spread(unsigned int i, int node)
+{
+	unsigned int cpu;
+
+	/* Wrap: we always want a cpu. */
+	i %= num_online_cpus();
+
+	cpu = (node == NUMA_NO_NODE) ?
+		cpumask_nth(i, cpu_online_mask) :
+		sched_numa_find_nth_cpu(cpu_online_mask, i, node);
+
+	WARN_ON(cpu >= nr_cpu_ids);
+	return cpu;
+}
+EXPORT_SYMBOL(cpumask_local_spread);
+
+static DEFINE_PER_CPU(int, distribute_cpu_mask_prev);
+
+/**
+ * cpumask_any_and_distribute - Return an arbitrary cpu within src1p & src2p.
+ * @src1p: first &cpumask for intersection
+ * @src2p: second &cpumask for intersection
+ *
+ * Iterated calls using the same srcp1 and srcp2 will be distributed within
+ * their intersection.
+ *
+ * Returns >= nr_cpu_ids if the intersection is empty.
+ */
+unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
+			       const struct cpumask *src2p)
+{
+	unsigned int next, prev;
+
+	/* NOTE: our first selection will skip 0. */
+	prev = __this_cpu_read(distribute_cpu_mask_prev);
+
+	next = find_next_and_bit_wrap(cpumask_bits(src1p), cpumask_bits(src2p),
+					nr_cpumask_bits, prev + 1);
+	if (next < nr_cpu_ids)
+		__this_cpu_write(distribute_cpu_mask_prev, next);
+
+	return next;
+}
+EXPORT_SYMBOL(cpumask_any_and_distribute);
+
+unsigned int cpumask_any_distribute(const struct cpumask *srcp)
+{
+	unsigned int next, prev;
+
+	/* NOTE: our first selection will skip 0. */
+	prev = __this_cpu_read(distribute_cpu_mask_prev);
+	next = find_next_bit_wrap(cpumask_bits(srcp), nr_cpumask_bits, prev + 1);
+	if (next < nr_cpu_ids)
+		__this_cpu_write(distribute_cpu_mask_prev, next);
+
+	return next;
+}
+EXPORT_SYMBOL(cpumask_any_distribute);