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-rw-r--r--lib/cpumask.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/lib/cpumask.c b/lib/cpumask.c
new file mode 100644
index 00000000..05d6aca7
--- /dev/null
+++ b/lib/cpumask.c
@@ -0,0 +1,178 @@
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/cpumask.h>
+#include <linux/module.h>
+#include <linux/bootmem.h>
+
+int __first_cpu(const cpumask_t *srcp)
+{
+ return min_t(int, NR_CPUS, find_first_bit(srcp->bits, NR_CPUS));
+}
+EXPORT_SYMBOL(__first_cpu);
+
+int __next_cpu(int n, const cpumask_t *srcp)
+{
+ return min_t(int, NR_CPUS, find_next_bit(srcp->bits, NR_CPUS, n+1));
+}
+EXPORT_SYMBOL(__next_cpu);
+
+#if NR_CPUS > 64
+int __next_cpu_nr(int n, const cpumask_t *srcp)
+{
+ return min_t(int, nr_cpu_ids,
+ find_next_bit(srcp->bits, nr_cpu_ids, n+1));
+}
+EXPORT_SYMBOL(__next_cpu_nr);
+#endif
+
+int __any_online_cpu(const cpumask_t *mask)
+{
+ int cpu;
+
+ for_each_cpu_mask(cpu, *mask) {
+ if (cpu_online(cpu))
+ break;
+ }
+ return cpu;
+}
+EXPORT_SYMBOL(__any_online_cpu);
+
+/**
+ * cpumask_next_and - 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 >= nr_cpu_ids if no further cpus set in both.
+ */
+int cpumask_next_and(int n, const struct cpumask *src1p,
+ const struct cpumask *src2p)
+{
+ while ((n = cpumask_next(n, src1p)) < nr_cpu_ids)
+ if (cpumask_test_cpu(n, src2p))
+ break;
+ return n;
+}
+EXPORT_SYMBOL(cpumask_next_and);
+
+/**
+ * cpumask_any_but - return a "random" in a cpumask, but not this one.
+ * @mask: the cpumask to search
+ * @cpu: the cpu to ignore.
+ *
+ * Often used to find any cpu but smp_processor_id() in a mask.
+ * Returns >= nr_cpu_ids if no cpus set.
+ */
+int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
+{
+ unsigned int i;
+
+ cpumask_check(cpu);
+ for_each_cpu(i, mask)
+ if (i != cpu)
+ break;
+ return i;
+}
+
+/* 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
+ *
+ * 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
+ /* FIXME: Bandaid to save us from old primitives which go to NR_CPUS. */
+ if (*mask) {
+ unsigned char *ptr = (unsigned char *)cpumask_bits(*mask);
+ unsigned int tail;
+ tail = BITS_TO_LONGS(NR_CPUS - nr_cpumask_bits) * sizeof(long);
+ memset(ptr + cpumask_size() - tail, 0, tail);
+ }
+
+ return *mask != NULL;
+}
+EXPORT_SYMBOL(alloc_cpumask_var_node);
+
+bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
+{
+ return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
+}
+EXPORT_SYMBOL(zalloc_cpumask_var_node);
+
+/**
+ * alloc_cpumask_var - allocate a struct cpumask
+ * @mask: pointer to cpumask_var_t where the cpumask is returned
+ * @flags: GFP_ flags
+ *
+ * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
+ * a nop returning a constant 1 (in <linux/cpumask.h>).
+ *
+ * See alloc_cpumask_var_node.
+ */
+bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+ return alloc_cpumask_var_node(mask, flags, numa_node_id());
+}
+EXPORT_SYMBOL(alloc_cpumask_var);
+
+bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+ return alloc_cpumask_var(mask, flags | __GFP_ZERO);
+}
+EXPORT_SYMBOL(zalloc_cpumask_var);
+
+/**
+ * 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 = alloc_bootmem(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)
+{
+ free_bootmem((unsigned long)mask, cpumask_size());
+}
+#endif