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Diffstat (limited to 'lib/cpumask.c')
-rw-r--r--lib/cpumask.c102
1 files changed, 26 insertions, 76 deletions
diff --git a/lib/cpumask.c b/lib/cpumask.c
index 5ab1553fd076..5f627084f2e9 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -5,27 +5,6 @@
#include <linux/export.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
-
/**
* cpumask_next_and - get the next cpu in *src1p & *src2p
* @n: the cpu prior to the place to search (ie. return will be > @n)
@@ -90,13 +69,6 @@ bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
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;
}
@@ -167,64 +139,42 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask)
#endif
/**
- * cpumask_set_cpu_local_first - set i'th cpu with local numa cpu's first
- *
+ * cpumask_local_spread - select the i'th cpu with local numa cpu's first
* @i: index number
- * @numa_node: local numa_node
- * @dstp: cpumask with the relevant cpu bit set according to the policy
+ * @node: local numa_node
*
- * This function sets the cpumask according to a numa aware policy.
- * cpumask could be used as an affinity hint for the IRQ related to a
- * queue. When the policy is to spread queues across cores - local cores
- * first.
+ * This function selects an online CPU according to a numa aware policy;
+ * local cpus are returned first, followed by non-local ones, then it
+ * wraps around.
*
- * Returns 0 on success, -ENOMEM for no memory, and -EAGAIN when failed to set
- * the cpu bit and need to re-call the function.
+ * It's not very efficient, but useful for setup.
*/
-int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp)
+unsigned int cpumask_local_spread(unsigned int i, int node)
{
- cpumask_var_t mask;
int cpu;
- int ret = 0;
-
- if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
- return -ENOMEM;
+ /* Wrap: we always want a cpu. */
i %= num_online_cpus();
- if (numa_node == -1 || !cpumask_of_node(numa_node)) {
- /* Use all online cpu's for non numa aware system */
- cpumask_copy(mask, cpu_online_mask);
+ if (node == -1) {
+ for_each_cpu(cpu, cpu_online_mask)
+ if (i-- == 0)
+ return cpu;
} else {
- int n;
-
- cpumask_and(mask,
- cpumask_of_node(numa_node), cpu_online_mask);
-
- n = cpumask_weight(mask);
- if (i >= n) {
- i -= n;
-
- /* If index > number of local cpu's, mask out local
- * cpu's
- */
- cpumask_andnot(mask, cpu_online_mask, mask);
+ /* NUMA first. */
+ for_each_cpu_and(cpu, cpumask_of_node(node), cpu_online_mask)
+ if (i-- == 0)
+ return cpu;
+
+ for_each_cpu(cpu, cpu_online_mask) {
+ /* Skip NUMA nodes, done above. */
+ if (cpumask_test_cpu(cpu, cpumask_of_node(node)))
+ continue;
+
+ if (i-- == 0)
+ return cpu;
}
}
-
- for_each_cpu(cpu, mask) {
- if (--i < 0)
- goto out;
- }
-
- ret = -EAGAIN;
-
-out:
- free_cpumask_var(mask);
-
- if (!ret)
- cpumask_set_cpu(cpu, dstp);
-
- return ret;
+ BUG();
}
-EXPORT_SYMBOL(cpumask_set_cpu_local_first);
+EXPORT_SYMBOL(cpumask_local_spread);