diff options
Diffstat (limited to 'lib/cpumask.c')
-rw-r--r-- | lib/cpumask.c | 102 |
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); |