blob: 05d6aca7fc1905defed315f2f14df86d231741b6 [file] [log] [blame]
Tejun Heo5a0e3ad2010-03-24 17:04:11 +09001#include <linux/slab.h>
Andrew Mortonccb46002006-03-25 03:08:08 -08002#include <linux/kernel.h>
3#include <linux/bitops.h>
4#include <linux/cpumask.h>
5#include <linux/module.h>
Rusty Russell2d3854a2008-11-05 13:39:10 +11006#include <linux/bootmem.h>
Andrew Mortonccb46002006-03-25 03:08:08 -08007
8int __first_cpu(const cpumask_t *srcp)
9{
10 return min_t(int, NR_CPUS, find_first_bit(srcp->bits, NR_CPUS));
11}
12EXPORT_SYMBOL(__first_cpu);
13
Andrew Morton3d18bd72006-03-25 03:08:09 -080014int __next_cpu(int n, const cpumask_t *srcp)
15{
16 return min_t(int, NR_CPUS, find_next_bit(srcp->bits, NR_CPUS, n+1));
17}
18EXPORT_SYMBOL(__next_cpu);
Andrew Morton86302822006-03-25 03:08:09 -080019
Mike Travis41df0d612008-05-12 21:21:13 +020020#if NR_CPUS > 64
21int __next_cpu_nr(int n, const cpumask_t *srcp)
22{
23 return min_t(int, nr_cpu_ids,
24 find_next_bit(srcp->bits, nr_cpu_ids, n+1));
25}
26EXPORT_SYMBOL(__next_cpu_nr);
27#endif
28
Andrew Morton96a9b4d2006-03-25 03:08:10 -080029int __any_online_cpu(const cpumask_t *mask)
30{
31 int cpu;
32
33 for_each_cpu_mask(cpu, *mask) {
34 if (cpu_online(cpu))
35 break;
36 }
37 return cpu;
38}
39EXPORT_SYMBOL(__any_online_cpu);
Rusty Russell2d3854a2008-11-05 13:39:10 +110040
41/**
42 * cpumask_next_and - get the next cpu in *src1p & *src2p
43 * @n: the cpu prior to the place to search (ie. return will be > @n)
44 * @src1p: the first cpumask pointer
45 * @src2p: the second cpumask pointer
46 *
47 * Returns >= nr_cpu_ids if no further cpus set in both.
48 */
49int cpumask_next_and(int n, const struct cpumask *src1p,
50 const struct cpumask *src2p)
51{
52 while ((n = cpumask_next(n, src1p)) < nr_cpu_ids)
53 if (cpumask_test_cpu(n, src2p))
54 break;
55 return n;
56}
57EXPORT_SYMBOL(cpumask_next_and);
58
59/**
60 * cpumask_any_but - return a "random" in a cpumask, but not this one.
61 * @mask: the cpumask to search
62 * @cpu: the cpu to ignore.
63 *
64 * Often used to find any cpu but smp_processor_id() in a mask.
65 * Returns >= nr_cpu_ids if no cpus set.
66 */
67int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
68{
69 unsigned int i;
70
Rusty Russell984f2f32008-11-08 20:24:19 +110071 cpumask_check(cpu);
Rusty Russell2d3854a2008-11-05 13:39:10 +110072 for_each_cpu(i, mask)
73 if (i != cpu)
74 break;
75 return i;
76}
77
78/* These are not inline because of header tangles. */
79#ifdef CONFIG_CPUMASK_OFFSTACK
Mike Travisec26b802008-12-19 16:56:52 +103080/**
81 * alloc_cpumask_var_node - allocate a struct cpumask on a given node
82 * @mask: pointer to cpumask_var_t where the cpumask is returned
83 * @flags: GFP_ flags
84 *
85 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
86 * a nop returning a constant 1 (in <linux/cpumask.h>)
87 * Returns TRUE if memory allocation succeeded, FALSE otherwise.
88 *
89 * In addition, mask will be NULL if this fails. Note that gcc is
90 * usually smart enough to know that mask can never be NULL if
91 * CONFIG_CPUMASK_OFFSTACK=n, so does code elimination in that case
92 * too.
93 */
Mike Travis7b4967c2008-12-19 16:56:37 +103094bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
Rusty Russell2d3854a2008-11-05 13:39:10 +110095{
Yinghai Lu38c7fed2009-05-25 15:10:58 +030096 *mask = kmalloc_node(cpumask_size(), flags, node);
97
Rusty Russell2d3854a2008-11-05 13:39:10 +110098#ifdef CONFIG_DEBUG_PER_CPU_MAPS
99 if (!*mask) {
100 printk(KERN_ERR "=> alloc_cpumask_var: failed!\n");
101 dump_stack();
102 }
103#endif
Rusty Russell2a530082009-01-01 10:12:30 +1030104 /* FIXME: Bandaid to save us from old primitives which go to NR_CPUS. */
105 if (*mask) {
Jack Steiner4f032ac2009-04-02 16:59:48 -0700106 unsigned char *ptr = (unsigned char *)cpumask_bits(*mask);
Rusty Russell2a530082009-01-01 10:12:30 +1030107 unsigned int tail;
108 tail = BITS_TO_LONGS(NR_CPUS - nr_cpumask_bits) * sizeof(long);
Jack Steiner4f032ac2009-04-02 16:59:48 -0700109 memset(ptr + cpumask_size() - tail, 0, tail);
Rusty Russell2a530082009-01-01 10:12:30 +1030110 }
111
Rusty Russell2d3854a2008-11-05 13:39:10 +1100112 return *mask != NULL;
113}
Mike Travis7b4967c2008-12-19 16:56:37 +1030114EXPORT_SYMBOL(alloc_cpumask_var_node);
115
Yinghai Lu0281b5d2009-06-06 14:50:36 -0700116bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
117{
118 return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
119}
120EXPORT_SYMBOL(zalloc_cpumask_var_node);
121
Mike Travisec26b802008-12-19 16:56:52 +1030122/**
123 * alloc_cpumask_var - allocate a struct cpumask
124 * @mask: pointer to cpumask_var_t where the cpumask is returned
125 * @flags: GFP_ flags
126 *
127 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
128 * a nop returning a constant 1 (in <linux/cpumask.h>).
129 *
130 * See alloc_cpumask_var_node.
131 */
Mike Travis7b4967c2008-12-19 16:56:37 +1030132bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
133{
134 return alloc_cpumask_var_node(mask, flags, numa_node_id());
135}
Rusty Russell2d3854a2008-11-05 13:39:10 +1100136EXPORT_SYMBOL(alloc_cpumask_var);
137
Yinghai Lu0281b5d2009-06-06 14:50:36 -0700138bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
139{
140 return alloc_cpumask_var(mask, flags | __GFP_ZERO);
141}
142EXPORT_SYMBOL(zalloc_cpumask_var);
143
Mike Travisec26b802008-12-19 16:56:52 +1030144/**
145 * alloc_bootmem_cpumask_var - allocate a struct cpumask from the bootmem arena.
146 * @mask: pointer to cpumask_var_t where the cpumask is returned
147 *
148 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
Li Zefane9690a62008-12-31 16:45:50 +0800149 * a nop (in <linux/cpumask.h>).
Mike Travisec26b802008-12-19 16:56:52 +1030150 * Either returns an allocated (zero-filled) cpumask, or causes the
151 * system to panic.
152 */
Rusty Russell2d3854a2008-11-05 13:39:10 +1100153void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask)
154{
155 *mask = alloc_bootmem(cpumask_size());
156}
157
Mike Travisec26b802008-12-19 16:56:52 +1030158/**
159 * free_cpumask_var - frees memory allocated for a struct cpumask.
160 * @mask: cpumask to free
161 *
162 * This is safe on a NULL mask.
163 */
Rusty Russell2d3854a2008-11-05 13:39:10 +1100164void free_cpumask_var(cpumask_var_t mask)
165{
166 kfree(mask);
167}
168EXPORT_SYMBOL(free_cpumask_var);
Rusty Russellcd83e422008-11-07 11:12:29 +1100169
Mike Travisec26b802008-12-19 16:56:52 +1030170/**
171 * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var
172 * @mask: cpumask to free
173 */
Rusty Russell984f2f32008-11-08 20:24:19 +1100174void __init free_bootmem_cpumask_var(cpumask_var_t mask)
Rusty Russellcd83e422008-11-07 11:12:29 +1100175{
176 free_bootmem((unsigned long)mask, cpumask_size());
177}
Rusty Russell2d3854a2008-11-05 13:39:10 +1100178#endif