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git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - lib/cpumask.c
1 #include <linux/slab.h>
2 #include <linux/kernel.h>
3 #include <linux/bitops.h>
4 #include <linux/cpumask.h>
5 #include <linux/export.h>
6 #include <linux/bootmem.h>
9 * cpumask_next_and - get the next cpu in *src1p & *src2p
10 * @n: the cpu prior to the place to search (ie. return will be > @n)
11 * @src1p: the first cpumask pointer
12 * @src2p: the second cpumask pointer
14 * Returns >= nr_cpu_ids if no further cpus set in both.
16 int cpumask_next_and(int n
, const struct cpumask
*src1p
,
17 const struct cpumask
*src2p
)
19 while ((n
= cpumask_next(n
, src1p
)) < nr_cpu_ids
)
20 if (cpumask_test_cpu(n
, src2p
))
24 EXPORT_SYMBOL(cpumask_next_and
);
27 * cpumask_any_but - return a "random" in a cpumask, but not this one.
28 * @mask: the cpumask to search
29 * @cpu: the cpu to ignore.
31 * Often used to find any cpu but smp_processor_id() in a mask.
32 * Returns >= nr_cpu_ids if no cpus set.
34 int cpumask_any_but(const struct cpumask
*mask
, unsigned int cpu
)
44 EXPORT_SYMBOL(cpumask_any_but
);
46 /* These are not inline because of header tangles. */
47 #ifdef CONFIG_CPUMASK_OFFSTACK
49 * alloc_cpumask_var_node - allocate a struct cpumask on a given node
50 * @mask: pointer to cpumask_var_t where the cpumask is returned
53 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
54 * a nop returning a constant 1 (in <linux/cpumask.h>)
55 * Returns TRUE if memory allocation succeeded, FALSE otherwise.
57 * In addition, mask will be NULL if this fails. Note that gcc is
58 * usually smart enough to know that mask can never be NULL if
59 * CONFIG_CPUMASK_OFFSTACK=n, so does code elimination in that case
62 bool alloc_cpumask_var_node(cpumask_var_t
*mask
, gfp_t flags
, int node
)
64 *mask
= kmalloc_node(cpumask_size(), flags
, node
);
66 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
68 printk(KERN_ERR
"=> alloc_cpumask_var: failed!\n");
75 EXPORT_SYMBOL(alloc_cpumask_var_node
);
77 bool zalloc_cpumask_var_node(cpumask_var_t
*mask
, gfp_t flags
, int node
)
79 return alloc_cpumask_var_node(mask
, flags
| __GFP_ZERO
, node
);
81 EXPORT_SYMBOL(zalloc_cpumask_var_node
);
84 * alloc_cpumask_var - allocate a struct cpumask
85 * @mask: pointer to cpumask_var_t where the cpumask is returned
88 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
89 * a nop returning a constant 1 (in <linux/cpumask.h>).
91 * See alloc_cpumask_var_node.
93 bool alloc_cpumask_var(cpumask_var_t
*mask
, gfp_t flags
)
95 return alloc_cpumask_var_node(mask
, flags
, NUMA_NO_NODE
);
97 EXPORT_SYMBOL(alloc_cpumask_var
);
99 bool zalloc_cpumask_var(cpumask_var_t
*mask
, gfp_t flags
)
101 return alloc_cpumask_var(mask
, flags
| __GFP_ZERO
);
103 EXPORT_SYMBOL(zalloc_cpumask_var
);
106 * alloc_bootmem_cpumask_var - allocate a struct cpumask from the bootmem arena.
107 * @mask: pointer to cpumask_var_t where the cpumask is returned
109 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
110 * a nop (in <linux/cpumask.h>).
111 * Either returns an allocated (zero-filled) cpumask, or causes the
114 void __init
alloc_bootmem_cpumask_var(cpumask_var_t
*mask
)
116 *mask
= memblock_virt_alloc(cpumask_size(), 0);
120 * free_cpumask_var - frees memory allocated for a struct cpumask.
121 * @mask: cpumask to free
123 * This is safe on a NULL mask.
125 void free_cpumask_var(cpumask_var_t mask
)
129 EXPORT_SYMBOL(free_cpumask_var
);
132 * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var
133 * @mask: cpumask to free
135 void __init
free_bootmem_cpumask_var(cpumask_var_t mask
)
137 memblock_free_early(__pa(mask
), cpumask_size());
142 * cpumask_local_spread - select the i'th cpu with local numa cpu's first
144 * @node: local numa_node
146 * This function selects an online CPU according to a numa aware policy;
147 * local cpus are returned first, followed by non-local ones, then it
150 * It's not very efficient, but useful for setup.
152 unsigned int cpumask_local_spread(unsigned int i
, int node
)
156 /* Wrap: we always want a cpu. */
157 i
%= num_online_cpus();
160 for_each_cpu(cpu
, cpu_online_mask
)
165 for_each_cpu_and(cpu
, cpumask_of_node(node
), cpu_online_mask
)
169 for_each_cpu(cpu
, cpu_online_mask
) {
170 /* Skip NUMA nodes, done above. */
171 if (cpumask_test_cpu(cpu
, cpumask_of_node(node
)))
180 EXPORT_SYMBOL(cpumask_local_spread
);