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>
  7
  8/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  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
 13 *
 14 * Returns >= nr_cpu_ids if no further cpus set in both.
 15 */
 16int cpumask_next_and(int n, const struct cpumask *src1p,
 17		     const struct cpumask *src2p)
 18{
 19	while ((n = cpumask_next(n, src1p)) < nr_cpu_ids)
 20		if (cpumask_test_cpu(n, src2p))
 21			break;
 22	return n;
 
 23}
 24EXPORT_SYMBOL(cpumask_next_and);
 25
 26/**
 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.
 30 *
 31 * Often used to find any cpu but smp_processor_id() in a mask.
 32 * Returns >= nr_cpu_ids if no cpus set.
 33 */
 34int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
 35{
 36	unsigned int i;
 37
 38	cpumask_check(cpu);
 39	for_each_cpu(i, mask)
 40		if (i != cpu)
 41			break;
 42	return i;
 43}
 44EXPORT_SYMBOL(cpumask_any_but);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 45
 46/* These are not inline because of header tangles. */
 47#ifdef CONFIG_CPUMASK_OFFSTACK
 48/**
 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
 51 * @flags: GFP_ flags
 52 *
 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.
 56 *
 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
 60 * too.
 61 */
 62bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
 63{
 64	*mask = kmalloc_node(cpumask_size(), flags, node);
 65
 66#ifdef CONFIG_DEBUG_PER_CPU_MAPS
 67	if (!*mask) {
 68		printk(KERN_ERR "=> alloc_cpumask_var: failed!\n");
 69		dump_stack();
 70	}
 71#endif
 72
 73	return *mask != NULL;
 74}
 75EXPORT_SYMBOL(alloc_cpumask_var_node);
 76
 77bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
 78{
 79	return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
 80}
 81EXPORT_SYMBOL(zalloc_cpumask_var_node);
 82
 83/**
 84 * alloc_cpumask_var - allocate a struct cpumask
 85 * @mask: pointer to cpumask_var_t where the cpumask is returned
 86 * @flags: GFP_ flags
 87 *
 88 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
 89 * a nop returning a constant 1 (in <linux/cpumask.h>).
 90 *
 91 * See alloc_cpumask_var_node.
 92 */
 93bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
 94{
 95	return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
 96}
 97EXPORT_SYMBOL(alloc_cpumask_var);
 98
 99bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
100{
101	return alloc_cpumask_var(mask, flags | __GFP_ZERO);
102}
103EXPORT_SYMBOL(zalloc_cpumask_var);
104
105/**
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
108 *
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
112 * system to panic.
113 */
114void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask)
115{
116	*mask = memblock_virt_alloc(cpumask_size(), 0);
117}
118
119/**
120 * free_cpumask_var - frees memory allocated for a struct cpumask.
121 * @mask: cpumask to free
122 *
123 * This is safe on a NULL mask.
124 */
125void free_cpumask_var(cpumask_var_t mask)
126{
127	kfree(mask);
128}
129EXPORT_SYMBOL(free_cpumask_var);
130
131/**
132 * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var
133 * @mask: cpumask to free
134 */
135void __init free_bootmem_cpumask_var(cpumask_var_t mask)
136{
137	memblock_free_early(__pa(mask), cpumask_size());
138}
139#endif
140
141/**
142 * cpumask_local_spread - select the i'th cpu with local numa cpu's first
143 * @i: index number
144 * @node: local numa_node
145 *
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
148 * wraps around.
149 *
150 * It's not very efficient, but useful for setup.
151 */
152unsigned int cpumask_local_spread(unsigned int i, int node)
153{
154	int cpu;
155
156	/* Wrap: we always want a cpu. */
157	i %= num_online_cpus();
158
159	if (node == -1) {
160		for_each_cpu(cpu, cpu_online_mask)
161			if (i-- == 0)
162				return cpu;
163	} else {
164		/* NUMA first. */
165		for_each_cpu_and(cpu, cpumask_of_node(node), cpu_online_mask)
166			if (i-- == 0)
167				return cpu;
168
169		for_each_cpu(cpu, cpu_online_mask) {
170			/* Skip NUMA nodes, done above. */
171			if (cpumask_test_cpu(cpu, cpumask_of_node(node)))
172				continue;
173
174			if (i-- == 0)
175				return cpu;
176		}
177	}
178	BUG();
179}
180EXPORT_SYMBOL(cpumask_local_spread);

  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/slab.h>
  3#include <linux/kernel.h>
  4#include <linux/bitops.h>
  5#include <linux/cpumask.h>
  6#include <linux/export.h>
  7#include <linux/bootmem.h>
  8
  9/**
 10 * cpumask_next - get the next cpu in a cpumask
 11 * @n: the cpu prior to the place to search (ie. return will be > @n)
 12 * @srcp: the cpumask pointer
 13 *
 14 * Returns >= nr_cpu_ids if no further cpus set.
 15 */
 16unsigned int cpumask_next(int n, const struct cpumask *srcp)
 17{
 18	/* -1 is a legal arg here. */
 19	if (n != -1)
 20		cpumask_check(n);
 21	return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1);
 22}
 23EXPORT_SYMBOL(cpumask_next);
 24
 25/**
 26 * cpumask_next_and - get the next cpu in *src1p & *src2p
 27 * @n: the cpu prior to the place to search (ie. return will be > @n)
 28 * @src1p: the first cpumask pointer
 29 * @src2p: the second cpumask pointer
 30 *
 31 * Returns >= nr_cpu_ids if no further cpus set in both.
 32 */
 33int cpumask_next_and(int n, const struct cpumask *src1p,
 34		     const struct cpumask *src2p)
 35{
 36	/* -1 is a legal arg here. */
 37	if (n != -1)
 38		cpumask_check(n);
 39	return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
 40		nr_cpumask_bits, n + 1);
 41}
 42EXPORT_SYMBOL(cpumask_next_and);
 43
 44/**
 45 * cpumask_any_but - return a "random" in a cpumask, but not this one.
 46 * @mask: the cpumask to search
 47 * @cpu: the cpu to ignore.
 48 *
 49 * Often used to find any cpu but smp_processor_id() in a mask.
 50 * Returns >= nr_cpu_ids if no cpus set.
 51 */
 52int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
 53{
 54	unsigned int i;
 55
 56	cpumask_check(cpu);
 57	for_each_cpu(i, mask)
 58		if (i != cpu)
 59			break;
 60	return i;
 61}
 62EXPORT_SYMBOL(cpumask_any_but);
 63
 64/**
 65 * cpumask_next_wrap - helper to implement for_each_cpu_wrap
 66 * @n: the cpu prior to the place to search
 67 * @mask: the cpumask pointer
 68 * @start: the start point of the iteration
 69 * @wrap: assume @n crossing @start terminates the iteration
 70 *
 71 * Returns >= nr_cpu_ids on completion
 72 *
 73 * Note: the @wrap argument is required for the start condition when
 74 * we cannot assume @start is set in @mask.
 75 */
 76int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
 77{
 78	int next;
 79
 80again:
 81	next = cpumask_next(n, mask);
 82
 83	if (wrap && n < start && next >= start) {
 84		return nr_cpumask_bits;
 85
 86	} else if (next >= nr_cpumask_bits) {
 87		wrap = true;
 88		n = -1;
 89		goto again;
 90	}
 91
 92	return next;
 93}
 94EXPORT_SYMBOL(cpumask_next_wrap);
 95
 96/* These are not inline because of header tangles. */
 97#ifdef CONFIG_CPUMASK_OFFSTACK
 98/**
 99 * alloc_cpumask_var_node - allocate a struct cpumask on a given node
100 * @mask: pointer to cpumask_var_t where the cpumask is returned
101 * @flags: GFP_ flags
102 *
103 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
104 * a nop returning a constant 1 (in <linux/cpumask.h>)
105 * Returns TRUE if memory allocation succeeded, FALSE otherwise.
106 *
107 * In addition, mask will be NULL if this fails.  Note that gcc is
108 * usually smart enough to know that mask can never be NULL if
109 * CONFIG_CPUMASK_OFFSTACK=n, so does code elimination in that case
110 * too.
111 */
112bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
113{
114	*mask = kmalloc_node(cpumask_size(), flags, node);
115
116#ifdef CONFIG_DEBUG_PER_CPU_MAPS
117	if (!*mask) {
118		printk(KERN_ERR "=> alloc_cpumask_var: failed!\n");
119		dump_stack();
120	}
121#endif
122
123	return *mask != NULL;
124}
125EXPORT_SYMBOL(alloc_cpumask_var_node);
126
127bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
128{
129	return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
130}
131EXPORT_SYMBOL(zalloc_cpumask_var_node);
132
133/**
134 * alloc_cpumask_var - allocate a struct cpumask
135 * @mask: pointer to cpumask_var_t where the cpumask is returned
136 * @flags: GFP_ flags
137 *
138 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
139 * a nop returning a constant 1 (in <linux/cpumask.h>).
140 *
141 * See alloc_cpumask_var_node.
142 */
143bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
144{
145	return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
146}
147EXPORT_SYMBOL(alloc_cpumask_var);
148
149bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
150{
151	return alloc_cpumask_var(mask, flags | __GFP_ZERO);
152}
153EXPORT_SYMBOL(zalloc_cpumask_var);
154
155/**
156 * alloc_bootmem_cpumask_var - allocate a struct cpumask from the bootmem arena.
157 * @mask: pointer to cpumask_var_t where the cpumask is returned
158 *
159 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
160 * a nop (in <linux/cpumask.h>).
161 * Either returns an allocated (zero-filled) cpumask, or causes the
162 * system to panic.
163 */
164void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask)
165{
166	*mask = memblock_virt_alloc(cpumask_size(), 0);
167}
168
169/**
170 * free_cpumask_var - frees memory allocated for a struct cpumask.
171 * @mask: cpumask to free
172 *
173 * This is safe on a NULL mask.
174 */
175void free_cpumask_var(cpumask_var_t mask)
176{
177	kfree(mask);
178}
179EXPORT_SYMBOL(free_cpumask_var);
180
181/**
182 * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var
183 * @mask: cpumask to free
184 */
185void __init free_bootmem_cpumask_var(cpumask_var_t mask)
186{
187	memblock_free_early(__pa(mask), cpumask_size());
188}
189#endif
190
191/**
192 * cpumask_local_spread - select the i'th cpu with local numa cpu's first
193 * @i: index number
194 * @node: local numa_node
195 *
196 * This function selects an online CPU according to a numa aware policy;
197 * local cpus are returned first, followed by non-local ones, then it
198 * wraps around.
199 *
200 * It's not very efficient, but useful for setup.
201 */
202unsigned int cpumask_local_spread(unsigned int i, int node)
203{
204	int cpu;
205
206	/* Wrap: we always want a cpu. */
207	i %= num_online_cpus();
208
209	if (node == -1) {
210		for_each_cpu(cpu, cpu_online_mask)
211			if (i-- == 0)
212				return cpu;
213	} else {
214		/* NUMA first. */
215		for_each_cpu_and(cpu, cpumask_of_node(node), cpu_online_mask)
216			if (i-- == 0)
217				return cpu;
218
219		for_each_cpu(cpu, cpu_online_mask) {
220			/* Skip NUMA nodes, done above. */
221			if (cpumask_test_cpu(cpu, cpumask_of_node(node)))
222				continue;
223
224			if (i-- == 0)
225				return cpu;
226		}
227	}
228	BUG();
229}
230EXPORT_SYMBOL(cpumask_local_spread);