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#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
/* Allocate an array of spinlocks to be accessed by a hash. Two arguments
* indicate the number of elements to allocate in the array. max_size
* gives the maximum number of elements to allocate. cpu_mult gives
* the number of locks per CPU to allocate. The size is rounded up
* to a power of 2 to be suitable as a hash table.
*/
int __alloc_bucket_spinlocks(spinlock_t **locks, unsigned int *locks_mask,
size_t max_size, unsigned int cpu_mult, gfp_t gfp,
const char *name, struct lock_class_key *key)
{
spinlock_t *tlocks = NULL;
unsigned int i, size;
#if defined(CONFIG_PROVE_LOCKING)
unsigned int nr_pcpus = 2;
#else
unsigned int nr_pcpus = num_possible_cpus();
#endif
if (cpu_mult) {
nr_pcpus = min_t(unsigned int, nr_pcpus, 64UL);
size = min_t(unsigned int, nr_pcpus * cpu_mult, max_size);
} else {
size = max_size;
}
if (sizeof(spinlock_t) != 0) {
tlocks = kvmalloc_array(size, sizeof(spinlock_t), gfp);
if (!tlocks)
return -ENOMEM;
for (i = 0; i < size; i++) {
spin_lock_init(&tlocks[i]);
lockdep_init_map(&tlocks[i].dep_map, name, key, 0);
}
}
*locks = tlocks;
*locks_mask = size - 1;
return 0;
}
EXPORT_SYMBOL(__alloc_bucket_spinlocks);
void free_bucket_spinlocks(spinlock_t *locks)
{
kvfree(locks);
}
EXPORT_SYMBOL(free_bucket_spinlocks);
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