mirror of https://gitee.com/openkylin/linux.git
55 lines
1.4 KiB
C
55 lines
1.4 KiB
C
|
#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)
|
||
|
|
{
|
||
|
|
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) {
|
||
|
|
if (gfpflags_allow_blocking(gfp))
|
||
|
|
tlocks = kvmalloc(size * sizeof(spinlock_t), gfp);
|
||
|
|
else
|
||
|
|
tlocks = kmalloc_array(size, sizeof(spinlock_t), gfp);
|
||
|
|
if (!tlocks)
|
||
|
|
return -ENOMEM;
|
||
|
|
for (i = 0; i < size; i++)
|
||
|
|
spin_lock_init(&tlocks[i]);
|
||
|
|
}
|
||
|
|
|
||
|
|
*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);
|