#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);