1 | #include <linux/export.h> |
2 | #include <linux/kernel.h> |
3 | #include <linux/mm.h> |
4 | #include <linux/slab.h> |
5 | #include <linux/vmalloc.h> |
6 | |
7 | /* Allocate an array of spinlocks to be accessed by a hash. Two arguments |
8 | * indicate the number of elements to allocate in the array. max_size |
9 | * gives the maximum number of elements to allocate. cpu_mult gives |
10 | * the number of locks per CPU to allocate. The size is rounded up |
11 | * to a power of 2 to be suitable as a hash table. |
12 | */ |
13 | |
14 | int __alloc_bucket_spinlocks(spinlock_t **locks, unsigned int *locks_mask, |
15 | size_t max_size, unsigned int cpu_mult, gfp_t gfp, |
16 | const char *name, struct lock_class_key *key) |
17 | { |
18 | spinlock_t *tlocks = NULL; |
19 | unsigned int i, size; |
20 | #if defined(CONFIG_PROVE_LOCKING) |
21 | unsigned int nr_pcpus = 2; |
22 | #else |
23 | unsigned int nr_pcpus = num_possible_cpus(); |
24 | #endif |
25 | |
26 | if (cpu_mult) { |
27 | nr_pcpus = min_t(unsigned int, nr_pcpus, 64UL); |
28 | size = min_t(unsigned int, nr_pcpus * cpu_mult, max_size); |
29 | } else { |
30 | size = max_size; |
31 | } |
32 | |
33 | if (sizeof(spinlock_t) != 0) { |
34 | tlocks = kvmalloc_array(n: size, size: sizeof(spinlock_t), flags: gfp); |
35 | if (!tlocks) |
36 | return -ENOMEM; |
37 | for (i = 0; i < size; i++) { |
38 | spin_lock_init(&tlocks[i]); |
39 | lockdep_init_map(lock: &tlocks[i].dep_map, name, key, subclass: 0); |
40 | } |
41 | } |
42 | |
43 | *locks = tlocks; |
44 | *locks_mask = size - 1; |
45 | |
46 | return 0; |
47 | } |
48 | EXPORT_SYMBOL(__alloc_bucket_spinlocks); |
49 | |
50 | void free_bucket_spinlocks(spinlock_t *locks) |
51 | { |
52 | kvfree(addr: locks); |
53 | } |
54 | EXPORT_SYMBOL(free_bucket_spinlocks); |
55 | |