LXR linux/kernel/lglock.c

   1/* See include/linux/lglock.h for description */
   2#include <linux/module.h>
   3#include <linux/lglock.h>
   4#include <linux/cpu.h>
   5#include <linux/string.h>
   6
   7/*
   8 * Note there is no uninit, so lglocks cannot be defined in
   9 * modules (but it's fine to use them from there)
  10 * Could be added though, just undo lg_lock_init
  11 */
  12
  13void lg_lock_init(struct lglock *lg, char *name)
  14{
  15        LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0);
  16}
  17EXPORT_SYMBOL(lg_lock_init);
  18
  19void lg_local_lock(struct lglock *lg)
  20{
  21        arch_spinlock_t *lock;
  22
  23        preempt_disable();
  24        rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
  25        lock = this_cpu_ptr(lg->lock);
  26        arch_spin_lock(lock);
  27}
  28EXPORT_SYMBOL(lg_local_lock);
  29
  30void lg_local_unlock(struct lglock *lg)
  31{
  32        arch_spinlock_t *lock;
  33
  34        rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
  35        lock = this_cpu_ptr(lg->lock);
  36        arch_spin_unlock(lock);
  37        preempt_enable();
  38}
  39EXPORT_SYMBOL(lg_local_unlock);
  40
  41void lg_local_lock_cpu(struct lglock *lg, int cpu)
  42{
  43        arch_spinlock_t *lock;
  44
  45        preempt_disable();
  46        rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
  47        lock = per_cpu_ptr(lg->lock, cpu);
  48        arch_spin_lock(lock);
  49}
  50EXPORT_SYMBOL(lg_local_lock_cpu);
  51
  52void lg_local_unlock_cpu(struct lglock *lg, int cpu)
  53{
  54        arch_spinlock_t *lock;
  55
  56        rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
  57        lock = per_cpu_ptr(lg->lock, cpu);
  58        arch_spin_unlock(lock);
  59        preempt_enable();
  60}
  61EXPORT_SYMBOL(lg_local_unlock_cpu);
  62
  63void lg_global_lock(struct lglock *lg)
  64{
  65        int i;
  66
  67        preempt_disable();
  68        rwlock_acquire(&lg->lock_dep_map, 0, 0, _RET_IP_);
  69        for_each_possible_cpu(i) {
  70                arch_spinlock_t *lock;
  71                lock = per_cpu_ptr(lg->lock, i);
  72                arch_spin_lock(lock);
  73        }
  74}
  75EXPORT_SYMBOL(lg_global_lock);
  76
  77void lg_global_unlock(struct lglock *lg)
  78{
  79        int i;
  80
  81        rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
  82        for_each_possible_cpu(i) {
  83                arch_spinlock_t *lock;
  84                lock = per_cpu_ptr(lg->lock, i);
  85                arch_spin_unlock(lock);
  86        }
  87        preempt_enable();
  88}
  89EXPORT_SYMBOL(lg_global_unlock);
  90