/* See include/linux/lglock.h for description */ #include <linux/module.h> #include <linux/lglock.h> #include <linux/cpu.h> #include <linux/string.h> /* * Note there is no uninit, so lglocks cannot be defined in * modules (but it's fine to use them from there) * Could be added though, just undo lg_lock_init */ void lg_lock_init(struct lglock *lg, char *name) { LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0); } EXPORT_SYMBOL(lg_lock_init); void lg_local_lock(struct lglock *lg) { arch_spinlock_t *lock; preempt_disable(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); lock = this_cpu_ptr(lg->lock); arch_spin_lock(lock); } EXPORT_SYMBOL(lg_local_lock); void lg_local_unlock(struct lglock *lg) { arch_spinlock_t *lock; lock_release(&lg->lock_dep_map, 1, _RET_IP_); lock = this_cpu_ptr(lg->lock); arch_spin_unlock(lock); preempt_enable(); } EXPORT_SYMBOL(lg_local_unlock); void lg_local_lock_cpu(struct lglock *lg, int cpu) { arch_spinlock_t *lock; preempt_disable(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); lock = per_cpu_ptr(lg->lock, cpu); arch_spin_lock(lock); } EXPORT_SYMBOL(lg_local_lock_cpu); void lg_local_unlock_cpu(struct lglock *lg, int cpu) { arch_spinlock_t *lock; lock_release(&lg->lock_dep_map, 1, _RET_IP_); lock = per_cpu_ptr(lg->lock, cpu); arch_spin_unlock(lock); preempt_enable(); } EXPORT_SYMBOL(lg_local_unlock_cpu); void lg_double_lock(struct lglock *lg, int cpu1, int cpu2) { BUG_ON(cpu1 == cpu2); /* lock in cpu order, just like lg_global_lock */ if (cpu2 < cpu1) swap(cpu1, cpu2); preempt_disable(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); arch_spin_lock(per_cpu_ptr(lg->lock, cpu1)); arch_spin_lock(per_cpu_ptr(lg->lock, cpu2)); } void lg_double_unlock(struct lglock *lg, int cpu1, int cpu2) { lock_release(&lg->lock_dep_map, 1, _RET_IP_); arch_spin_unlock(per_cpu_ptr(lg->lock, cpu1)); arch_spin_unlock(per_cpu_ptr(lg->lock, cpu2)); preempt_enable(); } void lg_global_lock(struct lglock *lg) { int i; preempt_disable(); lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); for_each_possible_cpu(i) { arch_spinlock_t *lock; lock = per_cpu_ptr(lg->lock, i); arch_spin_lock(lock); } } EXPORT_SYMBOL(lg_global_lock); void lg_global_unlock(struct lglock *lg) { int i; lock_release(&lg->lock_dep_map, 1, _RET_IP_); for_each_possible_cpu(i) { arch_spinlock_t *lock; lock = per_cpu_ptr(lg->lock, i); arch_spin_unlock(lock); } preempt_enable(); } EXPORT_SYMBOL(lg_global_unlock);