+fastcall void put_pid(struct pid *pid)
+{
+ if (!pid)
+ return;
+ if ((atomic_read(&pid->count) == 1) ||
+ atomic_dec_and_test(&pid->count))
+ kmem_cache_free(pid_cachep, pid);
+}
+EXPORT_SYMBOL_GPL(put_pid);
+
+static void delayed_put_pid(struct rcu_head *rhp)
+{
+ struct pid *pid = container_of(rhp, struct pid, rcu);
+ put_pid(pid);
+}
+
+fastcall void free_pid(struct pid *pid)
+{
+ /* We can be called with write_lock_irq(&tasklist_lock) held */
+ unsigned long flags;
+
+ spin_lock_irqsave(&pidmap_lock, flags);
+ hlist_del_rcu(&pid->pid_chain);
+ spin_unlock_irqrestore(&pidmap_lock, flags);
+
+ free_pidmap(&init_pid_ns, pid->nr);
+ call_rcu(&pid->rcu, delayed_put_pid);
+}
+
+struct pid *alloc_pid(void)
+{
+ struct pid *pid;
+ enum pid_type type;
+ int nr = -1;
+
+ pid = kmem_cache_alloc(pid_cachep, GFP_KERNEL);
+ if (!pid)
+ goto out;
+
+ nr = alloc_pidmap(current->nsproxy->pid_ns);
+ if (nr < 0)
+ goto out_free;
+
+ atomic_set(&pid->count, 1);
+ pid->nr = nr;
+ for (type = 0; type < PIDTYPE_MAX; ++type)
+ INIT_HLIST_HEAD(&pid->tasks[type]);
+
+ spin_lock_irq(&pidmap_lock);
+ hlist_add_head_rcu(&pid->pid_chain, &pid_hash[pid_hashfn(pid->nr)]);
+ spin_unlock_irq(&pidmap_lock);
+
+out:
+ return pid;
+
+out_free:
+ kmem_cache_free(pid_cachep, pid);
+ pid = NULL;
+ goto out;
+}
+
+struct pid * fastcall find_pid(int nr)