6b13f685e
김민수
BSP 최초 추가
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#include "core.h"
struct queue_item {
struct list_head next_signal;
void (*handler) (unsigned long);
unsigned long data;
};
static struct kmem_cache *tipc_queue_item_cache;
static struct list_head signal_queue_head;
static DEFINE_SPINLOCK(qitem_lock);
static int handler_enabled __read_mostly;
static void process_signal_queue(unsigned long dummy);
static DECLARE_TASKLET_DISABLED(tipc_tasklet, process_signal_queue, 0);
unsigned int tipc_k_signal(Handler routine, unsigned long argument)
{
struct queue_item *item;
spin_lock_bh(&qitem_lock);
if (!handler_enabled) {
spin_unlock_bh(&qitem_lock);
return -ENOPROTOOPT;
}
item = kmem_cache_alloc(tipc_queue_item_cache, GFP_ATOMIC);
if (!item) {
pr_err("Signal queue out of memory
");
spin_unlock_bh(&qitem_lock);
return -ENOMEM;
}
item->handler = routine;
item->data = argument;
list_add_tail(&item->next_signal, &signal_queue_head);
spin_unlock_bh(&qitem_lock);
tasklet_schedule(&tipc_tasklet);
return 0;
}
static void process_signal_queue(unsigned long dummy)
{
struct queue_item *__volatile__ item;
struct list_head *l, *n;
spin_lock_bh(&qitem_lock);
list_for_each_safe(l, n, &signal_queue_head) {
item = list_entry(l, struct queue_item, next_signal);
list_del(&item->next_signal);
spin_unlock_bh(&qitem_lock);
item->handler(item->data);
spin_lock_bh(&qitem_lock);
kmem_cache_free(tipc_queue_item_cache, item);
}
spin_unlock_bh(&qitem_lock);
}
int tipc_handler_start(void)
{
tipc_queue_item_cache =
kmem_cache_create("tipc_queue_items", sizeof(struct queue_item),
0, SLAB_HWCACHE_ALIGN, NULL);
if (!tipc_queue_item_cache)
return -ENOMEM;
INIT_LIST_HEAD(&signal_queue_head);
tasklet_enable(&tipc_tasklet);
handler_enabled = 1;
return 0;
}
void tipc_handler_stop(void)
{
struct list_head *l, *n;
struct queue_item *item;
spin_lock_bh(&qitem_lock);
if (!handler_enabled) {
spin_unlock_bh(&qitem_lock);
return;
}
handler_enabled = 0;
spin_unlock_bh(&qitem_lock);
tasklet_kill(&tipc_tasklet);
spin_lock_bh(&qitem_lock);
list_for_each_safe(l, n, &signal_queue_head) {
item = list_entry(l, struct queue_item, next_signal);
list_del(&item->next_signal);
kmem_cache_free(tipc_queue_item_cache, item);
}
spin_unlock_bh(&qitem_lock);
kmem_cache_destroy(tipc_queue_item_cache);
}
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