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udlfb: use spin_lock_irq instead of spin_lock_irqsave 

spin_lock_irqsave and spin_unlock_irqrestore is inteded to be called from
a context where it is unknown if interrupts are enabled or disabled (such
as interrupt handlers). From a process context, we should call
spin_lock_irq and spin_unlock_irq, that avoids the costly pushf and popf
instructions.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
This commit is contained in:
Mikulas Patocka 2018-07-25 15:41:57 +02:00 committed by Bartlomiej Zolnierkiewicz
parent 037dde4113
commit cb782a3fa9
1 changed files with 4 additions and 6 deletions
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10
drivers/video/fbdev/udlfb.c
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@ -1855,18 +1855,17 @@ static void dlfb_free_urb_list(struct dlfb_data *dlfb)
struct list_head *node;
struct urb_node *unode;
struct urb *urb;
unsigned long flags;
/* keep waiting and freeing, until we've got 'em all */
while (count--) {
down(&dlfb->urbs.limit_sem);
spin_lock_irqsave(&dlfb->urbs.lock, flags);
spin_lock_irq(&dlfb->urbs.lock);
node = dlfb->urbs.list.next; /* have reserved one with sem */
list_del_init(node);
spin_unlock_irqrestore(&dlfb->urbs.lock, flags);
spin_unlock_irq(&dlfb->urbs.lock);
unode = list_entry(node, struct urb_node, entry);
urb = unode->urb;
@ -1944,7 +1943,6 @@ static struct urb *dlfb_get_urb(struct dlfb_data *dlfb)
int ret;
struct list_head *entry;
struct urb_node *unode;
unsigned long flags;
/* Wait for an in-flight buffer to complete and get re-queued */
ret = down_timeout(&dlfb->urbs.limit_sem, GET_URB_TIMEOUT);
@ -1956,14 +1954,14 @@ static struct urb *dlfb_get_urb(struct dlfb_data *dlfb)
return NULL;
}
spin_lock_irqsave(&dlfb->urbs.lock, flags);
spin_lock_irq(&dlfb->urbs.lock);
BUG_ON(list_empty(&dlfb->urbs.list)); /* reserved one with limit_sem */
entry = dlfb->urbs.list.next;
list_del_init(entry);
dlfb->urbs.available--;
spin_unlock_irqrestore(&dlfb->urbs.lock, flags);
spin_unlock_irq(&dlfb->urbs.lock);
unode = list_entry(entry, struct urb_node, entry);
return unode->urb;