[PATCH 09/21] udl-kms: use spin_lock_irq instead of spin_lock_irqsave
Mikulas Patocka
mpatocka at redhat.com
Sun Jun 3 14:41:02 UTC 2018
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 at redhat.com>
---
drivers/gpu/drm/udl/udl_main.c | 10 ++++------
drivers/gpu/drm/udl/udl_modeset.c | 5 ++---
2 files changed, 6 insertions(+), 9 deletions(-)
Index: linux-4.16.12/drivers/gpu/drm/udl/udl_main.c
===================================================================
--- linux-4.16.12.orig/drivers/gpu/drm/udl/udl_main.c 2018-05-31 11:17:01.000000000 +0200
+++ linux-4.16.12/drivers/gpu/drm/udl/udl_main.c 2018-05-31 11:17:01.000000000 +0200
@@ -170,7 +170,6 @@ static void udl_free_urb_list(struct drm
struct list_head *node;
struct urb_node *unode;
struct urb *urb;
- unsigned long flags;
DRM_DEBUG("Waiting for completes and freeing all render urbs\n");
@@ -178,12 +177,12 @@ static void udl_free_urb_list(struct drm
while (count--) {
down(&udl->urbs.limit_sem);
- spin_lock_irqsave(&udl->urbs.lock, flags);
+ spin_lock_irq(&udl->urbs.lock);
node = udl->urbs.list.next; /* have reserved one with sem */
list_del_init(node);
- spin_unlock_irqrestore(&udl->urbs.lock, flags);
+ spin_unlock_irq(&udl->urbs.lock);
unode = list_entry(node, struct urb_node, entry);
urb = unode->urb;
@@ -268,7 +267,6 @@ struct urb *udl_get_urb(struct drm_devic
struct list_head *entry;
struct urb_node *unode;
struct urb *urb = NULL;
- unsigned long flags;
/* Wait for an in-flight buffer to complete and get re-queued */
ret = down_timeout(&udl->urbs.limit_sem, GET_URB_TIMEOUT);
@@ -279,14 +277,14 @@ struct urb *udl_get_urb(struct drm_devic
goto error;
}
- spin_lock_irqsave(&udl->urbs.lock, flags);
+ spin_lock_irq(&udl->urbs.lock);
BUG_ON(list_empty(&udl->urbs.list)); /* reserved one with limit_sem */
entry = udl->urbs.list.next;
list_del_init(entry);
udl->urbs.available--;
- spin_unlock_irqrestore(&udl->urbs.lock, flags);
+ spin_unlock_irq(&udl->urbs.lock);
unode = list_entry(entry, struct urb_node, entry);
urb = unode->urb;
Index: linux-4.16.12/drivers/gpu/drm/udl/udl_modeset.c
===================================================================
--- linux-4.16.12.orig/drivers/gpu/drm/udl/udl_modeset.c 2018-05-31 11:17:01.000000000 +0200
+++ linux-4.16.12/drivers/gpu/drm/udl/udl_modeset.c 2018-05-31 11:17:01.000000000 +0200
@@ -366,7 +366,6 @@ static int udl_crtc_page_flip(struct drm
{
struct udl_framebuffer *ufb = to_udl_fb(fb);
struct drm_device *dev = crtc->dev;
- unsigned long flags;
struct drm_framebuffer *old_fb = crtc->primary->fb;
if (old_fb) {
@@ -377,10 +376,10 @@ static int udl_crtc_page_flip(struct drm
udl_handle_damage(ufb, 0, 0, fb->width, fb->height);
- spin_lock_irqsave(&dev->event_lock, flags);
+ spin_lock_irq(&dev->event_lock);
if (event)
drm_crtc_send_vblank_event(crtc, event);
- spin_unlock_irqrestore(&dev->event_lock, flags);
+ spin_unlock_irq(&dev->event_lock);
crtc->primary->fb = fb;
return 0;
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