diff mbox

[PATCHv4,RFC,3/4] sparc64: Avoid irqsave/restore on vio.lock if in_softirq()

Message ID 20141015180240.GJ11840@oracle.com
State RFC
Delegated to: David Miller
Headers show

Commit Message

Sowmini Varadhan Oct. 15, 2014, 6:02 p.m. UTC 
For NAPIfied drivers , there is no need to
synchronize by doing irqsave/restore on vio.lock in the I/O
path.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
---
 arch/sparc/kernel/viohs.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/arch/sparc/kernel/viohs.c b/arch/sparc/kernel/viohs.c
index 7ef081a..d731586 100644
--- a/arch/sparc/kernel/viohs.c
+++ b/arch/sparc/kernel/viohs.c
@@ -747,10 +747,11 @@  EXPORT_SYMBOL(vio_ldc_free);
 
 void vio_port_up(struct vio_driver_state *vio)
 {
-	unsigned long flags;
+	unsigned long flags = 0;
 	int err, state;
 
-	spin_lock_irqsave(&vio->lock, flags);
+	if (!in_softirq())
+		spin_lock_irqsave(&vio->lock, flags);
 
 	state = ldc_state(vio->lp);
 
@@ -777,7 +778,8 @@  void vio_port_up(struct vio_driver_state *vio)
 		mod_timer(&vio->timer, expires);
 	}
 
-	spin_unlock_irqrestore(&vio->lock, flags);
+	if (!in_softirq())
+		spin_unlock_irqrestore(&vio->lock, flags);
 }
 EXPORT_SYMBOL(vio_port_up);