[PATCHv3 RFC 3/4] sparc64: Avoid irqsave/restore on vio.lock if in_softirq()
From: Sowmini Varadhan <hidden>
Date: 2014-10-15 16:43:23
Also in:
sparclinux
Subsystem:
sparc + ultrasparc (sparc/sparc64), the rest · Maintainers:
"David S. Miller", Andreas Larsson, Linus Torvalds
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 <redacted> --- arch/sparc/kernel/viohs.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
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);
--
1.8.4.2