[PATCH 7/5] AHCI: Do not acquire ata_host::lock from single IRQ handler

[Alexander Gordeev <agordeev@redhat.com>]

There is no need to acquire ata_host::lock spinlock from
hardware context single IRQ interrupt handler since the
handler does not access host data that could be altered
by concurrent processors.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Cc: linux-ide@vger.kernel.org
---
 drivers/ata/libahci.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 3ce3d23..5eb61c9 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -1875,8 +1875,6 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
 
 	irq_masked = irq_stat & hpriv->port_map;
 
-	spin_lock(&host->lock);
-
 	for (i = 0; i < host->n_ports; i++) {
 		struct ata_port *ap;
 
@@ -1908,8 +1906,6 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
 	 */
 	writel(irq_stat, mmio + HOST_IRQ_STAT);
 
-	spin_unlock(&host->lock);
-
 	VPRINTK("EXIT\n");
 
 	return handled ? IRQ_WAKE_THREAD : IRQ_NONE;
-- 
1.8.3.1

-- 
Regards,
Alexander Gordeev
agordeev@redhat.com