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

From: Alexander Gordeev
Date: Mon Oct 06 2014 - 11:17:59 EST


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@xxxxxxxxxx>
Cc: linux-ide@xxxxxxxxxxxxxxx
---
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@xxxxxxxxxx
--
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