From: Tejun Heo <tj@kernel.org>
Date: Mon, 27 Oct 2014 16:00:01 +0000 (-0400)
Subject: Revert "AHCI: Do not acquire ata_host::lock from single IRQ handler"
X-Git-Tag: firefly_0821_release~176^2~2710^2~12
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=03e83cbd34a4602bf0d750e5ff4bf8b7d0e066b2;p=firefly-linux-kernel-4.4.55.git

Revert "AHCI: Do not acquire ata_host::lock from single IRQ handler"

This reverts commit 33fb0d01ce60fe4c0c12c4f0c134c5cdb818ac5a.

18dcf433f3de ("AHCI: Optimize single IRQ interrupt processing") is
scheduled to be reverted.  This is an optimization dependent on the
mentioned commit.  Revert it first.

Signed-off-by: Tejun Heo <tj@kernel.org>
---

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 5eb61c9e63da..3ce3d23e4f97 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -1875,6 +1875,8 @@ 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;
 
@@ -1906,6 +1908,8 @@ 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;