From: Yijing Wang <wangyijing@huawei.com>
Date: Tue, 8 Jul 2014 02:08:55 +0000 (+0800)
Subject: PCI/MSI: Retrieve first MSI IRQ from msi_desc rather than pci_dev
X-Git-Tag: firefly_0821_release~176^2~3365^2~1^6~2
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a281b788d6070526c63b7bbc43dcbe5906d3f487;p=firefly-linux-kernel-4.4.55.git

PCI/MSI: Retrieve first MSI IRQ from msi_desc rather than pci_dev

Retrieve the first MSI IRQ to compute the MSI index from struct msi_desc
rather than the struct pci_dev to avoid an additional memory access.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index dd0a259e3aaa..5bb99213f55d 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -235,7 +235,7 @@ static void msi_set_mask_bit(struct irq_data *data, u32 flag)
 		msix_mask_irq(desc, flag);
 		readl(desc->mask_base);		/* Flush write to device */
 	} else {
-		unsigned offset = data->irq - desc->dev->irq;
+		unsigned offset = data->irq - desc->irq;
 		msi_mask_irq(desc, 1 << offset, flag << offset);
 	}
 }