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 dd0a259..5bb9921 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -235,7 +235,7 @@
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);
}
}