USB: xhci: Performance - move xhci_work() into xhci_irq()

When we move xhci_work() into xhci_irq(), we don't need to read the operational
register status field twice.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 4b50a02..f9c08d2 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2030,48 +2030,6 @@ void xhci_handle_event(struct xhci_hcd *xhci)
        /* Are there more items on the event ring? */
        xhci_handle_event(xhci);
 }
-/*
- * Called in interrupt context when there might be work
- * queued on the event ring
- *
- * xhci->lock must be held by caller.
- */
-static void xhci_work(struct xhci_hcd *xhci)
-{
-       u32 temp;
-       u64 temp_64;
-
-       /*
-        * Clear the op reg interrupt status first,
-        * so we can receive interrupts from other MSI-X interrupters.
-        * Write 1 to clear the interrupt status.
-        */
-       temp = xhci_readl(xhci, &xhci->op_regs->status);
-       temp |= STS_EINT;
-       xhci_writel(xhci, temp, &xhci->op_regs->status);
-       /* FIXME when MSI-X is supported and there are multiple vectors */
-       /* Clear the MSI-X event interrupt status */
-
-       /* Acknowledge the interrupt */
-       temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
-       temp |= 0x3;
-       xhci_writel(xhci, temp, &xhci->ir_set->irq_pending);
-
-       if (xhci->xhc_state & XHCI_STATE_DYING)
-               xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "
-                               "Shouldn't IRQs be disabled?\n");
-       else
-               /* FIXME this should be a delayed service routine
-                * that clears the EHB.
-                */
-               xhci_handle_event(xhci);
-
-       /* Clear the event handler busy flag (RW1C); event ring is empty. */
-       temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
-       xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue);
-       /* Flush posted writes -- FIXME is this necessary? */
-       xhci_readl(xhci, &xhci->ir_set->irq_pending);
-}
 
 /*
  * xHCI spec says we can get an interrupt, and if the HC has an error condition,
@@ -2083,6 +2041,7 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd)
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        u32 temp, temp2;
        union xhci_trb *trb;
+       u64 temp_64;
 
        spin_lock(&xhci->lock);
        trb = xhci->event_ring->dequeue;
@@ -2117,7 +2076,35 @@ hw_died:
                return -ESHUTDOWN;
        }
 
-       xhci_work(xhci);
+       /*
+        * Clear the op reg interrupt status first,
+        * so we can receive interrupts from other MSI-X interrupters.
+        * Write 1 to clear the interrupt status.
+        */
+       temp |= STS_EINT;
+       xhci_writel(xhci, temp, &xhci->op_regs->status);
+       /* FIXME when MSI-X is supported and there are multiple vectors */
+       /* Clear the MSI-X event interrupt status */
+
+       /* Acknowledge the interrupt */
+       temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+       temp |= 0x3;
+       xhci_writel(xhci, temp, &xhci->ir_set->irq_pending);
+
+       if (xhci->xhc_state & XHCI_STATE_DYING)
+               xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "
+                               "Shouldn't IRQs be disabled?\n");
+       else
+               /* FIXME this should be a delayed service routine
+                * that clears the EHB.
+                */
+               xhci_handle_event(xhci);
+
+       /* Clear the event handler busy flag (RW1C); event ring is empty. */
+       temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+       xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue);
+       /* Flush posted writes -- FIXME is this necessary? */
+       xhci_readl(xhci, &xhci->ir_set->irq_pending);
        spin_unlock(&xhci->lock);
 
        return IRQ_HANDLED;