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>

1 files changed, 30 insertions, 43 deletions

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 4b50a02ba114..f9c08d2fe33a 100644
--- 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;