From 78c78517463413f5ed4376db00bd34c6debd7e41 Mon Sep 17 00:00:00 2001
From: root <root@exotica.org.uk>
Date: Mon, 31 Jan 2011 02:38:14 +0000
Subject: [PATCH] reverted: b963801164618e25fbdc0cd452ce49c3628b46c8
 USB: ehci-hcd unlink speedups

---
 drivers/usb/host/ehci-hcd.c |    7 ++-----
 drivers/usb/host/ehci-q.c   |   15 +++++++--------
 2 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index e906280..135f7f9 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -90,7 +90,7 @@ static const char	hcd_name [] = "ehci_hcd";
 #define EHCI_IAA_MSECS		10		/* arbitrary */
 #define EHCI_IO_JIFFIES		(HZ/10)		/* io watchdog > irq_thresh */
 #define EHCI_ASYNC_JIFFIES	(HZ/20)		/* async idle timeout */
-#define EHCI_SHRINK_FRAMES	5		/* async qh unlink delay */
+#define EHCI_SHRINK_JIFFIES	(HZ/200)	/* async qh unlink delay */
 
 /* Initial IRQ latency:  faster than hw default */
 static int log2_irq_thresh = 0;		// 0 to 6
@@ -147,10 +147,7 @@ timer_action(struct ehci_hcd *ehci, enum ehci_timer_action action)
 			break;
 		/* case TIMER_ASYNC_SHRINK: */
 		default:
-			/* add a jiffie since we synch against the
-			 * 8 KHz uframe counter.
-			 */
-			t = DIV_ROUND_UP(EHCI_SHRINK_FRAMES * HZ, 1000) + 1;
+			t = EHCI_SHRINK_JIFFIES;
 			break;
 		}
 		mod_timer(&ehci->watchdog, t + jiffies);
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 233c288..510c27f 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -1260,7 +1260,8 @@ static void scan_async (struct ehci_hcd *ehci)
 	struct ehci_qh		*qh;
 	enum ehci_timer_action	action = TIMER_IO_WATCHDOG;
 
-	ehci->stamp = ehci_readl(ehci, &ehci->regs->frame_index);
+	if (!++(ehci->stamp))
+		ehci->stamp++;
 	timer_action_done (ehci, TIMER_ASYNC_SHRINK);
 rescan:
 	qh = ehci->async->qh_next.qh;
@@ -1293,14 +1294,12 @@ rescan:
 			 * doesn't stay idle for long.
 			 * (plus, avoids some kind of re-activation race.)
 			 */
-			if (list_empty(&qh->qtd_list)
-					&& qh->qh_state == QH_STATE_LINKED) {
-				if (!ehci->reclaim
-					&& ((ehci->stamp - qh->stamp) & 0x1fff)
-						>= (EHCI_SHRINK_FRAMES * 8))
-					start_unlink_async(ehci, qh);
-				else
+			if (list_empty (&qh->qtd_list)) {
+				if (qh->stamp == ehci->stamp)
 					action = TIMER_ASYNC_SHRINK;
+				else if (!ehci->reclaim
+					    && qh->qh_state == QH_STATE_LINKED)
+					start_unlink_async (ehci, qh);
 			}
 
 			qh = qh->qh_next.qh;
-- 
1.5.6.5