diff options
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 8 | ||||
| -rw-r--r-- | drivers/usb/host/ehci-q.c | 82 | ||||
| -rw-r--r-- | drivers/usb/host/ehci.h | 3 |
3 files changed, 45 insertions, 48 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 4ee62bef372..2902199fa8f 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -90,7 +90,8 @@ 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 (DIV_ROUND_UP(HZ, 200) + 1) + /* 200-ms async qh unlink delay */ /* Initial IRQ latency: faster than hw default */ static int log2_irq_thresh = 0; // 0 to 6 @@ -148,10 +149,7 @@ 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 5d6bc624c96..9bf3c0d983c 100644 --- a/drivers/usb/host/ehci-q.c +++ b/drivers/usb/host/ehci-q.c @@ -1231,6 +1231,8 @@ static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh) prev->hw->hw_next = qh->hw->hw_next; prev->qh_next = qh->qh_next; + if (ehci->qh_scan_next == qh) + ehci->qh_scan_next = qh->qh_next.qh; wmb (); /* If the controller isn't running, we don't have to wait for it */ @@ -1256,53 +1258,49 @@ 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); timer_action_done (ehci, TIMER_ASYNC_SHRINK); -rescan: stopped = !HC_IS_RUNNING(ehci_to_hcd(ehci)->state); - qh = ehci->async->qh_next.qh; - if (likely (qh != NULL)) { - do { - /* clean any finished work for this qh */ - if (!list_empty(&qh->qtd_list) && (stopped || - qh->stamp != ehci->stamp)) { - int temp; - - /* unlinks could happen here; completion - * reporting drops the lock. rescan using - * the latest schedule, but don't rescan - * qhs we already finished (no looping) - * unless the controller is stopped. - */ - qh = qh_get (qh); - qh->stamp = ehci->stamp; - temp = qh_completions (ehci, qh); - if (qh->needs_rescan) - unlink_async(ehci, qh); - qh_put (qh); - if (temp != 0) { - goto rescan; - } - } - /* unlink idle entries, reducing DMA usage as well - * as HCD schedule-scanning costs. delay for any qh - * we just scanned, there's a not-unusual case that it - * doesn't stay idle for long. - * (plus, avoids some kind of re-activation race.) + ehci->qh_scan_next = ehci->async->qh_next.qh; + while (ehci->qh_scan_next) { + qh = ehci->qh_scan_next; + ehci->qh_scan_next = qh->qh_next.qh; + rescan: + /* clean any finished work for this qh */ + if (!list_empty(&qh->qtd_list)) { + int temp; + + /* + * Unlinks could happen here; completion reporting + * drops the lock. That's why ehci->qh_scan_next + * always holds the next qh to scan; if the next qh + * gets unlinked then ehci->qh_scan_next is adjusted + * in start_unlink_async(). */ - if (list_empty(&qh->qtd_list) - && qh->qh_state == QH_STATE_LINKED) { - if (!ehci->reclaim && (stopped || - ((ehci->stamp - qh->stamp) & 0x1fff) - >= EHCI_SHRINK_FRAMES * 8)) - start_unlink_async(ehci, qh); - else - action = TIMER_ASYNC_SHRINK; - } + qh = qh_get(qh); + temp = qh_completions(ehci, qh); + if (qh->needs_rescan) + unlink_async(ehci, qh); + qh->unlink_time = jiffies + EHCI_SHRINK_JIFFIES; + qh_put(qh); + if (temp != 0) + goto rescan; + } - qh = qh->qh_next.qh; - } while (qh); + /* unlink idle entries, reducing DMA usage as well + * as HCD schedule-scanning costs. delay for any qh + * we just scanned, there's a not-unusual case that it + * 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 && (stopped || + time_after_eq(jiffies, qh->unlink_time))) + start_unlink_async(ehci, qh); + else + action = TIMER_ASYNC_SHRINK; + } } if (action == TIMER_ASYNC_SHRINK) timer_action (ehci, TIMER_ASYNC_SHRINK); diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h index fa3129fe1ee..e4feec3457f 100644 --- a/drivers/usb/host/ehci.h +++ b/drivers/usb/host/ehci.h @@ -75,6 +75,7 @@ struct ehci_hcd { /* one per controller */ struct ehci_qh *async; struct ehci_qh *dummy; /* For AMD quirk use */ struct ehci_qh *reclaim; + struct ehci_qh *qh_scan_next; unsigned scanning : 1; /* periodic schedule support */ @@ -119,7 +120,6 @@ struct ehci_hcd { /* one per controller */ struct timer_list iaa_watchdog; struct timer_list watchdog; unsigned long actions; - unsigned stamp; unsigned periodic_stamp; unsigned random_frame; unsigned long next_statechange; @@ -345,6 +345,7 @@ struct ehci_qh { struct ehci_qh *reclaim; /* next to reclaim */ struct ehci_hcd *ehci; + unsigned long unlink_time; /* * Do NOT use atomic operations for QH refcounting. On some CPUs |