Quoting Gerd Hoffmann (2013-08-28 07:43:01)
> Respect the interval for interrupt endpoints, so we don't finish
> transfers as fast as possible but at the rate configured by the guest.
>
> Fixes guest deadlocks triggered by interrupt storms.
>
> Cc:
Was this meant to go to qemu-stable?
> Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
> ---
> hw/usb/hcd-xhci.c | 44 +++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 37 insertions(+), 7 deletions(-)
>
> diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
> index 3826979..2e2eb55 100644
> --- a/hw/usb/hcd-xhci.c
> +++ b/hw/usb/hcd-xhci.c
> @@ -355,6 +355,7 @@ typedef struct XHCITransfer {
> unsigned int streamid;
> bool in_xfer;
> bool iso_xfer;
> + bool timed_xfer;
>
> unsigned int trb_count;
> unsigned int trb_alloced;
> @@ -1820,6 +1821,7 @@ static int xhci_fire_ctl_transfer(XHCIState *xhci,
> XHCITransfer *xfer)
>
> xfer->in_xfer = bmRequestType & USB_DIR_IN;
> xfer->iso_xfer = false;
> + xfer->timed_xfer = false;
>
> if (xhci_setup_packet(xfer) < 0) {
> return -1;
> @@ -1835,6 +1837,17 @@ static int xhci_fire_ctl_transfer(XHCIState *xhci,
> XHCITransfer *xfer)
> return 0;
> }
>
> +static void xhci_calc_intr_kick(XHCIState *xhci, XHCITransfer *xfer,
> + XHCIEPContext *epctx, uint64_t mfindex)
> +{
> + uint64_t asap = ((mfindex + epctx->interval - 1) &
> + ~(epctx->interval-1));
> + uint64_t kick = epctx->mfindex_last + epctx->interval;
> +
> + assert(epctx->interval != 0);
> + xfer->mfindex_kick = MAX(asap, kick);
> +}
> +
> static void xhci_calc_iso_kick(XHCIState *xhci, XHCITransfer *xfer,
> XHCIEPContext *epctx, uint64_t mfindex)
> {
> @@ -1857,8 +1870,8 @@ static void xhci_calc_iso_kick(XHCIState *xhci,
> XHCITransfer *xfer,
> }
> }
>
> -static void xhci_check_iso_kick(XHCIState *xhci, XHCITransfer *xfer,
> - XHCIEPContext *epctx, uint64_t mfindex)
> +static void xhci_check_intr_iso_kick(XHCIState *xhci, XHCITransfer *xfer,
> + XHCIEPContext *epctx, uint64_t mfindex)
> {
> if (xfer->mfindex_kick > mfindex) {
> timer_mod(epctx->kick_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
> @@ -1883,18 +1896,30 @@ static int xhci_submit(XHCIState *xhci, XHCITransfer
> *xfer, XHCIEPContext *epctx
> switch(epctx->type) {
> case ET_INTR_OUT:
> case ET_INTR_IN:
> + xfer->pkts = 0;
> + xfer->iso_xfer = false;
> + xfer->timed_xfer = true;
> + mfindex = xhci_mfindex_get(xhci);
> + xhci_calc_intr_kick(xhci, xfer, epctx, mfindex);
> + xhci_check_intr_iso_kick(xhci, xfer, epctx, mfindex);
> + if (xfer->running_retry) {
> + return -1;
> + }
> + break;
> case ET_BULK_OUT:
> case ET_BULK_IN:
> xfer->pkts = 0;
> xfer->iso_xfer = false;
> + xfer->timed_xfer = false;
> break;
> case ET_ISO_OUT:
> case ET_ISO_IN:
> xfer->pkts = 1;
> xfer->iso_xfer = true;
> + xfer->timed_xfer = true;
> mfindex = xhci_mfindex_get(xhci);
> xhci_calc_iso_kick(xhci, xfer, epctx, mfindex);
> - xhci_check_iso_kick(xhci, xfer, epctx, mfindex);
> + xhci_check_intr_iso_kick(xhci, xfer, epctx, mfindex);
> if (xfer->running_retry) {
> return -1;
> }
> @@ -1955,13 +1980,18 @@ static void xhci_kick_ep(XHCIState *xhci, unsigned
> int slotid,
>
> trace_usb_xhci_xfer_retry(xfer);
> assert(xfer->running_retry);
> - if (xfer->iso_xfer) {
> - /* retry delayed iso transfer */
> + if (xfer->timed_xfer) {
> + /* time to kick the transfer? */
> mfindex = xhci_mfindex_get(xhci);
> - xhci_check_iso_kick(xhci, xfer, epctx, mfindex);
> + xhci_check_intr_iso_kick(xhci, xfer, epctx, mfindex);
> if (xfer->running_retry) {
> return;
> }
> + xfer->timed_xfer = 0;
> + xfer->running_retry = 1;
> + }
> + if (xfer->iso_xfer) {
> + /* retry iso transfer */
> if (xhci_setup_packet(xfer) < 0) {
> return;
> }
> @@ -2047,7 +2077,7 @@ static void xhci_kick_ep(XHCIState *xhci, unsigned int
> slotid,
> epctx->next_xfer = (epctx->next_xfer + 1) % TD_QUEUE;
> ep = xfer->packet.ep;
> } else {
> - if (!xfer->iso_xfer) {
> + if (!xfer->timed_xfer) {
> fprintf(stderr, "xhci: error firing data transfer\n");
> }
> }
> --
> 1.8.3.1
