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author | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2010-07-30 09:12:20 +0400 |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-08-11 01:35:44 +0400 |
commit | 021bff9179c2d19c26599dc3e9134d04cf1c8a3a (patch) | |
tree | 99c7dba0d83e607a2ca9d12e50bd8ee7bad56181 /drivers/usb/host/xhci-mem.c | |
parent | c6ba1c2af2da31ffb57949edbd1dba34f97d1d4b (diff) | |
download | linux-021bff9179c2d19c26599dc3e9134d04cf1c8a3a.tar.xz |
USB: xhci: Performance - move functions that find ep ring.
I've been using perf to measure the top symbols while transferring 1GB of data
on a USB 3.0 drive with dd. This is using the raw disk with /dev/sdb, with a
block size of 1K.
During performance testing, the top symbol was xhci_triad_to_transfer_ring(), a
function that should return immediately if streams are not enabled for an
endpoint. It turned out that the functions to find the endpoint ring was
defined in xhci-mem.c and used in xhci-ring.c and xhci-hcd.c. I moved a copy of
xhci_triad_to_transfer_ring() and xhci_urb_to_transfer_ring() into xhci-ring.c
and declared them static. I also made a static version of
xhci_urb_to_transfer_ring() in xhci.c.
This improved throughput on a 1GB read of the raw disk with dd from
186MB/s to 195MB/s, and perf reported sampling the xhci_triad_to_transfer_ring()
0.06% of the time, rather than 9.26% of the time.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/host/xhci-mem.c')
-rw-r--r-- | drivers/usb/host/xhci-mem.c | 43 |
1 files changed, 0 insertions, 43 deletions
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 7d60d1f4debb..ac57f538f957 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -391,49 +391,6 @@ struct xhci_ring *xhci_stream_id_to_ring( return ep->stream_info->stream_rings[stream_id]; } -struct xhci_ring *xhci_triad_to_transfer_ring(struct xhci_hcd *xhci, - unsigned int slot_id, unsigned int ep_index, - unsigned int stream_id) -{ - struct xhci_virt_ep *ep; - - ep = &xhci->devs[slot_id]->eps[ep_index]; - /* Common case: no streams */ - if (!(ep->ep_state & EP_HAS_STREAMS)) - return ep->ring; - - if (stream_id == 0) { - xhci_warn(xhci, - "WARN: Slot ID %u, ep index %u has streams, " - "but URB has no stream ID.\n", - slot_id, ep_index); - return NULL; - } - - if (stream_id < ep->stream_info->num_streams) - return ep->stream_info->stream_rings[stream_id]; - - xhci_warn(xhci, - "WARN: Slot ID %u, ep index %u has " - "stream IDs 1 to %u allocated, " - "but stream ID %u is requested.\n", - slot_id, ep_index, - ep->stream_info->num_streams - 1, - stream_id); - return NULL; -} - -/* Get the right ring for the given URB. - * If the endpoint supports streams, boundary check the URB's stream ID. - * If the endpoint doesn't support streams, return the singular endpoint ring. - */ -struct xhci_ring *xhci_urb_to_transfer_ring(struct xhci_hcd *xhci, - struct urb *urb) -{ - return xhci_triad_to_transfer_ring(xhci, urb->dev->slot_id, - xhci_get_endpoint_index(&urb->ep->desc), urb->stream_id); -} - #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING static int xhci_test_radix_tree(struct xhci_hcd *xhci, unsigned int num_streams, |