)]}'
{
  "commit": "c06d68b814d556cff5a4dc589215f5ed9f0b7fd5",
  "tree": "00c8213bd42c6134d817a1476f4a654a8a51bc33",
  "parents": [
    "d6d98a4d8d2411bca7e15d9c0796bf3bc30c3f21"
  ],
  "author": {
    "name": "Sarah Sharp",
    "email": "sarah.a.sharp@linux.intel.com",
    "time": "Thu Jul 29 22:12:49 2010 -0700"
  },
  "committer": {
    "name": "Greg Kroah-Hartman",
    "email": "gregkh@suse.de",
    "time": "Tue Aug 10 14:35:44 2010 -0700"
  },
  "message": "USB: xhci: Minimize HW event ring dequeue pointer writes.\n\nThe xHCI specification suggests that writing the hardware event ring dequeue\npointer register too often can be an expensive operation for the xHCI hardware\nto manage.  It suggests minimizing the number of writes to that register.\n\nOriginally, the driver wrote the event ring dequeue pointer after each\nevent was processed.  Depending on how the event ring moderation register\nis set up and how fast the transfers are completing, there may be several\nevents processed for each interrupt.  This patch makes the hardware event\nring dequeue pointer be written only once per interrupt.\n\nMake the transfer event handler and port status event handler only write\nthe software event ring dequeue pointer.  Move the updating of the\nhardware event ring dequeue pointer into the interrupt function.  Move the\ncontents of xhci_set_hc_event_deq() into the interrupt handler.  The\ninterrupt handler must clear the event handler busy flag, so it might as\nwell also write the dequeue pointer to the same register.  This eliminates\ntwo 32-bit PCI reads and two 32-bit PCI writes.\n\nReported-by: Andiry Xu \u003candiry.xu@amd.com\u003e\nSigned-off-by: Sarah Sharp \u003csarah.a.sharp@linux.intel.com\u003e\nSigned-off-by: Greg Kroah-Hartman \u003cgregkh@suse.de\u003e\n\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "3b962ba5ef085490e4f12e4a4819ac3ff5b239f1",
      "old_mode": 33188,
      "old_path": "drivers/usb/host/xhci-ring.c",
      "new_id": "7dfd17707d53b34c7caca04d35e5465bc8315d28",
      "new_mode": 33188,
      "new_path": "drivers/usb/host/xhci-ring.c"
    }
  ]
}