IB/qib: Default some module parameters optimally

Minimize the need for users to have to set module parameters to get
good performance.

The following two parameters are changed:
 - rcvhdrcnt to twice the rcvegrcnt
 - pcie_caps=0x51

The rcvhdrcnt at twice the egrcount allows the preemptive NAK code
during reception to function in 100% of the cases rather than a sender
jiffies-based timeout.

The pcie_caps default of 0x51 will set the proposed MaxPayload and
MaxReceiveReqest to 256 and 4096 respectively.  The capabilities on
the root complex will be used to limit those values.

Reviewed-by: Ram Vepa <ram.vepa@qlogic.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/qib/qib_iba7322.c b/drivers/infiniband/hw/qib/qib_iba7322.c
index e22735402649f31ccbb294984f38a40eb86aac35..41e92089e41b1aafb1fc55dc4c14b573f5e27fe0 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_iba7322.c
+++ b/drivers/infiniband/hw/qib/qib_iba7322.c
@@ -3603,7 +3603,7 @@ static void qib_7322_config_ctxts(struct qib_devdata *dd)
        if (qib_rcvhdrcnt)
                dd->rcvhdrcnt = max(dd->cspec->rcvegrcnt, qib_rcvhdrcnt);
        else
-               dd->rcvhdrcnt = max(dd->cspec->rcvegrcnt,
+               dd->rcvhdrcnt = 2 * max(dd->cspec->rcvegrcnt,
                                    dd->num_pports > 1 ? 1024U : 2048U);
 }
 

diff --git a/drivers/infiniband/hw/qib/qib_pcie.c b/drivers/infiniband/hw/qib/qib_pcie.c
index 97a8bdf68e605267f635edf4423ccfdf366a4971..f695061d688e06ce026c312c79415f04a51aac70 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_pcie.c
+++ b/drivers/infiniband/hw/qib/qib_pcie.c
@@ -560,9 +560,9 @@ static int qib_tune_pcie_coalesce(struct qib_devdata *dd)
  * BIOS may not set PCIe bus-utilization parameters for best performance.
  * Check and optionally adjust them to maximize our throughput.
  */
-static int qib_pcie_caps;
+static int qib_pcie_caps = 0x51;
 module_param_named(pcie_caps, qib_pcie_caps, int, S_IRUGO);
-MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (4lsb), ReadReq (D4..7)");
+MODULE_PARM_DESC(pcie_caps, "Max PCIe tuning: Payload (0..3), ReadReq (4..7)");
 
 static int qib_tune_pcie_caps(struct qib_devdata *dd)
 {