intel_mp: Poll more frequently for linkup

This patch lowers the link-up poll period from 2 seconds to 0.1
second, for faster reactions on link state change.  It also makes the
82599 linkup wait loop just wait on link state change, like the old
Intel82599 driver, instead of also doing reset logic in the wait loop.

src/apps/intel_mp/README.md

@@ -49,6 +49,12 @@ light or not. The default is `false`.
 *Optional* Number of seconds `new` waits for the device to come up. The default
 is 120.
 
+— Key **linkup_wait_recheck**
+
+*Optional* If the `linkup_wait` option is true, the number of seconds
+to sleep between checking the link state again.  The default is 0.1
+seconds.
+
 — Key **mtu**
 
 *Optional* The maximum packet length sent or received, excluding the trailing

src/apps/intel_mp/intel_mp.lua

@@ -257,6 +257,7 @@ Intel = {
       mtu = {default=9014},
       rssseed = {default=314159},
       linkup_wait = {default=120},
+      linkup_wait_recheck = {default=0.1},
       wait_for_link = {default=false},
       master_stats = {default=true},
       run_stats = {default=false}
@@ -291,6 +292,8 @@ function Intel:new (conf)
       mtu = conf.mtu or self.config.mtu.default,
       rssseed = conf.rssseed or self.config.mtu.default,
       linkup_wait = conf.linkup_wait or self.config.linkup_wait.default,
+      linkup_wait_recheck =
+         conf.linkup_wait_recheck or self.config.linkup_wait_recheck.default,
       wait_for_link = conf.wait_for_link
    }
 
@@ -757,10 +760,10 @@ function Intel1g:init ()
    self.r.CTRL_EXT:set( bits { AutoSpeedDetect = 12, DriverLoaded = 28 })
    self.r.RLPML(self.mtu + 4) -- mtu + crc
    self:unlock_sw_sem()
-   for i=1, math.floor(self.linkup_wait/2) do
+   for i=1, math.floor(self.linkup_wait/self.linkup_wait_recheck) do
       if self:link_status() then break end
       if not self.wait_for_link then break end
-      C.usleep(2000000)
+      C.usleep(math.floor(self.linkup_wait_recheck * 1e6))
    end
 end
 
@@ -866,24 +869,24 @@ function Intel82599:init ()
    pci.unbind_device_from_linux(self.pciaddress)
    pci.set_bus_master(self.pciaddress, true)
 
-   for i=1,math.floor(self.linkup_wait/2) do
-      self:disable_interrupts()
-      local reset = bits{ LinkReset=3, DeviceReset=26 }
-      self.r.CTRL(reset)
-      C.usleep(1000)
-      self.r.CTRL:wait(reset, 0)
-      self.r.EEC:wait(bits{AutoreadDone=9})           -- 3.
-      self.r.RDRXCTL:wait(bits{DMAInitDone=3})        -- 4.
-
-      -- 4.6.4.2
-      -- 3.7.4.2
-      self.r.AUTOC:set(bits { LMS0 = 13, LMS1 = 14 })
-      self.r.AUTOC2(0)
-      self.r.AUTOC2:set(bits { tenG_PMA_PMD_Serial = 17 })
-      self.r.AUTOC:set(bits{restart_AN=12})
-      C.usleep(2000000)
+   self:disable_interrupts()
+   local reset = bits{ LinkReset=3, DeviceReset=26 }
+   self.r.CTRL(reset)
+   C.usleep(1000)
+   self.r.CTRL:wait(reset, 0)
+   self.r.EEC:wait(bits{AutoreadDone=9})           -- 3.
+   self.r.RDRXCTL:wait(bits{DMAInitDone=3})        -- 4.
+
+   -- 4.6.4.2
+   -- 3.7.4.2
+   self.r.AUTOC:set(bits { LMS0 = 13, LMS1 = 14 })
+   self.r.AUTOC2(0)
+   self.r.AUTOC2:set(bits { tenG_PMA_PMD_Serial = 17 })
+   self.r.AUTOC:set(bits{restart_AN=12})
+   for i=1,math.floor(self.linkup_wait/self.linkup_wait_recheck) do
       if self:link_status() then break end
       if not self.wait_for_link then break end
+      C.usleep(math.floor(self.linkup_wait_recheck * 1e6))
    end
 
    -- 4.6.7