Add boot_hrtime to global and zone kstats.

*** 20,29 ****
--- 20,30 ----
   */
  /*
   * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
   * Copyright 2014, Joyent, Inc. All rights reserved.
   * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
+  * Copyright 2016 Garrett D'Amore
   */
  
  /*
   * Kernel statistics framework
   */
*** 146,155 ****
--- 147,157 ----
  extern  uint_t          pollstats_ndata;
  
  extern  int     vac;
  extern  uint_t  nproc;
  extern  time_t  boot_time;
+ extern  hrtime_t        boot_hrtime;
  extern  sysinfo_t       sysinfo;
  extern  vminfo_t        vminfo;
  
  struct {
          kstat_named_t ncpus;
*** 160,169 ****
--- 162,172 ----
          kstat_named_t nproc;
          kstat_named_t avenrun_1min;
          kstat_named_t avenrun_5min;
          kstat_named_t avenrun_15min;
          kstat_named_t boot_time;
+         kstat_named_t boot_hrtime;
          kstat_named_t nsec_per_tick;
  } system_misc_kstat = {
          { "ncpus",              KSTAT_DATA_UINT32 },
          { "lbolt",              KSTAT_DATA_UINT32 },
          { "deficit",            KSTAT_DATA_UINT32 },
*** 172,181 ****
--- 175,185 ----
          { "nproc",              KSTAT_DATA_UINT32 },
          { "avenrun_1min",       KSTAT_DATA_UINT32 },
          { "avenrun_5min",       KSTAT_DATA_UINT32 },
          { "avenrun_15min",      KSTAT_DATA_UINT32 },
          { "boot_time",          KSTAT_DATA_UINT32 },
+         { "boot_hrtime",        KSTAT_DATA_TIME },
          { "nsec_per_tick",      KSTAT_DATA_UINT32 },
  };
  
  struct {
          kstat_named_t physmem;
*** 808,817 ****
--- 812,822 ----
  system_misc_kstat_update(kstat_t *ksp, int rw)
  {
          int myncpus = ncpus;
          int *loadavgp = &avenrun[0];
          time_t zone_boot_time;
+         hrtime_t zone_boot_hrtime;
          clock_t zone_lbolt;
          hrtime_t zone_hrtime;
          size_t zone_nproc;
  
          if (rw == KSTAT_WRITE)
*** 834,845 ****
--- 839,852 ----
  
          if (INGLOBALZONE(curproc)) {
                  zone_boot_time = boot_time;
                  zone_lbolt = ddi_get_lbolt();
                  zone_nproc = nproc;
+                 zone_boot_hrtime = boot_hrtime;
          } else {
                  zone_boot_time = curproc->p_zone->zone_boot_time;
+                 zone_boot_hrtime = curproc->p_zone->zone_boot_hrtime;
  
                  zone_hrtime = gethrtime();
                  zone_lbolt = (clock_t)(NSEC_TO_TICK(zone_hrtime) -
                      NSEC_TO_TICK(curproc->p_zone->zone_zsched->p_mstart));
                  mutex_enter(&curproc->p_zone->zone_nlwps_lock);
*** 856,865 ****
--- 863,873 ----
          system_misc_kstat.avenrun_1min.value.ui32       = (uint32_t)loadavgp[0];
          system_misc_kstat.avenrun_5min.value.ui32       = (uint32_t)loadavgp[1];
          system_misc_kstat.avenrun_15min.value.ui32      = (uint32_t)loadavgp[2];
          system_misc_kstat.boot_time.value.ui32          = (uint32_t)
              zone_boot_time;
+         system_misc_kstat.boot_hrtime.value.t           = zone_boot_hrtime;
          system_misc_kstat.nsec_per_tick.value.ui32      = (uint32_t)
              nsec_per_tick;
          return (0);
  }