diff --git a/arch/arm/src/armv7-a/arm_cpustart.c b/arch/arm/src/armv7-a/arm_cpustart.c
index 012d2e438e..d63c035db6 100644
--- a/arch/arm/src/armv7-a/arm_cpustart.c
+++ b/arch/arm/src/armv7-a/arm_cpustart.c
@@ -43,6 +43,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/sched.h>
+#include <nuttx/sched_note.h>
 
 #include "up_internal.h"
 #include "cp15_cacheops.h"
@@ -104,13 +105,18 @@ static inline void arm_registerdump(FAR struct tcb_s *tcb)
 
 int arm_start_handler(int irq, FAR void *context)
 {
-  FAR struct tcb_s *tcb;
+  FAR struct tcb_s *tcb = this_task();
 
   sinfo("CPU%d Started\n", this_cpu());
 
+#ifdef CONFIG_SCHED_INSTRUMENTATION
+  /* Notify that this CPU has started */
+
+  sched_note_cpu_started(tcb);
+#endif
+
   /* Reset scheduler parameters */
 
-  tcb = this_task();
   sched_resume_scheduler(tcb);
 
   /* Dump registers so that we can see what is going to happen on return */
@@ -159,6 +165,12 @@ int up_cpu_start(int cpu)
 
   DEBUGASSERT(cpu >= 0 && cpu < CONFIG_SMP_NCPUS && cpu != this_cpu());
 
+#ifdef CONFIG_SCHED_INSTRUMENTATION
+  /* Notify of the start event */
+
+  sched_note_cpu_start(this_task(), cpu);
+#endif
+
   /* Make the content of CPU0 L1 cache has been written to coherent L2 */
 
   cp15_clean_dcache(CONFIG_RAM_START, CONFIG_RAM_END - 1);
diff --git a/arch/arm/src/sam34/sam4cm_cpustart.c b/arch/arm/src/sam34/sam4cm_cpustart.c
index 44c8d9508c..7a5c62f0fc 100644
--- a/arch/arm/src/sam34/sam4cm_cpustart.c
+++ b/arch/arm/src/sam34/sam4cm_cpustart.c
@@ -47,6 +47,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/spinlock.h>
+#include <nuttx/sched_note.h>
 
 #include "nvic.h"
 #include "up_arch.h"
@@ -124,6 +125,12 @@ static void cpu1_boot(void)
 
   spin_unlock(&g_cpu1_boot);
 
+#ifdef CONFIG_SCHED_INSTRUMENTATION
+  /* Notify that this CPU has started */
+
+  sched_note_cpu_started(this_task());
+#endif
+
   /* Then transfer control to the IDLE task */
 
   (void)os_idle_task(0, NULL);
@@ -163,7 +170,15 @@ int up_cpu_start(int cpu)
   DPRINTF("cpu=%d\n",cpu);
 
   if (cpu != 1)
-    return -1;
+    {
+      return -EINVAL;
+    }
+
+#ifdef CONFIG_SCHED_INSTRUMENTATION
+  /* Notify of the start event */
+
+  sched_note_cpu_start(this_task(), cpu);
+#endif
 
   /* Reset coprocessor */
 
diff --git a/arch/xtensa/src/esp32/esp32_cpustart.c b/arch/xtensa/src/esp32/esp32_cpustart.c
index 3a603579b6..90998f107c 100644
--- a/arch/xtensa/src/esp32/esp32_cpustart.c
+++ b/arch/xtensa/src/esp32/esp32_cpustart.c
@@ -47,6 +47,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/sched.h>
 #include <nuttx/semaphore.h>
+#include <nuttx/sched_note.h>
 
 #include "sched/sched.h"
 #include "xtensa.h"
@@ -152,11 +153,17 @@ static inline void xtensa_attach_fromcpu0_interrupt(void)
 
 int xtensa_start_handler(int irq, FAR void *context)
 {
-  FAR struct tcb_s *tcb;
+  FAR struct tcb_s *tcb = this_task();
   int i;
 
   sinfo("CPU%d Started\n", up_cpu_index());
 
+#ifdef CONFIG_SCHED_INSTRUMENTATION
+  /* Notify that this CPU has started */
+
+  sched_note_cpu_started(tcb);
+#endif
+
   /* Handle interlock*/
 
   g_appcpu_started = true;
@@ -164,7 +171,6 @@ int xtensa_start_handler(int irq, FAR void *context)
 
   /* Reset scheduler parameters */
 
-  tcb = this_task();
   sched_resume_scheduler(tcb);
 
   /* Move CPU0 exception vectors to IRAM */
@@ -261,6 +267,12 @@ int up_cpu_start(int cpu)
 
       sinfo("Starting CPU%d\n", cpu);
 
+#ifdef CONFIG_SCHED_INSTRUMENTATION
+      /* Notify of the start event */
+
+      sched_note_cpu_start(this_task(), cpu);
+#endif
+
       /* The waitsem semaphore is used for signaling and, hence, should not
        * have priority inheritance enabled.
        */
diff --git a/configs/sabre-6quad/README.txt b/configs/sabre-6quad/README.txt
index ab4d4b5fa0..dda5ef7620 100644
--- a/configs/sabre-6quad/README.txt
+++ b/configs/sabre-6quad/README.txt
@@ -118,6 +118,9 @@ Status
 2016-12-01:  I committed a completely untest SPI driver.  This was taken
   directly from the i.MX1 and is most certainly not ready for use yet.
 
+2016-12-07:  Just a note to remind myself.  The PL310 L2 cache has *not*
+  yet been enbled.
+
 Platform Features
 =================
 
diff --git a/configs/sabre-6quad/src/imx_bringup.c b/configs/sabre-6quad/src/imx_bringup.c
index 13f1742c15..6c3f4949ba 100644
--- a/configs/sabre-6quad/src/imx_bringup.c
+++ b/configs/sabre-6quad/src/imx_bringup.c
@@ -40,7 +40,8 @@
 #include <nuttx/config.h>
 
 #include <sys/types.h>
-#include <debug.h>
+#include <sys/mount.h>
+#include <syslog.h>
 
 #include "sabre-6quad.h"
 
@@ -58,5 +59,18 @@
 
 int imx_bringup(void)
 {
+  int ret;
+
+#ifdef CONFIG_FS_PROCFS
+  /* Mount the procfs file system */
+
+  ret = mount(NULL, "/proc", "procfs", 0, NULL);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: Failed to mount procfs at /proc: %d\n", ret);
+    }
+#endif
+
+  UNUSED(ret);
   return OK;
 }
diff --git a/include/nuttx/sched_note.h b/include/nuttx/sched_note.h
index c27e931deb..47c028b617 100644
--- a/include/nuttx/sched_note.h
+++ b/include/nuttx/sched_note.h
@@ -82,6 +82,8 @@ enum note_type_e
   NOTE_RESUME
 #ifdef CONFIG_SMP
   ,
+  NOTE_CPU_START,
+  NOTE_CPU_STARTED,
   NOTE_CPU_PAUSE,
   NOTE_CPU_PAUSED,
   NOTE_CPU_RESUME,
@@ -153,6 +155,22 @@ struct note_resume_s
 };
 
 #ifdef CONFIG_SMP
+
+/* This is the specific form of the NOTE_CPU_START note */
+
+struct note_cpu_start_s
+{
+  struct note_common_s ncs_cmn; /* Common note parameters */
+  uint8_t ncs_target;           /* CPU being started */
+};
+
+/* This is the specific form of the NOTE_CPU_STARTED note */
+
+struct note_cpu_started_s
+{
+  struct note_common_s ncs_cmn; /* Common note parameters */
+};
+
 /* This is the specific form of the NOTE_CPU_PAUSE note */
 
 struct note_cpu_pause_s
@@ -248,11 +266,15 @@ void sched_note_suspend(FAR struct tcb_s *tcb);
 void sched_note_resume(FAR struct tcb_s *tcb);
 
 #ifdef CONFIG_SMP
+void sched_note_cpu_start(FAR struct tcb_s *tcb, int cpu);
+void sched_note_cpu_started(FAR struct tcb_s *tcb);
 void sched_note_cpu_pause(FAR struct tcb_s *tcb, int cpu);
 void sched_note_cpu_paused(FAR struct tcb_s *tcb);
 void sched_note_cpu_resume(FAR struct tcb_s *tcb, int cpu);
 void sched_note_cpu_resumed(FAR struct tcb_s *tcb);
 #else
+#  define sched_note_cpu_start(t,c)
+#  define sched_note_cpu_started(t)
 #  define sched_note_cpu_pause(t,c)
 #  define sched_note_cpu_paused(t)
 #  define sched_note_cpu_resume(t,c)
@@ -353,6 +375,8 @@ int note_register(void);
 #  define sched_note_stop(t)
 #  define sched_note_suspend(t)
 #  define sched_note_resume(t)
+#  define sched_note_cpu_start(t,c)
+#  define sched_note_cpu_started(t)
 #  define sched_note_cpu_pause(t,c)
 #  define sched_note_cpu_paused(t)
 #  define sched_note_cpu_resume(t,c)
diff --git a/sched/sched/sched_note.c b/sched/sched/sched_note.c
index 22d87b8264..cf7b475c61 100644
--- a/sched/sched/sched_note.c
+++ b/sched/sched/sched_note.c
@@ -435,6 +435,33 @@ void sched_note_resume(FAR struct tcb_s *tcb)
 }
 
 #ifdef CONFIG_SMP
+void sched_note_cpu_start(FAR struct tcb_s *tcb, int cpu)
+{
+  struct note_cpu_start_s note;
+
+  /* Format the note */
+
+  note_common(tcb, &note.ncs_cmn, sizeof(struct note_cpu_start_s), NOTE_CPU_START);
+  note.ncs_target = (uint8_t)cpu;
+
+  /* Add the note to circular buffer */
+
+  note_add((FAR const uint8_t *)&note, sizeof(struct note_cpu_start_s));
+}
+
+void sched_note_cpu_started(FAR struct tcb_s *tcb)
+{
+  struct note_cpu_started_s note;
+
+  /* Format the note */
+
+  note_common(tcb, &note.ncs_cmn, sizeof(struct note_cpu_started_s), NOTE_CPU_STARTED);
+
+  /* Add the note to circular buffer */
+
+  note_add((FAR const uint8_t *)&note, sizeof(struct note_cpu_started_s));
+}
+
 void sched_note_cpu_pause(FAR struct tcb_s *tcb, int cpu)
 {
   struct note_cpu_pause_s note;