1 files changed, 58 insertions, 33 deletions

diff --git a/driver/gator_main.c b/driver/gator_main.c
index 91744ad..36e951b 100644
--- a/driver/gator_main.c
+++ b/driver/gator_main.c
@@ -7,7 +7,7 @@
  *
  */
 
-static unsigned long gator_protocol_version = 6;
+static unsigned long gator_protocol_version = 7;
 
 #include <linux/slab.h>
 #include <linux/cpu.h>
@@ -17,6 +17,8 @@ static unsigned long gator_protocol_version = 6;
 #include <linux/hardirq.h>
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
+#include <linux/suspend.h>
+#include <asm/stacktrace.h>
 #include <asm/uaccess.h>
 
 #include "gator.h"
@@ -51,7 +53,7 @@ static unsigned long gator_protocol_version = 6;
 /******************************************************************************
  * DEFINES
  ******************************************************************************/
-#define TIMER_BUFFER_SIZE_DEFAULT       (256*1024)
+#define TIMER_BUFFER_SIZE_DEFAULT       (512*1024)
 #define EVENT_BUFFER_SIZE_DEFAULT       (128*1024)
 
 #define NO_COOKIE                               0UL
@@ -267,11 +269,12 @@ static void gator_add_trace(int cpu, int buftype, unsigned int address)
 
 static void gator_add_sample(int cpu, int buftype, struct pt_regs * const regs)
 {
-        struct module *mod;
-        unsigned int addr, cookie = 0;
         int inKernel = regs ? !user_mode(regs) : 1;
         unsigned long exec_cookie = inKernel ? NO_COOKIE : get_exec_cookie(cpu, buftype, current);
 
+        if (!regs)
+                return;
+
         gator_buffer_write_packed_int(cpu, buftype, MESSAGE_START_BACKTRACE);
         gator_buffer_write_packed_int64(cpu, buftype, gator_get_time());
         gator_buffer_write_packed_int(cpu, buftype, exec_cookie);
@@ -279,25 +282,15 @@ static void gator_add_sample(int cpu, int buftype, struct pt_regs * const regs)
         gator_buffer_write_packed_int(cpu, buftype, (unsigned int)current->pid);
         gator_buffer_write_packed_int(cpu, buftype, inKernel);
 
-        // get_irq_regs() will return NULL outside of IRQ context (e.g. nested IRQ)
-        if (regs) {
-                if (inKernel) {
-                        addr = PC_REG;
-                        mod = __module_address(addr);
-                        if (mod) {
-                                cookie = get_cookie(cpu, buftype, current, NULL, mod, true);
-                                addr = addr - (unsigned long)mod->module_core;
-                        }
-                        gator_buffer_write_packed_int(cpu, buftype, addr & ~1);
-                        gator_buffer_write_packed_int(cpu, buftype, cookie);
-                } else {
-                        // Cookie+PC
-                        gator_add_trace(cpu, buftype, PC_REG);
-
-                        // Backtrace
-                        if (gator_backtrace_depth)
-                                arm_backtrace_eabi(cpu, buftype, regs, gator_backtrace_depth);
-                }
+        if (inKernel) {
+                kernel_backtrace(cpu, buftype, regs);
+        } else {
+                // Cookie+PC
+                gator_add_trace(cpu, buftype, PC_REG);
+
+                // Backtrace
+                if (gator_backtrace_depth)
+                        arm_backtrace_eabi(cpu, buftype, regs, gator_backtrace_depth);
         }
 
         gator_buffer_write_packed_int(cpu, buftype, MESSAGE_END_BACKTRACE);
@@ -352,11 +345,12 @@ static void gator_timer_interrupt(void)
                         }
                 } else if (gi->read64) {
                         len = gi->read64(&buffer64);
-                        if (len > 0)
+                        if (len > 0) {
                                 gator_buffer_write_packed_int(cpu, buftype, len);
                                 for (i = 0; i < len; i++) {
                                         gator_buffer_write_packed_int64(cpu, buftype, buffer64[i]);
                                 }
+                        }
                 }
         }
         gator_buffer_write_packed_int(cpu, buftype, 0);
@@ -460,29 +454,28 @@ static uint64_t gator_get_time(void)
         struct timespec ts;
         uint64_t timestamp;
 
-        ktime_get_ts(&ts);
+        getnstimeofday(&ts);
         timestamp = timespec_to_ns(&ts);
 
         return timestamp;
 }
 
 /******************************************************************************
- * cpu online notifier
+ * cpu online and pm notifiers
  ******************************************************************************/
-static int __cpuinit gator_cpu_notify(struct notifier_block *self,
-                                                                                        unsigned long action, void *hcpu)
+static int __cpuinit gator_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
 {
         long cpu = (long)hcpu;
 
         switch (action) {
-                case CPU_ONLINE:
-                case CPU_ONLINE_FROZEN:
-                        smp_call_function_single(cpu, __gator_timer_online, NULL, 1);
-                        break;
                 case CPU_DOWN_PREPARE:
                 case CPU_DOWN_PREPARE_FROZEN:
                         smp_call_function_single(cpu, __gator_timer_offline, NULL, 1);
                         break;
+                case CPU_ONLINE:
+                case CPU_ONLINE_FROZEN:
+                        smp_call_function_single(cpu, __gator_timer_online, NULL, 1);
+                        break;
         }
 
         return NOTIFY_OK;
@@ -492,13 +485,45 @@ static struct notifier_block __refdata gator_cpu_notifier = {
         .notifier_call = gator_cpu_notify,
 };
 
+// n.b. calling "on_each_cpu" only runs on those that are online
+// Registered linux events are not disabled, so their counters will continue to collect
+static int gator_pm_notify(struct notifier_block *nb, unsigned long event, void *dummy)
+{
+        switch (event) {
+                case PM_HIBERNATION_PREPARE:
+                case PM_SUSPEND_PREPARE:
+                        unregister_hotcpu_notifier(&gator_cpu_notifier);
+                        unregister_scheduler_tracepoints();
+                        on_each_cpu(trace_sched_insert_idle, NULL, 1);
+                        on_each_cpu(__gator_timer_offline, NULL, 1);
+                        break;
+                case PM_POST_HIBERNATION:
+                case PM_POST_SUSPEND:
+                        on_each_cpu(__gator_timer_online, NULL, 1);
+                        register_scheduler_tracepoints();
+                        register_hotcpu_notifier(&gator_cpu_notifier);
+                        break;
+        }
+
+        return NOTIFY_OK;
+}
+
+static struct notifier_block gator_pm_notifier = {
+        .notifier_call = gator_pm_notify,
+};
+
 static int gator_notifier_start(void)
 {
-        return register_hotcpu_notifier(&gator_cpu_notifier);
+        int retval;
+        retval = register_hotcpu_notifier(&gator_cpu_notifier);
+        if (retval == 0)
+                retval = register_pm_notifier(&gator_pm_notifier);
+        return retval;
 }
 
 static void gator_notifier_stop(void)
 {
+        unregister_pm_notifier(&gator_pm_notifier);
         unregister_hotcpu_notifier(&gator_cpu_notifier);
 }