Xen support for the ondemand governor [2/2] (linux)

@@ -221,18 +222,14 @@ static struct attribute_group dbs_attr_g
 };
 
 /************************** sysfs end ************************/
-
-static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
-{
-	unsigned int idle_ticks, total_ticks;
-	unsigned int load;
+#ifndef CONFIG_XEN
+static int dbs_calc_load(struct cpu_dbs_info_s *this_dbs_info)
+{
+	struct cpufreq_policy *policy;
 	cputime64_t cur_jiffies;
-
-	struct cpufreq_policy *policy;
+	cputime64_t total_ticks, idle_ticks;
 	unsigned int j;
-
-	if (!this_dbs_info->enable)
-		return;
+	int load;
 
 	policy = this_dbs_info->cur_policy;
 	cur_jiffies = jiffies64_to_cputime64(get_jiffies_64());

@@ -240,7 +237,7 @@ static void dbs_check_cpu(struct cpu_dbs
 			this_dbs_info->prev_cpu_wall);
 	this_dbs_info->prev_cpu_wall = cur_jiffies;
 	if (!total_ticks)
-		return;
+		return 200;
 	/*
 	 * Every sampling_rate, we check, if current idle time is less
 	 * than 20% (default), then we try to increase frequency

@@ -270,6 +267,67 @@ static void dbs_check_cpu(struct cpu_dbs
 			idle_ticks = tmp_idle_ticks;
 	}
 	load = (100 * (total_ticks - idle_ticks)) / total_ticks;
+	return load;
+}
+#else
+
+#include <xen/interface/platform.h>
+static int dbs_calc_load(struct cpu_dbs_info_s *this_dbs_info)
+{
+	int load = 0;
+        struct xen_platform_op op;
+        uint64_t idletime[NR_CPUS];
+	uint64_t totaltime[NR_CPUS];
+	struct cpufreq_policy *policy;
+	unsigned int j;
+
+        op.cmd = XENPF_getidletime;
+        op.u.getidletime.max_cpus = num_online_cpus();
+        set_xen_guest_handle(op.u.getidletime.idletime, idletime);
+        set_xen_guest_handle(op.u.getidletime.totaltime, totaltime);
+        HYPERVISOR_platform_op(&op);
+
+	policy = this_dbs_info->cur_policy;
+	for_each_cpu_mask(j, policy->cpus) {
+		cputime64_t total_idle_ticks, total_wall_ticks;
+		cputime64_t tmp_idle_ticks, tmp_wall_ticks;
+		struct cpu_dbs_info_s *j_dbs_info;
+		unsigned long tmp_load;
+
+		j_dbs_info = &per_cpu(cpu_dbs_info, j);
+		total_idle_ticks = idletime[j];
+		tmp_idle_ticks = cputime64_sub(total_idle_ticks,
+				j_dbs_info->prev_cpu_idle);
+		total_wall_ticks = totaltime[j];
+		tmp_wall_ticks = cputime64_sub(total_wall_ticks,
+				j_dbs_info->prev_cpu_wall);
+		if (tmp_wall_ticks == 0)
+			return 200;
+
+		j_dbs_info->prev_cpu_wall = total_wall_ticks;
+		j_dbs_info->prev_cpu_idle = total_idle_ticks;
+
+		tmp_load = (100 * (tmp_wall_ticks - tmp_idle_ticks)) /
+				tmp_wall_ticks;
+		load = max(load, min(100, (int) tmp_load));
+	}
+	return load;
+}
+#endif
+
+static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
+{
+	int load;
+
+	struct cpufreq_policy *policy;
+
+	if (!this_dbs_info->enable)
+		return;
+
+	policy = this_dbs_info->cur_policy;
+	load = dbs_calc_load(this_dbs_info);
+	if (load > 100) 
+		return;
 
 	/* Check for frequency increase */
 	if (load > dbs_tuners_ins.up_threshold) {

diff -r 9bf1ddd0f6bf include/xen/interface/platform.h
@@ -179,6 +179,7 @@ struct xenpf_getidletime {
     /* IN variables. */
     uint32_t max_cpus;
     XEN_GUEST_HANDLE(uint64_t) idletime;
+    XEN_GUEST_HANDLE(uint64_t) totaltime;
     /* OUT variables. */
     uint32_t nr_cpus;
 };