1 files changed, 37 insertions, 40 deletions

diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
index 19f6b9d..3e3cd3d 100644
--- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -68,6 +68,7 @@ struct acpi_cpufreq_data {
 	unsigned int max_freq;
 	unsigned int resume;
 	unsigned int cpu_feature;
+	u64 saved_aperf, saved_mperf;
 };
 
 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data);
@@ -152,7 +153,8 @@ struct drv_cmd {
 	u32 val;
 };
 
-static long do_drv_read(void *_cmd)
+/* Called via smp_call_function_single(), on the target CPU */
+static void do_drv_read(void *_cmd)
 {
 	struct drv_cmd *cmd = _cmd;
 	u32 h;
@@ -169,10 +171,10 @@ static long do_drv_read(void *_cmd)
 	default:
 		break;
 	}
-	return 0;
 }
 
-static long do_drv_write(void *_cmd)
+/* Called via smp_call_function_many(), on the target CPUs */
+static void do_drv_write(void *_cmd)
 {
 	struct drv_cmd *cmd = _cmd;
 	u32 lo, hi;
@@ -191,23 +193,18 @@ static long do_drv_write(void *_cmd)
 	default:
 		break;
 	}
-	return 0;
 }
 
 static void drv_read(struct drv_cmd *cmd)
 {
 	cmd->val = 0;
 
-	work_on_cpu(cpumask_any(cmd->mask), do_drv_read, cmd);
+	smp_call_function_single(cpumask_any(cmd->mask), do_drv_read, cmd, 1);
 }
 
 static void drv_write(struct drv_cmd *cmd)
 {
-	unsigned int i;
-
-	for_each_cpu(i, cmd->mask) {
-		work_on_cpu(i, do_drv_write, cmd);
-	}
+	smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
 }
 
 static u32 get_cur_val(const struct cpumask *mask)
@@ -241,28 +238,23 @@ static u32 get_cur_val(const struct cpumask *mask)
 	return cmd.val;
 }
 
-struct perf_cur {
+struct perf_pair {
 	union {
 		struct {
 			u32 lo;
 			u32 hi;
 		} split;
 		u64 whole;
-	} aperf_cur, mperf_cur;
+	} aperf, mperf;
 };
 
-
-static long read_measured_perf_ctrs(void *_cur)
+/* Called via smp_call_function_single(), on the target CPU */
+static void read_measured_perf_ctrs(void *_cur)
 {
-	struct perf_cur *cur = _cur;
-
-	rdmsr(MSR_IA32_APERF, cur->aperf_cur.split.lo, cur->aperf_cur.split.hi);
-	rdmsr(MSR_IA32_MPERF, cur->mperf_cur.split.lo, cur->mperf_cur.split.hi);
-
-	wrmsr(MSR_IA32_APERF, 0, 0);
-	wrmsr(MSR_IA32_MPERF, 0, 0);
+	struct perf_pair *cur = _cur;
 
-	return 0;
+	rdmsr(MSR_IA32_APERF, cur->aperf.split.lo, cur->aperf.split.hi);
+	rdmsr(MSR_IA32_MPERF, cur->mperf.split.lo, cur->mperf.split.hi);
 }
 
 /*
@@ -281,52 +273,57 @@ static long read_measured_perf_ctrs(void *_cur)
 static unsigned int get_measured_perf(struct cpufreq_policy *policy,
 				      unsigned int cpu)
 {
-	struct perf_cur cur;
+	struct perf_pair readin, cur;
 	unsigned int perf_percent;
 	unsigned int retval;
 
-	if (!work_on_cpu(cpu, read_measured_perf_ctrs, &cur))
+	if (smp_call_function_single(cpu, read_measured_perf_ctrs, &cur, 1))
 		return 0;
 
+	cur.aperf.whole = readin.aperf.whole -
+				per_cpu(drv_data, cpu)->saved_aperf;
+	cur.mperf.whole = readin.mperf.whole -
+				per_cpu(drv_data, cpu)->saved_mperf;
+	per_cpu(drv_data, cpu)->saved_aperf = readin.aperf.whole;
+	per_cpu(drv_data, cpu)->saved_mperf = readin.mperf.whole;
+
 #ifdef __i386__
 	/*
 	 * We dont want to do 64 bit divide with 32 bit kernel
 	 * Get an approximate value. Return failure in case we cannot get
 	 * an approximate value.
 	 */
-	if (unlikely(cur.aperf_cur.split.hi || cur.mperf_cur.split.hi)) {
+	if (unlikely(cur.aperf.split.hi || cur.mperf.split.hi)) {
 		int shift_count;
 		u32 h;
 
-		h = max_t(u32, cur.aperf_cur.split.hi, cur.mperf_cur.split.hi);
+		h = max_t(u32, cur.aperf.split.hi, cur.mperf.split.hi);
 		shift_count = fls(h);
 
-		cur.aperf_cur.whole >>= shift_count;
-		cur.mperf_cur.whole >>= shift_count;
+		cur.aperf.whole >>= shift_count;
+		cur.mperf.whole >>= shift_count;
 	}
 
-	if (((unsigned long)(-1) / 100) < cur.aperf_cur.split.lo) {
+	if (((unsigned long)(-1) / 100) < cur.aperf.split.lo) {
 		int shift_count = 7;
-		cur.aperf_cur.split.lo >>= shift_count;
-		cur.mperf_cur.split.lo >>= shift_count;
+		cur.aperf.split.lo >>= shift_count;
+		cur.mperf.split.lo >>= shift_count;
 	}
 
-	if (cur.aperf_cur.split.lo && cur.mperf_cur.split.lo)
-		perf_percent = (cur.aperf_cur.split.lo * 100) /
-				cur.mperf_cur.split.lo;
+	if (cur.aperf.split.lo && cur.mperf.split.lo)
+		perf_percent = (cur.aperf.split.lo * 100) / cur.mperf.split.lo;
 	else
 		perf_percent = 0;
 
 #else
-	if (unlikely(((unsigned long)(-1) / 100) < cur.aperf_cur.whole)) {
+	if (unlikely(((unsigned long)(-1) / 100) < cur.aperf.whole)) {
 		int shift_count = 7;
-		cur.aperf_cur.whole >>= shift_count;
-		cur.mperf_cur.whole >>= shift_count;
+		cur.aperf.whole >>= shift_count;
+		cur.mperf.whole >>= shift_count;
 	}
 
-	if (cur.aperf_cur.whole && cur.mperf_cur.whole)
-		perf_percent = (cur.aperf_cur.whole * 100) /
-				cur.mperf_cur.whole;
+	if (cur.aperf.whole && cur.mperf.whole)
+		perf_percent = (cur.aperf.whole * 100) / cur.mperf.whole;
 	else
 		perf_percent = 0;