Merge intel.com:/home/lenb/src/26-stable-dev

into intel.com:/home/lenb/src/26-latest-dev

drivers/acpi/debug.c

@@ -4,6 +4,7 @@
 
 #include <linux/proc_fs.h>
 #include <linux/init.h>
+#include <linux/kernel.h>
 #include <linux/moduleparam.h>
 #include <asm/uaccess.h>
 #include <acpi/acpi_drivers.h>
@@ -87,7 +88,6 @@ const struct acpi_dlevel acpi_debug_levels[] =
 	ACPI_DEBUG_INIT(ACPI_LV_FULL_TABLES),
 	ACPI_DEBUG_INIT(ACPI_LV_EVENTS),             
 };
-#define NUM_OF(v)	( sizeof(v)/sizeof(v[0]) )
 
 static int
 acpi_system_read_debug (
@@ -100,7 +100,7 @@ acpi_system_read_debug (
 {
 	char			*p = page;
 	int 			size = 0;
-	int			i;
+	unsigned int		i;
 
 	if (off != 0)
 		goto end;
@@ -109,7 +109,7 @@ acpi_system_read_debug (
 
 	switch ((unsigned long) data) {
 	case 0:
-		for (i = 0; i < NUM_OF(acpi_debug_layers); i++) {
+		for (i = 0; i < ARRAY_SIZE(acpi_debug_layers); i++) {
 			p += sprintf(p, "%-25s\t0x%08lX [%c]\n",
 				acpi_debug_layers[i].name,
 				acpi_debug_layers[i].value,
@@ -126,7 +126,7 @@ acpi_system_read_debug (
 			acpi_dbg_layer);
 		break;
 	case 1:
-		for (i = 0; i < NUM_OF(acpi_debug_levels); i++) {
+		for (i = 0; i < ARRAY_SIZE(acpi_debug_levels); i++) {
 			p += sprintf(p, "%-25s\t0x%08lX [%c]\n",
 				acpi_debug_levels[i].name,
 				acpi_debug_levels[i].value,

drivers/acpi/processor_idle.c

@@ -60,6 +60,15 @@ module_param(max_cstate, uint, 0644);
 static unsigned int nocst = 0;
 module_param(nocst, uint, 0000);
 
+/*
+ * bm_history -- bit-mask with a bit per jiffy of bus-master activity
+ * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms
+ * 800 HZ: 0xFFFFFFFF: 32 jiffies = 40ms
+ * 100 HZ: 0x0000000F: 4 jiffies = 40ms
+ * reduce history for more aggressive entry into C3
+ */
+static unsigned int bm_history = (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1));
+module_param(bm_history, uint, 0644);
 /* --------------------------------------------------------------------------
                                 Power Management
    -------------------------------------------------------------------------- */
@@ -193,8 +202,18 @@ static void acpi_processor_idle (void)
 	 */
 	if (pr->flags.bm_check) {
 		u32		bm_status = 0;
+		unsigned long	diff = jiffies - pr->power.bm_check_timestamp;
+
+		if (diff > 32)
+			diff = 32;
 
-		pr->power.bm_activity <<= 1;
+		while (diff) {
+			/* if we didn't get called, assume there was busmaster activity */
+			diff--;
+			if (diff)
+				pr->power.bm_activity |= 0x1;
+			pr->power.bm_activity <<= 1;
+		}
 
 		acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS,
 			&bm_status, ACPI_MTX_DO_NOT_LOCK);
@@ -213,6 +232,9 @@ static void acpi_processor_idle (void)
 				|| (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
 				pr->power.bm_activity++;
 		}
+
+		pr->power.bm_check_timestamp = jiffies;
+
 		/*
 		 * Apply bus mastering demotion policy.  Automatically demote
 		 * to avoid a faulty transition.  Note that the processor
@@ -425,7 +447,7 @@ acpi_processor_set_power_policy (
 			cx->demotion.threshold.ticks = cx->latency_ticks;
 			cx->demotion.threshold.count = 1;
 			if (cx->type == ACPI_STATE_C3)
-				cx->demotion.threshold.bm = 0x0F;
+				cx->demotion.threshold.bm = bm_history;
 		}
 
 		lower = cx;
@@ -445,7 +467,7 @@ acpi_processor_set_power_policy (
 			else
 				cx->promotion.threshold.count = 10;
 			if (higher->type == ACPI_STATE_C3)
-				cx->promotion.threshold.bm = 0x0F;
+				cx->promotion.threshold.bm = bm_history;
 		}
 
 		higher = cx;

include/acpi/processor.h

@@ -54,6 +54,7 @@ struct acpi_processor_cx {
 
 struct acpi_processor_power {
 	struct acpi_processor_cx *state;
+	unsigned long		bm_check_timestamp;
 	u32			default_state;
 	u32			bm_activity;
 	int			count;