a few minor idle patches

a few minor idle patches

[Len Brown]

let me know if you see any troubles with them.

thanks,
Len Brown, Intel Open Source Technology Center

[PATCH 1/3] intel_idle: simplify test for leave_mm()

[Len Brown]

From: Len Brown <len.brown@intel.com>

A run-time test to invoke leave_mm() for the deepest
supported C-state is redundant, since the appropriate
C-states already have flags with CPUIDLE_FLAG_TLB_FLUSHED set.

Signed-off-by: Len Brown <len.brown@intel.com>
---
 drivers/idle/intel_idle.c |    9 +++------
 1 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index c37ef64..ad0fb01 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -186,13 +186,10 @@ static int intel_idle(struct cpuidle_device *dev, struct cpuidle_state *state)
 	local_irq_disable();
 
 	/*
-	 * If the state flag indicates that the TLB will be flushed or if this
-	 * is the deepest c-state supported, do a voluntary leave mm to avoid
-	 * costly and mostly unnecessary wakeups for flushing the user TLB's
-	 * associated with the active mm.
+	 * leave_mm() to avoid costly and often unnecessary wakeups
+	 * for flushing the user TLB's associated with the active mm.
 	 */
-	if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED ||
-	    (&dev->states[dev->state_count - 1] == state))
+	if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED)
 		leave_mm(cpu);
 
 	if (!(lapic_timer_reliable_states & (1 << (cstate))))
-- 
1.7.3.1.120.g38a18

[PATCH 2/3] intel_idle: delete bogus data from cpuidle_state.power_usage

[Len Brown]

From: Len Brown <len.brown@intel.com>

The mW data in this field is a total fabrication
and serves no purpose other than to mislead
those who might see it in sysfs.  Delete it.

Signed-off-by: Len Brown <len.brown@intel.com>
---
 drivers/idle/intel_idle.c |    7 -------
 1 files changed, 0 insertions(+), 7 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index ad0fb01..8e35c89 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -101,7 +101,6 @@ static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x00,
 		.flags = CPUIDLE_FLAG_TIME_VALID,
 		.exit_latency = 3,
-		.power_usage = 1000,
 		.target_residency = 6,
 		.enter = &intel_idle },
 	{ /* MWAIT C2 */
@@ -110,7 +109,6 @@ static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x10,
 		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
 		.exit_latency = 20,
-		.power_usage = 500,
 		.target_residency = 80,
 		.enter = &intel_idle },
 	{ /* MWAIT C3 */
@@ -119,7 +117,6 @@ static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x20,
 		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
 		.exit_latency = 200,
-		.power_usage = 350,
 		.target_residency = 800,
 		.enter = &intel_idle },
 };
@@ -132,7 +129,6 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x00,
 		.flags = CPUIDLE_FLAG_TIME_VALID,
 		.exit_latency = 1,
-		.power_usage = 1000,
 		.target_residency = 4,
 		.enter = &intel_idle },
 	{ /* MWAIT C2 */
@@ -141,7 +137,6 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x10,
 		.flags = CPUIDLE_FLAG_TIME_VALID,
 		.exit_latency = 20,
-		.power_usage = 500,
 		.target_residency = 80,
 		.enter = &intel_idle },
 	{ /* MWAIT C3 */ },
@@ -151,7 +146,6 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x30,
 		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
 		.exit_latency = 100,
-		.power_usage = 250,
 		.target_residency = 400,
 		.enter = &intel_idle },
 	{ /* MWAIT C5 */ },
@@ -161,7 +155,6 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.driver_data = (void *) 0x52,
 		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
 		.exit_latency = 140,
-		.power_usage = 150,
 		.target_residency = 560,
 		.enter = &intel_idle },
 };
-- 
1.7.3.1.120.g38a18

[PATCH 3/3] acpi_idle: delete bogus data from cpuidle_state.power_usage

[Len Brown]

From: Len Brown <len.brown@intel.com>

The mW data in this field comes from AML _CST,
which was typed in by a BIOS writer, and is thus
considered unreliable.

Linux does not use it for making any decisions.
We do display it in sysfs where somebody might
read it and assume it is meaningful, so delete it.

Signed-off-by: Len Brown <len.brown@intel.com>
---
 drivers/acpi/processor_idle.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index f4428e8..07a8bb6 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -1013,7 +1013,6 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
 		strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
 		state->exit_latency = cx->latency;
 		state->target_residency = cx->latency * latency_factor;
-		state->power_usage = cx->power;
 
 		state->flags = 0;
 		switch (cx->type) {
-- 
1.7.3.1.120.g38a18