[PATCH 0/9] cpuidle: rework device state count handling

[PATCH 0/9] cpuidle: rework device state count handling

[Bartlomiej Zolnierkiewicz]

Hi,

Some cpuidle drivers assume that cpuidle core will handle cases where
device->state_count is smaller than driver->state_count, unfortunately
currently this is untrue (device->state_count is used only for handling
cpuidle state sysfs entries and driver->state_count is used for all
other cases) and will not be fixed in the future as device->state_count
is planned to be removed [1].

This patchset fixes such drivers (ARM EXYNOS cpuidle driver and ACPI
cpuidle driver), removes superflous device->state_count initialization
from drivers for which device->state_count equals driver->state_count
(POWERPC pseries cpuidle driver and intel_idle driver) and finally
removes state_count field from struct cpuidle_device.

Additionaly (while at it) this patchset fixes C1E promotion disable
quirk handling (in intel_idle driver) and converts cpuidle drivers code
to use the common cpuidle_[un]register() routines (in POWERPC pseries
cpuidle driver and intel_idle driver).

[1] http://permalink.gmane.org/gmane.linux.power-management.general/36908

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics


Bartlomiej Zolnierkiewicz (9):
  ARM: EXYNOS: cpuidle: fix AFTR mode check
  POWERPC: pseries: cpuidle: remove superfluous dev->state_count
    initialization
  POWERPC: pseries: cpuidle: use the common cpuidle_[un]register()
    routines
  ACPI / cpuidle: fix max idle state handling with hotplug CPU support
  ACPI / cpuidle: remove dev->state_count setting
  intel_idle: do C1E promotion disable quirk for hotplugged CPUs
  intel_idle: remove superfluous dev->state_count initialization
  intel_idle: use the common cpuidle_[un]register() routines
  cpuidle: remove state_count field from struct cpuidle_device

 arch/arm/mach-exynos/cpuidle.c                  |   8 +-
 arch/powerpc/platforms/pseries/processor_idle.c |  59 +---------
 drivers/acpi/processor_idle.c                   |  29 +++--
 drivers/cpuidle/cpuidle.c                       |   3 -
 drivers/cpuidle/sysfs.c                         |   5 +-
 drivers/idle/intel_idle.c                       | 140 +++++-------------------
 include/linux/cpuidle.h                         |   1 -
 7 files changed, 51 insertions(+), 194 deletions(-)

-- 
1.8.2.3

[PATCH 1/9] ARM: EXYNOS: cpuidle: fix AFTR mode check

[Bartlomiej Zolnierkiewicz]

The EXYNOS cpuidle driver code assumes that cpuidle core will handle
dev->state_count smaller than drv->state_count but currently this is
untrue (dev->state_count is used only for handling cpuidle state sysfs
entries and drv->state_count is used for all other cases) and will not
be fixed in the future as dev->state_count is planned to be removed.

Fix the issue by checking for the max supported idle state in AFTR
state's ->enter handler (exynos4_enter_lowpower()) and entering AFTR
mode only when cores other than CPU0 are offline.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
---
 arch/arm/mach-exynos/cpuidle.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index 225ee84..bb8c4e0 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -150,8 +150,8 @@ static int exynos4_enter_lowpower(struct cpuidle_device *dev,
 {
 	int new_index = index;
 
-	/* This mode only can be entered when other core's are offline */
-	if (num_online_cpus() > 1)
+	/* AFTR can only be entered when cores other than CPU0 are offline */
+	if (num_online_cpus() > 1 || dev->cpu != 0)
 		new_index = drv->safe_state_index;
 
 	if (new_index == 0)
@@ -210,10 +210,6 @@ static int __init exynos4_init_cpuidle(void)
 		device = &per_cpu(exynos4_cpuidle_device, cpu_id);
 		device->cpu = cpu_id;
 
-		/* Support IDLE only */
-		if (cpu_id != 0)
-			device->state_count = 1;
-
 		ret = cpuidle_register_device(device);
 		if (ret) {
 			printk(KERN_ERR "CPUidle register device failed\n");
-- 
1.8.2.3

[PATCH 2/9] POWERPC: pseries: cpuidle: remove superfluous dev->state_count initialization

[Bartlomiej Zolnierkiewicz]

pseries cpuidle driver sets dev->state_count to drv->state_count so
the default dev->state_count initialization in cpuidle_enable_device()
(called from cpuidle_register_device()) can be used instead.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/pseries/processor_idle.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
index 14899b1..23fc091 100644
--- a/arch/powerpc/platforms/pseries/processor_idle.c
+++ b/arch/powerpc/platforms/pseries/processor_idle.c
@@ -273,7 +273,6 @@ static void pseries_idle_devices_uninit(void)
 static int pseries_idle_devices_init(void)
 {
 	int i;
-	struct cpuidle_driver *drv = &pseries_idle_driver;
 	struct cpuidle_device *dev;
 
 	pseries_cpuidle_devices = alloc_percpu(struct cpuidle_device);
@@ -282,7 +281,6 @@ static int pseries_idle_devices_init(void)
 
 	for_each_possible_cpu(i) {
 		dev = per_cpu_ptr(pseries_cpuidle_devices, i);
-		dev->state_count = drv->state_count;
 		dev->cpu = i;
 		if (cpuidle_register_device(dev)) {
 			printk(KERN_DEBUG \
-- 
1.8.2.3

[PATCH 3/9] POWERPC: pseries: cpuidle: use the common cpuidle_[un]register() routines

[Bartlomiej Zolnierkiewicz]

It is now possible to use the common cpuidle_[un]register() routines
(instead of open-coding them) so do it.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/pseries/processor_idle.c | 57 ++-----------------------
 1 file changed, 3 insertions(+), 54 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
index 23fc091..e4c1516 100644
--- a/arch/powerpc/platforms/pseries/processor_idle.c
+++ b/arch/powerpc/platforms/pseries/processor_idle.c
@@ -30,7 +30,6 @@ struct cpuidle_driver pseries_idle_driver = {
 #define MAX_IDLE_STATE_COUNT	2
 
 static int max_idle_state = MAX_IDLE_STATE_COUNT - 1;
-static struct cpuidle_device __percpu *pseries_cpuidle_devices;
 static struct cpuidle_state *cpuidle_state_table;
 
 static inline void idle_loop_prolog(unsigned long *in_purr)
@@ -193,7 +192,7 @@ static int pseries_cpuidle_add_cpu_notifier(struct notifier_block *n,
 {
 	int hotcpu = (unsigned long)hcpu;
 	struct cpuidle_device *dev =
-			per_cpu_ptr(pseries_cpuidle_devices, hotcpu);
+			per_cpu_ptr(cpuidle_devices, hotcpu);
 
 	if (dev && cpuidle_get_driver()) {
 		switch (action) {
@@ -250,48 +249,6 @@ static int pseries_cpuidle_driver_init(void)
 	return 0;
 }
 
-/* pseries_idle_devices_uninit(void)
- * unregister cpuidle devices and de-allocate memory
- */
-static void pseries_idle_devices_uninit(void)
-{
-	int i;
-	struct cpuidle_device *dev;
-
-	for_each_possible_cpu(i) {
-		dev = per_cpu_ptr(pseries_cpuidle_devices, i);
-		cpuidle_unregister_device(dev);
-	}
-
-	free_percpu(pseries_cpuidle_devices);
-	return;
-}
-
-/* pseries_idle_devices_init()
- * allocate, initialize and register cpuidle device
- */
-static int pseries_idle_devices_init(void)
-{
-	int i;
-	struct cpuidle_device *dev;
-
-	pseries_cpuidle_devices = alloc_percpu(struct cpuidle_device);
-	if (pseries_cpuidle_devices == NULL)
-		return -ENOMEM;
-
-	for_each_possible_cpu(i) {
-		dev = per_cpu_ptr(pseries_cpuidle_devices, i);
-		dev->cpu = i;
-		if (cpuidle_register_device(dev)) {
-			printk(KERN_DEBUG \
-				"cpuidle_register_device %d failed!\n", i);
-			return -EIO;
-		}
-	}
-
-	return 0;
-}
-
 /*
  * pseries_idle_probe()
  * Choose state table for shared versus dedicated partition
@@ -327,19 +284,12 @@ static int __init pseries_processor_idle_init(void)
 		return retval;
 
 	pseries_cpuidle_driver_init();
-	retval = cpuidle_register_driver(&pseries_idle_driver);
+	retval = cpuidle_register(&pseries_idle_driver, NULL);
 	if (retval) {
 		printk(KERN_DEBUG "Registration of pseries driver failed.\n");
 		return retval;
 	}
 
-	retval = pseries_idle_devices_init();
-	if (retval) {
-		pseries_idle_devices_uninit();
-		cpuidle_unregister_driver(&pseries_idle_driver);
-		return retval;
-	}
-
 	register_cpu_notifier(&setup_hotplug_notifier);
 	printk(KERN_DEBUG "pseries_idle_driver registered\n");
 
@@ -350,8 +300,7 @@ static void __exit pseries_processor_idle_exit(void)
 {
 
 	unregister_cpu_notifier(&setup_hotplug_notifier);
-	pseries_idle_devices_uninit();
-	cpuidle_unregister_driver(&pseries_idle_driver);
+	cpuidle_unregister(&pseries_idle_driver);
 
 	return;
 }
-- 
1.8.2.3

[PATCH 4/9] ACPI / cpuidle: fix max idle state handling with hotplug CPU support

[Bartlomiej Zolnierkiewicz]

acpi_processor_hotplug() calls acpi_processor_setup_cpuidle_cx()
without calling acpi_processor_setup_cpuidle_states() first so it
is possible that dev->state_count becomes different from
drv->state_count (in case of SMP system with unsupported C2/C3
states + enabled CPU hotplug and num_online_cpus() becoming > 1).

The driver code assumes that cpuidle core will handle such cases
but currently this is untrue (dev->state_count is used only for
handling cpuidle state sysfs entries and drv->state_count is used
for all other cases) and will not be fixed in the future as
dev->state_count is planned to be removed.

Fix the issue by checking for the max supported idle state in
C2/C3 state's ->enter handler (acpi_idle_enter_simple() for C2/C3
and acpi_idle_enter_bm() for C3 + bm_check flag set) and setting
the C1 state (instead of higher states) when needed.

Also remove no longer needed max idle state checks from
acpi_processor_setup_cpuidle_[states,cx]().

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Len Brown <lenb@kernel.org>
---
 drivers/acpi/processor_idle.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index f98dd00..853fe86 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -790,6 +790,13 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
 	if (unlikely(!pr))
 		return -EINVAL;
 
+#ifdef CONFIG_HOTPLUG_CPU
+	if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+	    !pr->flags.has_cst &&
+	    !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
+		return acpi_idle_enter_c1(dev, drv, CPUIDLE_DRIVER_STATE_START);
+#endif
+
 	if (cx->entry_method != ACPI_CSTATE_FFH) {
 		current_thread_info()->status &= ~TS_POLLING;
 		/*
@@ -848,6 +855,13 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
 	if (unlikely(!pr))
 		return -EINVAL;
 
+#ifdef CONFIG_HOTPLUG_CPU
+	if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+	    !pr->flags.has_cst &&
+	    !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
+		return acpi_idle_enter_c1(dev, drv, CPUIDLE_DRIVER_STATE_START);
+#endif
+
 	if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
 		if (drv->safe_state_index >= 0) {
 			return drv->states[drv->safe_state_index].enter(dev,
@@ -961,12 +975,6 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 		if (!cx->valid)
 			continue;
 
-#ifdef CONFIG_HOTPLUG_CPU
-		if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
-		    !pr->flags.has_cst &&
-		    !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
-			continue;
-#endif
 		per_cpu(acpi_cstate[count], dev->cpu) = cx;
 
 		count++;
@@ -1016,13 +1024,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
 		if (!cx->valid)
 			continue;
 
-#ifdef CONFIG_HOTPLUG_CPU
-		if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
-		    !pr->flags.has_cst &&
-		    !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
-			continue;
-#endif
-
 		state = &drv->states[count];
 		snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
 		strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
-- 
1.8.2.3

[PATCH 5/9] ACPI / cpuidle: remove dev->state_count setting

[Bartlomiej Zolnierkiewicz]

dev->state_count is now always equal to drv->state_count and
drv->state_count no longer can change during driver's lifetime so
the default dev->state_count initialization in cpuidle_enable_device()
(called from cpuidle_register_device()) can be used instead.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Len Brown <lenb@kernel.org>
---
 drivers/acpi/processor_idle.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 853fe86..4b6d20a 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -982,8 +982,6 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 			break;
 	}
 
-	dev->state_count = count;
-
 	if (!count)
 		return -EINVAL;
 
-- 
1.8.2.3

[PATCH 6/9] intel_idle: do C1E promotion disable quirk for hotplugged CPUs

[Bartlomiej Zolnierkiewicz]

If the system is booted with some CPUs offline C1E promotion disable quirk
won't be applied because on_each_cpu() in intel_idle_cpuidle_driver_init()
operates only on online CPUs. Fix it by adding the C1E promotion disable
handling to intel_idle_cpu_init() (which is also called during CPU_ONLINE
operation).

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Len Brown <lenb@kernel.org>
---
 drivers/idle/intel_idle.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index fa6964d..3d0e11f 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -661,6 +661,9 @@ static int intel_idle_cpu_init(int cpu)
 	if (icpu->auto_demotion_disable_flags)
 		smp_call_function_single(cpu, auto_demotion_disable, NULL, 1);
 
+	if (icpu->disable_promotion_to_c1e)
+		smp_call_function_single(cpu, c1e_promotion_disable, NULL, 1);
+
 	return 0;
 }
 
-- 
1.8.2.3

[PATCH 7/9] intel_idle: remove superfluous dev->state_count initialization

[Bartlomiej Zolnierkiewicz]

intel_idle driver sets dev->state_count to drv->state_count so
the default dev->state_count initialization in cpuidle_enable_device()
(called from cpuidle_register_device()) can be used instead.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Len Brown <lenb@kernel.org>
---
 drivers/idle/intel_idle.c | 29 -----------------------------
 1 file changed, 29 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 3d0e11f..012a28a 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -617,39 +617,10 @@ static int intel_idle_cpuidle_driver_init(void)
  */
 static int intel_idle_cpu_init(int cpu)
 {
-	int cstate;
 	struct cpuidle_device *dev;
 
 	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
 
-	dev->state_count = 1;
-
-	for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
-		int num_substates, mwait_hint, mwait_cstate, mwait_substate;
-
-		if (cpuidle_state_table[cstate].enter == NULL)
-			continue;
-
-		if (cstate + 1 > max_cstate) {
-			printk(PREFIX "max_cstate %d reached\n", max_cstate);
-			break;
-		}
-
-		mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
-		mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint);
-		mwait_substate = MWAIT_HINT2SUBSTATE(mwait_hint);
-
-		/* does the state exist in CPUID.MWAIT? */
-		num_substates = (mwait_substates >> ((mwait_cstate + 1) * 4))
-					& MWAIT_SUBSTATE_MASK;
-
-		/* if sub-state in table is not enumerated by CPUID */
-		if ((mwait_substate + 1) > num_substates)
-			continue;
-
-		dev->state_count += 1;
-	}
-
 	dev->cpu = cpu;
 
 	if (cpuidle_register_device(dev)) {
-- 
1.8.2.3

[PATCH 8/9] intel_idle: use the common cpuidle_[un]register() routines

[Bartlomiej Zolnierkiewicz]

It is now possible to use the common cpuidle_[un]register() routines
(instead of open-coding them) so do it.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Len Brown <lenb@kernel.org>
---
 drivers/idle/intel_idle.c | 114 ++++++++++++----------------------------------
 1 file changed, 29 insertions(+), 85 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 012a28a..4bfc6fc 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -93,10 +93,8 @@ struct idle_cpu {
 };
 
 static const struct idle_cpu *icpu;
-static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
 static int intel_idle(struct cpuidle_device *dev,
 			struct cpuidle_driver *drv, int index);
-static int intel_idle_cpu_init(int cpu);
 
 static struct cpuidle_state *cpuidle_state_table;
 
@@ -384,11 +382,27 @@ static void __setup_broadcast_timer(void *arg)
 	clockevents_notify(reason, &cpu);
 }
 
+static void auto_demotion_disable(void *dummy)
+{
+	unsigned long long msr_bits;
+
+	rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
+	msr_bits &= ~(icpu->auto_demotion_disable_flags);
+	wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
+}
+static void c1e_promotion_disable(void *dummy)
+{
+	unsigned long long msr_bits;
+
+	rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
+	msr_bits &= ~0x2;
+	wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
+}
+
 static int cpu_hotplug_notify(struct notifier_block *n,
 			      unsigned long action, void *hcpu)
 {
 	int hotcpu = (unsigned long)hcpu;
-	struct cpuidle_device *dev;
 
 	switch (action & 0xf) {
 	case CPU_ONLINE:
@@ -400,11 +414,15 @@ static int cpu_hotplug_notify(struct notifier_block *n,
 		/*
 		 * Some systems can hotplug a cpu at runtime after
 		 * the kernel has booted, we have to initialize the
-		 * driver in this case
+		 * hardware in this case.
 		 */
-		dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu);
-		if (!dev->registered)
-			intel_idle_cpu_init(hotcpu);
+		if (icpu->auto_demotion_disable_flags)
+			smp_call_function_single(hotcpu, auto_demotion_disable,
+						NULL, 1);
+
+		if (icpu->disable_promotion_to_c1e)
+			smp_call_function_single(hotcpu, c1e_promotion_disable,
+						NULL, 1);
 
 		break;
 	}
@@ -415,23 +433,6 @@ static struct notifier_block cpu_hotplug_notifier = {
 	.notifier_call = cpu_hotplug_notify,
 };
 
-static void auto_demotion_disable(void *dummy)
-{
-	unsigned long long msr_bits;
-
-	rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
-	msr_bits &= ~(icpu->auto_demotion_disable_flags);
-	wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
-}
-static void c1e_promotion_disable(void *dummy)
-{
-	unsigned long long msr_bits;
-
-	rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
-	msr_bits &= ~0x2;
-	wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
-}
-
 static const struct idle_cpu idle_cpu_nehalem = {
 	.state_table = nehalem_cstates,
 	.auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
@@ -538,23 +539,6 @@ static int intel_idle_probe(void)
 }
 
 /*
- * intel_idle_cpuidle_devices_uninit()
- * unregister, free cpuidle_devices
- */
-static void intel_idle_cpuidle_devices_uninit(void)
-{
-	int i;
-	struct cpuidle_device *dev;
-
-	for_each_online_cpu(i) {
-		dev = per_cpu_ptr(intel_idle_cpuidle_devices, i);
-		cpuidle_unregister_device(dev);
-	}
-
-	free_percpu(intel_idle_cpuidle_devices);
-	return;
-}
-/*
  * intel_idle_cpuidle_driver_init()
  * allocate, initialize cpuidle_states
  */
@@ -610,37 +594,9 @@ static int intel_idle_cpuidle_driver_init(void)
 }
 
 
-/*
- * intel_idle_cpu_init()
- * allocate, initialize, register cpuidle_devices
- * @cpu: cpu/core to initialize
- */
-static int intel_idle_cpu_init(int cpu)
-{
-	struct cpuidle_device *dev;
-
-	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
-
-	dev->cpu = cpu;
-
-	if (cpuidle_register_device(dev)) {
-		pr_debug(PREFIX "cpuidle_register_device %d failed!\n", cpu);
-		intel_idle_cpuidle_devices_uninit();
-		return -EIO;
-	}
-
-	if (icpu->auto_demotion_disable_flags)
-		smp_call_function_single(cpu, auto_demotion_disable, NULL, 1);
-
-	if (icpu->disable_promotion_to_c1e)
-		smp_call_function_single(cpu, c1e_promotion_disable, NULL, 1);
-
-	return 0;
-}
-
 static int __init intel_idle_init(void)
 {
-	int retval, i;
+	int retval;
 
 	/* Do not load intel_idle at all for now if idle= is passed */
 	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
@@ -651,7 +607,8 @@ static int __init intel_idle_init(void)
 		return retval;
 
 	intel_idle_cpuidle_driver_init();
-	retval = cpuidle_register_driver(&intel_idle_driver);
+
+	retval = cpuidle_register(&intel_idle_driver, NULL);
 	if (retval) {
 		struct cpuidle_driver *drv = cpuidle_get_driver();
 		printk(KERN_DEBUG PREFIX "intel_idle yielding to %s",
@@ -659,17 +616,6 @@ static int __init intel_idle_init(void)
 		return retval;
 	}
 
-	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
-	if (intel_idle_cpuidle_devices == NULL)
-		return -ENOMEM;
-
-	for_each_online_cpu(i) {
-		retval = intel_idle_cpu_init(i);
-		if (retval) {
-			cpuidle_unregister_driver(&intel_idle_driver);
-			return retval;
-		}
-	}
 	register_cpu_notifier(&cpu_hotplug_notifier);
 
 	return 0;
@@ -677,9 +623,7 @@ static int __init intel_idle_init(void)
 
 static void __exit intel_idle_exit(void)
 {
-	intel_idle_cpuidle_devices_uninit();
-	cpuidle_unregister_driver(&intel_idle_driver);
-
+	cpuidle_unregister(&intel_idle_driver);
 
 	if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
 		on_each_cpu(__setup_broadcast_timer, (void *)false, 1);
-- 
1.8.2.3

[PATCH 9/9] cpuidle: remove state_count field from struct cpuidle_device

[Bartlomiej Zolnierkiewicz]

dev->state_count is now always equal to drv->state_count so
it can be removed.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/cpuidle/cpuidle.c | 3 ---
 drivers/cpuidle/sysfs.c   | 5 +++--
 include/linux/cpuidle.h   | 1 -
 3 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index d75040d..60947ca 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -293,9 +293,6 @@ int cpuidle_enable_device(struct cpuidle_device *dev)
 	if (!dev->registered)
 		return -EINVAL;
 
-	if (!dev->state_count)
-		dev->state_count = drv->state_count;
-
 	poll_idle_init(drv);
 
 	ret = cpuidle_add_device_sysfs(dev);
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
index 8739cc0..5af3fa9 100644
--- a/drivers/cpuidle/sysfs.c
+++ b/drivers/cpuidle/sysfs.c
@@ -397,7 +397,7 @@ static int cpuidle_add_state_sysfs(struct cpuidle_device *device)
 	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device);
 
 	/* state statistics */
-	for (i = 0; i < device->state_count; i++) {
+	for (i = 0; i < drv->state_count; i++) {
 		kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
 		if (!kobj)
 			goto error_state;
@@ -429,9 +429,10 @@ error_state:
  */
 static void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
 {
+	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device);
 	int i;
 
-	for (i = 0; i < device->state_count; i++)
+	for (i = 0; i < drv->state_count; i++)
 		cpuidle_free_state_kobj(device, i);
 }
 
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index 781addc..ecf7b09 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -69,7 +69,6 @@ struct cpuidle_device {
 	unsigned int		cpu;
 
 	int			last_residency;
-	int			state_count;
 	struct cpuidle_state_usage	states_usage[CPUIDLE_STATE_MAX];
 	struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
 	struct cpuidle_driver_kobj *kobj_driver;
-- 
1.8.2.3

Re: [PATCH 0/9] cpuidle: rework device state count handling

[Bartlomiej Zolnierkiewicz]

Hi Daniel,

Did you have a chance to take a look at this patchset?

Could it be queued for 3.13 (unfortunately it is probably too late for 3.12)?

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

On Tuesday, August 20, 2013 04:23:38 PM Bartlomiej Zolnierkiewicz wrote:
> Hi,
> 
> Some cpuidle drivers assume that cpuidle core will handle cases where
> device->state_count is smaller than driver->state_count, unfortunately
> currently this is untrue (device->state_count is used only for handling
> cpuidle state sysfs entries and driver->state_count is used for all
> other cases) and will not be fixed in the future as device->state_count
> is planned to be removed [1].
> 
> This patchset fixes such drivers (ARM EXYNOS cpuidle driver and ACPI
> cpuidle driver), removes superflous device->state_count initialization
> from drivers for which device->state_count equals driver->state_count
> (POWERPC pseries cpuidle driver and intel_idle driver) and finally
> removes state_count field from struct cpuidle_device.
> 
> Additionaly (while at it) this patchset fixes C1E promotion disable
> quirk handling (in intel_idle driver) and converts cpuidle drivers code
> to use the common cpuidle_[un]register() routines (in POWERPC pseries
> cpuidle driver and intel_idle driver).
> 
> [1] http://permalink.gmane.org/gmane.linux.power-management.general/36908
> 
> Best regards,
> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics
> 
> 
> Bartlomiej Zolnierkiewicz (9):
>   ARM: EXYNOS: cpuidle: fix AFTR mode check
>   POWERPC: pseries: cpuidle: remove superfluous dev->state_count
>     initialization
>   POWERPC: pseries: cpuidle: use the common cpuidle_[un]register()
>     routines
>   ACPI / cpuidle: fix max idle state handling with hotplug CPU support
>   ACPI / cpuidle: remove dev->state_count setting
>   intel_idle: do C1E promotion disable quirk for hotplugged CPUs
>   intel_idle: remove superfluous dev->state_count initialization
>   intel_idle: use the common cpuidle_[un]register() routines
>   cpuidle: remove state_count field from struct cpuidle_device
> 
>  arch/arm/mach-exynos/cpuidle.c                  |   8 +-
>  arch/powerpc/platforms/pseries/processor_idle.c |  59 +---------
>  drivers/acpi/processor_idle.c                   |  29 +++--
>  drivers/cpuidle/cpuidle.c                       |   3 -
>  drivers/cpuidle/sysfs.c                         |   5 +-
>  drivers/idle/intel_idle.c                       | 140 +++++-------------------
>  include/linux/cpuidle.h                         |   1 -
>  7 files changed, 51 insertions(+), 194 deletions(-)

Re: [PATCH 0/9] cpuidle: rework device state count handling

[Daniel Lezcano]

On 09/23/2013 06:05 PM, Bartlomiej Zolnierkiewicz wrote:
>
> Hi Daniel,
>
> Did you have a chance to take a look at this patchset?
>
> Could it be queued for 3.13 (unfortunately it is probably too late for 3.12)?

Thanks for the head up, I will review it.

Unfortunately this patchset did not get any acked-by from the different 
maintainers. Furthermore I believe it would be up to Rafael to take them.

   -- Daniel

> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics
>
> On Tuesday, August 20, 2013 04:23:38 PM Bartlomiej Zolnierkiewicz wrote:
>> Hi,
>>
>> Some cpuidle drivers assume that cpuidle core will handle cases where
>> device->state_count is smaller than driver->state_count, unfortunately
>> currently this is untrue (device->state_count is used only for handling
>> cpuidle state sysfs entries and driver->state_count is used for all
>> other cases) and will not be fixed in the future as device->state_count
>> is planned to be removed [1].
>>
>> This patchset fixes such drivers (ARM EXYNOS cpuidle driver and ACPI
>> cpuidle driver), removes superflous device->state_count initialization
>> from drivers for which device->state_count equals driver->state_count
>> (POWERPC pseries cpuidle driver and intel_idle driver) and finally
>> removes state_count field from struct cpuidle_device.
>>
>> Additionaly (while at it) this patchset fixes C1E promotion disable
>> quirk handling (in intel_idle driver) and converts cpuidle drivers code
>> to use the common cpuidle_[un]register() routines (in POWERPC pseries
>> cpuidle driver and intel_idle driver).
>>
>> [1] http://permalink.gmane.org/gmane.linux.power-management.general/36908
>>
>> Best regards,
>> --
>> Bartlomiej Zolnierkiewicz
>> Samsung R&D Institute Poland
>> Samsung Electronics
>>
>>
>> Bartlomiej Zolnierkiewicz (9):
>>    ARM: EXYNOS: cpuidle: fix AFTR mode check
>>    POWERPC: pseries: cpuidle: remove superfluous dev->state_count
>>      initialization
>>    POWERPC: pseries: cpuidle: use the common cpuidle_[un]register()
>>      routines
>>    ACPI / cpuidle: fix max idle state handling with hotplug CPU support
>>    ACPI / cpuidle: remove dev->state_count setting
>>    intel_idle: do C1E promotion disable quirk for hotplugged CPUs
>>    intel_idle: remove superfluous dev->state_count initialization
>>    intel_idle: use the common cpuidle_[un]register() routines
>>    cpuidle: remove state_count field from struct cpuidle_device
>>
>>   arch/arm/mach-exynos/cpuidle.c                  |   8 +-
>>   arch/powerpc/platforms/pseries/processor_idle.c |  59 +---------
>>   drivers/acpi/processor_idle.c                   |  29 +++--
>>   drivers/cpuidle/cpuidle.c                       |   3 -
>>   drivers/cpuidle/sysfs.c                         |   5 +-
>>   drivers/idle/intel_idle.c                       | 140 +++++-------------------
>>   include/linux/cpuidle.h                         |   1 -
>>   7 files changed, 51 insertions(+), 194 deletions(-)
>


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Re: [PATCH 1/9] ARM: EXYNOS: cpuidle: fix AFTR mode check

[Daniel Lezcano]

On 08/20/2013 04:23 PM, Bartlomiej Zolnierkiewicz wrote:
> The EXYNOS cpuidle driver code assumes that cpuidle core will handle
> dev->state_count smaller than drv->state_count but currently this is
> untrue (dev->state_count is used only for handling cpuidle state sysfs
> entries and drv->state_count is used for all other cases) and will not
> be fixed in the future as dev->state_count is planned to be removed.
>
> Fix the issue by checking for the max supported idle state in AFTR
> state's ->enter handler (exynos4_enter_lowpower()) and entering AFTR
> mode only when cores other than CPU0 are offline.
>
> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Kukjin Kim <kgene.kim@samsung.com>

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---
>   arch/arm/mach-exynos/cpuidle.c | 8 ++------
>   1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
> index 225ee84..bb8c4e0 100644
> --- a/arch/arm/mach-exynos/cpuidle.c
> +++ b/arch/arm/mach-exynos/cpuidle.c
> @@ -150,8 +150,8 @@ static int exynos4_enter_lowpower(struct cpuidle_device *dev,
>   {
>   	int new_index = index;
>
> -	/* This mode only can be entered when other core's are offline */
> -	if (num_online_cpus() > 1)
> +	/* AFTR can only be entered when cores other than CPU0 are offline */
> +	if (num_online_cpus() > 1 || dev->cpu != 0)
>   		new_index = drv->safe_state_index;
>
>   	if (new_index == 0)
> @@ -210,10 +210,6 @@ static int __init exynos4_init_cpuidle(void)
>   		device = &per_cpu(exynos4_cpuidle_device, cpu_id);
>   		device->cpu = cpu_id;
>
> -		/* Support IDLE only */
> -		if (cpu_id != 0)
> -			device->state_count = 1;
> -
>   		ret = cpuidle_register_device(device);
>   		if (ret) {
>   			printk(KERN_ERR "CPUidle register device failed\n");
>


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Re: [PATCH 2/9] POWERPC: pseries: cpuidle: remove superfluous dev->state_count initialization

[Daniel Lezcano]

On 08/20/2013 04:23 PM, Bartlomiej Zolnierkiewicz wrote:
> pseries cpuidle driver sets dev->state_count to drv->state_count so
> the default dev->state_count initialization in cpuidle_enable_device()
> (called from cpuidle_register_device()) can be used instead.
>
> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---
>   arch/powerpc/platforms/pseries/processor_idle.c | 2 --
>   1 file changed, 2 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
> index 14899b1..23fc091 100644
> --- a/arch/powerpc/platforms/pseries/processor_idle.c
> +++ b/arch/powerpc/platforms/pseries/processor_idle.c
> @@ -273,7 +273,6 @@ static void pseries_idle_devices_uninit(void)
>   static int pseries_idle_devices_init(void)
>   {
>   	int i;
> -	struct cpuidle_driver *drv = &pseries_idle_driver;
>   	struct cpuidle_device *dev;
>
>   	pseries_cpuidle_devices = alloc_percpu(struct cpuidle_device);
> @@ -282,7 +281,6 @@ static int pseries_idle_devices_init(void)
>
>   	for_each_possible_cpu(i) {
>   		dev = per_cpu_ptr(pseries_cpuidle_devices, i);
> -		dev->state_count = drv->state_count;
>   		dev->cpu = i;
>   		if (cpuidle_register_device(dev)) {
>   			printk(KERN_DEBUG \
>


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Re: [PATCH 3/9] POWERPC: pseries: cpuidle: use the common cpuidle_[un]register() routines

[Daniel Lezcano]

On 08/20/2013 04:23 PM, Bartlomiej Zolnierkiewicz wrote:
> It is now possible to use the common cpuidle_[un]register() routines
> (instead of open-coding them) so do it.
>
> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---
>   arch/powerpc/platforms/pseries/processor_idle.c | 57 ++-----------------------
>   1 file changed, 3 insertions(+), 54 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
> index 23fc091..e4c1516 100644
> --- a/arch/powerpc/platforms/pseries/processor_idle.c
> +++ b/arch/powerpc/platforms/pseries/processor_idle.c
> @@ -30,7 +30,6 @@ struct cpuidle_driver pseries_idle_driver = {
>   #define MAX_IDLE_STATE_COUNT	2
>
>   static int max_idle_state = MAX_IDLE_STATE_COUNT - 1;
> -static struct cpuidle_device __percpu *pseries_cpuidle_devices;
>   static struct cpuidle_state *cpuidle_state_table;
>
>   static inline void idle_loop_prolog(unsigned long *in_purr)
> @@ -193,7 +192,7 @@ static int pseries_cpuidle_add_cpu_notifier(struct notifier_block *n,
>   {
>   	int hotcpu = (unsigned long)hcpu;
>   	struct cpuidle_device *dev =
> -			per_cpu_ptr(pseries_cpuidle_devices, hotcpu);
> +			per_cpu_ptr(cpuidle_devices, hotcpu);
>
>   	if (dev && cpuidle_get_driver()) {
>   		switch (action) {
> @@ -250,48 +249,6 @@ static int pseries_cpuidle_driver_init(void)
>   	return 0;
>   }
>
> -/* pseries_idle_devices_uninit(void)
> - * unregister cpuidle devices and de-allocate memory
> - */
> -static void pseries_idle_devices_uninit(void)
> -{
> -	int i;
> -	struct cpuidle_device *dev;
> -
> -	for_each_possible_cpu(i) {
> -		dev = per_cpu_ptr(pseries_cpuidle_devices, i);
> -		cpuidle_unregister_device(dev);
> -	}
> -
> -	free_percpu(pseries_cpuidle_devices);
> -	return;
> -}
> -
> -/* pseries_idle_devices_init()
> - * allocate, initialize and register cpuidle device
> - */
> -static int pseries_idle_devices_init(void)
> -{
> -	int i;
> -	struct cpuidle_device *dev;
> -
> -	pseries_cpuidle_devices = alloc_percpu(struct cpuidle_device);
> -	if (pseries_cpuidle_devices == NULL)
> -		return -ENOMEM;
> -
> -	for_each_possible_cpu(i) {
> -		dev = per_cpu_ptr(pseries_cpuidle_devices, i);
> -		dev->cpu = i;
> -		if (cpuidle_register_device(dev)) {
> -			printk(KERN_DEBUG \
> -				"cpuidle_register_device %d failed!\n", i);
> -			return -EIO;
> -		}
> -	}
> -
> -	return 0;
> -}
> -
>   /*
>    * pseries_idle_probe()
>    * Choose state table for shared versus dedicated partition
> @@ -327,19 +284,12 @@ static int __init pseries_processor_idle_init(void)
>   		return retval;
>
>   	pseries_cpuidle_driver_init();
> -	retval = cpuidle_register_driver(&pseries_idle_driver);
> +	retval = cpuidle_register(&pseries_idle_driver, NULL);
>   	if (retval) {
>   		printk(KERN_DEBUG "Registration of pseries driver failed.\n");
>   		return retval;
>   	}
>
> -	retval = pseries_idle_devices_init();
> -	if (retval) {
> -		pseries_idle_devices_uninit();
> -		cpuidle_unregister_driver(&pseries_idle_driver);
> -		return retval;
> -	}
> -
>   	register_cpu_notifier(&setup_hotplug_notifier);
>   	printk(KERN_DEBUG "pseries_idle_driver registered\n");
>
> @@ -350,8 +300,7 @@ static void __exit pseries_processor_idle_exit(void)
>   {
>
>   	unregister_cpu_notifier(&setup_hotplug_notifier);
> -	pseries_idle_devices_uninit();
> -	cpuidle_unregister_driver(&pseries_idle_driver);
> +	cpuidle_unregister(&pseries_idle_driver);
>
>   	return;
>   }
>


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Re: [PATCH 0/9] cpuidle: rework device state count handling

[Rafael J. Wysocki]

On Thursday, September 26, 2013 12:40:17 PM Daniel Lezcano wrote:
> On 09/23/2013 06:05 PM, Bartlomiej Zolnierkiewicz wrote:
> >
> > Hi Daniel,
> >
> > Did you have a chance to take a look at this patchset?
> >
> > Could it be queued for 3.13 (unfortunately it is probably too late for 3.12)?
> 
> Thanks for the head up, I will review it.
> 
> Unfortunately this patchset did not get any acked-by from the different 
> maintainers. Furthermore I believe it would be up to Rafael to take them.


I need to discuss them with Len and that won't happen before Oct 6 I'm afraid.

Thanks,
Rafael

Re: [PATCH 0/9] cpuidle: rework device state count handling

[Bartlomiej Zolnierkiewicz]

Hi,

On Friday, September 27, 2013 03:04:39 AM Rafael J. Wysocki wrote:
> On Thursday, September 26, 2013 12:40:17 PM Daniel Lezcano wrote:
> > On 09/23/2013 06:05 PM, Bartlomiej Zolnierkiewicz wrote:
> > >
> > > Hi Daniel,
> > >
> > > Did you have a chance to take a look at this patchset?
> > >
> > > Could it be queued for 3.13 (unfortunately it is probably too late for 3.12)?
> > 
> > Thanks for the head up, I will review it.
> > 
> > Unfortunately this patchset did not get any acked-by from the different 
> > maintainers. Furthermore I believe it would be up to Rafael to take them.
> 
> 
> I need to discuss them with Len and that won't happen before Oct 6 I'm afraid.

Any news about status of this patchset?

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics