aboutsummaryrefslogtreecommitdiff
path: root/drivers/cpuidle/cpuidle.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-07 09:45:58 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-07 09:45:58 -0800
commitf0f1b3364ae7f48084bdf2837fb979ff59622523 (patch)
treee5ef68c0071f44178cc8d1948b64e216d57422aa /drivers/cpuidle/cpuidle.c
parent4383f18b7f94a4d668c5eec68645c75d44556235 (diff)
parentb7143156c9ceee1a072c57aac8729d2dec5b3bf1 (diff)
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (112 commits) ACPI: fix build warning Revert "cpuidle: build fix for non-x86" ACPI: update intrd DSDT override console messages ACPI: update DSDT override documentation ACPI: Add "acpi_no_initrd_override" kernel parameter ACPI: its a directory not a folder.... ACPI: misc cleanups ACPI: add missing prink prefix strings ACPI: cleanup acpi.h ACPICA: fix CONFIG_ACPI_DEBUG_FUNC_TRACE build ACPI: video: Ignore ACPI video devices that aren't present in hardware ACPI: video: reset brightness on resume ACPI: video: call ACPI notifier chain for ACPI video notifications ACPI: create notifier chain to get hotkey events to graphics driver ACPI: video: delete unused display switch on hotkey event code ACPI: video: create "brightness_switch_enabled" modparam cpuidle: Add a poll_idle method ACPI: cpuidle: Support C1 idle time accounting ACPI: enable MWAIT for C1 idle ACPI: idle: Fix acpi_safe_halt usages and interrupt enabling/disabling ...
Diffstat (limited to 'drivers/cpuidle/cpuidle.c')
-rw-r--r--drivers/cpuidle/cpuidle.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 2a98d99cbd4..2c4b2d47973 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -15,6 +15,7 @@
#include <linux/pm_qos_params.h>
#include <linux/cpu.h>
#include <linux/cpuidle.h>
+#include <linux/ktime.h>
#include "cpuidle.h"
@@ -180,6 +181,44 @@ void cpuidle_disable_device(struct cpuidle_device *dev)
EXPORT_SYMBOL_GPL(cpuidle_disable_device);
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st)
+{
+ ktime_t t1, t2;
+ s64 diff;
+ int ret;
+
+ t1 = ktime_get();
+ local_irq_enable();
+ while (!need_resched())
+ cpu_relax();
+
+ t2 = ktime_get();
+ diff = ktime_to_us(ktime_sub(t2, t1));
+ if (diff > INT_MAX)
+ diff = INT_MAX;
+
+ ret = (int) diff;
+ return ret;
+}
+
+static void poll_idle_init(struct cpuidle_device *dev)
+{
+ struct cpuidle_state *state = &dev->states[0];
+
+ cpuidle_set_statedata(state, NULL);
+
+ snprintf(state->name, CPUIDLE_NAME_LEN, "C0 (poll idle)");
+ state->exit_latency = 0;
+ state->target_residency = 0;
+ state->power_usage = -1;
+ state->flags = CPUIDLE_FLAG_POLL | CPUIDLE_FLAG_TIME_VALID;
+ state->enter = poll_idle;
+}
+#else
+static void poll_idle_init(struct cpuidle_device *dev) {}
+#endif /* CONFIG_ARCH_HAS_CPU_RELAX */
+
/**
* cpuidle_register_device - registers a CPU's idle PM feature
* @dev: the cpu
@@ -198,6 +237,8 @@ int cpuidle_register_device(struct cpuidle_device *dev)
mutex_lock(&cpuidle_lock);
+ poll_idle_init(dev);
+
per_cpu(cpuidle_devices, dev->cpu) = dev;
list_add(&dev->device_list, &cpuidle_detected_devices);
if ((ret = cpuidle_add_sysfs(sys_dev))) {