diff options
Diffstat (limited to 'arch/x86/kernel/acpi/cstate.c')
-rw-r--r-- | arch/x86/kernel/acpi/cstate.c | 23 |
1 files changed, 0 insertions, 23 deletions
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c index d2b7f27781bc..e69182fd01cf 100644 --- a/arch/x86/kernel/acpi/cstate.c +++ b/arch/x86/kernel/acpi/cstate.c | |||
@@ -150,29 +150,6 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu, | |||
150 | } | 150 | } |
151 | EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe); | 151 | EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe); |
152 | 152 | ||
153 | /* | ||
154 | * This uses new MONITOR/MWAIT instructions on P4 processors with PNI, | ||
155 | * which can obviate IPI to trigger checking of need_resched. | ||
156 | * We execute MONITOR against need_resched and enter optimized wait state | ||
157 | * through MWAIT. Whenever someone changes need_resched, we would be woken | ||
158 | * up from MWAIT (without an IPI). | ||
159 | * | ||
160 | * New with Core Duo processors, MWAIT can take some hints based on CPU | ||
161 | * capability. | ||
162 | */ | ||
163 | void mwait_idle_with_hints(unsigned long ax, unsigned long cx) | ||
164 | { | ||
165 | if (!need_resched()) { | ||
166 | if (this_cpu_has(X86_FEATURE_CLFLUSH_MONITOR)) | ||
167 | clflush((void *)¤t_thread_info()->flags); | ||
168 | |||
169 | __monitor((void *)¤t_thread_info()->flags, 0, 0); | ||
170 | smp_mb(); | ||
171 | if (!need_resched()) | ||
172 | __mwait(ax, cx); | ||
173 | } | ||
174 | } | ||
175 | |||
176 | void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cx) | 153 | void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cx) |
177 | { | 154 | { |
178 | unsigned int cpu = smp_processor_id(); | 155 | unsigned int cpu = smp_processor_id(); |