[PATCH v7 04/10] cpuidle-haltpoll: define arch_haltpoll_want()

[Ankur Arora]

From: Joao Martins <joao.m.martins at oracle.com>

kvm_para_has_hint(KVM_HINTS_REALTIME) is defined only on x86. In
pursuit of making cpuidle-haltpoll architecture independent, define
arch_haltpoll_want() which handles the architectural checks for
enabling haltpoll.

Signed-off-by: Joao Martins <joao.m.martins at oracle.com>
Signed-off-by: Mihai Carabas <mihai.carabas at oracle.com>
Signed-off-by: Ankur Arora <ankur.a.arora at oracle.com>
---
 arch/x86/include/asm/cpuidle_haltpoll.h |  1 +
 arch/x86/kernel/kvm.c                   | 13 +++++++++++++
 drivers/cpuidle/cpuidle-haltpoll.c      | 12 +-----------
 include/linux/cpuidle_haltpoll.h        |  5 +++++
 4 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/cpuidle_haltpoll.h b/arch/x86/include/asm/cpuidle_haltpoll.h
index c8b39c6716ff..8a0a12769c2e 100644
--- a/arch/x86/include/asm/cpuidle_haltpoll.h
+++ b/arch/x86/include/asm/cpuidle_haltpoll.h
@@ -4,5 +4,6 @@
 
 void arch_haltpoll_enable(unsigned int cpu);
 void arch_haltpoll_disable(unsigned int cpu);
+bool arch_haltpoll_want(bool force);
 
 #endif
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 263f8aed4e2c..63710cb1aa63 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -1151,4 +1151,17 @@ void arch_haltpoll_disable(unsigned int cpu)
 	smp_call_function_single(cpu, kvm_enable_host_haltpoll, NULL, 1);
 }
 EXPORT_SYMBOL_GPL(arch_haltpoll_disable);
+
+bool arch_haltpoll_want(bool force)
+{
+	/* Do not load haltpoll if idle= is passed */
+	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
+		return false;
+
+	if (!kvm_para_available())
+		return false;
+
+	return kvm_para_has_hint(KVM_HINTS_REALTIME) || force;
+}
+EXPORT_SYMBOL_GPL(arch_haltpoll_want);
 #endif
diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c
index bcd03e893a0a..e532aa2bf608 100644
--- a/drivers/cpuidle/cpuidle-haltpoll.c
+++ b/drivers/cpuidle/cpuidle-haltpoll.c
@@ -15,7 +15,6 @@
 #include <linux/cpuidle.h>
 #include <linux/module.h>
 #include <linux/sched/idle.h>
-#include <linux/kvm_para.h>
 #include <linux/cpuidle_haltpoll.h>
 
 static bool force __read_mostly;
@@ -93,21 +92,12 @@ static void haltpoll_uninit(void)
 	haltpoll_cpuidle_devices = NULL;
 }
 
-static bool haltpoll_want(void)
-{
-	return kvm_para_has_hint(KVM_HINTS_REALTIME) || force;
-}
-
 static int __init haltpoll_init(void)
 {
 	int ret;
 	struct cpuidle_driver *drv = &haltpoll_driver;
 
-	/* Do not load haltpoll if idle= is passed */
-	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
-		return -ENODEV;
-
-	if (!kvm_para_available() || !haltpoll_want())
+	if (!arch_haltpoll_want(force))
 		return -ENODEV;
 
 	cpuidle_poll_state_init(drv);
diff --git a/include/linux/cpuidle_haltpoll.h b/include/linux/cpuidle_haltpoll.h
index d50c1e0411a2..68eb7a757120 100644
--- a/include/linux/cpuidle_haltpoll.h
+++ b/include/linux/cpuidle_haltpoll.h
@@ -12,5 +12,10 @@ static inline void arch_haltpoll_enable(unsigned int cpu)
 static inline void arch_haltpoll_disable(unsigned int cpu)
 {
 }
+
+static inline bool arch_haltpoll_want(bool force)
+{
+	return false;
+}
 #endif
 #endif
-- 
2.43.5