[PATCH v6 04/10] cpuidle-haltpoll: define arch_haltpoll_want()

From: Ankur Arora
Date: Fri Jul 26 2024 - 16:22:46 EST


From: Joao Martins <joao.m.martins@xxxxxxxxxx>

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@xxxxxxxxxx>
Signed-off-by: Mihai Carabas <mihai.carabas@xxxxxxxxxx>
Signed-off-by: Ankur Arora <ankur.a.arora@xxxxxxxxxx>
---
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 d8515d5c0853..d47906632ce3 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