[2/7] x86/kvm: Move haltpoll_want() to be arch defined

Message ID 1700488898-12431-3-git-send-email-mihai.carabas@oracle.com
State New
Headers
Series [1/7] x86: Move ARCH_HAS_CPU_RELAX to arch |

Commit Message

Mihai Carabas Nov. 20, 2023, 2:01 p.m. UTC
  From: Joao Martins <joao.m.martins@oracle.com>

Right now, kvm_para_has_hint(KVM_HINTS_REALTIME) is x86 only, and so in the
pursuit of making cpuidle-haltpoll arch independent, move the check for
haltpoll enablement to be defined per architecture. Same thing for
boot_option_idle_override. To that end, add a arch_haltpoll_want() and move the
check there.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>
---
 arch/x86/include/asm/cpuidle_haltpoll.h |  1 +
 arch/x86/kernel/kvm.c                   | 10 ++++++++++
 drivers/cpuidle/cpuidle-haltpoll.c      |  8 ++------
 include/linux/cpuidle_haltpoll.h        |  5 +++++
 4 files changed, 18 insertions(+), 6 deletions(-)
  

Comments

Rafael J. Wysocki Nov. 29, 2023, 8:55 p.m. UTC | #1
On Mon, Nov 20, 2023 at 4:15 PM Mihai Carabas <mihai.carabas@oracle.com> wrote:
>
> From: Joao Martins <joao.m.martins@oracle.com>
>
> Right now, kvm_para_has_hint(KVM_HINTS_REALTIME) is x86 only, and so in the
> pursuit of making cpuidle-haltpoll arch independent, move the check for
> haltpoll enablement to be defined per architecture. Same thing for
> boot_option_idle_override. To that end, add a arch_haltpoll_want() and move the
> check there.
>
> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
> Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>

From the cpuidle side:

Acked-by: Rafael J. Wysocki <rafael@kernel.org>

> ---
>  arch/x86/include/asm/cpuidle_haltpoll.h |  1 +
>  arch/x86/kernel/kvm.c                   | 10 ++++++++++
>  drivers/cpuidle/cpuidle-haltpoll.c      |  8 ++------
>  include/linux/cpuidle_haltpoll.h        |  5 +++++
>  4 files changed, 18 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/include/asm/cpuidle_haltpoll.h b/arch/x86/include/asm/cpuidle_haltpoll.h
> index c8b39c6716ff..2c5a53ce266f 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(void);
>
>  #endif
> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> index 1cceac5984da..75a24f107b2a 100644
> --- a/arch/x86/kernel/kvm.c
> +++ b/arch/x86/kernel/kvm.c
> @@ -1151,4 +1151,14 @@ 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(void)
> +{
> +       /* Do not load haltpoll if idle= is passed */
> +       if (boot_option_idle_override != IDLE_NO_OVERRIDE)
> +               return false;
> +
> +       return kvm_para_has_hint(KVM_HINTS_REALTIME);
> +}
> +EXPORT_SYMBOL_GPL(arch_haltpoll_want);
>  #endif
> diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c
> index e66df22f9695..72f9c84990c5 100644
> --- a/drivers/cpuidle/cpuidle-haltpoll.c
> +++ b/drivers/cpuidle/cpuidle-haltpoll.c
> @@ -96,7 +96,7 @@ static void haltpoll_uninit(void)
>
>  static bool haltpoll_want(void)
>  {
> -       return kvm_para_has_hint(KVM_HINTS_REALTIME) || force;
> +       return (kvm_para_available() && arch_haltpoll_want()) || force;
>  }
>
>  static int __init haltpoll_init(void)
> @@ -104,11 +104,7 @@ 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 (!haltpoll_want())
>                 return -ENODEV;
>
>         cpuidle_poll_state_init(drv);
> diff --git a/include/linux/cpuidle_haltpoll.h b/include/linux/cpuidle_haltpoll.h
> index d50c1e0411a2..bae68a6603e3 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(void)
> +{
> +       return false;
> +}
>  #endif
>  #endif
> --
> 1.8.3.1
>
  

Patch

diff --git a/arch/x86/include/asm/cpuidle_haltpoll.h b/arch/x86/include/asm/cpuidle_haltpoll.h
index c8b39c6716ff..2c5a53ce266f 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(void);
 
 #endif
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 1cceac5984da..75a24f107b2a 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -1151,4 +1151,14 @@  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(void)
+{
+	/* Do not load haltpoll if idle= is passed */
+	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
+		return false;
+
+	return kvm_para_has_hint(KVM_HINTS_REALTIME);
+}
+EXPORT_SYMBOL_GPL(arch_haltpoll_want);
 #endif
diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c
index e66df22f9695..72f9c84990c5 100644
--- a/drivers/cpuidle/cpuidle-haltpoll.c
+++ b/drivers/cpuidle/cpuidle-haltpoll.c
@@ -96,7 +96,7 @@  static void haltpoll_uninit(void)
 
 static bool haltpoll_want(void)
 {
-	return kvm_para_has_hint(KVM_HINTS_REALTIME) || force;
+	return (kvm_para_available() && arch_haltpoll_want()) || force;
 }
 
 static int __init haltpoll_init(void)
@@ -104,11 +104,7 @@  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 (!haltpoll_want())
 		return -ENODEV;
 
 	cpuidle_poll_state_init(drv);
diff --git a/include/linux/cpuidle_haltpoll.h b/include/linux/cpuidle_haltpoll.h
index d50c1e0411a2..bae68a6603e3 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(void)
+{
+	return false;
+}
 #endif
 #endif