exec: drop BQL from interrupt handling

[Qemu-devel] [PATCH 32/35] target/i386/kvm: do not acquire the BQL to call cpu_reset_interrupt

Posted by Emilio G. Cota 7 years, 1 month ago

From: Paolo Bonzini <pbonzini@redhat.com>

It's not needed anymore.

Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 target/i386/kvm.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index e40c8d5461..41c4830be8 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -3007,9 +3007,7 @@ void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run)
     /* Inject NMI */
     if (interrupt_request & (CPU_INTERRUPT_NMI | CPU_INTERRUPT_SMI)) {
         if (interrupt_request & CPU_INTERRUPT_NMI) {
-            qemu_mutex_lock_iothread();
             cpu_reset_interrupt(cpu, CPU_INTERRUPT_NMI);
-            qemu_mutex_unlock_iothread();
             DPRINTF("injected NMI\n");
             ret = kvm_vcpu_ioctl(cpu, KVM_NMI);
             if (ret < 0) {
@@ -3018,9 +3016,7 @@ void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run)
             }
         }
         if (atomic_read(&cpu->interrupt_request) & CPU_INTERRUPT_SMI) {
-            qemu_mutex_lock_iothread();
             cpu_reset_interrupt(cpu, CPU_INTERRUPT_SMI);
-            qemu_mutex_unlock_iothread();
             DPRINTF("injected SMI\n");
             ret = kvm_vcpu_ioctl(cpu, KVM_SMI);
             if (ret < 0) {
-- 
2.17.1

Re: [Qemu-devel] [PATCH 32/35] target/i386/kvm: do not acquire the BQL to call cpu_reset_interrupt

Posted by Richard Henderson 7 years, 1 month ago

On 9/17/18 9:31 AM, Emilio G. Cota wrote:
> From: Paolo Bonzini <pbonzini@redhat.com>
> 
> It's not needed anymore.
> 
> Cc: Marcelo Tosatti <mtosatti@redhat.com>
> Cc: Richard Henderson <rth@twiddle.net>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> Cc: kvm@vger.kernel.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Emilio G. Cota <cota@braap.org>
> ---
>  target/i386/kvm.c | 4 ----
>  1 file changed, 4 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~

Re: [Qemu-devel] [PATCH 32/35] target/i386/kvm: do not acquire the BQL to call cpu_reset_interrupt

Posted by Philippe Mathieu-Daudé 7 years, 1 month ago

On 9/17/18 6:31 PM, Emilio G. Cota wrote:
> From: Paolo Bonzini <pbonzini@redhat.com>
> 
> It's not needed anymore.
> 
> Cc: Marcelo Tosatti <mtosatti@redhat.com>
> Cc: Richard Henderson <rth@twiddle.net>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> Cc: kvm@vger.kernel.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Emilio G. Cota <cota@braap.org>

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

> ---
>  target/i386/kvm.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index e40c8d5461..41c4830be8 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -3007,9 +3007,7 @@ void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run)
>      /* Inject NMI */
>      if (interrupt_request & (CPU_INTERRUPT_NMI | CPU_INTERRUPT_SMI)) {
>          if (interrupt_request & CPU_INTERRUPT_NMI) {
> -            qemu_mutex_lock_iothread();
>              cpu_reset_interrupt(cpu, CPU_INTERRUPT_NMI);
> -            qemu_mutex_unlock_iothread();
>              DPRINTF("injected NMI\n");
>              ret = kvm_vcpu_ioctl(cpu, KVM_NMI);
>              if (ret < 0) {
> @@ -3018,9 +3016,7 @@ void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run)
>              }
>          }
>          if (atomic_read(&cpu->interrupt_request) & CPU_INTERRUPT_SMI) {
> -            qemu_mutex_lock_iothread();
>              cpu_reset_interrupt(cpu, CPU_INTERRUPT_SMI);
> -            qemu_mutex_unlock_iothread();
>              DPRINTF("injected SMI\n");
>              ret = kvm_vcpu_ioctl(cpu, KVM_SMI);
>              if (ret < 0) {
>