Re: [Qemu-devel] [PATCH v2 01/10] hw/mips/cputimer: Don't start periodic timer in KVM mode

[Aurelien Jarno <aurelien@aurel32.net>]

On Mon, Dec 16, 2013 at 02:12:36PM +0000, James Hogan wrote:
> From: Sanjay Lal <sanjayl@kymasys.com>
> 
> Compare/Count timer interrupts are handled in-kernel for KVM, so don't
> bother starting it in QEMU.
> 
> Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
> Signed-off-by: James Hogan <james.hogan@imgtec.com>
> Cc: Aurelien Jarno <aurelien@aurel32.net>
> ---
> Changes in v2:
>  - Expand commit message
>  - Rebase on v1.7.0
>  - Wrap comment
> ---
>  hw/mips/cputimer.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/mips/cputimer.c b/hw/mips/cputimer.c
> index c8b4b00..52570fd 100644
> --- a/hw/mips/cputimer.c
> +++ b/hw/mips/cputimer.c
> @@ -23,6 +23,7 @@
>  #include "hw/hw.h"
>  #include "hw/mips/cpudevs.h"
>  #include "qemu/timer.h"
> +#include "sysemu/kvm.h"
>  
>  #define TIMER_FREQ	100 * 1000 * 1000
>  
> @@ -141,7 +142,13 @@ static void mips_timer_cb (void *opaque)
>  
>  void cpu_mips_clock_init (CPUMIPSState *env)
>  {
> -    env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &mips_timer_cb, env);
> -    env->CP0_Compare = 0;
> -    cpu_mips_store_count(env, 1);
> +    /*
> +     * If we're in KVM mode, don't start the periodic timer, that is handled in
> +     * kernel.
> +     */
> +    if (!kvm_enabled()) {
> +        env->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &mips_timer_cb, env);
> +        env->CP0_Compare = 0;
> +        cpu_mips_store_count(env, 1);
> +    }
>  }

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net