Re: [PATCH] apic: Report current_count via 'info lapic'

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 2/6/20 8:50 PM, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
> 
> This is helpful when debugging stuck guest timers.
> 
> As we need apic_get_current_count for that, and it is really not
> emulation specific, move it to apic_common.c and export it.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>   hw/intc/apic.c                  | 18 ------------------
>   hw/intc/apic_common.c           | 18 ++++++++++++++++++
>   include/hw/i386/apic_internal.h |  1 +
>   target/i386/helper.c            |  5 +++--
>   4 files changed, 22 insertions(+), 20 deletions(-)
> 
> diff --git a/hw/intc/apic.c b/hw/intc/apic.c
> index bd40467965..f2207d0ace 100644
> --- a/hw/intc/apic.c
> +++ b/hw/intc/apic.c
> @@ -615,24 +615,6 @@ int apic_accept_pic_intr(DeviceState *dev)
>       return 0;
>   }
>   
> -static uint32_t apic_get_current_count(APICCommonState *s)
> -{
> -    int64_t d;
> -    uint32_t val;
> -    d = (qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - s->initial_count_load_time) >>
> -        s->count_shift;
> -    if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_TIMER_PERIODIC) {
> -        /* periodic */
> -        val = s->initial_count - (d % ((uint64_t)s->initial_count + 1));
> -    } else {
> -        if (d >= s->initial_count)
> -            val = 0;
> -        else
> -            val = s->initial_count - d;
> -    }
> -    return val;
> -}
> -
>   static void apic_timer_update(APICCommonState *s, int64_t current_time)
>   {
>       if (apic_next_timer(s, current_time)) {
> diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
> index 9ec0f2deb2..6f4e877878 100644
> --- a/hw/intc/apic_common.c
> +++ b/hw/intc/apic_common.c
> @@ -189,6 +189,24 @@ bool apic_next_timer(APICCommonState *s, int64_t current_time)
>       return true;
>   }
>   
> +uint32_t apic_get_current_count(APICCommonState *s)
> +{
> +    int64_t d;
> +    uint32_t val;
> +    d = (qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - s->initial_count_load_time) >>
> +        s->count_shift;
> +    if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_TIMER_PERIODIC) {
> +        /* periodic */
> +        val = s->initial_count - (d % ((uint64_t)s->initial_count + 1));
> +    } else {
> +        if (d >= s->initial_count)
> +            val = 0;
> +        else
> +            val = s->initial_count - d;

Using QEMU style if () {} else {}:
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> +    }
> +    return val;
> +}
> +
>   void apic_init_reset(DeviceState *dev)
>   {
>       APICCommonState *s;
> diff --git a/include/hw/i386/apic_internal.h b/include/hw/i386/apic_internal.h
> index b04bdd947f..2597000e03 100644
> --- a/include/hw/i386/apic_internal.h
> +++ b/include/hw/i386/apic_internal.h
> @@ -211,6 +211,7 @@ void vapic_report_tpr_access(DeviceState *dev, CPUState *cpu, target_ulong ip,
>                                TPRAccess access);
>   
>   int apic_get_ppr(APICCommonState *s);
> +uint32_t apic_get_current_count(APICCommonState *s);
>   
>   static inline void apic_set_bit(uint32_t *tab, int index)
>   {
> diff --git a/target/i386/helper.c b/target/i386/helper.c
> index c3a6e4fabe..e3c3726c29 100644
> --- a/target/i386/helper.c
> +++ b/target/i386/helper.c
> @@ -370,10 +370,11 @@ void x86_cpu_dump_local_apic_state(CPUState *cs, int flags)
>       dump_apic_lvt("LVTTHMR", lvt[APIC_LVT_THERMAL], false);
>       dump_apic_lvt("LVTT", lvt[APIC_LVT_TIMER], true);
>   
> -    qemu_printf("Timer\t DCR=0x%x (divide by %u) initial_count = %u\n",
> +    qemu_printf("Timer\t DCR=0x%x (divide by %u) initial_count = %u"
> +                " current_count = %u\n",
>                   s->divide_conf & APIC_DCR_MASK,
>                   divider_conf(s->divide_conf),
> -                s->initial_count);
> +                s->initial_count, apic_get_current_count(s));
>   
>       qemu_printf("SPIV\t 0x%08x APIC %s, focus=%s, spurious vec %u\n",
>                   s->spurious_vec,
>