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Re: [Qemu-devel] [PATCH] correctly check ppr priority during interrupt i
From: |
Jan Kiszka |
Subject: |
Re: [Qemu-devel] [PATCH] correctly check ppr priority during interrupt injection |
Date: |
Mon, 07 Feb 2011 10:52:37 +0100 |
User-agent: |
Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 |
On 2011-02-07 00:45, Yoshiaki Tamura wrote:
> 2011/2/6 Gleb Natapov <address@hidden>:
>>
>> TPR blocks all interrupts in a priority class, so simple "less or
>> equal" check is not enough.
>>
>> Signed-off-by: Gleb Natapov <address@hidden>
>> diff --git a/hw/apic.c b/hw/apic.c
>> index 2f8376a..cbac75d 100644
>> --- a/hw/apic.c
>> +++ b/hw/apic.c
>> @@ -372,19 +372,33 @@ static int apic_get_arb_pri(APICState *s)
>> return 0;
>> }
>>
>> -/* signal the CPU if an irq is pending */
>> -static void apic_update_irq(APICState *s)
>> +
>> +/*
>> + * <0 - low prio interrupt,
>> + * 0 - no interrupt,
>> + * >0 - interrupt number
>> + */
>> +static int apic_irq_pending(APICState *s)
>> {
>> int irrv, ppr;
>> - if (!(s->spurious_vec & APIC_SV_ENABLE))
>> - return;
>> irrv = get_highest_priority_int(s->irr);
>> if (irrv < 0)
>> - return;
>> + return 0;
>> ppr = apic_get_ppr(s);
>> if (ppr && (irrv & 0xf0) <= (ppr & 0xf0))
>> + return -1;
>
> Just a minor point: braces are missing. checkpatch.pl would
> help.
Actually, the code above does not touch lines with missing braces
(though I prefer to clean up the close environment of my patches as
well) but..
>> +
>> + return irrv;
>> +}
>> +
>> +/* signal the CPU if an irq is pending */
>> +static void apic_update_irq(APICState *s)
>> +{
>> + if (!(s->spurious_vec & APIC_SV_ENABLE))
>> return;
...here checkpatch would complain. Also about a trailing whitespace earlier.
Besides those minor issues, patch looks good and works fine. So you can add
Reviewed-by: Jan Kiszka <address@hidden>
on resubmission. Please also add a 0.14 tag, this is a must-have for
stable IMO.
Jan
>> - cpu_interrupt(s->cpu_env, CPU_INTERRUPT_HARD);
>> + if (apic_irq_pending(s) > 0) {
>> + cpu_interrupt(s->cpu_env, CPU_INTERRUPT_HARD);
>> + }
>> }
>>
>> void apic_reset_irq_delivered(void)
>> @@ -590,12 +604,13 @@ int apic_get_interrupt(DeviceState *d)
>> if (!(s->spurious_vec & APIC_SV_ENABLE))
>> return -1;
>>
>> - /* XXX: spurious IRQ handling */
>> - intno = get_highest_priority_int(s->irr);
>> - if (intno < 0)
>> + intno = apic_irq_pending(s);
>> +
>> + if (intno == 0) {
>> return -1;
>> - if (s->tpr && intno <= s->tpr)
>> + } else if (intno < 0) {
>> return s->spurious_vec & 0xff;
>> + }
>> reset_bit(s->irr, intno);
>> set_bit(s->isr, intno);
>> apic_update_irq(s);
>> --
>> Gleb.
>>
>>
--
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