Re: [Qemu-devel] [PATCH 6/6] xics: implement xics_ics_free()

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 05/08/2014 10:07 PM, Alexander Graf wrote:
> On 05/07/2014 08:01 AM, Alexey Kardashevskiy wrote:
>> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
>> ---
>>   hw/intc/xics.c        | 24 ++++++++++++++++++++++++
>>   include/hw/ppc/xics.h |  1 +
>>   trace-events          |  2 ++
>>   3 files changed, 27 insertions(+)
>>
>> diff --git a/hw/intc/xics.c b/hw/intc/xics.c
>> index faf304c..2316519 100644
>> --- a/hw/intc/xics.c
>> +++ b/hw/intc/xics.c
>> @@ -755,6 +755,30 @@ int xics_alloc_block(XICSState *icp, int server, int
>> num, bool lsi, bool align)
>>       return first + ics->offset;
>>   }
>>   +static void ics_free(ICSState *ics, int srcno, int num)
>> +{
>> +    int i;
>> +
>> +    for (i = srcno; i < srcno + num; ++i) {
>> +        if (ICS_IRQ_FREE(ics, i)) {
>> +            trace_xics_ics_free_warn(ics - ics->icp->ics, i + ics->offset);
>> +        }
>> +        memset(&ics->irqs[i], 0, sizeof(ICSIRQState));
> 
> Why does this do something different from ics_reset?


ics_reset() resets the interrupt state which still remains allocated and
assigned to some device. ics_free() clears the descriptor and this
interrupt may be now returned if someone asks for a new interrupt (pci
hotplug, intx->msi switch).


> Alex
> 
>> +    }
>> +}
>> +
>> +void xics_free(XICSState *icp, int server, int irq, int num)
>> +{
>> +    ICSState *ics = &icp->ics[server];
>> +
>> +    assert(server == 0);
>> +
>> +    trace_xics_ics_free(ics - icp->ics, irq, num);
>> +    if (server >= 0) {
>> +        ics_free(ics, irq - ics->offset, num);
>> +    }
>> +}
>> +
>>   /*
>>    * Guest interfaces
>>    */
>> diff --git a/include/hw/ppc/xics.h b/include/hw/ppc/xics.h
>> index 0f01a21..e5d8f47 100644
>> --- a/include/hw/ppc/xics.h
>> +++ b/include/hw/ppc/xics.h
>> @@ -158,6 +158,7 @@ struct ICSIRQState {
>>   qemu_irq xics_get_qirq(XICSState *icp, int irq);
>>   int xics_alloc(XICSState *icp, int server, int irq_hint, bool lsi);
>>   int xics_alloc_block(XICSState *icp, int server, int num, bool lsi,
>> bool align);
>> +void xics_free(XICSState *icp, int server, int irq, int num);
>>     void xics_cpu_setup(XICSState *icp, PowerPCCPU *cpu);
>>   diff --git a/trace-events b/trace-events
>> index 8cf8fb2..5ca126c 100644
>> --- a/trace-events
>> +++ b/trace-events
>> @@ -1179,6 +1179,8 @@ xics_alloc(int server, int irq) "server#%d, irq %d"
>>   xics_alloc_failed_hint(int server, int irq) "server#%d, irq %d is
>> already in use"
>>   xics_alloc_failed_no_left(int server) "server#%d, no irq left"
>>   xics_alloc_block(int server, int first, int num, bool lsi, int align)
>> "server#%d, first irq %d, %d irqs, lsi=%d, alignnum %d"
>> +xics_ics_free(int server, int irq, int num) "server#%d, first irq %d, %d
>> irqs"
>> +xics_ics_free_warn(int server, int irq) "server#%d, irq %d is already free"
>>     # hw/ppc/spapr_iommu.c
>>   spapr_iommu_put(uint64_t liobn, uint64_t ioba, uint64_t tce, uint64_t
>> ret) "liobn=%"PRIx64" ioba=0x%"PRIx64" tce=0x%"PRIx64" ret=%"PRId64
> 


-- 
Alexey