Re: [Qemu-devel] [PATCH qemu] hmp: Print if memory section is registered in KVM

[Paolo Bonzini <pbonzini@redhat.com>]

On 13/11/2018 15:51, Dr. David Alan Gilbert wrote:
> * Alexey Kardashevskiy (aik@ozlabs.ru) wrote:
>> This adds a "KVM" marker to the "into mtree -f" to tell the user if
>> a particular memory section is registered as a KVM memory slot; useful
>> for debugging purposes.
>>
>> Since it is memory sections which get registered in KVM (rather than
>> memory regions), this only prints "KVM" for flatviews.
>>
>> For example:
>>  Root memory region: system
>>   0000000000000000-00000003ffffffff (prio 0, ram): ppc_spapr.ram KVM
>>   0000200000000020-000020000000003f (prio 1, i/o): virtio-pci
>>
>> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> 
> From HMP I'm ok with this, but I wonder if we should make this
> code more general to other accelerators and not specific to kvm?

Can't this be derived from the type (ram, i/o, ...)?

Paolo

> 
> Dave
> 
>> ---
>>  include/sysemu/kvm.h |  1 +
>>  accel/kvm/kvm-all.c  |  7 +++++++
>>  memory.c             | 10 ++++++++++
>>  3 files changed, 18 insertions(+)
>>
>> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
>> index 97d8d9d0d5..9eab5ac1b1 100644
>> --- a/include/sysemu/kvm.h
>> +++ b/include/sysemu/kvm.h
>> @@ -471,6 +471,7 @@ void kvm_set_sigmask_len(KVMState *s, unsigned int sigmask_len);
>>  #if !defined(CONFIG_USER_ONLY)
>>  int kvm_physical_memory_addr_from_host(KVMState *s, void *ram_addr,
>>                                         hwaddr *phys_addr);
>> +bool is_kvm_memory(hwaddr start_addr, hwaddr size);
>>  #endif
>>  
>>  #endif /* NEED_CPU_H */
>> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
>> index 4880a05399..d72808aaa6 100644
>> --- a/accel/kvm/kvm-all.c
>> +++ b/accel/kvm/kvm-all.c
>> @@ -216,6 +216,13 @@ static KVMSlot *kvm_lookup_matching_slot(KVMMemoryListener *kml,
>>      return NULL;
>>  }
>>  
>> +bool is_kvm_memory(hwaddr start_addr, hwaddr size)
>> +{
>> +    KVMMemoryListener *kml = &kvm_state->memory_listener;
>> +
>> +    return NULL != kvm_lookup_matching_slot(kml, start_addr, size);
>> +}
>> +
>>  /*
>>   * Calculate and align the start address and the size of the section.
>>   * Return the size. If the size is 0, the aligned section is empty.
>> diff --git a/memory.c b/memory.c
>> index 51204aa079..56c733c687 100644
>> --- a/memory.c
>> +++ b/memory.c
>> @@ -2916,6 +2916,7 @@ static void mtree_print_flatview(gpointer key, gpointer value,
>>      int n = view->nr;
>>      int i;
>>      AddressSpace *as;
>> +    bool print_kvm = false;
>>  
>>      p(f, "FlatView #%d\n", fvi->counter);
>>      ++fvi->counter;
>> @@ -2927,6 +2928,9 @@ static void mtree_print_flatview(gpointer key, gpointer value,
>>              p(f, ", alias %s", memory_region_name(as->root->alias));
>>          }
>>          p(f, "\n");
>> +        if (as == &address_space_memory) {
>> +            print_kvm = true;
>> +        }
>>      }
>>  
>>      p(f, " Root memory region: %s\n",
>> @@ -2960,6 +2964,12 @@ static void mtree_print_flatview(gpointer key, gpointer value,
>>          if (fvi->owner) {
>>              mtree_print_mr_owner(p, f, mr);
>>          }
>> +
>> +        if (kvm_enabled() && print_kvm &&
>> +            is_kvm_memory(int128_get64(range->addr.start),
>> +                          MR_SIZE(range->addr.size) + 1)) {
>> +            p(f, " KVM");
>> +        }
>>          p(f, "\n");
>>          range++;
>>      }
>> -- 
>> 2.17.1
>>
>>
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>