Re: [RFC PATCH 5/5] kvm_main: replace debugfs with statsfs

[Emanuele Giuseppe Esposito <eesposit@redhat.com>]

On 4/28/20 7:56 PM, Randy Dunlap wrote:
> On 4/27/20 7:18 AM, Emanuele Giuseppe Esposito wrote:
>> Use statsfs API instead of debugfs to create sources and add values.
>>
>> This also requires to change all architecture files to replace the old
>> debugfs_entries with statsfs_vcpu_entries and statsfs_vm_entries.
>>
>> The files/folders name and organization is kept unchanged, and a symlink
>> in sys/kernel/debugfs/kvm is left for backward compatibility.
>>
>> Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
>> ---
>>   arch/arm64/kvm/guest.c          |   2 +-
>>   arch/mips/kvm/mips.c            |   2 +-
>>   arch/powerpc/kvm/book3s.c       |   6 +-
>>   arch/powerpc/kvm/booke.c        |   8 +-
>>   arch/s390/kvm/kvm-s390.c        |  16 +-
>>   arch/x86/include/asm/kvm_host.h |   2 +-
>>   arch/x86/kvm/Makefile           |   2 +-
>>   arch/x86/kvm/debugfs.c          |  64 -------
>>   arch/x86/kvm/statsfs.c          |  49 +++++
>>   arch/x86/kvm/x86.c              |   6 +-
>>   include/linux/kvm_host.h        |  39 +---
>>   virt/kvm/arm/arm.c              |   2 +-
>>   virt/kvm/kvm_main.c             | 314 ++++----------------------------
>>   13 files changed, 130 insertions(+), 382 deletions(-)
>>   delete mode 100644 arch/x86/kvm/debugfs.c
>>   create mode 100644 arch/x86/kvm/statsfs.c
> 
> 
> You might want to select STATS_FS here (or depend on it if it is required),
> or you could provide stubs in <linux/statsfs.h> for the cases of STATS_FS
> is not set/enabled.

Currently debugfs is not present in the kvm Kconfig, but implements 
empty stubs as you suggested. I guess it would be a good idea to do the 
same for statsfs.

Paolo, what do you think?

Regarding the other suggestions, you are right, I will apply them in v2.

Thank you,
Emanuele