On 04/23/2018 09:41 AM, Christian Borntraeger wrote:
>
>
> On 04/21/2018 12:07 AM, Marc Orr wrote:
>> First off---thanks for reviewing my patch!
>>
>> With respect to the size of the struct, here's what I'm seeing on an
>> upstream
>> version of the kernel:
>>
>> (gdb) p sizeof(struct kvm)
>> $1 = 42200
>> (gdb) p sizeof(struct kvm_arch)
>> $2 = 35496
>
> Yes, I looked at an older kernel on x86. Sorry about that. The newer kernels
> certainly have grown. Would be interesting to see why. Can you run
> pahole (usually in the package dwarves) on you kernel and search for
> "struct kvm "
Seems to be
struct hlist_head mmu_page_hash[4096]; /* 24 32768 */
in kvm_arch.
This is now much larger mostly due to
commit 114df303a7eeae8b50ebf68229b7e647714a9bea
kvm: x86: reduce collisions in mmu_page_hash
So maybe it is enough to allocate mmu_page_hash seperately? Adding David Matlack
for opinions.
