Re: [Qemu-devel] [PULL 09/27] migration: calculate vCPU blocktime on dst side

[Juan Quintela]

Max Reitz <address@hidden> wrote:
> On 2018-01-15 12:52, Juan Quintela wrote:
>> From: Alexey Perevalov <address@hidden>
>> 
>> This patch provides blocktime calculation per vCPU,
>> as a summary and as a overlapped value for all vCPUs.
>> 
>> This approach was suggested by Peter Xu, as an improvements of
>> previous approch where QEMU kept tree with faulted page address and cpus 
>> bitmask
>> in it. Now QEMU is keeping array with faulted page address as value and vCPU
>> as index. It helps to find proper vCPU at UFFD_COPY time. Also it keeps
>> list for blocktime per vCPU (could be traced with page_fault_addr)
>> 
>> Blocktime will not calculated if postcopy_blocktime field of
>> MigrationIncomingState wasn't initialized.
>> 
>> Signed-off-by: Alexey Perevalov <address@hidden>
>> Reviewed-by: Dr. David Alan Gilbert <address@hidden>
>> Reviewed-by: Juan Quintela <address@hidden>
>> Signed-off-by: Juan Quintela <address@hidden>
>> ---
>>  migration/postcopy-ram.c | 143 
>> ++++++++++++++++++++++++++++++++++++++++++++++-
>>  migration/trace-events   |   5 +-
>>  2 files changed, 146 insertions(+), 2 deletions(-)
>
> For me, this breaks compilation with clang -m32:
>
>   LINK    x86_64-softmmu/qemu-system-x86_64
> ../migration/postcopy-ram.o: In function `mark_postcopy_blocktime_begin':
> /home/maxx/projects/qemu/migration/postcopy-ram.c:599: undefined
> reference to `__atomic_exchange_8'
> /home/maxx/projects/qemu/migration/postcopy-ram.c:600: undefined
> reference to `__atomic_exchange_8'
> /home/maxx/projects/qemu/migration/postcopy-ram.c:609: undefined
> reference to `__atomic_exchange_8'
> ../migration/postcopy-ram.o: In function `mark_postcopy_blocktime_end':
> /home/maxx/projects/qemu/migration/postcopy-ram.c:665: undefined
> reference to `__atomic_fetch_add_8'
> /home/maxx/projects/qemu/migration/postcopy-ram.c:686: undefined
> reference to `__atomic_fetch_add_8'
>
> Am I doing something wrong?

I have never used clang so .... I guess I should install.

I am assuming you are using x86 here, right?

Later, Juan.