Re: [Qemu-devel] [RFC PATCH V2 0/3] Multithread TCG async_safe_work part.

["Alex Bennée" <alex.bennee@linaro.org>]

Paolo Bonzini <pbonzini@redhat.com> writes:

> On 10/07/2015 18:08, fred.konrad@greensocs.com wrote:
>> From: KONRAD Frederic <fred.konrad@greensocs.com>
>> 
>> This is the async_safe_work introduction bit of the Multithread TCG work.
>> Rebased on current upstream (6169b60285fe1ff730d840a49527e721bfb30899).
>> 
>> It can be cloned here:
>> http://git.greensocs.com/fkonrad/mttcg.git branch async_work_v2
>> 
>> The first patch introduces a mutex to protect the existing queued_work_*
>> CPUState members against multiple (concurent) access.
>> 
>> The second patch introduces a tcg_executing_flag which will be 1 when we are
>> inside cpu_exec(). This is required as safe work need to be sure that's all vCPU
>> are outside cpu_exec().
>> 
>> The last patch introduces async_safe_work. It allows to add some work which will
>> be done asynchronously but only when all vCPUs are outside cpu_exec(). The tcg
>> thread will wait that no vCPUs have any pending safe work before reentering
>> cpu-exec().
>> 
>> Changes V1 -> V2:
>>   * Release the lock while running the callback for both async and safe work.
>
> What tree do these patches apply to?

See Fred's tree:

http://git.greensocs.com/fkonrad/mttcg

>
> Paolo
>
>> KONRAD Frederic (3):
>>   cpus: protect queued_work_* with work_mutex.
>>   cpus: add a tcg_executing flag.
>>   cpus: introduce async_run_safe_work_on_cpu.
>> 
>>  cpu-exec.c        |   7 +++
>>  cpus.c            | 164 +++++++++++++++++++++++++++++++++++++++++-------------
>>  include/qom/cpu.h |  28 ++++++++++
>>  qom/cpu.c         |   2 +
>>  4 files changed, 161 insertions(+), 40 deletions(-)
>> 

-- 
Alex Bennée