On 03/11/2017 10:16, Pavel Dovgalyuk wrote:
>> From: Paolo Bonzini [mailto:pbonz...@redhat.com]
>> On 31/10/2017 12:26, Pavel Dovgalyuk wrote:
>>> + /* We need to drop the replay_lock so any vCPU threads woken up
>>> + * can finish their replay tasks
>>> + */
>>> + if (replay_mode != REPLAY_MODE_NONE) {
>>> + g_assert(replay_mutex_locked());
>>> + qemu_mutex_unlock_iothread();
>>> + replay_mutex_unlock();
>>> + qemu_mutex_lock_iothread();
>>> + }
>>
>> The assert+unlock+lock here is unnecessary; just do
>>
>> if (replay_mode != REPLAY_MODE_NONE) {
>> replay_mutex_unlock();
>> }
>>
>> which according to a previous suggestion can become just
>>
>> replay_mutex_unlock();
>
> We can't remove qemu_mutex_unlock_iothread(), because there is an assert
> inside replay_mutex_unlock(), which checks that iothread is unlocked.
I think the assert is wrong. Lock hierarchy only applies to lock, not
unlock.
Paolo
>>
>>> while (!all_vcpus_paused()) {
>>> qemu_cond_wait(&qemu_pause_cond, &qemu_global_mutex);
>>> CPU_FOREACH(cpu) {
>>> qemu_cpu_kick(cpu);
>>> }
>>> }
>>> +
>>> + if (replay_mode != REPLAY_MODE_NONE) {
>>> + qemu_mutex_unlock_iothread();
>>> + replay_mutex_lock();
>>> + qemu_mutex_lock_iothread();
>>> + }
>>
>
> Pavel Dovgalyuk
>
