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Date: Mon, 22 Aug 2011 19:18:39 +0300
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Subject: Re: [Qemu-devel] [RESEND][PATCH] Replace qemu_system_cond with VCPU
 stop mechanism
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel <qemu-devel@nongnu.org>, Gleb Natapov <gleb@redhat.com>

On 08/22/2011 06:46 PM, Jan Kiszka wrote:
> We can express the VCPU thread wakeup with the stop mechanism, saving
> both qemu_system_ready and the qemu_system_cond. For KVM threads, we can
> just enter the main loop as long as the thread is stopped. The central
> TCG thread is better held back before the loop as there can be side
> effects of the services called even when all CPUs are stopped.
>
> Creating VCPUs in stopped state will also be required for proper CPU
> hotplugging support.
>
>
> -    /* and wait for machine initialization */
> -    while (!qemu_system_ready) {
> -        qemu_cond_wait(&qemu_system_cond,&qemu_global_mutex);
> +    /* wait for initial kick-off after machine start */
> +    while (!first_cpu->stopped) {
> +        qemu_cond_wait(tcg_halt_cond,&qemu_global_mutex);
>       }

Seems inverted - do we want to wait until first_cpu is stopped, or while 
first_cpu is stopped?

Do we want to process run_on_cpu() events after the machine is created 
but before a cpu is started (if starting with -S)?

-- 
error compiling committee.c: too many arguments to function