Re: [Qemu-stable] [PATCH for-2.12] cpus.c: ensure running CPU recalculates icount deadlines on timer expiry

[Peter Maydell]

On 6 April 2018 at 13:58, Alex Bennée <address@hidden> wrote:
>
> Peter Maydell <address@hidden> writes:
>> -    if (!qemu_in_vcpu_thread() && first_cpu) {
>> +    if (qemu_in_vcpu_thread()) {
>> +        /* A CPU is currently running; kick it back out to the
>> +         * tcg_cpu_exec() loop so it will recalculate its
>> +         * icount deadline immediately.
>> +         */
>> +        qemu_cpu_kick(current_cpu);
>
> This is only totally true if whatever has caused the re-calculation has
> ended the Translation Block, otherwise we won't finish until we've run a
> few more instructions.

That should always be true, because it will be an IO instruction,
which we enforce is always the last insn in a TB.

thanks
-- PMM