Re: [PATCH 4/5] add single_task_running

[Paolo Bonzini <pbonzini@redhat.com>]

On 10/02/2015 17:46, Jan Kiszka wrote:
>> > +#if LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0)
>> > +bool single_task_running(void)
>> > +{
>> > +	/* Not exactly the same... */
>> > +	return !need_resched();
>> > +}
>> > +#endif
>> > 
> 3.15 and earlier lacks ktime_before in addition, see e.g.
> http://buildbot.kiszka.org/kvm-kmod/builders/3-next/builds/395/steps/3.15-x86-64/logs/stdio

Ah... indeed I tested with 3.16 (that's what I usually use when I'm not
compiling the whole kernel, because RHEL7.1's KVM is based on 3.16).

> I'm not yet sure where to cut backward support now, maybe 3.10 (LTS).

Yeah, either 3.2 or 3.10 I guess.  (Is Debian still using 3.2?)

> 3.9 gives a strange warning in __do_insn_fetch_bytes though the involved
> code should be identical to building for newer kernels:
> 
> http://buildbot.kiszka.org/kvm-kmod/builders/3-next/builds/395/steps/3.9-x86-64/logs/stdio

Weird...

Paolo