Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-05-09 Thread Alex Bennée
Paolo Bonzini writes: > On 11/04/2016 22:50, Sergey Fedorov wrote: >>> > +Control multi-threaded TCG. By default QEMU will enable multi-threaded >>> > +emulation for front/back-end combinations that are known to work. The >>> > +user may enable it against the defaults however odd guest behaviour

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-05-09 Thread Paolo Bonzini
On 12/04/2016 16:23, Alex Bennée wrote: > Well one of the reasons I'm keeping single thread behaviour is so things > like icount/replay support can continue to work. The two options will be > incompatible to start with. As long as the single-threaded TCG gets rid of iothread's special behavior o

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-05-09 Thread Paolo Bonzini
On 11/04/2016 22:50, Sergey Fedorov wrote: >> > +Control multi-threaded TCG. By default QEMU will enable multi-threaded >> > +emulation for front/back-end combinations that are known to work. The >> > +user may enable it against the defaults however odd guest behaviour >> > +may occur. >> > +@end

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Alex Bennée
Sergey Fedorov writes: > On 05/04/16 18:32, Alex Bennée wrote: >> diff --git a/cpus.c b/cpus.c >> index 46732a5..8d27fb0 100644 >> --- a/cpus.c >> +++ b/cpus.c > > (snip) > >> @@ -146,6 +147,48 @@ typedef struct TimersState { >> } TimersState; >> >> static TimersState timers_state; >> +static

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Alex Bennée
Pavel Dovgalyuk writes: >> From: mttcg-requ...@listserver.greensocs.com >> [mailto:mttcg-requ...@listserver.greensocs.com] >> On 12/04/16 15:50, KONRAD Frederic wrote: >> >> Yes, but users may like to have an option to disable MTTCG for some >> >> reason. I'm also concerned about icount mode: n

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Sergey Fedorov
On 05/04/16 18:32, Alex Bennée wrote: > diff --git a/cpus.c b/cpus.c > index 46732a5..8d27fb0 100644 > --- a/cpus.c > +++ b/cpus.c (snip) > @@ -146,6 +147,48 @@ typedef struct TimersState { > } TimersState; > > static TimersState timers_state; > +static bool mttcg_enabled; > + > +static QemuO

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Sergey Fedorov
On 12/04/16 16:03, Pavel Dovgalyuk wrote: >> From: mttcg-requ...@listserver.greensocs.com >> [mailto:mttcg-requ...@listserver.greensocs.com] >> On 12/04/16 15:50, KONRAD Frederic wrote: Yes, but users may like to have an option to disable MTTCG for some reason. I'm also concerned about i

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Pavel Dovgalyuk
> From: mttcg-requ...@listserver.greensocs.com > [mailto:mttcg-requ...@listserver.greensocs.com] > On 12/04/16 15:50, KONRAD Frederic wrote: > >> Yes, but users may like to have an option to disable MTTCG for some > >> reason. I'm also concerned about icount mode: not sure how to account > >> virt

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Sergey Fedorov
On 12/04/16 15:50, KONRAD Frederic wrote: > > > Le 12/04/2016 14:42, Sergey Fedorov a écrit : >> On 12/04/16 14:59, Peter Maydell wrote: >>> On 12 April 2016 at 12:48, Alex Bennée wrote: Sergey Fedorov writes: > Maybe we'd better use existing qemu accelerator framework and > introduc

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread KONRAD Frederic
Le 12/04/2016 14:42, Sergey Fedorov a écrit : On 12/04/16 14:59, Peter Maydell wrote: On 12 April 2016 at 12:48, Alex Bennée wrote: Sergey Fedorov writes: Maybe we'd better use existing qemu accelerator framework and introduce "-machine accel=mttcg" option? My worry would be breaking exis

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Sergey Fedorov
On 12/04/16 14:48, Alex Bennée wrote: > Sergey Fedorov writes: > >> On 05/04/16 18:32, Alex Bennée wrote: >>> diff --git a/qemu-options.hx b/qemu-options.hx >>> index a770086..4eca704 100644 >>> --- a/qemu-options.hx >>> +++ b/qemu-options.hx >>> @@ -3224,6 +3224,20 @@ Attach to existing xen domai

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Sergey Fedorov
On 12/04/16 14:59, Peter Maydell wrote: > On 12 April 2016 at 12:48, Alex Bennée wrote: >> Sergey Fedorov writes: >>> Maybe we'd better use existing qemu accelerator framework and introduce >>> "-machine accel=mttcg" option? >> My worry would be breaking existing code which assumes kvm | tcg. We

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Peter Maydell
On 12 April 2016 at 12:48, Alex Bennée wrote: > Sergey Fedorov writes: >> Maybe we'd better use existing qemu accelerator framework and introduce >> "-machine accel=mttcg" option? > > My worry would be breaking existing code which assumes kvm | tcg. We > will want to enable mttcg by default for c

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-12 Thread Alex Bennée
Sergey Fedorov writes: > On 05/04/16 18:32, Alex Bennée wrote: >> diff --git a/qemu-options.hx b/qemu-options.hx >> index a770086..4eca704 100644 >> --- a/qemu-options.hx >> +++ b/qemu-options.hx >> @@ -3224,6 +3224,20 @@ Attach to existing xen domain. >> xend will use this when starting QEMU (

Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-11 Thread Sergey Fedorov
On 05/04/16 18:32, Alex Bennée wrote: > diff --git a/qemu-options.hx b/qemu-options.hx > index a770086..4eca704 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -3224,6 +3224,20 @@ Attach to existing xen domain. > xend will use this when starting QEMU (XEN only). > ETEXI > > +DEF("tc

[Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

2016-04-05 Thread Alex Bennée
From: KONRAD Frederic We know there will be cases where MTTCG won't work until additional work is done in the front/back ends to support. It will however be useful to be able to turn it on. As a result MTTCG will default to off unless the combination is supported. However the user can turn it on