Re: [Qemu-devel] [RFC PATCH v8 08/21] cpu: replay instructions sequence

["Pavel Dovgaluk" <Pavel.Dovgaluk@ispras.ru>]

> From: Paolo Bonzini [mailto:pbonzini@redhat.com]
> On 22/01/2015 09:52, Pavel Dovgalyuk wrote:
> > This patch adds calls to replay functions into the icount setup block.
> > In record mode number of executed instructions is written to the log.
> > In replay mode number of istructions to execute is taken from the replay log.
> >
> > Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
> > ---
> >  cpu-exec.c      |    1 +
> >  cpus.c          |   28 ++++++++++++++++++----------
> >  replay/replay.c |   24 ++++++++++++++++++++++++
> >  replay/replay.h |    4 ++++
> >  4 files changed, 47 insertions(+), 10 deletions(-)
> >
> > diff --git a/cpu-exec.c b/cpu-exec.c
> > index 49f01f5..99a0993 100644
> > --- a/cpu-exec.c
> > +++ b/cpu-exec.c
> > @@ -531,6 +531,7 @@ int cpu_exec(CPUArchState *env)
> >                              }
> >                              cpu->exception_index = EXCP_INTERRUPT;
> >                              next_tb = 0;
> > +                            qemu_notify_event();
> 
> Why is this needed?

It is needed to wake up iothread in replay mode.
Otherwise it waits for additional time and replay becomes too slow.

> 
> >                              cpu_loop_exit(cpu);
> >                          }
> >                          break;

Pavel Dovgalyuk