Hi Damien, On 1/22/21 11:36 AM, Damien Hedde wrote: > Move the reset count decrement from "just after" to "just before" > calling the exit phase handler. The goal is to make > resettable_is_in_reset() returning false during the handler execution. > > This simplifies reset handling in resettable devices. > > Typically, a function that updates the device state will just need > to read the current reset state and not anymore treat the "in > a reset-exit transition" special case. > > As a side note, this patch also fixes the fact that the reset count was > not decremented in case of recursive reset. > > Signed-off-by: Damien Hedde <[email protected]> > Buglink: https://bugs.launchpad.net/qemu/+bug/1905297 > Reported-by: Michael Peter <[email protected]> > -- > > Hi, > > Following our discussion: > https://lists.nongnu.org/archive/html/qemu-devel/2021-01/msg01013.html > here's my proposal to fix Michael's bug on a global scope. > > I flaged it v2 because I've taken Philippe's remarks there: > https://lists.nongnu.org/archive/html/qemu-devel/2020-12/msg00635.html > I've also changed the patch title, I think it is better this way. > > Thanks, > Damien > > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > --- > docs/devel/reset.rst | 6 +++--- > hw/core/resettable.c | 3 +-- > 2 files changed, 4 insertions(+), 5 deletions(-) > > diff --git a/docs/devel/reset.rst b/docs/devel/reset.rst > index abea1102dc..021a7277a2 100644 > --- a/docs/devel/reset.rst > +++ b/docs/devel/reset.rst > @@ -210,9 +210,9 @@ Polling the reset state > Resettable interface provides the ``resettable_is_in_reset()`` function. > This function returns true if the object parameter is currently under reset. > > -An object is under reset from the beginning of the *init* phase to the end of > -the *exit* phase. During all three phases, the function will return that the > -object is in reset. > +An object is under reset from the beginning of the *init* phase to the *exit* > +phase. During *init* and *hold* phase only, the function will return that the > +object is in reset. The state is changed just before calling the *exit* > method.
"An object is under reset from the beginning of the *init* phase to the beginning of the *exit* phase" ? An ASCII art would clarify all doubts :) Otherwise: Reviewed-by: Philippe Mathieu-Daudé <[email protected]> > > This function may be used if the object behavior has to be adapted > while in reset state. For example if a device has an irq input, > diff --git a/hw/core/resettable.c b/hw/core/resettable.c > index 96a99ce39e..c3df75c6ba 100644 > --- a/hw/core/resettable.c > +++ b/hw/core/resettable.c > @@ -201,12 +201,11 @@ static void resettable_phase_exit(Object *obj, void > *opaque, ResetType type) > resettable_child_foreach(rc, obj, resettable_phase_exit, NULL, type); > > assert(s->count > 0); > - if (s->count == 1) { > + if (--s->count == 0) { > trace_resettable_phase_exit_exec(obj, obj_typename, > !!rc->phases.exit); > if (rc->phases.exit && !resettable_get_tr_func(rc, obj)) { > rc->phases.exit(obj); > } > - s->count = 0; > } > s->exit_phase_in_progress = false; > trace_resettable_phase_exit_end(obj, obj_typename, s->count); >
