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. 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); -- 2.29.2
