Re: [PATCH 3/3] accel/tcg: Make TCGCPUOps::cpu_exec_halt mandatory

On Tue, 18 Aug 2026 at 14:35, Philippe Mathieu-Daudé
<[email protected]> wrote:
>
> On 3/6/24 18:09, Peter Maydell wrote:
> > Now that all targets set TCGCPUOps::cpu_exec_halt, we can make it
> > mandatory and remove the fallback handling that calls cpu_has_work.
> >
> > Signed-off-by: Peter Maydell <[email protected]>

> >        * Return true to indicate that the CPU should now leave halt, false
> > -     * if it should remain in the halted state.
> > +     * if it should remain in the halted state. (This should generally
> > +     * be the same value that cpu_has_work() would return.)
> >        *
> > -     * If this method is not provided, the default is to do nothing, and
> > -     * to leave halt if cpu_has_work() returns true.
> > +     * This method must be provided. If the target does not need to
> > +     * do anything special for halt, the same function used for its
> > +     * CPUClass::has_work method can be used here, as they have the
> > +     * same function signature.
>
> With retrospective, has_work() should be idempotent, taking a const
> CPUState, while cpu_exec_halt() is expected to change CPUState
> internal fields.

Mmm; we added the "should be idempotent" comment to the has_work docs
in include/hw/core/sysemu-cpu-ops.h, but it still takes a plain CPUState*.
Constifying wouldn't be trivial because e.g. cpu_env() and cpu_test_interrupt()
and so on take a non-const pointer.

-- PMM