On 11/19/25 16:17, Zhao Liu wrote:
- fn init_timer_with_cell(cell: &BqlRefCell<Self>) {
- let mut timer = cell.borrow_mut();
- // SAFETY: HPETTimer is only used as part of HPETState, which is
- // always pinned.
- let qemu_timer = unsafe { Pin::new_unchecked(&mut timer.qemu_timer) };
- qemu_timer.init_full(None, CLOCK_VIRTUAL, Timer::NS, 0, timer_handler,
cell);
+ fn init_timer(timer: Pin<&mut Self>) {
+ Timer::init_full(
+ timer,
+ None,
+ CLOCK_VIRTUAL,
+ Timer::NS,
+ 0,
+ timer_handler,
+ |t| &mut t.qemu_timer,
+ );
}
I find this way could also work for BqlRefCell case:
fn init_timer_with_cell(cell: &mut BqlRefCell<Self>) {
// SAFETY: HPETTimer is only used as part of HPETState, which is
// always pinned.
let timer = unsafe { Pin::new_unchecked(cell) };
Timer::init_full(
timer,
None,
CLOCK_VIRTUAL,
Timer::NS,
0,
timer_handler,
|t| {
assert!(bql::is_locked());
&mut t.get_mut().qemu_timer
},
);
}
Yes, but I'm still not sure what the final shape will be... I don't like
this too much.
So any other non-lockless timer can also use this interface to
initialize their BqlRefCell<>.
(BTW, I find BqlRefCell::get_mut() / as_ref() missed bql::is_locked().
right?)
as_ptr() doesn't need it because the pointer can be dereferenced later.
As to get_mut()... I think if you are the only owner, you should have
the guarantee of being able to modify the content freely. This is true
even if your &mut came from interior mutability.
So, in the above case you only need &mut t.get_mut().qemu_timer.
I think it may be better to add doc about how to use this for
BqlRefCell<> case since there'll be no example after this patch.
