Re: [Qemu-devel] [PATCH v2 12/17] translate-all: add page_collection assertions

[Emilio G. Cota]

On Fri, Apr 13, 2018 at 17:42:45 -1000, Richard Henderson wrote:
> On 04/05/2018 04:13 PM, Emilio G. Cota wrote:
> > +static __thread bool page_collection_locked;
> > +
> > +void assert_page_collection_locked(bool val)
> > +{
> > +    tcg_debug_assert(page_collection_locked == val);
> > +}
> > +
> > +static inline void set_page_collection_locked(bool val)
> > +{
> > +    page_collection_locked = val;
> > +}
> > +
> 
> This seems fairly fragile to me.
> 
> (1) Do you ever do assert_page_collection_locked(true)?

No.

> You don't appear to do so, and it's somewhat confusing.

You're right. I think in testing I was using it, but now it
might make more sense to not take any arguments.

> (2) Why does do_page_entry_lock set "locked" and not page_collection_lock?

page_collection_lock calls page_entry_lock and page_trylock_add,
both of which end up calling do_page_entry_lock.

Thanks,

                Emilio