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>>>>>=20 >>>>> to bindings.rs? >>>>>=20 >>>>=20 >>>> This option is currently not maintainable unless it becomes a >>>> maintainer-aware way to handle things like this. >>>>=20 >>>>> (Or even better, changing `#define` to `typedef` so bindgen takes car= e of >>>>> everything). >>>>>=20 >>>>=20 >>>> Yes, this is better IMO, but it's up to slab maintainers. :-) >>> >>> Can you elaborate a bit please, how would that look like? >>=20 >> I was thinking of doing `typedef struct rcu_head kvfree_rcu_head;` but o= f course >> that didn't work because you can't use typedef to create `kvfree_rcu_hea= d` :) >>=20 >> However, something like this could work? >>=20 >> #ifdef CONFIG_KVFREE_RCU_BATCHED >> ... >> #else >> struct kvfree_rcu_head { >> struct rcu_head head; >> }; >> #endif >>=20 >> and everywhere add a cast everywhere that expects kvfree_rcu_head =3D=3D= rcu_head. >>=20 >> but this would indeed be more complex :( > > So you mean like this? Doesn't seem so complex and seems to compile here > with CONFIG_KVFREE_RCU_BATCHED both disabled and enabled. I thought that a lot more places have to be updated, but it looks from your= diff below that this is simple enough. Best, Gary > I can apply the slab part in slab tree, but AFAICS the poll.rs > change still needs to be done in the merge commit. Unless there's > some way to make things conditional on whether kvfree_rcu_head exists? > > diff --git a/include/linux/types.h b/include/linux/types.h > index 79bf419c69e4..53e0adca4b9f 100644 > --- a/include/linux/types.h > +++ b/include/linux/types.h > @@ -262,7 +262,9 @@ struct kvfree_rcu_head { > struct kvfree_rcu_head *next; > }; > #else > -#define kvfree_rcu_head rcu_head > +struct kvfree_rcu_head { > + struct rcu_head head; > +}; > #endif > =20 > typedef void (*rcu_callback_t)(struct rcu_head *head); > diff --git a/mm/slab_common.c b/mm/slab_common.c > index 64845ac81b79..aecbe9b9df4c 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -1325,11 +1325,11 @@ EXPORT_SYMBOL_GPL(kfree_call_rcu_nolock); > =20 > #ifndef CONFIG_KVFREE_RCU_BATCHED > =20 > -void kvfree_call_rcu(struct rcu_head *head, void *ptr) > +void kvfree_call_rcu(struct kvfree_rcu_head *head, void *ptr) > { > if (head) { > kasan_record_aux_stack(ptr); > - call_rcu(head, kvfree_rcu_cb); > + call_rcu(&head->head, kvfree_rcu_cb); > return; > } > =20 > diff --git a/rust/kernel/sync/poll.rs b/rust/kernel/sync/poll.rs > index 684dfa242b1a..f3cdf95db12d 100644 > --- a/rust/kernel/sync/poll.rs > +++ b/rust/kernel/sync/poll.rs > @@ -124,7 +124,7 @@ pub struct PollCondVarBox { > struct PollCondVarBoxInner { > #[pin] > inner: PollCondVar, > - rcu: Opaque, > + rcu: Opaque, > } > =20 > // SAFETY: PollCondVar is Send