Re: [PATCH v1 4/6] rcu: rename __is_kfree_rcu_offset() macro

From: Joel Fernandes
Date: Mon Mar 16 2020 - 11:48:54 EST


On Sun, Mar 15, 2020 at 07:18:38PM +0100, Uladzislau Rezki (Sony) wrote:
> Rename __is_kfree_rcu_offset to __is_kvfree_rcu_offset.
> All RCU paths use kvfree() now instead of kfree(), thus
> rename it.

This patch LGTM:
Reviewed-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>

thanks,

- Joel
>
> Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> ---
> include/linux/rcupdate.h | 6 +++---
> kernel/rcu/tiny.c | 2 +-
> kernel/rcu/tree.c | 4 ++--
> 3 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
> index bb270221dbdc..e4961631a44f 100644
> --- a/include/linux/rcupdate.h
> +++ b/include/linux/rcupdate.h
> @@ -798,16 +798,16 @@ static inline notrace void rcu_read_unlock_sched_notrace(void)
>
> /*
> * Does the specified offset indicate that the corresponding rcu_head
> - * structure can be handled by kfree_rcu()?
> + * structure can be handled by kvfree_rcu()?
> */
> -#define __is_kfree_rcu_offset(offset) ((offset) < 4096)
> +#define __is_kvfree_rcu_offset(offset) ((offset) < 4096)
>
> /*
> * Helper macro for kfree_rcu() to prevent argument-expansion eyestrain.
> */
> #define __kfree_rcu(head, offset) \
> do { \
> - BUILD_BUG_ON(!__is_kfree_rcu_offset(offset)); \
> + BUILD_BUG_ON(!__is_kvfree_rcu_offset(offset)); \
> kfree_call_rcu(head, (rcu_callback_t)(unsigned long)(offset)); \
> } while (0)
>
> diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
> index 3dd8e6e207b0..aa897c3f2e92 100644
> --- a/kernel/rcu/tiny.c
> +++ b/kernel/rcu/tiny.c
> @@ -85,7 +85,7 @@ static inline bool rcu_reclaim_tiny(struct rcu_head *head)
> unsigned long offset = (unsigned long)head->func;
>
> rcu_lock_acquire(&rcu_callback_map);
> - if (__is_kfree_rcu_offset(offset)) {
> + if (__is_kvfree_rcu_offset(offset)) {
> trace_rcu_invoke_kvfree_callback("", head, offset);
> kvfree((void *)head - offset);
> rcu_lock_release(&rcu_callback_map);
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index eef75cd210fd..bb9544238396 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -2719,7 +2719,7 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func)
> return; // Enqueued onto ->nocb_bypass, so just leave.
> // If no-CBs CPU gets here, rcu_nocb_try_bypass() acquired ->nocb_lock.
> rcu_segcblist_enqueue(&rdp->cblist, head);
> - if (__is_kfree_rcu_offset((unsigned long)func))
> + if (__is_kvfree_rcu_offset((unsigned long)func))
> trace_rcu_kvfree_callback(rcu_state.name, head,
> (unsigned long)func,
> rcu_segcblist_n_cbs(&rdp->cblist));
> @@ -2911,7 +2911,7 @@ static void kfree_rcu_work(struct work_struct *work)
> rcu_lock_acquire(&rcu_callback_map);
> trace_rcu_invoke_kvfree_callback(rcu_state.name, head, offset);
>
> - if (!WARN_ON_ONCE(!__is_kfree_rcu_offset(offset)))
> + if (!WARN_ON_ONCE(!__is_kvfree_rcu_offset(offset)))
> kvfree((void *)head - offset);
>
> rcu_lock_release(&rcu_callback_map);
> --
> 2.20.1
>