From: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
commit 3c5d61ae919cc377c71118ccc76fa6e8518023f8 upstream.
Improve readability of kvfree_rcu_queue_batch() function
in away that, after a first batch queuing, the loop is break
and success value is returned to a caller.
There is no reason to loop and check batches further as all
outstanding objects have already been picked and attached to
a certain batch to complete an offloading.
Fixes: 2b55d6a42d14 ("rcu/kvfree: Add kvfree_rcu_barrier() API")
Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/lkml/ZvWUt2oyXRsvJRNc@pc636/T/
Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3627,11 +3627,12 @@ kvfree_rcu_queue_batch(struct kfree_rcu_
}
// One work is per one batch, so there are three
- // "free channels", the batch can handle. It can
- // be that the work is in the pending state when
- // channels have been detached following by each
- // other.
+ // "free channels", the batch can handle. Break
+ // the loop since it is done with this CPU thus
+ // queuing an RCU work is _always_ success here.
queued = queue_rcu_work(system_wq, &krwp->rcu_work);
+ WARN_ON_ONCE(!queued);
+ break;
}
}
Patches currently in stable-queue which might be from urezki@xxxxxxxxx are
queue-6.11/rcu-kvfree-refactor-kvfree_rcu_queue_batch.patch
queue-6.11/rcu-kvfree-add-kvfree_rcu_barrier-api.patch
queue-6.11/lib-alloc_tag_module_unload-must-wait-for-pending-kfree_rcu-calls.patch
