On 12/29/23 15:56, David Laight wrote:
osq_wait_next() is passed 'prev' from osq_lock() and NULL from osq_unlock() but only needs the 'cpu' value to write to lock->tail. Just pass prev->cpu or OSQ_UNLOCKED_VAL instead. Also directly return NULL or 'next' instead of breaking the loop. Should have no effect on the generated code since gcc manages to assume that 'prev != NULL' due to an earlier dereference. Signed-off-by: David Laight <david.laight@xxxxxxxxxx> --- kernel/locking/osq_lock.c | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c index 55f5db896c02..9bb3a077ba92 100644 --- a/kernel/locking/osq_lock.c +++ b/kernel/locking/osq_lock.c @@ -48,18 +48,17 @@ static inline struct optimistic_spin_node *decode_cpu(int encoded_cpu_val) static inline struct optimistic_spin_node * osq_wait_next(struct optimistic_spin_queue *lock, struct optimistic_spin_node *node, - struct optimistic_spin_node *prev) + int old)
Make the last argument name more descriptive, like "old_cpu" as the "int" type does not provide enough context to allow people to guess what "old" may be.
Cheers, Longman
