Re: [PATCH v3 next 1/5] Only clear node->locked in the slow osq_lock() path

[David Laight]

On Fri,  6 Mar 2026 22:51:46 +0000
david.laight.linux@xxxxxxxxx wrote:

Apologies to Yafang for mistyping his address...

> From: David Laight <david.laight.linux@xxxxxxxxx>
> 
> node->locked is used to indicate that the owner of the lock has handed it
> off to the waiting CPU.
> As such it's value is only relevant in the slow path so it need not be
> initialised in the fast path.
> 
> Signed-off-by: David Laight <david.laight.linux@xxxxxxxxx>
> ---
>  kernel/locking/osq_lock.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c
> index b4233dc2c2b0..96c6094157b5 100644
> --- a/kernel/locking/osq_lock.c
> +++ b/kernel/locking/osq_lock.c
> @@ -97,7 +97,6 @@ bool osq_lock(struct optimistic_spin_queue *lock)
>  	int curr = encode_cpu(smp_processor_id());
>  	int old;
>  
> -	node->locked = 0;
>  	node->next = NULL;
>  	node->cpu = curr;
>  
> @@ -113,6 +112,7 @@ bool osq_lock(struct optimistic_spin_queue *lock)
>  
>  	prev = decode_cpu(old);
>  	node->prev = prev;
> +	node->locked = 0;
>  
>  	/*
>  	 * osq_lock()			unqueue