On Tue, May 30, 2023 at 02:51:27PM +0000, Alan Huang wrote:
> There is no concurrent updates to 'total' by other threads, plain access
> is enough. But there might be threads updating 'counter', READ_ONCE is
> required.
>
> Signed-off-by: Alan Huang <mmpgouride@xxxxxxxxx>
Queued and pushed, thank you!
Thanx, Paul
> ---
> CodeSamples/count/count_end_rcu.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/CodeSamples/count/count_end_rcu.c b/CodeSamples/count/count_end_rcu.c
> index 8fc70611..71bd5269 100644
> --- a/CodeSamples/count/count_end_rcu.c
> +++ b/CodeSamples/count/count_end_rcu.c
> @@ -48,10 +48,10 @@ unsigned long read_count(void) //\lnlbl{read:b}
>
> rcu_read_lock(); //\lnlbl{read:rrl}
> cap = rcu_dereference(countarrayp); //\lnlbl{read:deref}
> - sum = READ_ONCE(cap->total); //\lnlbl{read:init}
> + sum = cap->total; //\lnlbl{read:init}
> for_each_thread(t) { //\lnlbl{read:add:b}
> ctrp = READ_ONCE(cap->counterp[t]);
> - if (ctrp != NULL) sum += *ctrp; //\lnlbl{read:add:e}
> + if (ctrp != NULL) sum += READ_ONCE(*ctrp); //\lnlbl{read:add:e}
> }
> rcu_read_unlock(); //\lnlbl{read:rru}
> return sum; //\lnlbl{read:ret}
> --
> 2.34.1
>
