[Linux-kernel-mentees] [PATCH 1/3] infiniband: hw: hfi1: verbs.c: Use built-in RCU list checking

[Jason Gunthorpe]

On Tue, Jan 07, 2020 at 11:05:08PM +0530, madhuparnabhowmik04 at gmail.com wrote:
> From: Madhuparna Bhowmik <madhuparnabhowmik04 at gmail.com>
> 
> list_for_each_entry_rcu has built-in RCU and lock checking.
> Pass cond argument to list_for_each_entry_rcu.
> 
> Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik04 at gmail.com>
>  drivers/infiniband/hw/hfi1/verbs.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/infiniband/hw/hfi1/verbs.c b/drivers/infiniband/hw/hfi1/verbs.c
> index 089e201d7550..cab2ff185240 100644
> +++ b/drivers/infiniband/hw/hfi1/verbs.c
> @@ -515,7 +515,8 @@ static inline void hfi1_handle_packet(struct hfi1_packet *packet,
>  				       opa_get_lid(packet->dlid, 9B));
>  		if (!mcast)
>  			goto drop;
> -		list_for_each_entry_rcu(p, &mcast->qp_list, list) {
> +		list_for_each_entry_rcu(p, &mcast->qp_list, list
> +								lock_is_held(&(ibp->rvp.lock).dep_map)) {

This is missing a ',' and isn't indented properly. Does it even
compile?

The idea seems sound though.

Jason