RE: [[PATCH v1] 19/37] [CIFS] SMBD: Manage credits on SMBD client and server

[Tom Talpey]

> -----Original Message-----
> From: linux-cifs-owner@xxxxxxxxxxxxxxx [mailto:linux-cifs-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Long Li
> Sent: Wednesday, August 2, 2017 4:11 PM
> To: Steve French <sfrench@xxxxxxxxx>; linux-cifs@xxxxxxxxxxxxxxx; samba-
> technical@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Cc: Long Li <longli@xxxxxxxxxxxxx>
> Subject: [[PATCH v1] 19/37] [CIFS] SMBD: Manage credits on SMBD client and
> server
> 
>  /*
> + * Extend the credits to remote peer
> + * This implements [MS-SMBD] 3.1.5.9
> + * The idea is that we should extend credits to remote peer as quickly as
> + * it's allowed, to maintain data flow. We allocate as much as receive
> + * buffer as possible, and extend the receive credits to remote peer
> + * return value: the new credtis being granted.
> + */
> +static int manage_credits_prior_sending(struct cifs_rdma_info *info)
> +{
> +       int ret = 0;
> +       struct cifs_rdma_response *response;
> +       int rc;
> +
> +       if (atomic_read(&info->receive_credit_target) >

When does the receive_credit_target value change? It seems wasteful to
perform an atomic_read() on this local value each time.

Tom.