On 05/30/2018 09:45 AM, Christoph Hellwig wrote:
> Just keep a per-controller buffer of changed namespaces and copy it out
> in the get log page implementation.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
[...]
> +static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
> +{
> + mutex_lock(&ctrl->lock);
> + if (ctrl->nr_changed_ns < NVME_MAX_CHANGED_NAMESPACES) {
Minor nitpick here: if ctrlr->nr_changed_ns is exactly
NVME_MAX_CHANGED_NAMESPACES and the new nsid is already in the list,
this will skip down to the 0xffffffff case below, even though it could
have just left the list as-is.
I don't know if this is a problem in practice; reporting 0xffffffff is
probably always safe, since the host will presumably treat that as
"rescan everything".
> + u32 i;
> +
> + for (i = 0; i < ctrl->nr_changed_ns; i++)
> + if (ctrl->changed_ns_list[i] == nsid)
> + goto out_unlock;
> + ctrl->changed_ns_list[ctrl->nr_changed_ns++] = nsid;
> + } else if (ctrl->nr_changed_ns == NVME_MAX_CHANGED_NAMESPACES) {
> + ctrl->changed_ns_list[0] = cpu_to_le32(0xffffffff);
> + ctrl->nr_changed_ns = U32_MAX;
> + }
> +out_unlock:
> + mutex_unlock(&ctrl->lock);
> +}
Thanks,
-- Daniel
