On 2020-08-28 00:19, Daejun Park wrote:
> +static unsigned int ufshpb_host_map_kbytes = 1024;
A comment that explains where this value comes from would be welcome.
> +static struct ufshpb_req *ufshpb_get_map_req(struct ufshpb_lu *hpb,
> + struct ufshpb_subregion *srgn)
> +{
> + struct ufshpb_req *map_req;
> + struct request *req;
> + struct bio *bio;
> +
> + map_req = kmem_cache_alloc(hpb->map_req_cache, GFP_KERNEL);
> + if (!map_req)
> + return NULL;
> +
> + req = blk_get_request(hpb->sdev_ufs_lu->request_queue,
> + REQ_OP_SCSI_IN, BLK_MQ_REQ_PREEMPT);
Why BLK_MQ_REQ_PREEMPT? Since this code is only executed while medium access
commands are processed and since none of these commands have the PREEMPT flag
set I think that the PREEMPT flag should be left out. Otherwise there probably
will be weird interactions with runtime suspended devices.
Is it acceptable that the above blk_get_request() call blocks if a UFS device
has been runtime suspended? If not, consider using the flag BLK_MQ_REQ_NOWAIT
instead.
> + bio = bio_alloc(GFP_KERNEL, hpb->pages_per_srgn);
> + if (!bio) {
> + blk_put_request(req);
> + goto free_map_req;
> + }
If the blk_get_request() would be modified such that it doesn't wait, this
call may have to be modified too (GFP_NOWAIT?).
> + if (rgn->rgn_state == HPB_RGN_INACTIVE) {
> + if (atomic_read(&lru_info->active_cnt)
> + == lru_info->max_lru_active_cnt) {
When splitting a line, please put comparison operators at the end of the line
instead of at the start, e.g. as follows:
if (atomic_read(&lru_info->active_cnt) ==
lru_info->max_lru_active_cnt) {
> + pool_size = DIV_ROUND_UP(ufshpb_host_map_kbytes * 1024, PAGE_SIZE);
Please use PAGE_ALIGN() to align to the next page boundary.
Thanks,
Bart.
