On 2021-03-15 09:31, Daejun Park wrote:
This patch supports the HPB 2.0.
The HPB 2.0 supports read of varying sizes from 4KB to 512KB.
In the case of Read (<= 32KB) is supported as single HPB read.
In the case of Read (36KB ~ 512KB) is supported by as a combination of
write buffer command and HPB read command to deliver more PPN.
The write buffer commands may not be issued immediately due to busy
tags.
To use HPB read more aggressively, the driver can requeue the write
buffer
command. The requeue threshold is implemented as timeout and can be
modified with requeue_timeout_ms entry in sysfs.
Signed-off-by: Daejun Park <daejun7.park@xxxxxxxxxxx>
---
+static struct attribute *hpb_dev_param_attrs[] = {
+ &dev_attr_requeue_timeout_ms.attr,
+ NULL,
+};
+
+struct attribute_group ufs_sysfs_hpb_param_group = {
+ .name = "hpb_param_sysfs",
+ .attrs = hpb_dev_param_attrs,
+};
+
+static int ufshpb_pre_req_mempool_init(struct ufshpb_lu *hpb)
+{
+ struct ufshpb_req *pre_req = NULL;
+ int qd = hpb->sdev_ufs_lu->queue_depth / 2;
+ int i, j;
+
+ INIT_LIST_HEAD(&hpb->lh_pre_req_free);
+
+ hpb->pre_req = kcalloc(qd, sizeof(struct ufshpb_req), GFP_KERNEL);
+ hpb->throttle_pre_req = qd;
+ hpb->num_inflight_pre_req = 0;
+
+ if (!hpb->pre_req)
+ goto release_mem;
+
+ for (i = 0; i < qd; i++) {
+ pre_req = hpb->pre_req + i;
+ INIT_LIST_HEAD(&pre_req->list_req);
+ pre_req->req = NULL;
+ pre_req->bio = NULL;
Why don't prepare bio as same as wb.m_page? Won't that save more time
for ufshpb_issue_pre_req()?
Thanks,
Can Guo.
+
+ pre_req->wb.m_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!pre_req->wb.m_page) {
+ for (j = 0; j < i; j++)
+ __free_page(hpb->pre_req[j].wb.m_page);
+
+ goto release_mem;
+ }
+ list_add_tail(&pre_req->list_req, &hpb->lh_pre_req_free);
+ }
+
+ return 0;
+release_mem:
+ kfree(hpb->pre_req);
+ return -ENOMEM;
+}
+
