v2 -> v3:
- Attend Greg's and Can's comments
- rebase on Daejun's v21
v1 -> v2:
- attend Greg's and Daejun's comments
- add patch 9 making host mode parameters configurable
- rebase on Daejun's v19
The HPB spec defines 2 control modes - device control mode and host
control mode. In oppose to device control mode, in which the host obey
to whatever recommendation received from the device - In host control
mode, the host uses its own algorithms to decide which regions should
be activated or inactivated.
We kept the host managed heuristic simple and concise.
Aside from adding a by-spec functionality, host control mode entails
some further potential benefits: makes the hpb logic transparent and
readable, while allow tuning / scaling its various parameters, and
utilize system-wide info to optimize HPB potential.
This series is based on Samsung's V19 device-control HPB2.0 driver, see
msg-id: 20210218090853epcms2p8ccac0b5611dec22afd04ecc06e74498e@epcms2p8
in lore.kernel.org. The patches are also available in wdc ufs repo:
https://github.com/westerndigitalcorporation/WDC-UFS-REPO/tree/hpb-v21
This version was tested on Galaxy S20, and Xiaomi Mi10 pro.
Your meticulous review and testing is mostly welcome and appreciated.
Thanks,
Avri
Avri Altman (9):
scsi: ufshpb: Cache HPB Control mode on init
scsi: ufshpb: Add host control mode support to rsp_upiu
scsi: ufshpb: Add region's reads counter
scsi: ufshpb: Make eviction depends on region's reads
scsi: ufshpb: Region inactivation in host mode
scsi: ufshpb: Add hpb dev reset response
scsi: ufshpb: Add "Cold" regions timer
scsi: ufshpb: Add support for host control mode
scsi: ufshpb: Make host mode parameters configurable
Documentation/ABI/testing/sysfs-driver-ufs | 68 +++
drivers/scsi/ufs/ufshcd.h | 2 +
drivers/scsi/ufs/ufshpb.c | 622 +++++++++++++++++++--
drivers/scsi/ufs/ufshpb.h | 44 +-
4 files changed, 691 insertions(+), 45 deletions(-)
--
2.25.1
In device control mode, the device may recommend the host to either
activate or inactivate a region, and the host should follow. Meaning
those are not actually recommendations, but more of instructions.
On the contrary, in host control mode, the recommendation protocol is
slightly changed:
a) The device may only recommend the host to update a subregion of an
already-active region. And,
b) The device may *not* recommend to inactivate a region.
Furthermore, in host control mode, the host may choose not to follow any
of the device's recommendations. However, in case of a recommendation to
update an active and clean subregion, it is better to follow those
recommendation because otherwise the host has no other way to know that
some internal relocation took place.
Signed-off-by: Avri Altman <[email protected]>
---
drivers/scsi/ufs/ufshpb.c | 34 +++++++++++++++++++++++++++++++++-
drivers/scsi/ufs/ufshpb.h | 2 ++
2 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index f9140f3a4eed..e052260868ad 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -156,6 +156,8 @@ static void ufshpb_set_ppn_dirty(struct ufshpb_lu *hpb, int rgn_idx,
else
set_bit_len = cnt;
+ set_bit(RGN_FLAG_DIRTY, &rgn->rgn_flags);
+
if (rgn->rgn_state != HPB_RGN_INACTIVE &&
srgn->srgn_state == HPB_SRGN_VALID)
bitmap_set(srgn->mctx->ppn_dirty, srgn_offset, set_bit_len);
@@ -222,6 +224,11 @@ static bool ufshpb_test_ppn_dirty(struct ufshpb_lu *hpb, int rgn_idx,
return false;
}
+static inline bool is_rgn_dirty(struct ufshpb_region *rgn)
+{
+ return test_bit(RGN_FLAG_DIRTY, &rgn->rgn_flags);
+}
+
static int ufshpb_fill_ppn_from_page(struct ufshpb_lu *hpb,
struct ufshpb_map_ctx *mctx, int pos, int len,
u64 *ppn_buf)
@@ -715,6 +722,7 @@ static void ufshpb_put_map_req(struct ufshpb_lu *hpb,
static int ufshpb_clear_dirty_bitmap(struct ufshpb_lu *hpb,
struct ufshpb_subregion *srgn)
{
+ struct ufshpb_region *rgn;
u32 num_entries = hpb->entries_per_srgn;
WARN_ON(!srgn->mctx);
@@ -723,6 +731,10 @@ static int ufshpb_clear_dirty_bitmap(struct ufshpb_lu *hpb,
num_entries = hpb->last_srgn_entries;
bitmap_zero(srgn->mctx->ppn_dirty, num_entries);
+
+ rgn = hpb->rgn_tbl + srgn->rgn_idx;
+ clear_bit(RGN_FLAG_DIRTY, &rgn->rgn_flags);
+
return 0;
}
@@ -1171,6 +1183,18 @@ static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
srgn_i =
be16_to_cpu(rsp_field->hpb_active_field[i].active_srgn);
+ rgn = hpb->rgn_tbl + rgn_i;
+ if (hpb->is_hcm &&
+ (rgn->rgn_state != HPB_RGN_ACTIVE || is_rgn_dirty(rgn))) {
+ /*
+ * in host control mode, subregion activation
+ * recommendations are only allowed to active regions.
+ * Also, ignore recommendations for dirty regions - the
+ * host will make decisions concerning those by himself
+ */
+ continue;
+ }
+
dev_dbg(&hpb->sdev_ufs_lu->sdev_dev,
"activate(%d) region %d - %d\n", i, rgn_i, srgn_i);
@@ -1178,7 +1202,6 @@ static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
ufshpb_update_active_info(hpb, rgn_i, srgn_i);
spin_unlock(&hpb->rsp_list_lock);
- rgn = hpb->rgn_tbl + rgn_i;
srgn = rgn->srgn_tbl + srgn_i;
/* blocking HPB_READ */
@@ -1189,6 +1212,14 @@ static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
hpb->stats.rb_active_cnt++;
}
+ if (hpb->is_hcm) {
+ /*
+ * in host control mode the device is not allowed to inactivate
+ * regions
+ */
+ goto out;
+ }
+
for (i = 0; i < rsp_field->inactive_rgn_cnt; i++) {
rgn_i = be16_to_cpu(rsp_field->hpb_inactive_field[i]);
dev_dbg(&hpb->sdev_ufs_lu->sdev_dev,
@@ -1213,6 +1244,7 @@ static void ufshpb_rsp_req_region_update(struct ufshpb_lu *hpb,
hpb->stats.rb_inactive_cnt++;
}
+out:
dev_dbg(&hpb->sdev_ufs_lu->sdev_dev, "Noti: #ACT %u #INACT %u\n",
rsp_field->active_rgn_cnt, rsp_field->inactive_rgn_cnt);
diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
index f55a71b250eb..8e6c2a5b80a0 100644
--- a/drivers/scsi/ufs/ufshpb.h
+++ b/drivers/scsi/ufs/ufshpb.h
@@ -115,6 +115,8 @@ struct ufshpb_region {
/* below information is used by lru */
struct list_head list_lru_rgn;
+ unsigned long rgn_flags;
+#define RGN_FLAG_DIRTY 0
};
#define for_each_sub_region(rgn, i, srgn) \
--
2.25.1