Commit Graph

24 Commits

Author SHA1 Message Date
ChanWoo Lee 65ef27f779 scsi: ufs: ufshpb: Remove unused parameters
The following parameters are not used in the function. Remove them.

*func(): ufshpb_set_hpb_read_to_upiu
 -> struct ufshpb_lu *hpb
 -> u32 lpn

Link: https://lore.kernel.org/r/20210901025617.31174-1-cw9316.lee@samsung.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: ChanWoo Lee <cw9316.lee@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-09-13 22:15:42 -04:00
Keoseong Park 922ad26ebe scsi: ufs: ufshpb: Fix typo in comments
Change "allcation" to "allocation".

Link: https://lore.kernel.org/r/1891546521.01629282781634.JavaMail.epsvc@epcpadp4
Signed-off-by: Keoseong Park <keosung.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-24 22:56:33 -04:00
Keoseong Park 6c9783e629 scsi: ufs: ufshpb: Fix possible memory leak
When HPB pinned region exists and mctx allocation for this region fails, a
memory leak is possible because memory is not released for the subregion
table of the current region.

Free memory for the subregion table of the current region.

Link: https://lore.kernel.org/r/1891546521.01629711601304.JavaMail.epsvc@epcpadp3
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Keoseong Park <keosung.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-24 22:56:32 -04:00
Martin K. Petersen 12bc2f13f3 scsi: ufs: ufshpb: Use scsi_cmd_to_rq() instead of scsi_cmnd.request
Prepare for removal of the request pointer by using scsi_cmd_to_rq()
instead. This patch does not change any functionality.

Link: https://lore.kernel.org/r/20210809230355.8186-1-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:42 -04:00
Avri Altman 10163cee1f scsi: ufs: ufshpb: Do not report victim error in HCM
In host control mode, eviction is perceived as an extreme measure. There
are several conditions that both the entering and exiting regions should
meet, so that eviction will take place.

The common case however, is that those conditions are rarely met, so it is
normal that the act of eviction fails.  Therefore, do not report an error
in host control mode if eviction fails.

Link: https://lore.kernel.org/r/20210808090024.21721-5-avri.altman@wdc.com
Fixes: 6c59cb501b (scsi: ufs: ufshpb: Make eviction depend on region's reads)
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:36 -04:00
Avri Altman 22aede9f48 scsi: ufs: ufshpb: Verify that 'num_inflight_map_req' is non-negative
'num_inflight_map_req' should not be negative.  It is incremented and
decremented without any protection, allowing it theoretically to be
negative, should some weird unbalanced count occur.

Verify that the those calls are properly serialized.

Link: https://lore.kernel.org/r/20210808090024.21721-4-avri.altman@wdc.com
Fixes: 33845a2d84 (scsi: ufs: ufshpb: Limit the number of in-flight map requests)
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:36 -04:00
Avri Altman 283e61c5a9 scsi: ufs: ufshpb: Rewind the read timeout on every read
The purpose of the "cold"-timer is not to hang-on to active regions with no
reads.  Therefore the read timeout should be rewound on every read, and not
just when the region is activated.

Link: https://lore.kernel.org/r/20210808090024.21721-2-avri.altman@wdc.com
Fixes: 13c044e916 (scsi: ufs: ufshpb: Add "cold" regions timer)
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:36 -04:00
Bean Huo 63522bf3ac scsi: ufs: core: Add L2P entry swap quirk for Micron UFS
For Micron UFS devices the L2P entry need to be byteswapped before sending
an HPB READ command to the UFS device. Add the quirk
UFS_DEVICE_QUIRK_SWAP_L2P_ENTRY_FOR_HPB_READ to address this.

Link: https://lore.kernel.org/r/20210804182128.458356-2-huobean@gmail.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-05 23:21:08 -04:00
Avri Altman f95f59a2bb scsi: ufs: ufshpb: Make host mode parameters configurable
Elaborate some more on the host control mode logic parameters, explaining
what they do and how to configure them.

Link: https://lore.kernel.org/r/20210712095039.8093-13-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:15 -04:00
Avri Altman 5dea655a09 scsi: ufs: ufshpb: Add support for host control mode
Support devices that report they are using host control mode.

Link: https://lore.kernel.org/r/20210712095039.8093-12-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:15 -04:00
Avri Altman 1afb7ddadc scsi: ufs: ufshpb: Do not send umap_all in host control mode
HPB WRITE BUFFER with buffer-id = 0x3h is supported in device control mode
only.

Link: https://lore.kernel.org/r/20210712095039.8093-11-avri.altman@wdc.com
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:15 -04:00
Avri Altman 33845a2d84 scsi: ufs: ufshpb: Limit the number of in-flight map requests
In host control mode the host is the originator of map requests. To not
flood the device with map requests, use a simple throttling mechanism that
limits the number of in-flight map requests.

Link: https://lore.kernel.org/r/20210712095039.8093-10-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:15 -04:00
Avri Altman 13c044e916 scsi: ufs: ufshpb: Add "cold" regions timer
In order not to hang on to "cold" regions, we inactivate a region that has
had no READ access for a predefined amount of time - READ_TO_MS. For that
purpose monitor the active regions list, polling it on every
POLLING_INTERVAL_MS. On timeout expiry add the region to the
"to-be-inactivated" list unless it is clean and did not exhaust its
READ_TO_EXPIRIES - another parameter.

None of this applies to pinned regions.

Link: https://lore.kernel.org/r/20210712095039.8093-9-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:15 -04:00
Avri Altman 67001ff171 scsi: ufs: ufshpb: Add HPB dev reset response
The spec does not define what the host's recommended response is when the
device sends HPB dev reset response (oper 0x2).

Update all active HPB regions.

Link: https://lore.kernel.org/r/20210712095039.8093-8-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:15 -04:00
Avri Altman 6f4ad14f0f scsi: ufs: ufshpb: Region inactivation in host mode
In host mode, the host is expected to send HPB WRITE BUFFER with buffer-id
= 0x1 when it inactivates a region.

Use the map-requests pool as there is no point in assigning a designated
cache for umap-requests.

[mkp: REQ_OP_DRV_*]

Link: https://lore.kernel.org/r/20210712095039.8093-7-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:14 -04:00
Avri Altman 6c59cb501b scsi: ufs: ufshpb: Make eviction depend on region's reads
In host mode, eviction is considered an extreme measure. Verify that the
entering region has enough reads, and the exiting region has fewer reads.

Link: https://lore.kernel.org/r/20210712095039.8093-6-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:14 -04:00
Avri Altman c76a188856 scsi: ufs: ufshpb: Add reads counter
In host control mode, reads are the major source of activation trials.
Keep track of those reads counters, for both active as well inactive
regions.

We reset the read counter upon write - we are only interested in "clean"
reads.

Keep those counters normalized, as we are using those reads as a
comparative score, to make various decisions.  If during consecutive
normalizations an active region has exhaust its reads - inactivate it.

While at it, protect the {active,inactive}_count stats by adding them into
the applicable handler.

Link: https://lore.kernel.org/r/20210712095039.8093-5-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:14 -04:00
Avri Altman 8becf4db1e scsi: ufs: ufshpb: Transform set_dirty to iterate_rgn
Given a transfer length, set_dirty meticulously iterates over all the
entries, across subregions and regions if needed. Currently its only use is
to mark dirty blocks, but HCM may benefit from it as well to manage its
read counters.

Link: https://lore.kernel.org/r/20210712095039.8093-4-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:14 -04:00
Avri Altman 3a2c1f6803 scsi: ufs: ufshpb: Add host control mode support to rsp_upiu
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.

Conversely, 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.

Link: https://lore.kernel.org/r/20210712095039.8093-3-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:14 -04:00
Avri Altman 119ee38c10 scsi: ufs: ufshpb: Cache HPB Control mode on init
We will use control_mode later when we need to differentiate between device
and host control modes.

Link: https://lore.kernel.org/r/20210712095039.8093-2-avri.altman@wdc.com
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:14 -04:00
Daejun Park 41d8a9333c scsi: ufs: ufshpb: Add HPB 2.0 support
Version 2.0 of HBP supports reads of varying sizes from 4KB to 1MB.

A read operation <= 32KB is supported as single HPB read. A read between
36KB and 1MB is supported by 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.

[mkp: REQ_OP_DRV_* and blk_rq_is_passthrough()]

Link: https://lore.kernel.org/r/20210712090025epcms2p3b3d94f6f1b2cfa394e3d9ba130ca0fa7@epcms2p3
Tested-by: Can Guo <cang@codeaurora.org>
Tested-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:05:07 -04:00
Daejun Park 2fff76f875 scsi: ufs: ufshpb: Prepare HPB read for cached sub-region
If the logical address of a read I/O belongs to an active sub-region, the
HPB driver modifies the read I/O command to an HPB read. The driver
modifies the UFS UPIU instead of modifying the existing SCSI command.

In HPB version 1.0, the maximum read I/O size that can be converted to HPB
read is 4KB.

The dirty map of the active sub-region prevents an incorrect HPB read that
has stale physical page number which is updated by previous write I/O.

[mkp: REQ_OP_DRV_* and blk_rq_is_passthrough()]

Link: https://lore.kernel.org/r/20210712085936epcms2p4b0ec5c8cecdeea6cc043d684363842b6@epcms2p4
Tested-by: Bean Huo <beanhuo@micron.com>
Tested-by: Can Guo <cang@codeaurora.org>
Tested-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:04:55 -04:00
Daejun Park 4b5f49079c scsi: ufs: ufshpb: L2P map management for HPB read
Implement L2P map management in HPB.

The HPB divides logical addresses into several regions. A region consists
of several sub-regions. The sub-region is a basic unit where L2P mapping is
managed. The driver loads L2P mapping data of each sub-region. The loaded
sub-region is called active-state. The HPB driver unloads L2P mapping data
as region unit. The unloaded region is called inactive-state.

Sub-region/region candidates to be loaded and unloaded are delivered from
the UFS device. The UFS device delivers the recommended active sub-region
and inactivate region to the driver using sense data. The HPB module
performs L2P mapping management on the host through the delivered
information.

A pinned region is a preset region on the UFS device that is always
in activate-state.

The data structures for map data requests and L2P mappings use the mempool
API, minimizing allocation overhead while avoiding static allocation.

The mininum size of the memory pool used in the HPB is implemented
as a module parameter so that it can be configurable by the user.

To guarantee a minimum memory pool size of 4MB: ufshpb_host_map_kbytes=4096.

The map_work manages active/inactive via 2 "to-do" lists:

 - hpb->lh_inact_rgn: regions to be inactivated
 - hpb->lh_act_srgn: subregions to be activated

These lists are maintained on I/O completion.

[mkp: switch to REQ_OP_DRV_*]

Link: https://lore.kernel.org/r/20210712085859epcms2p36e420f19564f6cd0c4a45d54949619eb@epcms2p3
Tested-by: Bean Huo <beanhuo@micron.com>
Tested-by: Can Guo <cang@codeaurora.org>
Tested-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:04:41 -04:00
Daejun Park f02bc9754a scsi: ufs: ufshpb: Introduce Host Performance Buffer feature
Implement Host Performance Buffer (HPB) initialization and add function
calls to UFS core driver.

NAND flash-based storage devices, including UFS, have mechanisms to
translate logical addresses of I/O requests to the corresponding physical
addresses of the flash storage.  In UFS, logical-to-physical-address (L2P)
map data, which is required to identify the physical address for the
requested I/Os, can only be partially stored in SRAM from NAND flash. Due
to this partial loading, accessing the flash address area, where the L2P
information for that address is not loaded in the SRAM, can result in
serious performance degradation.

The basic concept of HPB is to cache L2P mapping entries in host system
memory so that both physical block address (PBA) and logical block address
(LBA) can be delivered in HPB read command. The HPB read command allows to
read data faster than a regular read command in UFS since it provides the
physical address (HPB Entry) of the desired logical block in addition to
its logical address. The UFS device can access the physical block in NAND
directly without searching and uploading L2P mapping table. This improves
read performance because the NAND read operation for uploading L2P mapping
table is removed.

In HPB initialization, the host checks if the UFS device supports HPB
feature and retrieves related device capabilities. Then, HPB parameters are
configured in the device.

Total start-up time of popular applications was measured and the difference
observed between HPB being enabled and disabled. Popular applications are
12 game apps and 24 non-game apps. Each test cycle consists of running 36
applications in sequence. We repeated the cycle for observing performance
improvement by L2P mapping cache hit in HPB.

The following is the test environment:

 - kernel version: 4.4.0
 - RAM: 8GB
 - UFS 2.1 (64GB)

Results:

   +-------+----------+----------+-------+
   | cycle | baseline | with HPB | diff  |
   +-------+----------+----------+-------+
   | 1     | 272.4    | 264.9    | -7.5  |
   | 2     | 250.4    | 248.2    | -2.2  |
   | 3     | 226.2    | 215.6    | -10.6 |
   | 4     | 230.6    | 214.8    | -15.8 |
   | 5     | 232.0    | 218.1    | -13.9 |
   | 6     | 231.9    | 212.6    | -19.3 |
   +-------+----------+----------+-------+

We also measured HPB performance using iozone:

   $ iozone -r 4k -+n -i2 -ecI -t 16 -l 16 -u 16 -s $IO_RANGE/16 -F \
   mnt/tmp_1 mnt/tmp_2 mnt/tmp_3 mnt/tmp_4 mnt/tmp_5 mnt/tmp_6 mnt/tmp_7 \
   mnt/tmp_8 mnt/tmp_9 mnt/tmp_10 mnt/tmp_11 mnt/tmp_12 mnt/tmp_13 \
   mnt/tmp_14 mnt/tmp_15 mnt/tmp_16

Results:

   +----------+--------+---------+
   | IO range | HPB on | HPB off |
   +----------+--------+---------+
   |   1 GB   | 294.8  | 300.87  |
   |   4 GB   | 293.51 | 179.35  |
   |   8 GB   | 294.85 | 162.52  |
   |  16 GB   | 293.45 | 156.26  |
   |  32 GB   | 277.4  | 153.25  |
   +----------+--------+---------+

Link: https://lore.kernel.org/r/20210712085830epcms2p8c1288b7f7a81b044158a18232617b572@epcms2p8
Reported-by: kernel test robot <lkp@intel.com>
Tested-by: Bean Huo <beanhuo@micron.com>
Tested-by: Can Guo <cang@codeaurora.org>
Tested-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-01 16:04:23 -04:00