scsi: ufs: core: Introduce HBA performance monitor sysfs nodes

Add a new sysfs group which has nodes to monitor data/request transfer
performance. This sysfs group has nodes showing total sectors/requests
transferred, total busy time spent and max/min/avg/sum latencies. This
group can be enhanced later to show more UFS driver layer performance
statistics data during runtime.

Link: https://lore.kernel.org/r/1619058521-35307-2-git-send-email-cang@codeaurora.org
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Acked-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 126 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-ufs b/Documentation/ABI/testing/sysfs-driver-ufs
index d1bc23cb6a9d..8380866d8ed0 100644
--- a/Documentation/ABI/testing/sysfs-driver-ufs
+++ b/Documentation/ABI/testing/sysfs-driver-ufs
@@ -995,6 +995,132 @@ Description:	This entry shows the target state of an UFS UIC link
 
 		The file is read only.
 
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/monitor_enable
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the status of performance monitor enablement
+		and it can be used to start/stop the monitor. When the monitor
+		is stopped, the performance data collected is also cleared.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/monitor_chunk_size
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file tells the monitor to focus on requests transferring
+		data of specific chunk size (in Bytes). 0 means any chunk size.
+		It can only be changed when monitor is disabled.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_total_sectors
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows how many sectors (in 512 Bytes) have been
+		sent from device to host after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_total_busy
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows how long (in micro seconds) has been spent
+		sending data from device to host after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_nr_requests
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows how many read requests have been sent after
+		monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_max
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the maximum latency (in micro seconds) of
+		read requests after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_min
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the minimum latency (in micro seconds) of
+		read requests after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_avg
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the average latency (in micro seconds) of
+		read requests after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/read_req_latency_sum
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the total latency (in micro seconds) of
+		read requests sent after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_total_sectors
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows how many sectors (in 512 Bytes) have been sent
+		from host to device after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_total_busy
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows how long (in micro seconds) has been spent
+		sending data from host to device after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_nr_requests
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows how many write requests have been sent after
+		monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_max
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the maximum latency (in micro seconds) of write
+		requests after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_min
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the minimum latency (in micro seconds) of write
+		requests after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_avg
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the average latency (in micro seconds) of write
+		requests after monitor gets started.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/monitor/write_req_latency_sum
+Date:		January 2021
+Contact:	Can Guo <cang@codeaurora.org>
+Description:	This file shows the total latency (in micro seconds) of write
+		requests after monitor gets started.
+
+		The file is read only.
+
 What:		/sys/bus/platform/drivers/ufshcd/*/device_descriptor/wb_presv_us_en
 Date:		June 2020
 Contact:	Asutosh Das <asutoshd@codeaurora.org>