Loading Documentation/ABI/stable/sysfs-driver-dma-idxd +9 −0 Original line number Diff line number Diff line Loading @@ -128,6 +128,8 @@ Date: Aug 28, 2020 KernelVersion: 5.10.0 Contact: dmaengine@vger.kernel.org Description: The last executed device administrative command's status/error. Also last configuration error overloaded. Writing to it will clear the status. What: /sys/bus/dsa/devices/wq<m>.<n>/block_on_fault Date: Oct 27, 2020 Loading Loading @@ -211,6 +213,13 @@ Contact: dmaengine@vger.kernel.org Description: Indicate whether ATS disable is turned on for the workqueue. 0 indicates ATS is on, and 1 indicates ATS is off for the workqueue. What: /sys/bus/dsa/devices/wq<m>.<n>/occupancy Date May 25, 2021 KernelVersion: 5.14.0 Contact: dmaengine@vger.kernel.org Description: Show the current number of entries in this WQ if WQ Occupancy Support bit WQ capabilities is 1. What: /sys/bus/dsa/devices/engine<m>.<n>/group_id Date: Oct 25, 2019 KernelVersion: 5.6.0 Loading Documentation/ABI/testing/debugfs-driver-habanalabs +19 −0 Original line number Diff line number Diff line Loading @@ -215,6 +215,17 @@ Description: Sets the skip reset on timeout option for the device. Value of "0" means device will be reset in case some CS has timed out, otherwise it will not be reset. What: /sys/kernel/debug/habanalabs/hl<n>/state_dump Date: Oct 2021 KernelVersion: 5.15 Contact: ynudelman@habana.ai Description: Gets the state dump occurring on a CS timeout or failure. State dump is used for debug and is created each time in case of a problem in a CS execution, before reset. Reading from the node returns the newest state dump available. Writing an integer X discards X state dumps, so that the next read would return X+1-st newest state dump. What: /sys/kernel/debug/habanalabs/hl<n>/stop_on_err Date: Mar 2020 KernelVersion: 5.6 Loading @@ -230,6 +241,14 @@ Description: Displays a list with information about the currently user pointers (user virtual addresses) that are pinned and mapped to DMA addresses What: /sys/kernel/debug/habanalabs/hl<n>/userptr_lookup Date: Aug 2021 KernelVersion: 5.15 Contact: ogabbay@kernel.org Description: Allows to search for specific user pointers (user virtual addresses) that are pinned and mapped to DMA addresses, and see their resolution to the specific dma address. What: /sys/kernel/debug/habanalabs/hl<n>/vm Date: Jan 2019 KernelVersion: 5.1 Loading Documentation/ABI/testing/sysfs-bus-pci +17 −0 Original line number Diff line number Diff line Loading @@ -121,6 +121,23 @@ Description: child buses, and re-discover devices removed earlier from this part of the device tree. What: /sys/bus/pci/devices/.../reset_method Date: August 2021 Contact: Amey Narkhede <ameynarkhede03@gmail.com> Description: Some devices allow an individual function to be reset without affecting other functions in the same slot. For devices that have this support, a file named reset_method is present in sysfs. Reading this file gives names of the supported and enabled reset methods and their ordering. Writing a space-separated list of names of reset methods sets the reset methods and ordering to be used when resetting the device. Writing an empty string disables the ability to reset the device. Writing "default" enables all supported reset methods in the default ordering. What: /sys/bus/pci/devices/.../reset Date: July 2009 Contact: Michael S. Tsirkin <mst@redhat.com> Loading Documentation/ABI/testing/sysfs-driver-ufs +236 −0 Original line number Diff line number Diff line Loading @@ -1298,3 +1298,239 @@ Description: This node is used to set or display whether UFS WriteBooster is (if the platform supports UFSHCD_CAP_CLK_SCALING). For a platform that doesn't support UFSHCD_CAP_CLK_SCALING, we can disable/enable WriteBooster through this sysfs node. What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_version Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the HPB specification version. The full information about the descriptor can be found in the UFS HPB (Host Performance Booster) Extension specifications. Example: version 1.2.3 = 0123h The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_control Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows an indication of the HPB control mode. 00h: Host control mode 01h: Device control mode The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_region_size Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the bHPBRegionSize which can be calculated as in the following (in bytes): HPB Region size = 512B * 2^bHPBRegionSize The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_number_lu Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum number of HPB LU supported by the device. 00h: HPB is not supported by the device. 01h ~ 20h: Maximum number of HPB LU supported by the device The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_subregion_size Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the bHPBSubRegionSize, which can be calculated as in the following (in bytes) and shall be a multiple of logical block size: HPB Sub-Region size = 512B x 2^bHPBSubRegionSize bHPBSubRegionSize shall not exceed bHPBRegionSize. The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_max_active_regions Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum number of active HPB regions that is supported by the device. The file is read only. What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_lu_max_active_regions Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum number of HPB regions assigned to the HPB logical unit. The file is read only. What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_pinned_region_start_offset Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the start offset of HPB pinned region. The file is read only. What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_number_pinned_regions Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of HPB pinned regions assigned to the HPB logical unit. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/hit_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of reads that changed to HPB read. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/miss_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of reads that cannot be changed to HPB read. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/rb_noti_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of response UPIUs that has recommendations for activating sub-regions and/or inactivating region. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/rb_active_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of active sub-regions recommended by response UPIUs. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/rb_inactive_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of inactive regions recommended by response UPIUs. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/map_req_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of read buffer commands for activating sub-regions recommended by response UPIUs. The file is read only. What: /sys/class/scsi_device/*/device/hpb_params/requeue_timeout_ms Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the requeue timeout threshold for write buffer command in ms. The value can be changed by writing an integer to this entry. What: /sys/bus/platform/drivers/ufshcd/*/attributes/max_data_size_hpb_single_cmd Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum HPB data size for using a single HPB command. === ======== 00h 4KB 01h 8KB 02h 12KB ... FFh 1024KB === ======== The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/flags/hpb_enable Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the status of HPB. == ============================ 0 HPB is not enabled. 1 HPB is enabled == ============================ The file is read only. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/activation_thld Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In host control mode, reads are the major source of activation trials. Once this threshold hs met, the region is added to the "to-be-activated" list. Since we reset the read counter upon write, this include sending a rb command updating the region ppn as well. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/normalization_factor Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In host control mode, we think of the regions as "buckets". Those buckets are being filled with reads, and emptied on write. We use entries_per_srgn - the amount of blocks in a subregion as our bucket size. This applies because HPB1.0 only handles single-block reads. Once the bucket size is crossed, we trigger a normalization work - not only to avoid overflow, but mainly because we want to keep those counters normalized, as we are using those reads as a comparative score, to make various decisions. The normalization is dividing (shift right) the read counter by the normalization_factor. If during consecutive normalizations an active region has exhausted its reads - inactivate it. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/eviction_thld_enter Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: Region deactivation is often due to the fact that eviction took place: A region becomes active at the expense of another. This is happening when the max-active-regions limit has been crossed. In host mode, eviction is considered an extreme measure. We want to verify that the entering region has enough reads, and the exiting region has much fewer reads. eviction_thld_enter is the min reads that a region must have in order to be considered a candidate for evicting another region. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/eviction_thld_exit Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: Same as above for the exiting region. A region is considered to be a candidate for eviction only if it has fewer reads than eviction_thld_exit. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/read_timeout_ms Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In order not to hang on to "cold" regions, we inactivate a region that has no READ access for a predefined amount of time - read_timeout_ms. If read_timeout_ms has expired, and the region is dirty, it is less likely that we can make any use of HPB reading it so we inactivate it. Still, deactivation has its overhead, and we may still benefit from HPB reading this region if it is clean - see read_timeout_expiries. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/read_timeout_expiries Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: If the region read timeout has expired, but the region is clean, just re-wind its timer for another spin. Do that as long as it is clean and did not exhaust its read_timeout_expiries threshold. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/timeout_polling_interval_ms Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: The frequency with which the delayed worker that checks the read_timeouts is awakened. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/inflight_map_req Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In host control mode the host is the originator of map requests. To avoid flooding the device with map requests, use a simple throttling mechanism that limits the number of inflight map requests. Documentation/ABI/testing/sysfs-fs-f2fs +21 −2 Original line number Diff line number Diff line Loading @@ -41,8 +41,7 @@ Description: This parameter controls the number of prefree segments to be What: /sys/fs/f2fs/<disk>/main_blkaddr Date: November 2019 Contact: "Ramon Pantin" <pantin@google.com> Description: Shows first block address of MAIN area. Description: Shows first block address of MAIN area. What: /sys/fs/f2fs/<disk>/ipu_policy Date: November 2013 Loading Loading @@ -493,3 +492,23 @@ Contact: "Chao Yu" <yuchao0@huawei.com> Description: When ATGC is on, it controls age threshold to bypass GCing young candidates whose age is not beyond the threshold, by default it was initialized as 604800 seconds (equals to 7 days). What: /sys/fs/f2fs/<disk>/gc_reclaimed_segments Date: July 2021 Contact: "Daeho Jeong" <daehojeong@google.com> Description: Show how many segments have been reclaimed by GC during a specific GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy, 3: GC idle AT, 4: GC urgent high, 5: GC urgent low) You can re-initialize this value to "0". What: /sys/fs/f2fs/<disk>/gc_segment_mode Date: July 2021 Contact: "Daeho Jeong" <daehojeong@google.com> Description: You can control for which gc mode the "gc_reclaimed_segments" node shows. Refer to the description of the modes in "gc_reclaimed_segments". What: /sys/fs/f2fs/<disk>/seq_file_ra_mul Date: July 2021 Contact: "Daeho Jeong" <daehojeong@google.com> Description: You can control the multiplier value of bdi device readahead window size between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option. Loading
Documentation/ABI/stable/sysfs-driver-dma-idxd +9 −0 Original line number Diff line number Diff line Loading @@ -128,6 +128,8 @@ Date: Aug 28, 2020 KernelVersion: 5.10.0 Contact: dmaengine@vger.kernel.org Description: The last executed device administrative command's status/error. Also last configuration error overloaded. Writing to it will clear the status. What: /sys/bus/dsa/devices/wq<m>.<n>/block_on_fault Date: Oct 27, 2020 Loading Loading @@ -211,6 +213,13 @@ Contact: dmaengine@vger.kernel.org Description: Indicate whether ATS disable is turned on for the workqueue. 0 indicates ATS is on, and 1 indicates ATS is off for the workqueue. What: /sys/bus/dsa/devices/wq<m>.<n>/occupancy Date May 25, 2021 KernelVersion: 5.14.0 Contact: dmaengine@vger.kernel.org Description: Show the current number of entries in this WQ if WQ Occupancy Support bit WQ capabilities is 1. What: /sys/bus/dsa/devices/engine<m>.<n>/group_id Date: Oct 25, 2019 KernelVersion: 5.6.0 Loading
Documentation/ABI/testing/debugfs-driver-habanalabs +19 −0 Original line number Diff line number Diff line Loading @@ -215,6 +215,17 @@ Description: Sets the skip reset on timeout option for the device. Value of "0" means device will be reset in case some CS has timed out, otherwise it will not be reset. What: /sys/kernel/debug/habanalabs/hl<n>/state_dump Date: Oct 2021 KernelVersion: 5.15 Contact: ynudelman@habana.ai Description: Gets the state dump occurring on a CS timeout or failure. State dump is used for debug and is created each time in case of a problem in a CS execution, before reset. Reading from the node returns the newest state dump available. Writing an integer X discards X state dumps, so that the next read would return X+1-st newest state dump. What: /sys/kernel/debug/habanalabs/hl<n>/stop_on_err Date: Mar 2020 KernelVersion: 5.6 Loading @@ -230,6 +241,14 @@ Description: Displays a list with information about the currently user pointers (user virtual addresses) that are pinned and mapped to DMA addresses What: /sys/kernel/debug/habanalabs/hl<n>/userptr_lookup Date: Aug 2021 KernelVersion: 5.15 Contact: ogabbay@kernel.org Description: Allows to search for specific user pointers (user virtual addresses) that are pinned and mapped to DMA addresses, and see their resolution to the specific dma address. What: /sys/kernel/debug/habanalabs/hl<n>/vm Date: Jan 2019 KernelVersion: 5.1 Loading
Documentation/ABI/testing/sysfs-bus-pci +17 −0 Original line number Diff line number Diff line Loading @@ -121,6 +121,23 @@ Description: child buses, and re-discover devices removed earlier from this part of the device tree. What: /sys/bus/pci/devices/.../reset_method Date: August 2021 Contact: Amey Narkhede <ameynarkhede03@gmail.com> Description: Some devices allow an individual function to be reset without affecting other functions in the same slot. For devices that have this support, a file named reset_method is present in sysfs. Reading this file gives names of the supported and enabled reset methods and their ordering. Writing a space-separated list of names of reset methods sets the reset methods and ordering to be used when resetting the device. Writing an empty string disables the ability to reset the device. Writing "default" enables all supported reset methods in the default ordering. What: /sys/bus/pci/devices/.../reset Date: July 2009 Contact: Michael S. Tsirkin <mst@redhat.com> Loading
Documentation/ABI/testing/sysfs-driver-ufs +236 −0 Original line number Diff line number Diff line Loading @@ -1298,3 +1298,239 @@ Description: This node is used to set or display whether UFS WriteBooster is (if the platform supports UFSHCD_CAP_CLK_SCALING). For a platform that doesn't support UFSHCD_CAP_CLK_SCALING, we can disable/enable WriteBooster through this sysfs node. What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_version Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the HPB specification version. The full information about the descriptor can be found in the UFS HPB (Host Performance Booster) Extension specifications. Example: version 1.2.3 = 0123h The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_control Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows an indication of the HPB control mode. 00h: Host control mode 01h: Device control mode The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_region_size Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the bHPBRegionSize which can be calculated as in the following (in bytes): HPB Region size = 512B * 2^bHPBRegionSize The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_number_lu Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum number of HPB LU supported by the device. 00h: HPB is not supported by the device. 01h ~ 20h: Maximum number of HPB LU supported by the device The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_subregion_size Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the bHPBSubRegionSize, which can be calculated as in the following (in bytes) and shall be a multiple of logical block size: HPB Sub-Region size = 512B x 2^bHPBSubRegionSize bHPBSubRegionSize shall not exceed bHPBRegionSize. The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/geometry_descriptor/hpb_max_active_regions Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum number of active HPB regions that is supported by the device. The file is read only. What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_lu_max_active_regions Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum number of HPB regions assigned to the HPB logical unit. The file is read only. What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_pinned_region_start_offset Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the start offset of HPB pinned region. The file is read only. What: /sys/class/scsi_device/*/device/unit_descriptor/hpb_number_pinned_regions Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of HPB pinned regions assigned to the HPB logical unit. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/hit_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of reads that changed to HPB read. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/miss_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of reads that cannot be changed to HPB read. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/rb_noti_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of response UPIUs that has recommendations for activating sub-regions and/or inactivating region. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/rb_active_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of active sub-regions recommended by response UPIUs. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/rb_inactive_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of inactive regions recommended by response UPIUs. The file is read only. What: /sys/class/scsi_device/*/device/hpb_stats/map_req_cnt Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the number of read buffer commands for activating sub-regions recommended by response UPIUs. The file is read only. What: /sys/class/scsi_device/*/device/hpb_params/requeue_timeout_ms Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the requeue timeout threshold for write buffer command in ms. The value can be changed by writing an integer to this entry. What: /sys/bus/platform/drivers/ufshcd/*/attributes/max_data_size_hpb_single_cmd Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the maximum HPB data size for using a single HPB command. === ======== 00h 4KB 01h 8KB 02h 12KB ... FFh 1024KB === ======== The file is read only. What: /sys/bus/platform/drivers/ufshcd/*/flags/hpb_enable Date: June 2021 Contact: Daejun Park <daejun7.park@samsung.com> Description: This entry shows the status of HPB. == ============================ 0 HPB is not enabled. 1 HPB is enabled == ============================ The file is read only. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/activation_thld Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In host control mode, reads are the major source of activation trials. Once this threshold hs met, the region is added to the "to-be-activated" list. Since we reset the read counter upon write, this include sending a rb command updating the region ppn as well. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/normalization_factor Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In host control mode, we think of the regions as "buckets". Those buckets are being filled with reads, and emptied on write. We use entries_per_srgn - the amount of blocks in a subregion as our bucket size. This applies because HPB1.0 only handles single-block reads. Once the bucket size is crossed, we trigger a normalization work - not only to avoid overflow, but mainly because we want to keep those counters normalized, as we are using those reads as a comparative score, to make various decisions. The normalization is dividing (shift right) the read counter by the normalization_factor. If during consecutive normalizations an active region has exhausted its reads - inactivate it. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/eviction_thld_enter Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: Region deactivation is often due to the fact that eviction took place: A region becomes active at the expense of another. This is happening when the max-active-regions limit has been crossed. In host mode, eviction is considered an extreme measure. We want to verify that the entering region has enough reads, and the exiting region has much fewer reads. eviction_thld_enter is the min reads that a region must have in order to be considered a candidate for evicting another region. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/eviction_thld_exit Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: Same as above for the exiting region. A region is considered to be a candidate for eviction only if it has fewer reads than eviction_thld_exit. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/read_timeout_ms Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In order not to hang on to "cold" regions, we inactivate a region that has no READ access for a predefined amount of time - read_timeout_ms. If read_timeout_ms has expired, and the region is dirty, it is less likely that we can make any use of HPB reading it so we inactivate it. Still, deactivation has its overhead, and we may still benefit from HPB reading this region if it is clean - see read_timeout_expiries. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/read_timeout_expiries Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: If the region read timeout has expired, but the region is clean, just re-wind its timer for another spin. Do that as long as it is clean and did not exhaust its read_timeout_expiries threshold. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/timeout_polling_interval_ms Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: The frequency with which the delayed worker that checks the read_timeouts is awakened. What: /sys/class/scsi_device/*/device/hpb_param_sysfs/inflight_map_req Date: February 2021 Contact: Avri Altman <avri.altman@wdc.com> Description: In host control mode the host is the originator of map requests. To avoid flooding the device with map requests, use a simple throttling mechanism that limits the number of inflight map requests.
Documentation/ABI/testing/sysfs-fs-f2fs +21 −2 Original line number Diff line number Diff line Loading @@ -41,8 +41,7 @@ Description: This parameter controls the number of prefree segments to be What: /sys/fs/f2fs/<disk>/main_blkaddr Date: November 2019 Contact: "Ramon Pantin" <pantin@google.com> Description: Shows first block address of MAIN area. Description: Shows first block address of MAIN area. What: /sys/fs/f2fs/<disk>/ipu_policy Date: November 2013 Loading Loading @@ -493,3 +492,23 @@ Contact: "Chao Yu" <yuchao0@huawei.com> Description: When ATGC is on, it controls age threshold to bypass GCing young candidates whose age is not beyond the threshold, by default it was initialized as 604800 seconds (equals to 7 days). What: /sys/fs/f2fs/<disk>/gc_reclaimed_segments Date: July 2021 Contact: "Daeho Jeong" <daehojeong@google.com> Description: Show how many segments have been reclaimed by GC during a specific GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy, 3: GC idle AT, 4: GC urgent high, 5: GC urgent low) You can re-initialize this value to "0". What: /sys/fs/f2fs/<disk>/gc_segment_mode Date: July 2021 Contact: "Daeho Jeong" <daehojeong@google.com> Description: You can control for which gc mode the "gc_reclaimed_segments" node shows. Refer to the description of the modes in "gc_reclaimed_segments". What: /sys/fs/f2fs/<disk>/seq_file_ra_mul Date: July 2021 Contact: "Daeho Jeong" <daehojeong@google.com> Description: You can control the multiplier value of bdi device readahead window size between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option.
