user/sven/linux.git/include/linux/resctrl.h, branch v5.15.87

x86/resctrl: Make resctrl_arch_get_config() return its value

2021-08-11T16:42:53Z

resctrl_arch_get_config() has no return, but does pass a single value back via one of its arguments. Return the value instead. Suggested-by: Borislav Petkov Signed-off-by: James Morse Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210811163831.14917-1-james.morse@arm.com

x86/resctrl: Calculate the index from the configuration type

2021-08-11T16:19:06Z

resctrl uses cbm_idx() to map a closid to an index in the configuration array. This is based on a multiplier and offset that are held in the resource. To merge the resources, the resctrl arch code needs to calculate the index from something else, as there will only be one resource. Decide based on the staged configuration type. This makes the static mult and offset parameters redundant. [ bp: Remove superfluous brackets in get_config_index() ] Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-21-james.morse@arm.com

x86/resctrl: Pass configuration type to resctrl_arch_get_config()

2021-08-11T15:53:53Z

The ctrl_val[] array for a struct rdt_hw_resource only holds configurations of one type. The type is implicit. Once the CDP resources are merged, the ctrl_val[] array will hold all the configurations for the hardware resource. When a particular type of configuration is needed, it must be specified explicitly. Pass the expected type from the schema into resctrl_arch_get_config(). Nothing uses this yet, but once a single ctrl_val[] array is used for the three struct rdt_hw_resources that share hardware, the type will be used to return the correct configuration value from the shared array. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-18-james.morse@arm.com

x86/resctrl: Add a helper to read a closid's configuration

2021-08-11T15:46:34Z

Functions like show_doms() reach into the architecture's private structure to retrieve the configuration from the struct rdt_hw_resource. The hardware configuration may look completely different to the values resctrl gets from user-space. The staged configuration and resctrl_arch_update_domains() allow the architecture to convert or translate these values. Resctrl shouldn't read or write the ctrl_val[] values directly. Add a helper to read the current configuration. This will allow another architecture to scale the bitmaps if necessary, and possibly use controls that don't take the user-space control format at all. Of the remaining functions that access ctrl_val[] directly, apply_config() is part of the architecture-specific code, and is called via resctrl_arch_update_domains(). reset_all_ctrls() will be an architecture specific helper. update_mba_bw() manipulates both ctrl_val[], mbps_val[] and the hardware. The mbps_val[] that matches the mba_sc state of the resource is changed, but the other is left unchanged. Abstracting this is the subject of later patches that affect set_mba_sc() too. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-17-james.morse@arm.com

x86/resctrl: Rename update_domains() to resctrl_arch_update_domains()

2021-08-11T14:36:58Z

update_domains() merges the staged configuration changes into the arch codes configuration array. Rename to make it clear it is part of the arch code interface to resctrl. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-16-james.morse@arm.com

x86/resctrl: Allow different CODE/DATA configurations to be staged

2021-08-11T14:33:42Z

Before the CDP resources can be merged, struct rdt_domain will need an array of struct resctrl_staged_config, one per type of configuration. Use the type as an index to the array to ensure that a schema configuration string can't specify the same domain twice. This will allow two schemata to apply configuration changes to one resource. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-15-james.morse@arm.com

x86/resctrl: Group staged configuration into a separate struct

2021-08-11T14:32:32Z

When configuration changes are made, the new value is written to struct rdt_domain's new_ctrl field and the have_new_ctrl flag is set. Later new_ctrl is copied to hardware by a call to update_domains(). Once the CDP resources are merged, there will be one new_ctrl field in use by two struct resctrl_schema requiring a per-schema IPI to copy the value to hardware. Move new_ctrl and have_new_ctrl into a new struct resctrl_staged_config. Before the CDP resources can be merged, struct rdt_domain will need an array of these, one per type of configuration. Using the type as an index to the array will ensure that a schema configuration string can't specify the same domain twice. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-14-james.morse@arm.com

x86/resctrl: Move the schemata names into struct resctrl_schema

2021-08-11T14:21:35Z

resctrl 'info' directories and schema parsing use the schema name. This lives in the struct rdt_resource, and is specified by the architecture code. Once the CDP resources are merged, there will only be one resource (and one name) in use by two schemata. To allow the CDP CODE/DATA property to be the type of configuration the schema uses, the name should also be per-schema. Add a name field to struct resctrl_schema, and use this wherever the schema name is exposed (or read from) user-space. Calculating max_name_width for padding the schemata file also moves as this is visible to user-space. As the names in struct rdt_resource already include the CDP information, schemata_list_create() copies them. schemata_list_create() includes the length of the CDP suffix when calculating max_name_width in preparation for CDP resources being merged. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-13-james.morse@arm.com

x86/resctrl: Add a helper to read/set the CDP configuration

2021-08-11T13:54:26Z

Whether CDP is enabled for a hardware resource like the L3 cache can be found by inspecting the alloc_enabled flags of the L3CODE/L3DATA struct rdt_hw_resources, even if they aren't in use. Once these resources are merged, the flags can't be compared. Whether CDP is enabled needs tracking explicitly. If another architecture is emulating CDP the behaviour may not be per-resource. 'cdp_capable' needs to be visible to resctrl, even if its not in use, as this affects the padding of the schemata table visible to user-space. Add cdp_enabled to struct rdt_hw_resource and cdp_capable to struct rdt_resource. Add resctrl_arch_set_cdp_enabled() to let resctrl enable or disable CDP on a resource. resctrl_arch_get_cdp_enabled() lets it read the current state. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-12-james.morse@arm.com

x86/resctrl: Pass the schema to resctrl filesystem functions

2021-08-11T13:43:54Z

Once the CDP resources are merged, there will be two struct resctrl_schema for one struct rdt_resource. CDP becomes a type of configuration that belongs to the schema. Helpers like rdtgroup_cbm_overlaps() need access to the schema to query the configuration (or configurations) based on schema properties. Change these functions to take a struct schema instead of the struct rdt_resource. All the modified functions are part of the filesystem code that will move to /fs/resctrl once it is possible to support a second architecture. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Reinette Chatre Tested-by: Babu Moger Link: https://lkml.kernel.org/r/20210728170637.25610-10-james.morse@arm.com