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2021-08-11x86/resctrl: Make resctrl_arch_get_config() return its valueJames Morse1-8/+12
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 <bp@alien8.de> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210811163831.14917-1-james.morse@arm.com
2021-08-11x86/resctrl: Merge the CDP resourcesJames Morse1-67/+73
resctrl uses struct rdt_resource to describe the available hardware resources. The domains of the CDP aliases share a single ctrl_val[] array. The only differences between the struct rdt_hw_resource aliases is the name and conf_type. The name from struct rdt_hw_resource is visible to user-space. To support another architecture, as many user-visible details should be handled in the filesystem parts of the code that is common to all architectures. The name and conf_type go together. Remove conf_type and the CDP aliases. When CDP is supported and enabled, schemata_list_create() can create two schemata using the single resource, generating the CODE/DATA suffix to the schema name itself. This allows the alloc_ctrlval_array() and complications around free()ing the ctrl_val arrays to be removed. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-25-james.morse@arm.com
2021-08-11x86/resctrl: Remove rdt_cdp_peer_get()James Morse1-85/+14
When CDP is enabled, rdt_cdp_peer_get() finds the alternative CODE/DATA resource and returns the alternative domain. This is used to determine if bitmaps overlap when there are aliased entries in the two struct rdt_hw_resources. Now that the ctrl_val[] used by the CODE/DATA resources is the same, the search for an alternate resource/domain is not needed. Replace rdt_cdp_peer_get() with resctrl_peer_type(), which returns the alternative type. This can be passed to resctrl_arch_get_config() with the same resource and domain. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-23-james.morse@arm.com
2021-08-11x86/resctrl: Apply offset correction when config is stagedJames Morse1-7/+0
When resctrl comes to copy the CAT MSR values from the ctrl_val[] array into hardware, it applies an offset adjustment based on the type of the resource. CODE and DATA resources have their closid mapped into an odd/even range. This mapping is based on a property of the resource. This happens once the new control value has been written to the ctrl_val[] array. Once the CDP resources are merged, there will only be a single property that needs to cover both odd/even mappings to the single ctrl_val[] array. The offset adjustment must be applied before the new value is written to the array. Move the logic from cat_wrmsr() to resctrl_arch_update_domains(). The value provided to apply_config() is now an index in the array, not the closid. The parameters provided via struct msr_param are now indexes too. As resctrl's use of closid is a u32, struct msr_param's type is changed to match. With this, the CODE and DATA resources only use the odd or even indexes in the array. This allows the temporary num_closid/2 fixes in domain_setup_ctrlval() and reset_all_ctrls() to be removed. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-20-james.morse@arm.com
2021-08-11x86/resctrl: Make ctrlval arrays the same sizeJames Morse1-0/+9
The CODE and DATA resources report a num_closid that is half the actual size supported by the hardware. This behaviour is visible to user-space when CDP is enabled. The CODE and DATA resources have their own ctrlval arrays which are half the size of the underlying hardware because num_closid was already adjusted. One holds the odd configurations values, the other even. Before the CDP resources can be merged, the 'half the closids' behaviour needs to be implemented by schemata_list_create(), but this causes the ctrl_val[] array to be full sized. Remove the logic from the architecture specific rdt_get_cdp_config() setup, and add it to schemata_list_create(). Functions that walk all the configurations, such as domain_setup_ctrlval() and reset_all_ctrls(), take num_closid directly from struct rdt_hw_resource also have to halve num_closid as only the lower half of each array is in use. domain_setup_ctrlval() and reset_all_ctrls() both copy struct rdt_hw_resource's num_closid to a struct msr_param. Correct the value here. This is temporary as a subsequent patch will merge all three ctrl_val[] arrays such that when CDP is in use, the CODA/DATA layout in the array matches the hardware. reset_all_ctrls()'s loop over the whole of ctrl_val[] is not touched as this is harmless, and will be required as it is once the resources are merged. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-19-james.morse@arm.com
2021-08-11x86/resctrl: Pass configuration type to resctrl_arch_get_config()James Morse1-12/+23
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-18-james.morse@arm.com
2021-08-11x86/resctrl: Add a helper to read a closid's configurationJames Morse1-25/+18
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-17-james.morse@arm.com
2021-08-11x86/resctrl: Rename update_domains() to resctrl_arch_update_domains()James Morse1-1/+1
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-16-james.morse@arm.com
2021-08-11x86/resctrl: Allow different CODE/DATA configurations to be stagedJames Morse1-2/+3
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-15-james.morse@arm.com
2021-08-11x86/resctrl: Group staged configuration into a separate structJames Morse1-9/+13
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-14-james.morse@arm.com
2021-08-11x86/resctrl: Move the schemata names into struct resctrl_schemaJames Morse1-4/+25
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-13-james.morse@arm.com
2021-08-11x86/resctrl: Add a helper to read/set the CDP configurationJames Morse1-31/+44
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-12-james.morse@arm.com
2021-08-11x86/resctrl: Swizzle rdt_resource and resctrl_schema in pseudo_lock_regionJames Morse1-2/+2
struct pseudo_lock_region points to the rdt_resource. Once the resources are merged, this won't be unique. The resource name is moving into the schema, so that the filesystem portions of resctrl can generate it. Swap pseudo_lock_region's rdt_resource pointer for a schema pointer. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-11-james.morse@arm.com
2021-08-11x86/resctrl: Pass the schema to resctrl filesystem functionsJames Morse1-8/+11
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 <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-10-james.morse@arm.com
2021-08-11x86/resctrl: Add resctrl_arch_get_num_closid()James Morse1-2/+2
To initialise struct resctrl_schema's num_closid, schemata_list_create() reaches into the architectures private structure to retrieve num_closid from the struct rdt_hw_resource. The 'half the closids' behaviour should be part of the filesystem parts of resctrl that are the same on any architecture. struct resctrl_schema's num_closid should include any correction for CDP. Having two properties called num_closid is likely to be confusing when they have different values. Add a helper to read the resource's num_closid from the arch code. This should return the number of closid that the resource supports, regardless of whether CDP is in use. Once the CDP resources are merged, schemata_list_create() can apply the correction itself. Using a type with an obvious size for the arch helper means changing the type of num_closid to u32, which matches the type already used by struct rdtgroup. reset_all_ctrls() does not use resctrl_arch_get_num_closid(), even though it sets up a structure for modifying the hardware. This function will be part of the architecture code, the maximum closid should be the maximum value the hardware has, regardless of the way resctrl is using it. All the uses of num_closid in core.c are naturally part of the architecture specific code. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-9-james.morse@arm.com
2021-08-11x86/resctrl: Store the effective num_closid in the schemaJames Morse1-9/+4
Struct resctrl_schema holds properties that vary with the style of configuration that resctrl applies to a resource. There are already two values for the hardware's num_closid, depending on whether the architecture presents the L3 or L3CODE/L3DATA resources. As the way CDP changes the number of control groups that resctrl can create is part of the user-space interface, it should be managed by the filesystem parts of resctrl. This allows the architecture code to only describe the value the hardware supports. Add num_closid to resctrl_schema. This is the value seen by the filesystem, which may be different to the maximum value described by the arch code when CDP is enabled. These functions operate on the num_closid value that is exposed to user-space: * rdtgroup_parse_resource() * rdtgroup_schemata_show() * rdt_num_closids_show() * closid_init() Change them to use the schema value instead. schemata_list_create() sets this value, and reaches into the architecture-specific structure to get the value. This will eventually be replaced with a helper. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-8-james.morse@arm.com
2021-08-11x86/resctrl: Walk the resctrl schema list instead of an arch listJames Morse1-6/+12
When parsing a schema configuration value from user-space, resctrl walks the architectures rdt_resources_all[] array to find a matching struct rdt_resource. Once the CDP resources are merged there will be one resource in use by two schemata. Anything walking rdt_resources_all[] on behalf of a user-space request should walk the list of struct resctrl_schema instead. Change the users of for_each_alloc_enabled_rdt_resource() to walk the schema instead. Schemata were only created for alloc_enabled resources so these two lists are currently equivalent. schemata_list_create() and rdt_kill_sb() are ignored. The first creates the schema list, and will eventually loop over the resource indexes using an arch helper to retrieve the resource. rdt_kill_sb() will eventually make use of an arch 'reset everything' helper. After the filesystem code is moved, rdtgroup_pseudo_locked_in_hierarchy() remains part of the x86 specific hooks to support pseudo lock. This code walks each domain, and still does this after the separate resources are merged. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-7-james.morse@arm.com
2021-08-11x86/resctrl: Label the resources with their configuration typeJames Morse1-0/+1
The names of resources are used for the schema name presented to user-space. The name used is rooted in a structure provided by the architecture code because the names are different when CDP is enabled. x86 implements this by swapping between two sets of resource structures based on their alloc_enabled flag. The type of configuration in-use is encoded in the name (and cbm_idx_offset). Once the CDP behaviour is moved into the parts of resctrl that will move to /fs/, there will be two struct resctrl_schema for one struct rdt_resource. The schema describes the type of configuration being applied to the resource. The name of the schema should be generated by resctrl, base on the type of configuration. To do this struct resctrl_schema needs to store the type of configuration in use for a schema. Create an enum resctrl_conf_type describing the options, and add it to struct resctrl_schema. The underlying resources are still separate, as cbm_idx_offset is still in use. Temporarily label all the entries in rdt_resources_all[] and copy that value to struct resctrl_schema. Copying the value ensures there is no mismatch while the filesystem parts of resctrl are modified to use the schema. Once the resources are merged, the filesystem code can assign this value based on the schema being created. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-6-james.morse@arm.com
2021-08-11x86/resctrl: Pass the schema in info dir's private pointerJames Morse1-13/+25
Many of resctrl's per-schema files return a value from struct rdt_resource, which they take as their 'priv' pointer. Moving properties that resctrl exposes to user-space into the core 'fs' code, (e.g. the name of the schema), means some of the functions that back the filesystem need the schema struct (to where the properties are moved), but currently take struct rdt_resource. For example, once the CDP resources are merged, struct rdt_resource no longer reflects all the properties of the schema. For the info dirs that represent a control, the information needed will be accessed via struct resctrl_schema, as this is how the resource is being used. For the monitors, its still struct rdt_resource as the monitors aren't described as schema. This difference means the type of the private pointers varies between control and monitor info dirs. Change the 'priv' pointer to point to struct resctrl_schema for the per-schema files that represent a control. The type can be determined from the fflags field. If the flags are RF_MON_INFO, its a struct rdt_resource. If the flags are RF_CTRL_INFO, its a struct resctrl_schema. No entry in res_common_files[] has both flags. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-5-james.morse@arm.com
2021-08-11x86/resctrl: Add a separate schema list for resctrlJames Morse1-1/+42
Resctrl exposes schemata to user-space, which allow the control values to be specified for a group of tasks. User-visible properties of the interface, (such as the schemata names and how the values are parsed) are rooted in a struct provided by the architecture code. (struct rdt_hw_resource). Once a second architecture uses resctrl, this would allow user-visible properties to diverge between architectures. These properties should come from the resctrl code that will be common to all architectures. Resctrl has no per-schema structure, only struct rdt_{hw_,}resource. Create a struct resctrl_schema to hold the rdt_resource. Before a second architecture can be supported, this structure will also need to hold the schema name visible to user-space and the type of configuration values for resctrl. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-4-james.morse@arm.com
2021-08-11x86/resctrl: Split struct rdt_domainJames Morse1-10/+19
resctrl is the defacto Linux ABI for SoC resource partitioning features. To support it on another architecture, it needs to be abstracted from the features provided by Intel RDT and AMD PQoS, and moved to /fs/. struct rdt_domain contains a mix of architecture private details and properties of the filesystem interface user-space uses. Continue by splitting struct rdt_domain, into an architecture private 'hw' struct, which contains the common resctrl structure that would be used by any architecture. The hardware values in ctrl_val and mbps_val need to be accessed via helpers to allow another architecture to convert these into a different format if necessary. After this split, filesystem code paths touching a 'hw' struct indicates where an abstraction is needed. Splitting this structure only moves types around, and should not lead to any change in behaviour. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-3-james.morse@arm.com
2021-08-11x86/resctrl: Split struct rdt_resourceJames Morse1-30/+38
resctrl is the defacto Linux ABI for SoC resource partitioning features. To support it on another architecture, it needs to be abstracted from the features provided by Intel RDT and AMD PQoS, and moved to /fs/. struct rdt_resource contains a mix of architecture private details and properties of the filesystem interface user-space uses. Start by splitting struct rdt_resource, into an architecture private 'hw' struct, which contains the common resctrl structure that would be used by any architecture. The foreach helpers are most commonly used by the filesystem code, and should return the common resctrl structure. for_each_rdt_resource() is changed to walk the common structure in its parent arch private structure. Move as much of the structure as possible into the common structure in the core code's header file. The x86 hardware accessors remain part of the architecture private code, as do num_closid, mon_scale and mbm_width. mon_scale and mbm_width are used to detect overflow of the hardware counters, and convert them from their native size to bytes. Any cross-architecture abstraction should be in terms of bytes, making these properties private. The hardware's num_closid is kept in the private structure to force the filesystem code to use a helper to access it. MPAM would return a single value for the system, regardless of the resource. Using the helper prevents this field from being confused with the version of num_closid that is being exposed to user-space (added in a later patch). After this split, filesystem code touching a 'hw' struct indicates where an abstraction is needed. Splitting this structure only moves types around, and should not lead to any change in behaviour. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <jamie@nuviainc.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lkml.kernel.org/r/20210728170637.25610-2-james.morse@arm.com
2021-03-22x86: Fix various typos in comments, take #2Ingo Molnar1-1/+1
Fix another ~42 single-word typos in arch/x86/ code comments, missed a few in the first pass, in particular in .S files. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-kernel@vger.kernel.org
2021-03-18x86: Fix various typos in commentsIngo Molnar1-2/+2
Fix ~144 single-word typos in arch/x86/ code comments. Doing this in a single commit should reduce the churn. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-kernel@vger.kernel.org
2021-01-11x86/resctrl: Apply READ_ONCE/WRITE_ONCE to task_struct.{rmid,closid}Valentin Schneider1-5/+5
A CPU's current task can have its {closid, rmid} fields read locally while they are being concurrently written to from another CPU. This can happen anytime __resctrl_sched_in() races with either __rdtgroup_move_task() or rdt_move_group_tasks(). Prevent load / store tearing for those accesses by giving them the READ_ONCE() / WRITE_ONCE() treatment. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/9921fda88ad81afb9885b517fbe864a2bc7c35a9.1608243147.git.reinette.chatre@intel.com
2021-01-11x86/resctrl: Use task_curr() instead of task_struct->on_cpu to prevent ↵Reinette Chatre1-9/+5
unnecessary IPI James reported in [1] that there could be two tasks running on the same CPU with task_struct->on_cpu set. Using task_struct->on_cpu as a test if a task is running on a CPU may thus match the old task for a CPU while the scheduler is running and IPI it unnecessarily. task_curr() is the correct helper to use. While doing so move the #ifdef check of the CONFIG_SMP symbol to be a C conditional used to determine if this helper should be used to ensure the code is always checked for correctness by the compiler. [1] https://lore.kernel.org/lkml/a782d2f3-d2f6-795f-f4b1-9462205fd581@arm.com Reported-by: James Morse <james.morse@arm.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/e9e68ce1441a73401e08b641cc3b9a3cf13fe6d4.1608243147.git.reinette.chatre@intel.com
2021-01-08x86/resctrl: Don't move a task to the same resource groupFenghua Yu1-0/+7
Shakeel Butt reported in [1] that a user can request a task to be moved to a resource group even if the task is already in the group. It just wastes time to do the move operation which could be costly to send IPI to a different CPU. Add a sanity check to ensure that the move operation only happens when the task is not already in the resource group. [1] https://lore.kernel.org/lkml/CALvZod7E9zzHwenzf7objzGKsdBmVwTgEJ0nPgs0LUFU3SN5Pw@mail.gmail.com/ Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Reported-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/962ede65d8e95be793cb61102cca37f7bb018e66.1608243147.git.reinette.chatre@intel.com
2021-01-08x86/resctrl: Use an IPI instead of task_work_add() to update PQR_ASSOC MSRFenghua Yu1-69/+43
Currently, when moving a task to a resource group the PQR_ASSOC MSR is updated with the new closid and rmid in an added task callback. If the task is running, the work is run as soon as possible. If the task is not running, the work is executed later in the kernel exit path when the kernel returns to the task again. Updating the PQR_ASSOC MSR as soon as possible on the CPU a moved task is running is the right thing to do. Queueing work for a task that is not running is unnecessary (the PQR_ASSOC MSR is already updated when the task is scheduled in) and causing system resource waste with the way in which it is implemented: Work to update the PQR_ASSOC register is queued every time the user writes a task id to the "tasks" file, even if the task already belongs to the resource group. This could result in multiple pending work items associated with a single task even if they are all identical and even though only a single update with most recent values is needed. Specifically, even if a task is moved between different resource groups while it is sleeping then it is only the last move that is relevant but yet a work item is queued during each move. This unnecessary queueing of work items could result in significant system resource waste, especially on tasks sleeping for a long time. For example, as demonstrated by Shakeel Butt in [1] writing the same task id to the "tasks" file can quickly consume significant memory. The same problem (wasted system resources) occurs when moving a task between different resource groups. As pointed out by Valentin Schneider in [2] there is an additional issue with the way in which the queueing of work is done in that the task_struct update is currently done after the work is queued, resulting in a race with the register update possibly done before the data needed by the update is available. To solve these issues, update the PQR_ASSOC MSR in a synchronous way right after the new closid and rmid are ready during the task movement, only if the task is running. If a moved task is not running nothing is done since the PQR_ASSOC MSR will be updated next time the task is scheduled. This is the same way used to update the register when tasks are moved as part of resource group removal. [1] https://lore.kernel.org/lkml/CALvZod7E9zzHwenzf7objzGKsdBmVwTgEJ0nPgs0LUFU3SN5Pw@mail.gmail.com/ [2] https://lore.kernel.org/lkml/20201123022433.17905-1-valentin.schneider@arm.com [ bp: Massage commit message and drop the two update_task_closid_rmid() variants. ] Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Reported-by: Shakeel Butt <shakeelb@google.com> Reported-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: James Morse <james.morse@arm.com> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/17aa2fb38fc12ce7bb710106b3e7c7b45acb9e94.1608243147.git.reinette.chatre@intel.com
2020-12-15Merge tag 'x86_cache_for_v5.11' of ↵Linus Torvalds1-12/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cache resource control updates from Borislav Petkov: - add logic to correct MBM total and local values fixing errata SKX99 and BDF102 (Fenghua Yu) - cleanups * tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Clean up unused function parameter in rmdir path x86/resctrl: Constify kernfs_ops x86/resctrl: Correct MBM total and local values Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
2020-12-01x86/resctrl: Clean up unused function parameter in rmdir pathXiaochen Shen1-10/+7
Commit fd8d9db3559a ("x86/resctrl: Remove superfluous kernfs_get() calls to prevent refcount leak") removed superfluous kernfs_get() calls in rdtgroup_ctrl_remove() and rdtgroup_rmdir_ctrl(). That change resulted in an unused function parameter to these two functions. Clean up the unused function parameter in rdtgroup_ctrl_remove(), rdtgroup_rmdir_mon() and their callers rdtgroup_rmdir_ctrl() and rdtgroup_rmdir(). Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1606759618-13181-1-git-send-email-xiaochen.shen@intel.com
2020-12-01Merge tag 'v5.10-rc6' into x86/cacheBorislav Petkov1-39/+26
Merge -rc6 tag to pick up dependent changes. Signed-off-by: Borislav Petkov <bp@suse.de>
2020-12-01x86/resctrl: Fix AMD L3 QOS CDP enable/disableBabu Moger1-2/+7
When the AMD QoS feature CDP (code and data prioritization) is enabled or disabled, the CDP bit in MSR 0000_0C81 is written on one of the CPUs in an L3 domain (core complex). That is not correct - the CDP bit needs to be updated on all the logical CPUs in the domain. This was not spelled out clearly in the spec earlier. The specification has been updated and the updated document, "AMD64 Technology Platform Quality of Service Extensions Publication # 56375 Revision: 1.02 Issue Date: October 2020" is available now. Refer the section: Code and Data Prioritization. Fix the issue by adding a new flag arch_has_per_cpu_cfg in rdt_cache data structure. The documentation can be obtained at: https://developer.amd.com/wp-content/resources/56375.pdf Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 [ bp: Massage commit message. ] Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature") Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/160675180380.15628.3309402017215002347.stgit@bmoger-ubuntu
2020-11-24x86/resctrl: Add necessary kernfs_put() calls to prevent refcount leakXiaochen Shen1-7/+25
On resource group creation via a mkdir an extra kernfs_node reference is obtained by kernfs_get() to ensure that the rdtgroup structure remains accessible for the rdtgroup_kn_unlock() calls where it is removed on deletion. Currently the extra kernfs_node reference count is only dropped by kernfs_put() in rdtgroup_kn_unlock() while the rdtgroup structure is removed in a few other locations that lack the matching reference drop. In call paths of rmdir and umount, when a control group is removed, kernfs_remove() is called to remove the whole kernfs nodes tree of the control group (including the kernfs nodes trees of all child monitoring groups), and then rdtgroup structure is freed by kfree(). The rdtgroup structures of all child monitoring groups under the control group are freed by kfree() in free_all_child_rdtgrp(). Before calling kfree() to free the rdtgroup structures, the kernfs node of the control group itself as well as the kernfs nodes of all child monitoring groups still take the extra references which will never be dropped to 0 and the kernfs nodes will never be freed. It leads to reference count leak and kernfs_node_cache memory leak. For example, reference count leak is observed in these two cases: (1) mount -t resctrl resctrl /sys/fs/resctrl mkdir /sys/fs/resctrl/c1 mkdir /sys/fs/resctrl/c1/mon_groups/m1 umount /sys/fs/resctrl (2) mkdir /sys/fs/resctrl/c1 mkdir /sys/fs/resctrl/c1/mon_groups/m1 rmdir /sys/fs/resctrl/c1 The same reference count leak issue also exists in the error exit paths of mkdir in mkdir_rdt_prepare() and rdtgroup_mkdir_ctrl_mon(). Fix this issue by following changes to make sure the extra kernfs_node reference on rdtgroup is dropped before freeing the rdtgroup structure. (1) Introduce rdtgroup removal helper rdtgroup_remove() to wrap up kernfs_put() and kfree(). (2) Call rdtgroup_remove() in rdtgroup removal path where the rdtgroup structure is about to be freed by kfree(). (3) Call rdtgroup_remove() or kernfs_put() as appropriate in the error exit paths of mkdir where an extra reference is taken by kernfs_get(). Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1604085088-31707-1-git-send-email-xiaochen.shen@intel.com
2020-11-24x86/resctrl: Remove superfluous kernfs_get() calls to prevent refcount leakXiaochen Shen1-33/+2
Willem reported growing of kernfs_node_cache entries in slabtop when repeatedly creating and removing resctrl subdirectories as well as when repeatedly mounting and unmounting the resctrl filesystem. On resource group (control as well as monitoring) creation via a mkdir an extra kernfs_node reference is obtained to ensure that the rdtgroup structure remains accessible for the rdtgroup_kn_unlock() calls where it is removed on deletion. The kernfs_node reference count is dropped by kernfs_put() in rdtgroup_kn_unlock(). With the above explaining the need for one kernfs_get()/kernfs_put() pair in resctrl there are more places where a kernfs_node reference is obtained without a corresponding release. The excessive amount of reference count on kernfs nodes will never be dropped to 0 and the kernfs nodes will never be freed in the call paths of rmdir and umount. It leads to reference count leak and kernfs_node_cache memory leak. Remove the superfluous kernfs_get() calls and expand the existing comments surrounding the remaining kernfs_get()/kernfs_put() pair that remains in use. Superfluous kernfs_get() calls are removed from two areas: (1) In call paths of mount and mkdir, when kernfs nodes for "info", "mon_groups" and "mon_data" directories and sub-directories are created, the reference count of newly created kernfs node is set to 1. But after kernfs_create_dir() returns, superfluous kernfs_get() are called to take an additional reference. (2) kernfs_get() calls in rmdir call paths. Fixes: 17eafd076291 ("x86/intel_rdt: Split resource group removal in two") Fixes: 4af4a88e0c92 ("x86/intel_rdt/cqm: Add mount,umount support") Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: d89b7379015f ("x86/intel_rdt/cqm: Add mon_data") Fixes: c7d9aac61311 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring") Fixes: 5dc1d5c6bac2 ("x86/intel_rdt: Simplify info and base file lists") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Fixes: 4e978d06dedb ("x86/intel_rdt: Add "info" files to resctrl file system") Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Willem de Bruijn <willemb@google.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1604085053-31639-1-git-send-email-xiaochen.shen@intel.com
2020-11-19x86/resctrl: Constify kernfs_opsRikard Falkeborn1-2/+2
The only usage of the kf_ops field in the rftype struct is to pass it as argument to __kernfs_create_file(), which accepts a pointer to const. Make it a pointer to const. This makes it possible to make rdtgroup_kf_single_ops and kf_mondata_ops const, which allows the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/20201110230228.801785-1-rikard.falkeborn@gmail.com
2020-10-18task_work: cleanup notification modesJens Axboe1-1/+1
A previous commit changed the notification mode from true/false to an int, allowing notify-no, notify-yes, or signal-notify. This was backwards compatible in the sense that any existing true/false user would translate to either 0 (on notification sent) or 1, the latter which mapped to TWA_RESUME. TWA_SIGNAL was assigned a value of 2. Clean this up properly, and define a proper enum for the notification mode. Now we have: - TWA_NONE. This is 0, same as before the original change, meaning no notification requested. - TWA_RESUME. This is 1, same as before the original change, meaning that we use TIF_NOTIFY_RESUME. - TWA_SIGNAL. This uses TIF_SIGPENDING/JOBCTL_TASK_WORK for the notification. Clean up all the callers, switching their 0/1/false/true to using the appropriate TWA_* mode for notifications. Fixes: e91b48162332 ("task_work: teach task_work_add() to do signal_wake_up()") Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-26x86/resctrl: Enable user to view thread or core throttling modeFenghua Yu1-1/+52
Early Intel hardware implementations of Memory Bandwidth Allocation (MBA) could only control bandwidth at the processor core level. This meant that when two processes with different bandwidth allocations ran simultaneously on the same core the hardware had to resolve this difference. It did so by applying the higher throttling value (lower bandwidth) to both processes. Newer implementations can apply different throttling values to each thread on a core. Introduce a new resctrl file, "thread_throttle_mode", on Intel systems that shows to the user how throttling values are allocated, per-core or per-thread. On systems that support per-core throttling, the file will display "max". On newer systems that support per-thread throttling, the file will display "per-thread". AMD confirmed in [1] that AMD bandwidth allocation is already at thread level but that the AMD implementation does not use a memory delay throttle mode. So to avoid confusion the thread throttling mode would be UNDEFINED on AMD systems and the "thread_throttle_mode" file will not be visible. Originally-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1598296281-127595-3-git-send-email-fenghua.yu@intel.com Link: [1] https://lore.kernel.org/lkml/18d277fd-6523-319c-d560-66b63ff606b8@amd.com
2020-08-19x86/resctrl: Use is_closid_match() in more placesJames Morse1-16/+14
rdtgroup_tasks_assigned() and show_rdt_tasks() loop over threads testing for a CTRL/MON group match by closid/rmid with the provided rdtgrp. Further down the file are helpers to do this, move these further up and make use of them here. These helpers additionally check for alloc/mon capable. This is harmless as rdtgroup_mkdir() tests these capable flags before allowing the config directories to be created. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/20200708163929.2783-7-james.morse@arm.com
2020-08-18x86/resctrl: Fix stale commentJames Morse1-1/+1
The comment in rdtgroup_init() refers to the non existent function rdt_mount(), which has now been renamed rdt_get_tree(). Fix the comment. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/20200708163929.2783-4-james.morse@arm.com
2020-06-17x86/resctrl: Fix a NULL vs IS_ERR() static checker warning in rdt_cdp_peer_get()Dan Carpenter1-0/+1
The callers don't expect *d_cdp to be set to an error pointer, they only check for NULL. This leads to a static checker warning: arch/x86/kernel/cpu/resctrl/rdtgroup.c:2648 __init_one_rdt_domain() warn: 'd_cdp' could be an error pointer This would not trigger a bug in this specific case because __init_one_rdt_domain() calls it with a valid domain that would not have a negative id and thus not trigger the return of the ERR_PTR(). If this was a negative domain id then the call to rdt_find_domain() in domain_add_cpu() would have returned the ERR_PTR() much earlier and the creation of the domain with an invalid id would have been prevented. Even though a bug is not triggered currently the right and safe thing to do is to set the pointer to NULL because that is what can be checked for when the caller is handling the CDP and non-CDP cases. Fixes: 52eb74339a62 ("x86/resctrl: Fix rdt_find_domain() return value and checks") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Acked-by: Fenghua Yu <fenghua.yu@intel.com> Link: https://lkml.kernel.org/r/20200602193611.GA190851@mwanda
2020-06-09mmap locking API: convert mmap_sem commentsMichel Lespinasse1-3/+3
Convert comments that reference mmap_sem to reference mmap_lock instead. [akpm@linux-foundation.org: fix up linux-next leftovers] [akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil] [akpm@linux-foundation.org: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-06x86/resctrl: Maintain MBM counter width per resourceReinette Chatre1-1/+1
The original Memory Bandwidth Monitoring (MBM) architectural definition defines counters of up to 62 bits in the IA32_QM_CTR MSR, and the first-generation MBM implementation uses 24 bit counters. Software is required to poll at 1 second or faster to ensure that data is retrieved before a counter rollover occurs more than once under worst conditions. As system bandwidths scale the software requirement is maintained with the introduction of a per-resource enumerable MBM counter width. In preparation for supporting hardware with an enumerable MBM counter width the current globally static MBM counter width is moved to a per-resource MBM counter width. Currently initialized to 24 always to result in no functional change. In essence there is one function, mbm_overflow_count() that needs to know the counter width to handle rollovers. The static value used within mbm_overflow_count() will be replaced with a value discovered from the hardware. Support for learning the MBM counter width from hardware is added in the change that follows. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/e36743b9800f16ce600f86b89127391f61261f23.1588715690.git.reinette.chatre@intel.com
2020-05-06x86/resctrl: Rename asm/resctrl_sched.h to asm/resctrl.hReinette Chatre1-1/+1
asm/resctrl_sched.h is dedicated to the code used for configuration of the CPU resource control state when a task is scheduled. Rename resctrl_sched.h to resctrl.h in preparation of additions that will no longer make this file dedicated to work done during scheduling. No functional change. Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/6914e0ef880b539a82a6d889f9423496d471ad1d.1588715690.git.reinette.chatre@intel.com
2020-04-17x86/resctrl: Preserve CDP enable over CPU hotplugJames Morse1-0/+13
Resctrl assumes that all CPUs are online when the filesystem is mounted, and that CPUs remember their CDP-enabled state over CPU hotplug. This goes wrong when resctrl's CDP-enabled state changes while all the CPUs in a domain are offline. When a domain comes online, enable (or disable!) CDP to match resctrl's current setting. Fixes: 5ff193fbde20 ("x86/intel_rdt: Add basic resctrl filesystem support") Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200221162105.154163-1-james.morse@arm.com
2020-04-17x86/resctrl: Fix invalid attempt at removing the default resource groupReinette Chatre1-1/+2
The default resource group ("rdtgroup_default") is associated with the root of the resctrl filesystem and should never be removed. New resource groups can be created as subdirectories of the resctrl filesystem and they can be removed from user space. There exists a safeguard in the directory removal code (rdtgroup_rmdir()) that ensures that only subdirectories can be removed by testing that the directory to be removed has to be a child of the root directory. A possible deadlock was recently fixed with 334b0f4e9b1b ("x86/resctrl: Fix a deadlock due to inaccurate reference"). This fix involved associating the private data of the "mon_groups" and "mon_data" directories to the resource group to which they belong instead of NULL as before. A consequence of this change was that the original safeguard code preventing removal of "mon_groups" and "mon_data" found in the root directory failed resulting in attempts to remove the default resource group that ends in a BUG: kernel BUG at mm/slub.c:3969! invalid opcode: 0000 [#1] SMP PTI Call Trace: rdtgroup_rmdir+0x16b/0x2c0 kernfs_iop_rmdir+0x5c/0x90 vfs_rmdir+0x7a/0x160 do_rmdir+0x17d/0x1e0 do_syscall_64+0x55/0x1d0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fix this by improving the directory removal safeguard to ensure that subdirectories of the resctrl root directory can only be removed if they are a child of the resctrl filesystem's root _and_ not associated with the default resource group. Fixes: 334b0f4e9b1b ("x86/resctrl: Fix a deadlock due to inaccurate reference") Reported-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/884cbe1773496b5dbec1b6bd11bb50cffa83603d.1584461853.git.reinette.chatre@intel.com
2020-02-09Merge branch 'merge.nfs-fs_parse.1' of ↵Linus Torvalds1-8/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs file system parameter updates from Al Viro: "Saner fs_parser.c guts and data structures. The system-wide registry of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is the horror switch() in fs_parse() that would have to grow another case every time something got added to that system-wide registry. New syntax types can be added by filesystems easily now, and their namespace is that of functions - not of system-wide enum members. IOW, they can be shared or kept private and if some turn out to be widely useful, we can make them common library helpers, etc., without having to do anything whatsoever to fs_parse() itself. And we already get that kind of requests - the thing that finally pushed me into doing that was "oh, and let's add one for timeouts - things like 15s or 2h". If some filesystem really wants that, let them do it. Without somebody having to play gatekeeper for the variants blessed by direct support in fs_parse(), TYVM. Quite a bit of boilerplate is gone. And IMO the data structures make a lot more sense now. -200LoC, while we are at it" * 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits) tmpfs: switch to use of invalfc() cgroup1: switch to use of errorfc() et.al. procfs: switch to use of invalfc() hugetlbfs: switch to use of invalfc() cramfs: switch to use of errofc() et.al. gfs2: switch to use of errorfc() et.al. fuse: switch to use errorfc() et.al. ceph: use errorfc() and friends instead of spelling the prefix out prefix-handling analogues of errorf() and friends turn fs_param_is_... into functions fs_parse: handle optional arguments sanely fs_parse: fold fs_parameter_desc/fs_parameter_spec fs_parser: remove fs_parameter_description name field add prefix to fs_context->log ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log new primitive: __fs_parse() switch rbd and libceph to p_log-based primitives struct p_log, variants of warnf() et.al. taking that one instead teach logfc() to handle prefices, give it saner calling conventions get rid of cg_invalf() ...
2020-02-07fs_parse: fold fs_parameter_desc/fs_parameter_specAl Viro1-7/+3
The former contains nothing but a pointer to an array of the latter... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07fs_parser: remove fs_parameter_description name fieldEric Sandeen1-1/+0
Unused now. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-31Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-23/+25
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - three fixes and a cleanup for the resctrl code - a HyperV fix - a fix to /proc/kcore contents in live debugging sessions - a fix for the x86 decoder opcode map" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/decoder: Add TEST opcode to Group3-2 x86/resctrl: Clean up unused function parameter in mkdir path x86/resctrl: Fix a deadlock due to inaccurate reference x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup x86/resctrl: Fix use-after-free when deleting resource groups x86/hyper-v: Add "polling" bit to hv_synic_sint x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
2020-01-28Merge branch 'x86-cache-for-linus' of ↵Linus Torvalds1-0/+90
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Ingo Molnar: "The main change in this tree is the extension of the resctrl procfs ABI with a new file that helps tooling to navigate from tasks back to resctrl groups: /proc/{pid}/cpu_resctrl_groups. Also fix static key usage for certain feature combinations and simplify the task exit resctrl case" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Add task resctrl information display x86/resctrl: Check monitoring static key in the MBM overflow handler x86/resctrl: Do not reconfigure exiting tasks