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2025-11-21x86,fs/resctrl: Implement "io_alloc" enable/disable handlersBabu Moger1-0/+21
"io_alloc" is the generic name of the new resctrl feature that enables system software to configure the portion of cache allocated for I/O traffic. On AMD systems, "io_alloc" resctrl feature is backed by AMD's L3 Smart Data Cache Injection Allocation Enforcement (SDCIAE). Introduce the architecture-specific functions that resctrl fs should call to enable, disable, or check status of the "io_alloc" feature. Change SDCIAE state by setting (to enable) or clearing (to disable) bit 1 of MSR_IA32_L3_QOS_EXT_CFG on all logical processors within the cache domain. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/9e9070100c320eab5368e088a3642443dee95ed7.1762995456.git.babu.moger@amd.com
2025-11-21x86,fs/resctrl: Detect io_alloc featureBabu Moger1-0/+3
AMD's SDCIAE (SDCI Allocation Enforcement) PQE feature enables system software to control the portions of L3 cache used for direct insertion of data from I/O devices into the L3 cache. Introduce a generic resctrl cache resource property "io_alloc_capable" as the first part of the new "io_alloc" resctrl feature that will support AMD's SDCIAE. Any architecture can set a cache resource as "io_alloc_capable" if a portion of the cache can be allocated for I/O traffic. Set the "io_alloc_capable" property for the L3 cache resource on x86 (AMD) systems that support SDCIAE. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/df85a9a6081674fd3ef6b4170920485512ce2ded.1762995456.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce mbm_assign_on_mkdir to enable assignments on mkdirBabu Moger1-0/+3
The "mbm_event" counter assignment mode allows users to assign a hardware counter to an RMID, event pair and monitor the bandwidth as long as it is assigned. Introduce a user-configurable option that determines if a counter will automatically be assigned to an RMID, event pair when its associated monitor group is created via mkdir. Accessible when "mbm_event" counter assignment mode is enabled. Suggested-by: Peter Newman <peternewman@google.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce counter ID read, reset calls in mbm_event modeBabu Moger1-0/+38
When supported, "mbm_event" counter assignment mode allows users to assign a hardware counter to an RMID, event pair and monitor the bandwidth usage as long as it is assigned. The hardware continues to track the assigned counter until it is explicitly unassigned by the user. Introduce the architecture calls resctrl_arch_cntr_read() and resctrl_arch_reset_cntr() to read and reset event counters when "mbm_event" mode is supported. Function names match existing resctrl_arch_rmid_read() and resctrl_arch_reset_rmid(). Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15x86,fs/resctrl: Implement resctrl_arch_config_cntr() to assign a counter ↵Babu Moger1-0/+19
with ABMC The ABMC feature allows users to assign a hardware counter to an RMID, event pair and monitor bandwidth usage as long as it is assigned. The hardware continues to track the assigned counter until it is explicitly unassigned by the user. Implement an x86 architecture-specific handler to configure a counter. This architecture specific handler is called by resctrl fs when a counter is assigned or unassigned as well as when an already assigned counter's configuration should be updated. Configure counters by writing to the L3_QOS_ABMC_CFG MSR, specifying the counter ID, bandwidth source (RMID), and event configuration. The ABMC feature details are documented in APM [1] available from [2]. [1] AMD64 Architecture Programmer's Manual Volume 2: System Programming Publication # 24593 Revision 3.41 section 19.3.3.3 Assignable Bandwidth Monitoring (ABMC). Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 # [2]
2025-09-15fs/resctrl: Introduce event configuration field in struct mon_evtBabu Moger1-0/+2
When supported, mbm_event counter assignment mode allows the user to configure events to track specific types of memory transactions. Introduce an evt_cfg field in struct mon_evt to define the type of memory transactions tracked by a monitoring event. Also add a helper function to get the evt_cfg value. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce mbm_cntr_cfg to track assignable counters per domainBabu Moger1-0/+15
The "mbm_event" counter assignment mode allows users to assign a hardware counter to an RMID, event pair and monitor bandwidth usage as long as it is assigned. The hardware continues to track the assigned counter until it is explicitly unassigned by the user. Counters are assigned/unassigned at monitoring domain level. Manage a monitoring domain's hardware counters using a per monitoring domain array of struct mbm_cntr_cfg that is indexed by the hardware counter ID. A hardware counter's configuration contains the MBM event ID and points to the monitoring group that it is assigned to, with a NULL pointer meaning that the hardware counter is available for assignment. There is no direct way to determine which hardware counters are assigned to a particular monitoring group. Check every entry of every hardware counter configuration array in every monitoring domain to query which MBM events of a monitoring group is tracked by hardware. Such queries are acceptable because of a very small number of assignable counters (32 to 64). Suggested-by: Peter Newman <peternewman@google.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15x86/resctrl: Add support to enable/disable AMD ABMC featureBabu Moger1-0/+20
Add the functionality to enable/disable the AMD ABMC feature. The AMD ABMC feature is enabled by setting enabled bit(0) in the L3_QOS_EXT_CFG MSR. When the state of ABMC is changed, the MSR needs to be updated on all the logical processors in the QOS Domain. Hardware counters will reset when ABMC state is changed. [ bp: Massage commit message. ] Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 # [2]
2025-09-15x86,fs/resctrl: Detect Assignable Bandwidth Monitoring feature detailsBabu Moger1-0/+4
ABMC feature details are reported via CPUID Fn8000_0020_EBX_x5. Bits Description 15:0 MAX_ABMC Maximum Supported Assignable Bandwidth Monitoring Counter ID + 1 The ABMC feature details are documented in APM [1] available from [2]. [1] AMD64 Architecture Programmer's Manual Volume 2: System Programming Publication # 24593 Revision 3.41 section 19.3.3.3 Assignable Bandwidth Monitoring (ABMC). Detect the feature and number of assignable counters supported. For backward compatibility, upon detecting the assignable counter feature, enable the mbm_total_bytes and mbm_local_bytes events that users are familiar with as part of original L3 MBM support. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 # [2]
2025-09-15x86,fs/resctrl: Consolidate monitoring related data from rdt_resourceBabu Moger1-5/+13
The cache allocation and memory bandwidth allocation feature properties are consolidated into struct resctrl_cache and struct resctrl_membw respectively. In preparation for more monitoring properties that will clobber the existing resource struct more, re-organize the monitoring specific properties to also be in a separate structure. Also convert "bandwidth sources" terminology to "memory transactions" to have consistency within resctrl for related monitoring features. [ bp: Massage commit message. ] Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15x86,fs/resctrl: Prepare for more monitor eventsTony Luck1-4/+19
There's a rule in computer programming that objects appear zero, once, or many times. So code accordingly. There are two MBM events and resctrl is coded with a lot of if (local) do one thing if (total) do a different thing Change the rdt_mon_domain and rdt_hw_mon_domain structures to hold arrays of pointers to per event data instead of explicit fields for total and local bandwidth. Simplify by coding for many events using loops on which are enabled. Move resctrl_is_mbm_event() to <linux/resctrl.h> so it can be used more widely. Also provide a for_each_mbm_event_id() helper macro. Cleanup variable names in functions touched to consistently use "eventid" for those with type enum resctrl_event_id. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15x86,fs/resctrl: Replace architecture event enabled checksTony Luck1-0/+2
The resctrl file system now has complete knowledge of the status of every event. So there is no need for per-event function calls to check. Replace each of the resctrl_arch_is_{event}enabled() calls with resctrl_is_mon_event_enabled(QOS_{EVENT}). No functional change. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15x86,fs/resctrl: Consolidate monitor event descriptionsTony Luck1-2/+2
There are currently only three monitor events, all associated with the RDT_RESOURCE_L3 resource. Growing support for additional events will be easier with some restructuring to have a single point in file system code where all attributes of all events are defined. Place all event descriptions into an array mon_event_all[]. Doing this has the beneficial side effect of removing the need for rdt_resource::evt_list. Add resctrl_event_id::QOS_FIRST_EVENT for a lower bound on range checks for event ids and as the starting index to scan mon_event_all[]. Drop the code that builds evt_list and change the two places where the list is scanned to scan mon_event_all[] instead using a new helper macro for_each_mon_event(). Architecture code now informs file system code which events are available with resctrl_enable_mon_event(). Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-06-16x86,fs/resctrl: Remove inappropriate references to cacheinfo in the resctrl ↵Qinyun Tan1-2/+2
subsystem In the resctrl subsystem's Sub-NUMA Cluster (SNC) mode, the rdt_mon_domain structure representing a NUMA node relies on the cacheinfo interface (rdt_mon_domain::ci) to store L3 cache information (e.g., shared_cpu_map) for monitoring. The L3 cache information of a SNC NUMA node determines which domains are summed for the "top level" L3-scoped events. rdt_mon_domain::ci is initialized using the first online CPU of a NUMA node. When this CPU goes offline, its shared_cpu_map is cleared to contain only the offline CPU itself. Subsequently, attempting to read counters via smp_call_on_cpu(offline_cpu) fails (and error ignored), returning zero values for "top-level events" without any error indication. Replace the cacheinfo references in struct rdt_mon_domain and struct rmid_read with the cacheinfo ID (a unique identifier for the L3 cache). rdt_domain_hdr::cpu_mask contains the online CPUs associated with that domain. When reading "top-level events", select a CPU from rdt_domain_hdr::cpu_mask and utilize its L3 shared_cpu_map to determine valid CPUs for reading RMID counter via the MSR interface. Considering all CPUs associated with the L3 cache improves the chances of picking a housekeeping CPU on which the counter reading work can be queued, avoiding an unnecessary IPI. Fixes: 328ea68874642 ("x86/resctrl: Prepare for new Sub-NUMA Cluster (SNC) monitor files") Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250530182053.37502-2-qinyuntan@linux.alibaba.com
2025-05-16x86/resctrl: Move pseudo lock prototypes to include/linux/resctrl.hJames Morse1-0/+13
The resctrl pseudo-lock feature allows an architecture to allocate data into particular cache portions, which are then treated as reserved to avoid that data ever being evicted. Setting this up is deeply architecture specific as it involves disabling prefetchers etc. It is not possible to support this kind of feature on arm64. Risc-V is assumed to be the same. The prototypes for the architecture code were added to x86's asm/resctrl.h, with other architectures able to provide stubs for their architecture. This forces other architectures to provide identical stubs. Move the prototypes and stubs to linux/resctrl.h, and switch between them using the existing Kconfig symbol. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-20-james.morse@arm.com
2025-05-16x86/resctrl: Move enum resctrl_event_id to resctrl.hJames Morse1-0/+10
resctrl_types.h contains common types and constants to enable architectures to use these types in their definitions within asm/resctrl.h. enum resctrl_event_id was placed in resctrl_types.h for resctrl_arch_get_cdp_enabled() and resctrl_arch_set_cdp_enabled(), but these two functions are no longer inlined by any architecture. Move enum resctrl_event_id to resctrl.h. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-18-james.morse@arm.com
2025-05-16x86/resctrl: Move the filesystem bits to headers visible to fs/resctrlJames Morse1-0/+3
Once the filesystem parts of resctrl move to fs/resctrl, it cannot rely on definitions in x86's internal.h. Move definitions in internal.h that need to be shared between the filesystem and architecture code to header files that fs/resctrl can include. Doing this separately means the filesystem code only moves between files of the same name, instead of having these changes mixed in too. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-17-james.morse@arm.com
2025-05-16fs/resctrl: Add boiler plate for external resctrl codeJames Morse1-0/+4
Add Makefile and Kconfig for fs/resctrl. Add ARCH_HAS_CPU_RESCTRL for the common parts of the resctrl interface and make X86_CPU_RESCTRL select this. Adding an include of asm/resctrl.h to linux/resctrl.h allows the /fs/resctrl files to switch over to using this header instead. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-16-james.morse@arm.com
2025-05-15x86/resctrl: Drop __init/__exit on assorted symbolsJames Morse1-3/+3
Because ARM's MPAM controls are probed using MMIO, resctrl can't be initialised until enough CPUs are online to have determined the system-wide supported num_closid. Arm64 also supports 'late onlined secondaries', where only a subset of CPUs are online during boot. These two combine to mean the MPAM driver may not be able to initialise resctrl until user-space has brought 'enough' CPUs online. To allow MPAM to initialise resctrl after __init text has been free'd, remove all the __init markings from resctrl. The existing __exit markings cause these functions to be removed by the linker as it has never been possible to build resctrl as a module. MPAM has an error interrupt which causes the driver to reset and disable itself. Remove the __exit markings to allow the MPAM driver to tear down resctrl when an error occurs. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-10-james.morse@arm.com
2025-03-12x86/resctrl: Move get_config_index() to a headerJames Morse1-0/+15
get_config_index() is used by the architecture specific code to map a CLOSID+type pair to an index in the configuration arrays. MPAM needs to do this too to preserve the ABI to user-space, there is no reason to do it differently. Move the helper to a header file to allow all architectures that either use or emulate CDP to use the same pattern of CLOSID values. Moving this to a header file means it must be marked inline, which matches the existing compiler choice for this static function. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-30-james.morse@arm.com
2025-03-12x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plrJames Morse1-0/+39
resctrl_arch_pseudo_lock_fn() has architecture specific behaviour, and takes a struct rdtgroup as an argument. After the filesystem code moves to /fs/, the definition of struct rdtgroup will not be available to the architecture code. The only reason resctrl_arch_pseudo_lock_fn() wants the rdtgroup is for the CLOSID. Embed that in the pseudo_lock_region as a closid, and move the definition of struct pseudo_lock_region to resctrl.h. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-27-james.morse@arm.com
2025-03-12x86/resctrl: Move mbm_cfg_mask to struct rdt_resourceJames Morse1-0/+3
The mbm_cfg_mask field lists the bits that user-space can set when configuring an event. This value is output via the last_cmd_status file. Once the filesystem parts of resctrl are moved to live in /fs/, the struct rdt_hw_resource is inaccessible to the filesystem code. Because this value is output to user-space, it has to be accessible to the filesystem code. Move it to struct rdt_resource. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-23-james.morse@arm.com
2025-03-12x86/resctrl: Change mon_event_config_{read,write}() to be arch helpersJames Morse1-0/+31
mon_event_config_{read,write}() are called via IPI and access model specific registers to do their work. To support another architecture, this needs abstracting. Rename mon_event_config_{read,write}() to have a "resctrl_arch_" prefix, and move their struct mon_config_info parameter into <linux/resctrl.h>. This allows another architecture to supply an implementation of these. As struct mon_config_info is now exposed globally, give it a 'resctrl_' prefix. MPAM systems need access to the domain to do this work, add the resource and domain to struct resctrl_mon_config_info. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-21-james.morse@arm.com
2025-03-12x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMECJames Morse1-0/+2
When BMEC is supported the resctrl event can be configured in a number of ways. This depends on architecture support. rdt_get_mon_l3_config() modifies the struct mon_evt and calls resctrl_file_fflags_init() to create the files that allow the configuration. Splitting this into separate architecture and filesystem parts would require the struct mon_evt and resctrl_file_fflags_init() to be exposed. Instead, add resctrl_arch_is_evt_configurable(), and use this from resctrl_mon_resource_init() to initialise struct mon_evt and call resctrl_file_fflags_init(). resctrl_arch_is_evt_configurable() calls rdt_cpu_has() so it doesn't obviously benefit from being inlined. Putting it in core.c will allow rdt_cpu_has() to eventually become static. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-20-james.morse@arm.com
2025-03-12x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkersJames Morse1-0/+18
The for_each_*_rdt_resource() helpers walk the architecture's array of structures, using the resctrl visible part as an iterator. These became over-complex when the structures were split into a filesystem and architecture-specific struct. This approach avoided the need to touch every call site, and was done before there was a helper to retrieve a resource by rid. Once the filesystem parts of resctrl are moved to /fs/, both the arch's resource array, and the definition of those structures is no longer accessible. To support resctrl, each architecture would have to provide equally complex macros. Rewrite the macro to make use of resctrl_arch_get_resource(), and move these to include/linux/resctrl.h so existing x86 arch code continues to use them. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-18-james.morse@arm.com
2025-03-12x86/resctrl: Add an arch helper to reset one resourceJames Morse1-0/+9
On umount(), resctrl resets each resource back to its default configuration. It only ever does this for all resources in one go. reset_all_ctrls() is architecture specific as it works with struct rdt_hw_resource. Make reset_all_ctrls() an arch helper that resets one resource. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-15-james.morse@arm.com
2025-03-12x86/resctrl: Move resctrl types to a separate headerJames Morse1-20/+1
When resctrl is fully factored into core and per-arch code, each arch will need to use some resctrl common definitions in order to define its own specializations and helpers. Following conventional practice, it would be desirable to put the dependent arch definitions in an <asm/resctrl.h> header that is included by the common <linux/resctrl.h> header. However, this can make it awkward to avoid a circular dependency between <linux/resctrl.h> and the arch header. To avoid such dependencies, move the affected common types and constants into a new header that does not need to depend on <linux/resctrl.h> or on the arch headers. The same logic applies to the monitor-configuration defines, move these too. Some kind of enumeration for events is needed between the filesystem and architecture code. Take the x86 definition as its convenient for x86. The definition of enum resctrl_event_id is needed to allow the architecture code to define resctrl_arch_mon_ctx_alloc() and resctrl_arch_mon_ctx_free(). The definition of enum resctrl_res_level is needed to allow the architecture code to define resctrl_arch_set_cdp_enabled() and resctrl_arch_get_cdp_enabled(). The bits for mbm_local_bytes_config et al are ABI, and must be the same on all architectures. These are documented in Documentation/arch/x86/resctrl.rst The maintainers entry for these headers was missed when resctrl.h was created. Add a wildcard entry to match both resctrl.h and resctrl_types.h. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-14-james.morse@arm.com
2025-03-12x86/resctrl: Move rdt_find_domain() to be visible to arch and fs codeJames Morse1-0/+14
rdt_find_domain() finds a domain given a resource and a cache-id. This is used by both the architecture code and the filesystem code. After the filesystem code moves to live in /fs/, this helper is either duplicated by all architectures, or needs exposing by the filesystem code. Add the declaration to the global header file. As it's now globally visible, and has only a handful of callers, swap the 'rdt' for 'resctrl'. Move the function to live with its caller in ctrlmondata.c as the filesystem code will not have anything corresponding to core.c. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-13-james.morse@arm.com
2025-03-12x86/resctrl: Expose resctrl fs's init function to the rest of the kernelJames Morse1-0/+3
rdtgroup_init() needs exposing to the rest of the kernel so that arch code can call it once it lives in core code. As this is one of the few functions exposed, rename it to have "resctrl" in the name. The same goes for the exit call. Rename x86's arch code init functions for RDT to have an arch prefix to make it clear these are part of the architecture code. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-12-james.morse@arm.com
2025-03-12x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()James Morse1-0/+22
update_cpu_closid_rmid() takes a struct rdtgroup as an argument, which it uses to update the local CPUs default pqr values. This is a problem once the resctrl parts move out to /fs/, as the arch code cannot poke around inside struct rdtgroup. Rename update_cpu_closid_rmid() as resctrl_arch_sync_cpus_defaults() to be used as the target of an IPI, and pass the effective CLOSID and RMID in a new struct. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-11-james.morse@arm.com
2025-03-12x86/resctrl: Generate default_ctrl instead of sharing itJames Morse1-2/+17
The struct rdt_resource default_ctrl is used by both the architecture code for resetting the hardware controls, and sometimes by the filesystem code as the default value for the schema, unless the bandwidth software controller is in use. Having the default exposed by the architecture code causes unnecessary duplication for each architecture as the default value must be specified, but can be derived from other schema properties. Now that the maximum bandwidth is explicitly described, resctrl can derive the default value from the schema format and the other resource properties. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-9-james.morse@arm.com
2025-03-12x86/resctrl: Add max_bw to struct resctrl_membwJames Morse1-0/+2
__rdt_get_mem_config_amd() and __get_mem_config_intel() both use the default_ctrl property as a maximum value. This is because the MBA schema works differently between these platforms. Doing this complicates determining whether the default_ctrl property belongs to the arch code, or can be derived from the schema format. Deriving the maximum or default value from the schema format would avoid the architecture code having to tell resctrl such obvious things as the maximum percentage is 100, and the maximum bitmap is all ones. Maximum bandwidth is always going to vary per platform. Add max_bw as a special case. This is currently used for the maximum MBA percentage on Intel platforms, but can be removed from the architecture code if 'percentage' becomes a schema format resctrl supports directly. This value isn't needed for other schema formats. This will allow the default_ctrl to be generated from the schema properties when it is needed. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-8-james.morse@arm.com
2025-03-12x86/resctrl: Remove data_width and the tabular formatJames Morse1-2/+0
The resctrl architecture code provides a data_width for the controls of each resource. This is used to zero pad all control values in the schemata file so they appear in columns. The same is done with the resource names to complete the visual effect. e.g. | SMBA:0=2048 | L3:0=00ff AMD platforms discover their maximum bandwidth for the MB resource from firmware, but hard-code the data_width to 4. If the maximum bandwidth requires more digits - the tabular format is silently broken. This is also broken when the mba_MBps mount option is used as the field width isn't updated. If new schema are added resctrl will need to be able to determine the maximum width. The benefit of this pretty-printing is questionable. Instead of handling runtime discovery of the data_width for AMD platforms, remove the feature. These fields are always zero padded so should be harmless to remove if the whole field has been treated as a number. In the above example, this would now look like this: | SMBA:0=2048 | L3:0=ff Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-7-james.morse@arm.com
2025-03-12x86/resctrl: Use schema type to determine the schema format stringJames Morse1-2/+2
Resctrl's architecture code gets to specify a format string that is used when printing schema entries. This is expected to be one of two values that the filesystem code supports. Setting this format string allows the architecture code to change the ABI resctrl presents to user-space. Instead, use the schema format enum to choose which format string to use. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-6-james.morse@arm.com
2025-03-12x86/resctrl: Use schema type to determine how to parse schema valuesJames Morse1-5/+12
Resctrl's architecture code gets to specify a function pointer that is used when parsing schema entries. This is expected to be one of two helpers from the filesystem code. Setting this function pointer allows the architecture code to change the ABI resctrl presents to user-space, and forces resctrl to expose these helpers. Instead, add a schema format enum to choose which schema parser to use. This allows the helpers to be made static and the structs used for passing arguments moved out of shared headers. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-5-james.morse@arm.com
2025-03-12x86/resctrl: Remove fflags from struct rdt_resourceJames Morse1-2/+0
The resctrl arch code specifies whether a resource controls a cache or memory using the fflags field. This field is then used by resctrl to determine which files should be exposed in the filesystem. Allowing the architecture to pick this value means the RFTYPE_ flags have to be in a shared header, and allows an architecture to create a combination that resctrl does not support. Remove the fflags field, and pick the value based on the resource id. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-4-james.morse@arm.com