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2026-02-10Merge tag 'x86_cache_for_v7.0_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: - Extend the resctrl machinery to support telemetry monitoring on Intel (Tony Luck) The practical usage of this is being able to tell how much energy or how much work can be attributed to a group of tasks tracked under a single idenitifier. Prepend this work with proper refactoring of resctrl domains handling code. * tag 'x86_cache_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits) x86,fs/resctrl: Update documentation for telemetry events x86/resctrl: Enable RDT_RESOURCE_PERF_PKG fs/resctrl: Move RMID initialization to first mount x86,fs/resctrl: Compute number of RMIDs as minimum across resources fs/resctrl: Move allocation/free of closid_num_dirty_rmid[] x86/resctrl: Handle number of RMIDs supported by RDT_RESOURCE_PERF_PKG x86/resctrl: Add energy/perf choices to rdt boot option x86,fs/resctrl: Handle domain creation/deletion for RDT_RESOURCE_PERF_PKG fs/resctrl: Refactor rmdir_mondata_subdir_allrdtgrp() fs/resctrl: Refactor mkdir_mondata_subdir() x86/resctrl: Read telemetry events x86/resctrl: Find and enable usable telemetry events x86,fs/resctrl: Add architectural event pointer x86,fs/resctrl: Fill in details of events for performance and energy GUIDs x86/resctrl: Discover hardware telemetry events fs/resctrl: Emphasize that L3 monitoring resource is required for summing domains x86,fs/resctrl: Add and initialize a resource for package scope monitoring x86,fs/resctrl: Add an architectural hook called for first mount x86,fs/resctrl: Support binary fixed point event counters x86,fs/resctrl: Handle events that can be read from any CPU ...
2026-01-13x86/resctrl: Fix memory bandwidth counter width for HygonXiaochen Shen
The memory bandwidth calculation relies on reading the hardware counter and measuring the delta between samples. To ensure accurate measurement, the software reads the counter frequently enough to prevent it from rolling over twice between reads. The default Memory Bandwidth Monitoring (MBM) counter width is 24 bits. Hygon CPUs provide a 32-bit width counter, but they do not support the MBM capability CPUID leaf (0xF.[ECX=1]:EAX) to report the width offset (from 24 bits). Consequently, the kernel falls back to the 24-bit default counter width, which causes incorrect overflow handling on Hygon CPUs. Fix this by explicitly setting the counter width offset to 8 bits (resulting in a 32-bit total counter width) for Hygon CPUs. Fixes: d8df126349da ("x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper") Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net> 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> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251209062650.1536952-3-shenxiaochen@open-hieco.net
2026-01-13x86/resctrl: Add missing resctrl initialization for HygonXiaochen Shen
Hygon CPUs supporting Platform QoS features currently undergo partial resctrl initialization through resctrl_cpu_detect() in the Hygon BSP init helper and AMD/Hygon common initialization code. However, several critical data structures remain uninitialized for Hygon CPUs in the following paths: - get_mem_config()-> __rdt_get_mem_config_amd(): rdt_resource::membw,alloc_capable hw_res::num_closid - rdt_init_res_defs()->rdt_init_res_defs_amd(): rdt_resource::cache hw_res::msr_base,msr_update Add the missing AMD/Hygon common initialization to ensure proper Platform QoS functionality on Hygon CPUs. Fixes: d8df126349da ("x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper") Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251209062650.1536952-2-shenxiaochen@open-hieco.net
2026-01-10x86/resctrl: Enable RDT_RESOURCE_PERF_PKGTony Luck
Since telemetry events are enumerated on resctrl mount the RDT_RESOURCE_PERF_PKG resource is not considered "monitoring capable" during early resctrl initialization. This means that the domain list for RDT_RESOURCE_PERF_PKG is not built when the CPU hotplug notifiers are registered and run for the first time right after resctrl initialization. Mark the RDT_RESOURCE_PERF_PKG as "monitoring capable" upon successful telemetry event enumeration to ensure future CPU hotplug events include this resource and initialize its domain list for CPUs that are already online. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-10x86,fs/resctrl: Compute number of RMIDs as minimum across resourcesTony Luck
resctrl assumes that only the L3 resource supports monitor events, so it simply takes the rdt_resource::num_rmid from RDT_RESOURCE_L3 as the system's number of RMIDs. The addition of telemetry events in a different resource breaks that assumption. Compute the number of available RMIDs as the minimum value across all mon_capable resources (analogous to how the number of CLOSIDs is computed across alloc_capable resources). Note that mount time enumeration of the telemetry resource means that this number can be reduced. If this happens, then some memory will be wasted as the allocations for rdt_l3_mon_domain::mbm_states[] and rdt_l3_mon_domain::rmid_busy_llc created during resctrl initialization will be larger than needed. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-09x86/resctrl: Add energy/perf choices to rdt boot optionTony Luck
Legacy resctrl features are enumerated by X86_FEATURE_* flags. These may be overridden by quirks to disable features in the case of errata. Users can use kernel command line options to either disable a feature, or to force enable a feature that was disabled by a quirk. A different approach is needed for hardware features that do not have an X86_FEATURE_* flag. Update parsing of the "rdt=" boot parameter to call the telemetry driver directly to handle new "perf" and "energy" options that controls activation of telemetry monitoring of the named type. By itself a "perf" or "energy" option controls the forced enabling or disabling (with ! prefix) of all event groups of the named type. A ":guid" suffix allows for fine grained control per event group. [ bp: s/intel_aet_option/intel_handle_aet_option/g ] Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-09x86,fs/resctrl: Handle domain creation/deletion for RDT_RESOURCE_PERF_PKGTony Luck
The L3 resource has several requirements for domains. There are per-domain structures that hold the 64-bit values of counters, and elements to keep track of the overflow and limbo threads. None of these are needed for the PERF_PKG resource. The hardware counters are wide enough that they do not wrap around for decades. Define a new rdt_perf_pkg_mon_domain structure which just consists of the standard rdt_domain_hdr to keep track of domain id and CPU mask. Update resctrl_online_mon_domain() for RDT_RESOURCE_PERF_PKG. The only action needed for this resource is to create and populate domain directories if a domain is added while resctrl is mounted. Similarly resctrl_offline_mon_domain() only needs to remove domain directories. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-09x86,fs/resctrl: Add architectural event pointerTony Luck
The resctrl file system layer passes the domain, RMID, and event id to the architecture to fetch an event counter. Fetching a telemetry event counter requires additional information that is private to the architecture, for example, the offset into MMIO space from where the counter should be read. Add mon_evt::arch_priv that architecture can use for any private data related to the event. The resctrl filesystem initializes mon_evt::arch_priv when the architecture enables the event and passes it back to architecture when needing to fetch an event counter. Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-09x86/resctrl: Discover hardware telemetry eventsTony Luck
Each CPU collects data for telemetry events that it sends to the nearest telemetry event aggregator either when the value of MSR_IA32_PQR_ASSOC.RMID changes, or when a two millisecond timer expires. There is a feature type ("energy" or "perf"), GUID, and MMIO region associated with each aggregator. This combination links to an XML description of the set of telemetry events tracked by the aggregator. XML files are published by Intel in a GitHub repository¹. The telemetry event aggregators maintain per-RMID per-event counts of the total seen for all the CPUs. There may be multiple telemetry event aggregators per package. There are separate sets of aggregators for each feature type. Aggregators in a set may have different GUIDs. All aggregators with the same feature type and GUID are symmetric keeping counts for the same set of events for the CPUs that provide data to them. The XML file for each aggregator provides the following information: 0) Feature type of the events ("perf" or "energy") 1) Which telemetry events are tracked by the aggregator. 2) The order in which the event counters appear for each RMID. 3) The value type of each event counter (integer or fixed-point). 4) The number of RMIDs supported. 5) Which additional aggregator status registers are included. 6) The total size of the MMIO region for an aggregator. Introduce struct event_group that condenses the relevant information from an XML file. Hereafter an "event group" refers to a group of events of a particular feature type (event_group::pfname set to "energy" or "perf") with a particular GUID. Use event_group::pfname to determine the feature id needed to obtain the aggregator details. It will later be used in console messages and with the rdt= boot parameter. The INTEL_PMT_TELEMETRY driver enumerates support for telemetry events. This driver provides intel_pmt_get_regions_by_feature() to list all available telemetry event aggregators of a given feature type. The list includes the "guid", the base address in MMIO space for the region where the event counters are exposed, and the package id where the all the CPUs that report to this aggregator are located. Call INTEL_PMT_TELEMETRY's intel_pmt_get_regions_by_feature() for each event group to obtain a private copy of that event group's aggregator data. Duplicate the aggregator data between event groups that have the same feature type but different GUID. Further processing on this private copy will be unique to the event group. ¹https://github.com/intel/Intel-PMT [ bp: Zap text explaining the code, s/guid/GUID/g ] Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-09x86,fs/resctrl: Add and initialize a resource for package scope monitoringTony Luck
Add a new PERF_PKG resource and introduce package level scope for monitoring telemetry events so that CPU hotplug notifiers can build domains at the package granularity. Use the physical package ID available via topology_physical_package_id() to identify the monitoring domains with package level scope. This enables user space to use: /sys/devices/system/cpu/cpuX/topology/physical_package_id to identify the monitoring domain a CPU is associated with. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-09x86,fs/resctrl: Add an architectural hook called for first mountTony Luck
Enumeration of Intel telemetry events is an asynchronous process involving several mutually dependent drivers added as auxiliary devices during the device_initcall() phase of Linux boot. The process finishes after the probe functions of these drivers completes. But this happens after resctrl_arch_late_init() is executed. Tracing the enumeration process shows that it does complete a full seven seconds before the earliest possible mount of the resctrl file system (when included in /etc/fstab for automatic mount by systemd). Add a hook for use by telemetry event enumeration and initialization and run it once at the beginning of resctrl mount without any locks held. The architecture is responsible for any required locking. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20260105191711.GBaVwON5nZn-uO6Sqg@fat_crate.local
2026-01-05x86,fs/resctrl: Support binary fixed point event countersTony Luck
resctrl assumes that all monitor events can be displayed as unsigned decimal integers. Hardware architecture counters may provide some telemetry events with greater precision where the event is not a simple count, but is a measurement of some sort (e.g. Joules for energy consumed). Add a new argument to resctrl_enable_mon_event() for architecture code to inform the file system that the value for a counter is a fixed-point value with a specific number of binary places. Only allow architecture to use floating point format on events that the file system has marked with mon_evt::is_floating_point which reflects the contract with user space on how the event values are displayed. Display fixed point values with values rounded to ceil(binary_bits * log10(2)) decimal places. Special case for zero binary bits to print "{value}.0". Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-05x86,fs/resctrl: Handle events that can be read from any CPUTony Luck
resctrl assumes that monitor events can only be read from a CPU in the cpumask_t set of each domain. This is true for x86 events accessed with an MSR interface, but may not be true for other access methods such as MMIO. Introduce and use flag mon_evt::any_cpu, settable by architecture, that indicates there are no restrictions on which CPU can read that event. This flag is not supported by the L3 event reading that requires to be run on a CPU that belongs to the L3 domain of the event being read. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-05x86,fs/resctrl: Rename some L3 specific functionsTony Luck
With the arrival of monitor events tied to new domains associated with a different resource it would be clearer if the L3 resource specific functions are more accurately named. Rename three groups of functions: Functions that allocate/free architecture per-RMID MBM state information: arch_domain_mbm_alloc() -> l3_mon_domain_mbm_alloc() mon_domain_free() -> l3_mon_domain_free() Functions that allocate/free filesystem per-RMID MBM state information: domain_setup_mon_state() -> domain_setup_l3_mon_state() domain_destroy_mon_state() -> domain_destroy_l3_mon_state() Initialization/exit: rdt_get_mon_l3_config() -> rdt_get_l3_mon_config() resctrl_mon_resource_init() -> resctrl_l3_mon_resource_init() resctrl_mon_resource_exit() -> resctrl_l3_mon_resource_exit() Ensure kernel-doc descriptions of these functions' return values are present and correctly formatted. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-05x86,fs/resctrl: Rename struct rdt_mon_domain and rdt_hw_mon_domainTony Luck
The upcoming telemetry event monitoring is not tied to the L3 resource and will have a new domain structure. Rename the L3 resource specific domain data structures to include "l3_" in their names to avoid confusion between the different resource specific domain structures: rdt_mon_domain -> rdt_l3_mon_domain rdt_hw_mon_domain -> rdt_hw_l3_mon_domain No functional change. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-04x86,fs/resctrl: Refactor domain create/remove using struct rdt_domain_hdrTony Luck
Up until now, all monitoring events were associated with the L3 resource and it made sense to use the L3 specific "struct rdt_mon_domain *" argument to functions operating on domains. Telemetry events will be tied to a new resource with its instances represented by a new domain structure that, just like struct rdt_mon_domain, starts with the generic struct rdt_domain_hdr. Prepare to support domains belonging to different resources by changing the calling convention of functions operating on domains. Pass the generic header and use that to find the domain specific structure where needed. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-04x86/resctrl: Clean up domain_remove_cpu_ctrl()Tony Luck
For symmetry with domain_remove_cpu_mon() refactor domain_remove_cpu_ctrl() to take an early return when removing a CPU does not empty the domain. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-04x86/resctrl: Refactor domain_remove_cpu_mon() ready for new domain typesTony Luck
New telemetry events will be associated with a new package scoped resource with a new domain structure. Refactor domain_remove_cpu_mon() so all the L3 domain processing is separate from the general domain action of clearing the CPU bit in the mask. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-04x86/resctrl: Move L3 initialization into new helper functionTony Luck
Carve out the resource monitoring domain init code into a separate helper in order to be able to initialize new types of monitoring domains besides the usual L3 ones. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-04x86,fs/resctrl: Improve domain type checkingTony Luck
Every resctrl resource has a list of domain structures. struct rdt_ctrl_domain and struct rdt_mon_domain both begin with struct rdt_domain_hdr with rdt_domain_hdr::type used in validity checks before accessing the domain of a particular type. Add the resource id to struct rdt_domain_hdr in preparation for a new monitoring domain structure that will be associated with a new monitoring resource. Improve existing domain validity checks with a new helper domain_header_is_valid() that checks both domain type and resource id. domain_header_is_valid() should be used before every call to container_of() that accesses a domain structure. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2025-11-21x86,fs/resctrl: Detect io_alloc featureBabu Moger
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
2025-11-21x86/resctrl: Add SDCIAE feature in the command line optionsBabu Moger
Add a kernel command-line parameter to enable or disable the exposure of the L3 Smart Data Cache Injection Allocation Enforcement (SDCIAE) hardware feature to resctrl. 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/c623edf7cb369ba9da966de47d9f1b666778a40e.1762995456.git.babu.moger@amd.com
2025-09-15x86/resctrl: Configure mbm_event mode if supportedBabu Moger
Configure mbm_event mode on AMD platforms. On AMD platforms, it is recommended to use the mbm_event mode, if supported, to prevent the hardware from resetting counters between reads. This can result in misleading values or display "Unavailable" if no counter is assigned to the event. Enable mbm_event mode, known as ABMC (Assignable Bandwidth Monitoring Counters) on AMD, by default if the system supports it. Update ABMC across all logical processors within the resctrl domain to ensure proper functionality. 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: Detect Assignable Bandwidth Monitoring feature detailsBabu Moger
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 Moger
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/resctrl: Add ABMC feature in the command line optionsBabu Moger
Add a kernel command-line parameter to enable or disable the exposure of the ABMC (Assignable Bandwidth Monitoring Counters) hardware feature to resctrl. 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 Luck
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/resctrl: Remove the rdt_mon_features global variableTony Luck
rdt_mon_features is used as a bitmask of enabled monitor events. A monitor event's status is now maintained in mon_evt::enabled with all monitor events' mon_evt structures found in the filesystem's mon_event_all[] array. Remove the remaining uses of rdt_mon_features. 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 Luck
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 Luck
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 Tan
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
2025-05-27Merge tag 'x86_cache_for_v6.16_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: "Carve out the resctrl filesystem-related code into fs/resctrl/ so that multiple architectures can share the fs API for manipulating their respective hw resource control implementation. This is the second step in the work towards sharing the resctrl filesystem interface, the next one being plugging ARM's MPAM into the aforementioned fs API" * tag 'x86_cache_for_v6.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits) MAINTAINERS: Add reviewers for fs/resctrl x86,fs/resctrl: Move the resctrl filesystem code to live in /fs/resctrl x86/resctrl: Always initialise rid field in rdt_resources_all[] x86/resctrl: Relax some asm #includes x86/resctrl: Prefer alloc(sizeof(*foo)) idiom in rdt_init_fs_context() x86/resctrl: Squelch whitespace anomalies in resctrl core code x86/resctrl: Move pseudo lock prototypes to include/linux/resctrl.h x86/resctrl: Fix types in resctrl_arch_mon_ctx_{alloc,free}() stubs x86/resctrl: Move enum resctrl_event_id to resctrl.h x86/resctrl: Move the filesystem bits to headers visible to fs/resctrl fs/resctrl: Add boiler plate for external resctrl code x86/resctrl: Add 'resctrl' to the title of the resctrl documentation x86/resctrl: Split trace.h x86/resctrl: Expand the width of domid by replacing mon_data_bits x86/resctrl: Add end-marker to the resctrl_event_id enum x86/resctrl: Move is_mba_sc() out of core.c x86/resctrl: Drop __init/__exit on assorted symbols x86/resctrl: Resctrl_exit() teardown resctrl but leave the mount point x86/resctrl: Check all domains are offline in resctrl_exit() x86/resctrl: Rename resctrl_sched_in() to begin with "resctrl_arch_" ...
2025-05-16x86/resctrl: Always initialise rid field in rdt_resources_all[]James Morse
x86 has an array, rdt_resources_all[], of all possible resources. The for-each-resource walkers depend on the rid field of all resources being initialised. If the array ever grows due to another architecture adding a resource type that is not defined on x86, the for-each-resources walkers will loop forever. Initialise all the rid values in resctrl_arch_late_init() before any for-each-resource walker can be called. 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/20250515165855.31452-24-james.morse@arm.com
2025-05-16x86/resctrl: Move is_mba_sc() out of core.cJames Morse
is_mba_sc() is defined in core.c, but has no callers there. It does not access any architecture private structures. Move this to rdtgroup.c where the majority of callers are. This makes the move of the filesystem code to /fs/ cleaner. 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/20250515165855.31452-11-james.morse@arm.com
2025-05-15x86/resctrl: Drop __init/__exit on assorted symbolsJames Morse
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
2025-05-02x86/msr: Add explicit includes of <asm/msr.h>Xin Li (Intel)
For historic reasons there are some TSC-related functions in the <asm/msr.h> header, even though there's an <asm/tsc.h> header. To facilitate the relocation of rdtsc{,_ordered}() from <asm/msr.h> to <asm/tsc.h> and to eventually eliminate the inclusion of <asm/msr.h> in <asm/tsc.h>, add an explicit <asm/msr.h> dependency to the source files that reference definitions from <asm/msr.h>. [ mingo: Clarified the changelog. ] Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Uros Bizjak <ubizjak@gmail.com> Link: https://lore.kernel.org/r/20250501054241.1245648-1-xin@zytor.com
2025-04-10x86/msr: Rename 'wrmsrl_safe()' to 'wrmsrq_safe()'Ingo Molnar
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org>
2025-04-10x86/msr: Rename 'wrmsrl()' to 'wrmsrq()'Ingo Molnar
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org>
2025-04-10x86/msr: Rename 'rdmsrl()' to 'rdmsrq()'Ingo Molnar
Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Xin Li <xin@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org>
2025-03-12x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their callersJames Morse
Each of get_{mon,ctrl}_domain_from_cpu() only has one caller. Once the filesystem code is moved to /fs/, there is no equivalent to core.c. Move these functions to each live next to their caller. This allows them to be made static and the header file entries to be removed. 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/20250311183715.16445-31-james.morse@arm.com
2025-03-12x86/resctrl: Move RFTYPE flags to be managed by resctrlJames Morse
resctrl_file_fflags_init() is called from the architecture specific code to make the 'thread_throttle_mode' file visible. The architecture specific code has already set the membw.throttle_mode in the rdt_resource. This forces the RFTYPE flags used by resctrl to be exposed to the architecture specific code. This doesn't need to be specific to the architecture, the throttle_mode can be used by resctrl to determine if the 'thread_throttle_mode' file should be visible. This allows the RFTYPE flags to be private to resctrl. Add thread_throttle_mode_init(), and use it to call resctrl_file_fflags_init() from resctrl_init(). This avoids publishing an extra function between the architecture and filesystem code. 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> 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/20250311183715.16445-28-james.morse@arm.com
2025-03-12x86/resctrl: Move mba_mbps_default_event init to filesystem codeJames Morse
mba_mbps_default_event is initialised based on whether mbm_local or mbm_total is supported. In the case of both, it is initialised to mbm_local. mba_mbps_default_event is initialised in core.c's get_rdt_mon_resources(), while all the readers are in rdtgroup.c. After this code is split into architecture-specific and filesystem code, get_rdt_mon_resources() remains part of the architecture code, which would mean mba_mbps_default_event has to be exposed by the filesystem code. Move the initialisation to the filesystem's resctrl_mon_resource_init(). 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> 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/20250311183715.16445-22-james.morse@arm.com
2025-03-12x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMECJames Morse
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: Move the is_mbm_*_enabled() helpers to asm/resctrl.hJames Morse
The architecture specific parts of resctrl provide helpers like is_mbm_total_enabled() and is_mbm_local_enabled() to hide accesses to the rdt_mon_features bitmap. Exposing a group of helpers between the architecture and filesystem code is preferable to a single unsigned-long like rdt_mon_features. Helpers can be more readable and have a well defined behaviour, while allowing architectures to hide more complex behaviour. Once the filesystem parts of resctrl are moved, these existing helpers can no longer live in internal.h. Move them to include/linux/resctrl.h Once these are exposed to the wider kernel, they should have a 'resctrl_arch_' prefix, to fit the rest of the arch<->fs interface. Move and rename the helpers that touch rdt_mon_features directly. is_mbm_event() and is_mbm_enabled() are only called from rdtgroup.c, so can be moved into that file. 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: 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: 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/20250311183715.16445-19-james.morse@arm.com
2025-03-12x86/resctrl: Move monitor exit work to a resctrl exit callJames Morse
rdt_put_mon_l3_config() is called via the architecture's resctrl_arch_exit() call, and appears to free the rmid_ptrs[] and closid_num_dirty_rmid[] arrays. In reality this code is marked __exit, and is removed by the linker as resctrl can't be built as a module. To separate the filesystem and architecture parts of resctrl, this free()ing work needs to be triggered by the filesystem, as these structures belong to the filesystem code. Rename rdt_put_mon_l3_config() to resctrl_mon_resource_exit() and call it from resctrl_exit(). The kfree() is currently dependent on r->mon_capable. 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/20250311183715.16445-16-james.morse@arm.com
2025-03-12x86/resctrl: Move rdt_find_domain() to be visible to arch and fs codeJames Morse
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 Morse
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: Generate default_ctrl instead of sharing itJames Morse
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 Morse
__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 Morse
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