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path: root/arch/x86/kernel/cpu/resctrl/internal.h
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2024-12-12x86/resctrl: Add write option to "mba_MBps_event" fileTony Luck
The "mba_MBps" mount option provides an alternate method to control memory bandwidth. Instead of specifying allowable bandwidth as a percentage of maximum possible, the user provides a MiB/s limit value. There is a file in each CTRL_MON group directory that shows the event currently in use. Allow writing that file to choose a different event. A user can choose any of the memory bandwidth monitoring events listed in /sys/fs/resctrl/info/L3_mon/mon_features independently for each CTRL_MON group by writing to each of the "mba_MBps_event" files. 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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20241206163148.83828-8-tony.luck@intel.com
2024-12-12x86/resctrl: Add "mba_MBps_event" file to CTRL_MON directoriesTony Luck
The "mba_MBps" mount option provides an alternate method to control memory bandwidth. Instead of specifying allowable bandwidth as a percentage of maximum possible, the user provides a MiB/s limit value. In preparation to allow the user to pick the memory bandwidth monitoring event used as input to the feedback loop, provide a file in each CTRL_MON group directory that shows the event currently in use. Note that this file is only visible when the "mba_MBps" mount option is in use. 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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20241206163148.83828-7-tony.luck@intel.com
2024-12-10x86/resctrl: Prepare for per-CTRL_MON group mba_MBps controlTony Luck
Resctrl uses local memory bandwidth event as input to the feedback loop when the mba_MBps mount option is used. This means that this mount option cannot be used on systems that only support monitoring of total bandwidth. Prepare to allow users to choose the input event independently for each CTRL_MON group by adding a global variable "mba_mbps_default_event" used to set the default event for each CTRL_MON group, and a new field "mba_mbps_event" in struct rdtgroup to track which event is used for each CTRL_MON group. Notes: 1) Both of these are only used when the user mounts the filesystem with the "mba_MBps" option. 2) Only check for support of local bandwidth event when initializing mba_mbps_default_event. Support for total bandwidth event can be added after other routines in resctrl have been updated to handle total bandwidth event. [ bp: Move mba_mbps_default_event extern into the arch header. ] 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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20241206163148.83828-3-tony.luck@intel.com
2024-12-09x86/resctrl: Introduce resctrl_file_fflags_init() to initialize fflagsBabu Moger
thread_throttle_mode_init() and mbm_config_rftype_init() both initialize fflags for resctrl files. Adding new files will involve adding another function to initialize the fflags. This can be simplified by adding a new function resctrl_file_fflags_init() and passing the file name and flags to be initialized. Consolidate fflags initialization into resctrl_file_fflags_init() and remove thread_throttle_mode_init() and mbm_config_rftype_init(). [ Tony: Drop __init attribute so resctrl_file_fflags_init() can be used at run time. ] Signed-off-by: Babu Moger <babu.moger@amd.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/r/20241206163148.83828-2-tony.luck@intel.com
2024-07-02x86/resctrl: Enable shared RMID mode on Sub-NUMA Cluster (SNC) systemsTony Luck
Hardware has two RMID configuration options for SNC systems. The default mode divides RMID counters between SNC nodes. E.g. with 200 RMIDs and two SNC nodes per L3 cache RMIDs 0..99 are used on node 0, and 100..199 on node 1. This isn't compatible with Linux resctrl usage. On this example system a process using RMID 5 would only update monitor counters while running on SNC node 0. The other mode is "RMID Sharing Mode". This is enabled by clearing bit 0 of the RMID_SNC_CONFIG (0xCA0) model specific register. In this mode the number of logical RMIDs is the number of physical RMIDs (from CPUID leaf 0xF) divided by the number of SNC nodes per L3 cache instance. A process can use the same RMID across different SNC nodes. See the "Intel Resource Director Technology Architecture Specification" for additional details. When SNC is enabled, update the MSR when a monitor domain is marked online. Technically this is overkill. It only needs to be done once per L3 cache instance rather than per SNC domain. But there is no harm in doing it more than once, and this is not in a critical path. 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/r/20240702173820.90368-3-tony.luck@intel.com
2024-07-02x86/resctrl: Fill out rmid_read structure for smp_call*() to read a counterTony Luck
mon_event_read() fills out most fields of the struct rmid_read that is passed via an smp_call*() function to a CPU that is part of the correct domain to read the monitor counters. With Sub-NUMA Cluster (SNC) mode there are now two cases to handle: 1) Reading a file that returns a value for a single domain. + Choose the CPU to execute from the domain cpu_mask 2) Reading a file that must sum across domains sharing an L3 cache instance. + Indicate to called code that a sum is needed by passing a NULL rdt_mon_domain pointer. + Choose the CPU from the L3 shared_cpu_map. 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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20240628215619.76401-16-tony.luck@intel.com
2024-07-02x86/resctrl: Allocate a new field in union mon_data_bitsTony Luck
When Sub-NUMA Cluster (SNC) mode is enabled, the legacy monitor reporting files must report the sum of the data from all of the SNC nodes that share the L3 cache that is referenced by the monitor file. Resctrl squeezes all the attributes of these files into 32 bits so they can be stored in the "priv" field of struct kernfs_node. Currently, only three monitor events are defined by enum resctrl_event_id so reducing it from 8 bits to 7 bits still provides more than enough space to represent all the known event types. But note that this choice was arbitrary. The "rid" field is also far wider than needed for the current number of resource id types. This structure is purely internal to resctrl, no ABI issues with modifying it. Subsequent changes may rearrange the allocation of bits between each of the fields as needed. Give the bit to a new "sum" field that indicates that reading this file must sum across SNC nodes. This bit also indicates that the domid field is the id of an L3 cache (instead of a domain id) to find which domains must be summed. Fix up other issues in the kerneldoc description for mon_data_bits. 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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20240628215619.76401-13-tony.luck@intel.com
2024-07-02x86/resctrl: Add a new field to struct rmid_read for summation of domainsTony Luck
When a user reads a monitor file rdtgroup_mondata_show() calls mon_event_read() to package up all the required details into an rmid_read structure which is passed across the smp_call*() infrastructure to code that will read data from hardware and return the value (or error status) in the rmid_read structure. Sub-NUMA Cluster (SNC) mode adds files with new semantics. These require the smp_call-ed code to sum event data from all domains that share an L3 cache. Add a pointer to the L3 "cacheinfo" structure to struct rmid_read for the data collection routines to use to pick the domains to be summed. [ Reinette: the rmid_read structure has become complex enough so document each of its fields and provide the kerneldoc documentation for struct rmid_read. ] Co-developed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20240628215619.76401-10-tony.luck@intel.com
2024-07-02x86/resctrl: Split the rdt_domain and rdt_hw_domain structuresTony Luck
The same rdt_domain structure is used for both control and monitor functions. But this results in wasted memory as some of the fields are only used by control functions, while most are only used for monitor functions. Split into separate rdt_ctrl_domain and rdt_mon_domain structures with just the fields required for control and monitoring respectively. Similar split of the rdt_hw_domain structure into rdt_hw_ctrl_domain and rdt_hw_mon_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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20240628215619.76401-5-tony.luck@intel.com
2024-07-02x86/resctrl: Prepare for different scope for control/monitor operationsTony Luck
Resctrl assumes that control and monitor operations on a resource are performed at the same scope. Prepare for systems that use different scope (specifically Intel needs to split the RDT_RESOURCE_L3 resource to use L3 scope for cache control and NODE scope for cache occupancy and memory bandwidth monitoring). Create separate domain lists for control and monitor operations. Note that errors during initialization of either control or monitor functions on a domain would previously result in that domain being excluded from both control and monitor operations. Now the domains are allocated independently it is no longer required to disable both control and monitor operations if either fail. 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> Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20240628215619.76401-4-tony.luck@intel.com
2024-04-24x86/resctrl: Simplify call convention for MSR update functionsTony Luck
The per-resource MSR update functions cat_wrmsr(), mba_wrmsr_intel(), and mba_wrmsr_amd() all take three arguments: (struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r) struct msr_param contains pointers to both struct rdt_resource and struct rdt_domain, thus only struct msr_param is necessary. Pass struct msr_param as a single parameter. Clean up formatting and fix some fir tree declaration ordering. No functional change. 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> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> Link: https://lore.kernel.org/r/20240308213846.77075-3-tony.luck@intel.com
2024-04-24x86/resctrl: Pass domain to target CPUTony Luck
reset_all_ctrls() and resctrl_arch_update_domains() use on_each_cpu_mask() to call rdt_ctrl_update() on potentially one CPU from each domain. But this means rdt_ctrl_update() needs to figure out which domain to apply changes to. Doing so requires a search of all domains in a resource, which can only be done safely if cpus_lock is held. Both callers do hold this lock, but there isn't a way for a function called on another CPU via IPI to verify this. Commit c0d848fcb09d ("x86/resctrl: Remove lockdep annotation that triggers false positive") removed the incorrect assertions. Add the target domain to the msr_param structure and call rdt_ctrl_update() for each domain separately using smp_call_function_single(). This means that rdt_ctrl_update() doesn't need to search for the domain and get_domain_from_cpu() can safely assert that the cpus_lock is held since the remaining callers do not use IPI. 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> Reviewed-by: James Morse <james.morse@arm.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> Link: https://lore.kernel.org/r/20240308213846.77075-2-tony.luck@intel.com
2024-04-03x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offlineReinette Chatre
Tony encountered this OOPS when the last CPU of a domain goes offline while running a kernel built with CONFIG_NO_HZ_FULL: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 Oops: 0000 [#1] PREEMPT SMP NOPTI ... RIP: 0010:__find_nth_andnot_bit+0x66/0x110 ... Call Trace: <TASK> ? __die() ? page_fault_oops() ? exc_page_fault() ? asm_exc_page_fault() cpumask_any_housekeeping() mbm_setup_overflow_handler() resctrl_offline_cpu() resctrl_arch_offline_cpu() cpuhp_invoke_callback() cpuhp_thread_fun() smpboot_thread_fn() kthread() ret_from_fork() ret_from_fork_asm() </TASK> The NULL pointer dereference is encountered while searching for another online CPU in the domain (of which there are none) that can be used to run the MBM overflow handler. Because the kernel is configured with CONFIG_NO_HZ_FULL the search for another CPU (in its effort to prefer those CPUs that aren't marked nohz_full) consults the mask representing the nohz_full CPUs, tick_nohz_full_mask. On a kernel with CONFIG_CPUMASK_OFFSTACK=y tick_nohz_full_mask is not allocated unless the kernel is booted with the "nohz_full=" parameter and because of that any access to tick_nohz_full_mask needs to be guarded with tick_nohz_full_enabled(). Replace the IS_ENABLED(CONFIG_NO_HZ_FULL) with tick_nohz_full_enabled(). The latter ensures tick_nohz_full_mask can be accessed safely and can be used whether kernel is built with CONFIG_NO_HZ_FULL enabled or not. [ Use Ingo's suggestion that combines the two NO_HZ checks into one. ] Fixes: a4846aaf3945 ("x86/resctrl: Add cpumask_any_housekeeping() for limbo/overflow") Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/ff8dfc8d3dcb04b236d523d1e0de13d2ef585223.1711993956.git.reinette.chatre@intel.com Closes: https://lore.kernel.org/lkml/ZgIFT5gZgIQ9A9G7@agluck-desk3/
2024-02-16x86/resctrl: Allow overflow/limbo handlers to be scheduled on any-but CPUJames Morse
When a CPU is taken offline resctrl may need to move the overflow or limbo handlers to run on a different CPU. Once the offline callbacks have been split, cqm_setup_limbo_handler() will be called while the CPU that is going offline is still present in the CPU mask. Pass the CPU to exclude to cqm_setup_limbo_handler() and mbm_setup_overflow_handler(). These functions can use a variant of cpumask_any_but() when selecting the CPU. -1 is used to indicate no CPUs need excluding. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-22-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Add helpers for system wide mon/alloc capableJames Morse
resctrl reads rdt_alloc_capable or rdt_mon_capable to determine whether any of the resources support the corresponding features. resctrl also uses the static keys that affect the architecture's context-switch code to determine the same thing. This forces another architecture to have the same static keys. As the static key is enabled based on the capable flag, and none of the filesystem uses of these are in the scheduler path, move the capable flags behind helpers, and use these in the filesystem code instead of the static key. After this change, only the architecture code manages and uses the static keys to ensure __resctrl_sched_in() does not need runtime checks. This avoids multiple architectures having to define the same static keys. Cases where the static key implicitly tested if the resctrl filesystem was mounted all have an explicit check now. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-20-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Move alloc/mon static keys into helpersJames Morse
resctrl enables three static keys depending on the features it has enabled. Another architecture's context switch code may look different, any static keys that control it should be buried behind helpers. Move the alloc/mon logic into arch-specific helpers as a preparatory step for making the rdt_enable_key's status something the arch code decides. This means other architectures don't have to mirror the static keys. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-18-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Make resctrl_mounted checks explicitJames Morse
The rdt_enable_key is switched when resctrl is mounted, and used to prevent a second mount of the filesystem. It also enables the architecture's context switch code. This requires another architecture to have the same set of static keys, as resctrl depends on them too. The existing users of these static keys are implicitly also checking if the filesystem is mounted. Make the resctrl_mounted checks explicit: resctrl can keep track of whether it has been mounted once. This doesn't need to be combined with whether the arch code is context switching the CLOSID. rdt_mon_enable_key is never used just to test that resctrl is mounted, but does also have this implication. Add a resctrl_mounted to all uses of rdt_mon_enable_key. This will allow the static key changing to be moved behind resctrl_arch_ calls. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-17-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Allow arch to allocate memory needed in resctrl_arch_rmid_read()James Morse
Depending on the number of monitors available, Arm's MPAM may need to allocate a monitor prior to reading the counter value. Allocating a contended resource may involve sleeping. __check_limbo() and mon_event_count() each make multiple calls to resctrl_arch_rmid_read(), to avoid extra work on contended systems, the allocation should be valid for multiple invocations of resctrl_arch_rmid_read(). The memory or hardware allocated is not specific to a domain. Add arch hooks for this allocation, which need calling before resctrl_arch_rmid_read(). The allocated monitor is passed to resctrl_arch_rmid_read(), then freed again afterwards. The helper can be called on any CPU, and can sleep. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-16-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Add cpumask_any_housekeeping() for limbo/overflowJames Morse
The limbo and overflow code picks a CPU to use from the domain's list of online CPUs. Work is then scheduled on these CPUs to maintain the limbo list and any counters that may overflow. cpumask_any() may pick a CPU that is marked nohz_full, which will either penalise the work that CPU was dedicated to, or delay the processing of limbo list or counters that may overflow. Perhaps indefinitely. Delaying the overflow handling will skew the bandwidth values calculated by mba_sc, which expects to be called once a second. Add cpumask_any_housekeeping() as a replacement for cpumask_any() that prefers housekeeping CPUs. This helper will still return a nohz_full CPU if that is the only option. The CPU to use is re-evaluated each time the limbo/overflow work runs. This ensures the work will move off a nohz_full CPU once a housekeeping CPU is available. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-13-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmidJames Morse
MPAM's PMG bits extend its PARTID space, meaning the same PMG value can be used for different control groups. This means once a CLOSID is allocated, all its monitoring ids may still be dirty, and held in limbo. Instead of allocating the first free CLOSID, on architectures where CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID is enabled, search closid_num_dirty_rmid[] to find the cleanest CLOSID. The CLOSID found is returned to closid_alloc() for the free list to be updated. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-11-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Allow RMID allocation to be scoped by CLOSIDJames Morse
MPAMs RMID values are not unique unless the CLOSID is considered as well. alloc_rmid() expects the RMID to be an independent number. Pass the CLOSID in to alloc_rmid(). Use this to compare indexes when allocating. If the CLOSID is not relevant to the index, this ends up comparing the free RMID with itself, and the first free entry will be used. With MPAM the CLOSID is included in the index, so this becomes a walk of the free RMID entries, until one that matches the supplied CLOSID is found. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-8-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Access per-rmid structures by indexJames Morse
x86 systems identify traffic using the CLOSID and RMID. The CLOSID is used to lookup the control policy, the RMID is used for monitoring. For x86 these are independent numbers. Arm's MPAM has equivalent features PARTID and PMG, where the PARTID is used to lookup the control policy. The PMG in contrast is a small number of bits that are used to subdivide PARTID when monitoring. The cache-occupancy monitors require the PARTID to be specified when monitoring. This means MPAM's PMG field is not unique. There are multiple PMG-0, one per allocated CLOSID/PARTID. If PMG is treated as equivalent to RMID, it cannot be allocated as an independent number. Bitmaps like rmid_busy_llc need to be sized by the number of unique entries for this resource. Treat the combined CLOSID and RMID as an index, and provide architecture helpers to pack and unpack an index. This makes the MPAM values unique. The domain's rmid_busy_llc and rmid_ptrs[] are then sized by index, as are domain mbm_local[] and mbm_total[]. x86 can ignore the CLOSID field when packing and unpacking an index, and report as many indexes as RMID. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-7-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Track the closid with the rmidJames Morse
x86's RMID are independent of the CLOSID. An RMID can be allocated, used and freed without considering the CLOSID. MPAM's equivalent feature is PMG, which is not an independent number, it extends the CLOSID/PARTID space. For MPAM, only PMG-bits worth of 'RMID' can be allocated for a single CLOSID. i.e. if there is 1 bit of PMG space, then each CLOSID can have two monitor groups. To allow resctrl to disambiguate RMID values for different CLOSID, everything in resctrl that keeps an RMID value needs to know the CLOSID too. This will always be ignored on x86. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Xin Hao <xhao@linux.alibaba.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-6-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Free rmid_ptrs from resctrl_exit()James Morse
rmid_ptrs[] is allocated from dom_data_init() but never free()d. While the exit text ends up in the linker script's DISCARD section, the direction of travel is for resctrl to be/have loadable modules. Add resctrl_put_mon_l3_config() to cleanup any memory allocated by rdt_get_mon_l3_config(). There is no reason to backport this to a stable kernel. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-3-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-01-24x86/resctrl: Implement new mba_MBps throttling heuristicTony Luck
The mba_MBps feedback loop increases throttling when a group is using more bandwidth than the target set by the user in the schemata file, and decreases throttling when below target. To avoid possibly stepping throttling up and down on every poll a flag "delta_comp" is set whenever throttling is changed to indicate that the actual change in bandwidth should be recorded on the next poll in "delta_bw". Throttling is only reduced if the current bandwidth plus delta_bw is below the user target. This algorithm works well if the workload has steady bandwidth needs. But it can go badly wrong if the workload moves to a different phase just as the throttling level changed. E.g. if the workload becomes essentially idle right as throttling level is increased, the value calculated for delta_bw will be more or less the old bandwidth level. If the workload then resumes, Linux may never reduce throttling because current bandwidth plus delta_bw is above the target set by the user. Implement a simpler heuristic by assuming that in the worst case the currently measured bandwidth is being controlled by the current level of throttling. Compute how much it may increase if throttling is relaxed to the next higher level. If that is still below the user target, then it is ok to reduce the amount of throttling. Fixes: ba0f26d8529c ("x86/intel_rdt/mba_sc: Prepare for feedback loop") Reported-by: Xiaochen Shen <xiaochen.shen@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> Tested-by: Xiaochen Shen <xiaochen.shen@intel.com> Link: https://lore.kernel.org/r/20240122180807.70518-1-tony.luck@intel.com
2024-01-23x86/resctrl: Read supported bandwidth sources from CPUIDBabu Moger
If the BMEC (Bandwidth Monitoring Event Configuration) feature is supported, the bandwidth events can be configured. The maximum supported bandwidth bitmask can be read from CPUID: CPUID_Fn80000020_ECX_x03 [Platform QoS Monitoring Bandwidth Event Configuration] Bits Description 31:7 Reserved 6:0 Identifies the bandwidth sources that can be tracked. While at it, move the mask checking to mon_config_write() before iterating over all the domains. Also, print the valid bitmask when the user tries to configure invalid event configuration value. The CPUID details are documented in the Processor Programming Reference (PPR) Vol 1.1 for AMD Family 19h Model 11h B1 - 55901 Rev 0.25 in the Link tag. Fixes: dc2a3e857981 ("x86/resctrl: Add interface to read mbm_total_bytes_config") 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://bugzilla.kernel.org/show_bug.cgi?id=206537 Link: https://lore.kernel.org/r/669896fa512c7451319fa5ca2fdb6f7e015b5635.1705359148.git.babu.moger@amd.com
2024-01-23x86/resctrl: Remove hard-coded memory bandwidth limitBabu Moger
The QOS Memory Bandwidth Enforcement Limit is reported by CPUID_Fn80000020_EAX_x01 and CPUID_Fn80000020_EAX_x02: Bits Description 31:0 BW_LEN: Size of the QOS Memory Bandwidth Enforcement Limit. Newer processors can support higher bandwidth limit than the current hard-coded value. Remove latter and detect using CPUID instead. Also, update the register variables eax and edx to match the AMD CPUID definition. The CPUID details are documented in the Processor Programming Reference (PPR) Vol 1.1 for AMD Family 19h Model 11h B1 - 55901 Rev 0.25 in the Link tag below. Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature") 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://bugzilla.kernel.org/show_bug.cgi?id=206537 Link: https://lore.kernel.org/r/c26a8ca79d399ed076cf8bf2e9fbc58048808289.1705359148.git.babu.moger@amd.com
2023-10-17x86/resctrl: Display RMID of resource groupBabu Moger
In x86, hardware uses RMID to identify a monitoring group. When a user creates a monitor group these details are not visible. These details can help resctrl debugging. Add RMID(mon_hw_id) to the monitor groups display in the resctrl interface. Users can see these details when resctrl is mounted with "-o debug" option. Add RFTYPE_MON_BASE that complements existing RFTYPE_CTRL_BASE and represents files belonging to monitoring groups. Other architectures do not use "RMID". Use the name mon_hw_id to refer to "RMID" in an effort to keep the naming generic. For example: $cat /sys/fs/resctrl/mon_groups/mon_grp1/mon_hw_id 3 Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Peter Newman <peternewman@google.com> Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Link: https://lore.kernel.org/r/20231017002308.134480-10-babu.moger@amd.com
2023-10-17x86/resctrl: Introduce "-o debug" mount optionBabu Moger
Add "-o debug" option to mount resctrl filesystem in debug mode. When in debug mode resctrl displays files that have the new RFTYPE_DEBUG flag to help resctrl debugging. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Peter Newman <peternewman@google.com> Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Link: https://lore.kernel.org/r/20231017002308.134480-7-babu.moger@amd.com
2023-10-17x86/resctrl: Rename rftype flags for consistencyBabu Moger
resctrl associates rftype flags with its files so that files can be chosen based on the resource, whether it is info or base, and if it is control or monitor type file. These flags use the RF_ as well as RFTYPE_ prefixes. Change the prefix to RFTYPE_ for all these flags to be consistent. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Peter Newman <peternewman@google.com> Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Link: https://lore.kernel.org/r/20231017002308.134480-4-babu.moger@amd.com
2023-10-17x86/resctrl: Simplify rftype flag definitionsBabu Moger
The rftype flags are bitmaps used for adding files under the resctrl filesystem. Some of these bitmap defines have one extra level of indirection which is not necessary. Drop the RF_* defines and simplify the macros. [ bp: Massage commit message. ] Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Peter Newman <peternewman@google.com> Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com> Link: https://lore.kernel.org/r/20231017002308.134480-3-babu.moger@amd.com
2023-10-11x86/resctrl: Enable non-contiguous CBMs in Intel CATMaciej Wieczor-Retman
The setting for non-contiguous 1s support in Intel CAT is hardcoded to false. On these systems, writing non-contiguous 1s into the schemata file will fail before resctrl passes the value to the hardware. In Intel CAT CPUID.0x10.1:ECX[3] and CPUID.0x10.2:ECX[3] stopped being reserved and now carry information about non-contiguous 1s value support for L3 and L2 cache respectively. The CAT capacity bitmask (CBM) supports a non-contiguous 1s value if the bit is set. The exception are Haswell systems where non-contiguous 1s value support needs to stay disabled since they can't make use of CPUID for Cache allocation. Originally-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Peter Newman <peternewman@google.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Peter Newman <peternewman@google.com> Link: https://lore.kernel.org/r/1849b487256fe4de40b30f88450cba3d9abc9171.1696934091.git.maciej.wieczor-retman@intel.com
2023-03-15x86/resctrl: Clear staged_config[] before and after it is usedShawn Wang
As a temporary storage, staged_config[] in rdt_domain should be cleared before and after it is used. The stale value in staged_config[] could cause an MSR access error. Here is a reproducer on a system with 16 usable CLOSIDs for a 15-way L3 Cache (MBA should be disabled if the number of CLOSIDs for MB is less than 16.) : mount -t resctrl resctrl -o cdp /sys/fs/resctrl mkdir /sys/fs/resctrl/p{1..7} umount /sys/fs/resctrl/ mount -t resctrl resctrl /sys/fs/resctrl mkdir /sys/fs/resctrl/p{1..8} An error occurs when creating resource group named p8: unchecked MSR access error: WRMSR to 0xca0 (tried to write 0x00000000000007ff) at rIP: 0xffffffff82249142 (cat_wrmsr+0x32/0x60) Call Trace: <IRQ> __flush_smp_call_function_queue+0x11d/0x170 __sysvec_call_function+0x24/0xd0 sysvec_call_function+0x89/0xc0 </IRQ> <TASK> asm_sysvec_call_function+0x16/0x20 When creating a new resource control group, hardware will be configured by the following process: rdtgroup_mkdir() rdtgroup_mkdir_ctrl_mon() rdtgroup_init_alloc() resctrl_arch_update_domains() resctrl_arch_update_domains() iterates and updates all resctrl_conf_type whose have_new_ctrl is true. Since staged_config[] holds the same values as when CDP was enabled, it will continue to update the CDP_CODE and CDP_DATA configurations. When group p8 is created, get_config_index() called in resctrl_arch_update_domains() will return 16 and 17 as the CLOSIDs for CDP_CODE and CDP_DATA, which will be translated to an invalid register - 0xca0 in this scenario. Fix it by clearing staged_config[] before and after it is used. [reinette: re-order commit tags] Fixes: 75408e43509e ("x86/resctrl: Allow different CODE/DATA configurations to be staged") Suggested-by: Xin Hao <xhao@linux.alibaba.com> Signed-off-by: Shawn Wang <shawnwang@linux.alibaba.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Reinette Chatre <reinette.chatre@intel.com> Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/2fad13f49fbe89687fc40e9a5a61f23a28d1507a.1673988935.git.reinette.chatre%40intel.com
2023-01-23x86/resctrl: Add interface to read mbm_total_bytes_configBabu Moger
The event configuration can be viewed by the user by reading the configuration file /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config. The event configuration settings are domain specific and will affect all the CPUs in the domain. Following are the types of events supported: ==== =========================================================== Bits Description ==== =========================================================== 6 Dirty Victims from the QOS domain to all types of memory 5 Reads to slow memory in the non-local NUMA domain 4 Reads to slow memory in the local NUMA domain 3 Non-temporal writes to non-local NUMA domain 2 Non-temporal writes to local NUMA domain 1 Reads to memory in the non-local NUMA domain 0 Reads to memory in the local NUMA domain ==== =========================================================== By default, the mbm_total_bytes_config is set to 0x7f to count all the event types. For example: $cat /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config 0=0x7f;1=0x7f;2=0x7f;3=0x7f In this case, the event mbm_total_bytes is configured with 0x7f on domains 0 to 3. 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/r/20230113152039.770054-10-babu.moger@amd.com
2023-01-23x86/resctrl: Support monitor configurationBabu Moger
Add a new field in struct mon_evt to support Bandwidth Monitoring Event Configuration (BMEC) and also update the "mon_features" display. The resctrl file "mon_features" will display the supported events and files that can be used to configure those events if monitor configuration is supported. Before the change: $ cat /sys/fs/resctrl/info/L3_MON/mon_features llc_occupancy mbm_total_bytes mbm_local_bytes After the change when BMEC is supported: $ cat /sys/fs/resctrl/info/L3_MON/mon_features llc_occupancy mbm_total_bytes mbm_total_bytes_config mbm_local_bytes mbm_local_bytes_config 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/r/20230113152039.770054-9-babu.moger@amd.com
2023-01-23x86/resctrl: Add __init attribute to rdt_get_mon_l3_config()Babu Moger
In an upcoming change, rdt_get_mon_l3_config() needs to call rdt_cpu_has() to query the monitor related features. It cannot be called right now because rdt_cpu_has() has the __init attribute but rdt_get_mon_l3_config() doesn't. Add the __init attribute to rdt_get_mon_l3_config() that is only called by get_rdt_mon_resources() that already has the __init attribute. Also make rdt_cpu_has() available to by rdt_get_mon_l3_config() via the internal header file. 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/r/20230113152039.770054-8-babu.moger@amd.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2023-01-23x86/resctrl: Add a new resource type RDT_RESOURCE_SMBABabu Moger
Add a new resource type RDT_RESOURCE_SMBA to handle the QoS enforcement policies on the external slow memory. Mostly initialization of the essentials. Setting fflags to RFTYPE_RES_MB configures the SMBA resource to have the same resctrl files as the existing MBA resource. The SMBA resource has identical properties to the existing MBA resource. These properties will be enumerated in an upcoming change and exposed via resctrl because of this flag. 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/r/20230113152039.770054-4-babu.moger@amd.com
2022-11-27x86/resctrl: Move MSR defines into msr-index.hBorislav Petkov
msr-index.h should contain all MSRs for easier grepping for MSR numbers when dealing with unchecked MSR access warnings, for example. Move the resctrl ones. Prefix IA32_PQR_ASSOC with "MSR_" while at it. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221106212923.20699-1-bp@alien8.de
2022-09-23x86/resctrl: Make resctrl_arch_rmid_read() return values in bytesJames Morse
resctrl_arch_rmid_read() returns a value in chunks, as read from the hardware. This needs scaling to bytes by mon_scale, as provided by the architecture code. Now that resctrl_arch_rmid_read() performs the overflow and corrections itself, it may as well return a value in bytes directly. This allows the accesses to the architecture specific 'hw' structure to be removed. Move the mon_scale conversion into resctrl_arch_rmid_read(). mbm_bw_count() is updated to calculate bandwidth from bytes. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-22-james.morse@arm.com
2022-09-23x86/resctrl: Rename and change the units of resctrl_cqm_thresholdJames Morse
resctrl_cqm_threshold is stored in a hardware specific chunk size, but exposed to user-space as bytes. This means the filesystem parts of resctrl need to know how the hardware counts, to convert the user provided byte value to chunks. The interface between the architecture's resctrl code and the filesystem ought to treat everything as bytes. Change the unit of resctrl_cqm_threshold to bytes. resctrl_arch_rmid_read() still returns its value in chunks, so this needs converting to bytes. As all the users have been touched, rename the variable to resctrl_rmid_realloc_threshold, which describes what the value is for. Neither r->num_rmid nor hw_res->mon_scale are guaranteed to be a power of 2, so the existing code introduces a rounding error from resctrl's theoretical fraction of the cache usage. This behaviour is kept as it ensures the user visible value matches the value read from hardware when the rmid will be reallocated. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-20-james.morse@arm.com
2022-09-23x86/resctrl: Move get_corrected_mbm_count() into resctrl_arch_rmid_read()James Morse
resctrl_arch_rmid_read() is intended as the function that an architecture agnostic resctrl filesystem driver can use to read a value in bytes from a counter. Currently the function returns the MBM values in chunks directly from hardware. When reading a bandwidth counter, get_corrected_mbm_count() must be used to correct the value read. get_corrected_mbm_count() is architecture specific, this work should be done in resctrl_arch_rmid_read(). Move the function calls. This allows the resctrl filesystems's chunks value to be removed in favour of the architecture private version. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-19-james.morse@arm.com
2022-09-23x86/resctrl: Move mbm_overflow_count() into resctrl_arch_rmid_read()James Morse
resctrl_arch_rmid_read() is intended as the function that an architecture agnostic resctrl filesystem driver can use to read a value in bytes from a counter. Currently the function returns the MBM values in chunks directly from hardware. When reading a bandwidth counter, mbm_overflow_count() must be used to correct for any possible overflow. mbm_overflow_count() is architecture specific, its behaviour should be part of resctrl_arch_rmid_read(). Move the mbm_overflow_count() calls into resctrl_arch_rmid_read(). This allows the resctrl filesystems's prev_msr to be removed in favour of the architecture private version. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-18-james.morse@arm.com
2022-09-23x86/resctrl: Abstract __rmid_read()James Morse
__rmid_read() selects the specified eventid and returns the counter value from the MSR. The error handling is architecture specific, and handled by the callers, rdtgroup_mondata_show() and __mon_event_count(). Error handling should be handled by architecture specific code, as a different architecture may have different requirements. MPAM's counters can report that they are 'not ready', requiring a second read after a short delay. This should be hidden from resctrl. Make __rmid_read() the architecture specific function for reading a counter. Rename it resctrl_arch_rmid_read() and move the error handling into it. A read from a counter that hardware supports but resctrl does not now returns -EINVAL instead of -EIO from the default case in __mon_event_count(). It isn't possible for user-space to see this change as resctrl doesn't expose counters it doesn't support. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-16-james.morse@arm.com
2022-09-23x86/resctrl: Allow per-rmid arch private storage to be resetJames Morse
To abstract the rmid counters into a helper that returns the number of bytes counted, architecture specific per-rmid state is needed. It needs to be possible to reset this hidden state, as the values may outlive the life of an rmid, or the mount time of the filesystem. mon_event_read() is called with first = true when an rmid is first allocated in mkdir_mondata_subdir(). Add resctrl_arch_reset_rmid() and call it from __mon_event_count()'s rr->first check. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-15-james.morse@arm.com
2022-09-22x86/resctrl: Add per-rmid arch private storage for overflow and chunksJames Morse
A renamed __rmid_read() is intended as the function that an architecture agnostic resctrl filesystem driver can use to read a value in bytes from a counter. Currently the function returns the MBM values in chunks directly from hardware. For bandwidth counters the resctrl filesystem uses this to calculate the number of bytes ever seen. MPAM's scaling of counters can be changed at runtime, reducing the resolution but increasing the range. When this is changed the prev_msr values need to be converted by the architecture code. Add an array for per-rmid private storage. The prev_msr and chunks values will move here to allow resctrl_arch_rmid_read() to always return the number of bytes read by this counter without assistance from the filesystem. The values are moved in later patches when the overflow and correction calls are moved into __rmid_read(). Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-14-james.morse@arm.com
2022-09-22x86/resctrl: Calculate bandwidth from the previous __mon_event_count() chunksJames Morse
mbm_bw_count() is only called by the mbm_handle_overflow() worker once a second. It reads the hardware register, calculates the bandwidth and updates m->prev_bw_msr which is used to hold the previous hardware register value. Operating directly on hardware register values makes it difficult to make this code architecture independent, so that it can be moved to /fs/, making the mba_sc feature something resctrl supports with no additional support from the architecture. Prior to calling mbm_bw_count(), mbm_update() reads from the same hardware register using __mon_event_count(). Change mbm_bw_count() to use the current chunks value most recently saved by __mon_event_count(). This removes an extra call to __rmid_read(). Instead of using m->prev_msr to calculate the number of chunks seen, use the rr->val that was updated by __mon_event_count(). This removes an extra call to mbm_overflow_count() and get_corrected_mbm_count(). Calculating bandwidth like this means mbm_bw_count() no longer operates on hardware register values directly. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-13-james.morse@arm.com
2022-09-22x86/resctrl: Allow update_mba_bw() to update controls directlyJames Morse
update_mba_bw() calculates a new control value for the MBA resource based on the user provided mbps_val and the current measured bandwidth. Some control values need remapping by delay_bw_map(). It does this by calling wrmsrl() directly. This needs splitting up to be done by an architecture specific helper, so that the remainder can eventually be moved to /fs/. Add resctrl_arch_update_one() to apply one configuration value to the provided resource and domain. This avoids the staging and cross-calling that is only needed with changes made by user-space. delay_bw_map() moves to be part of the arch code, to maintain the 'percentage control' view of MBA resources in resctrl. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-12-james.morse@arm.com
2022-09-22x86/resctrl: Remove architecture copy of mbps_valJames Morse
The resctrl arch code provides a second configuration array mbps_val[] for the MBA software controller. Since resctrl switched over to allocating and freeing its own array when needed, nothing uses the arch code version. Remove it. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-11-james.morse@arm.com
2022-09-22x86/resctrl: Create mba_sc configuration in the rdt_domainJames Morse
To support resctrl's MBA software controller, the architecture must provide a second configuration array to hold the mbps_val[] from user-space. This complicates the interface between the architecture specific code and the filesystem portions of resctrl that will move to /fs/, to allow multiple architectures to support resctrl. Make the filesystem parts of resctrl create an array for the mba_sc values. The software controller can be changed to use this, allowing the architecture code to only consider the values configured in hardware. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-9-james.morse@arm.com
2022-09-22x86/resctrl: Add domain offline callback for resctrl workJames Morse
Because domains are exposed to user-space via resctrl, the filesystem must update its state when CPU hotplug callbacks are triggered. Some of this work is common to any architecture that would support resctrl, but the work is tied up with the architecture code to free the memory. Move the monitor subdir removal and the cancelling of the mbm/limbo works into a new resctrl_offline_domain() call. These bits are not specific to the architecture. Grouping them in one function allows that code to be moved to /fs/ and re-used by another architecture. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jamie Iles <quic_jiles@quicinc.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20220902154829.30399-6-james.morse@arm.com