user/sven/linux.git/include/linux/resctrl.h, branch v6.16.1

x86,fs/resctrl: Remove inappropriate references to cacheinfo in the resctrl subsystem

2025-06-16T19:06:12Z

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 Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Tested-by: Tony Luck Link: https://lore.kernel.org/20250530182053.37502-2-qinyuntan@linux.alibaba.com

x86/resctrl: Move pseudo lock prototypes to include/linux/resctrl.h

2025-05-16T10:21:00Z

The resctrl pseudo-lock feature allows an architecture to allocate data into particular cache portions, which are then treated as reserved to avoid that data ever being evicted. Setting this up is deeply architecture specific as it involves disabling prefetchers etc. It is not possible to support this kind of feature on arm64. Risc-V is assumed to be the same. The prototypes for the architecture code were added to x86's asm/resctrl.h, with other architectures able to provide stubs for their architecture. This forces other architectures to provide identical stubs. Move the prototypes and stubs to linux/resctrl.h, and switch between them using the existing Kconfig symbol. Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Tested-by: Fenghua Yu Tested-by: Babu Moger Tested-by: Shaopeng Tan Tested-by: Tony Luck Link: https://lore.kernel.org/20250515165855.31452-20-james.morse@arm.com

x86/resctrl: Move enum resctrl_event_id to resctrl.h

2025-05-16T10:10:20Z

resctrl_types.h contains common types and constants to enable architectures to use these types in their definitions within asm/resctrl.h. enum resctrl_event_id was placed in resctrl_types.h for resctrl_arch_get_cdp_enabled() and resctrl_arch_set_cdp_enabled(), but these two functions are no longer inlined by any architecture. Move enum resctrl_event_id to resctrl.h. Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Tested-by: Fenghua Yu Tested-by: Babu Moger Tested-by: Shaopeng Tan Tested-by: Tony Luck Link: https://lore.kernel.org/20250515165855.31452-18-james.morse@arm.com

x86/resctrl: Move the filesystem bits to headers visible to fs/resctrl

2025-05-16T09:35:23Z

Once the filesystem parts of resctrl move to fs/resctrl, it cannot rely on definitions in x86's internal.h. Move definitions in internal.h that need to be shared between the filesystem and architecture code to header files that fs/resctrl can include. Doing this separately means the filesystem code only moves between files of the same name, instead of having these changes mixed in too. Co-developed-by: Dave Martin Signed-off-by: Dave Martin Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Fenghua Yu Reviewed-by: Reinette Chatre Tested-by: Fenghua Yu Tested-by: Carl Worth # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Tested-by: Tony Luck Link: https://lore.kernel.org/20250515165855.31452-17-james.morse@arm.com

fs/resctrl: Add boiler plate for external resctrl code

2025-05-16T09:05:40Z

Add Makefile and Kconfig for fs/resctrl. Add ARCH_HAS_CPU_RESCTRL for the common parts of the resctrl interface and make X86_CPU_RESCTRL select this. Adding an include of asm/resctrl.h to linux/resctrl.h allows the /fs/resctrl files to switch over to using this header instead. Co-developed-by: Dave Martin Signed-off-by: Dave Martin Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Fenghua Yu Reviewed-by: Reinette Chatre Tested-by: Fenghua Yu Tested-by: Carl Worth # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Tested-by: Tony Luck Link: https://lore.kernel.org/20250515165855.31452-16-james.morse@arm.com

x86/resctrl: Drop init/exit on assorted symbols

2025-05-15T19:06:02Z

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 Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Tested-by: Fenghua Yu Tested-by: Carl Worth # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Tested-by: Tony Luck Link: https://lore.kernel.org/20250515165855.31452-10-james.morse@arm.com

x86/resctrl: Move get_config_index() to a header

2025-03-12T11:24:54Z

get_config_index() is used by the architecture specific code to map a CLOSID+type pair to an index in the configuration arrays. MPAM needs to do this too to preserve the ABI to user-space, there is no reason to do it differently. Move the helper to a header file to allow all architectures that either use or emulate CDP to use the same pattern of CLOSID values. Moving this to a header file means it must be marked inline, which matches the existing compiler choice for this static function. Co-developed-by: Dave Martin Signed-off-by: Dave Martin Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Fenghua Yu Reviewed-by: Reinette Chatre Reviewed-by: Babu Moger Tested-by: Carl Worth # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Babu Moger Link: https://lore.kernel.org/r/20250311183715.16445-30-james.morse@arm.com

x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr

2025-03-12T11:24:33Z

resctrl_arch_pseudo_lock_fn() has architecture specific behaviour, and takes a struct rdtgroup as an argument. After the filesystem code moves to /fs/, the definition of struct rdtgroup will not be available to the architecture code. The only reason resctrl_arch_pseudo_lock_fn() wants the rdtgroup is for the CLOSID. Embed that in the pseudo_lock_region as a closid, and move the definition of struct pseudo_lock_region to resctrl.h. Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Reviewed-by: Babu Moger Tested-by: Carl Worth # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Link: https://lore.kernel.org/r/20250311183715.16445-27-james.morse@arm.com

x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

2025-03-12T11:24:09Z

The mbm_cfg_mask field lists the bits that user-space can set when configuring an event. This value is output via the last_cmd_status file. Once the filesystem parts of resctrl are moved to live in /fs/, the struct rdt_hw_resource is inaccessible to the filesystem code. Because this value is output to user-space, it has to be accessible to the filesystem code. Move it to struct rdt_resource. Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Reviewed-by: Babu Moger Tested-by: Carl Worth # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Link: https://lore.kernel.org/r/20250311183715.16445-23-james.morse@arm.com

x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers

2025-03-12T11:23:49Z

mon_event_config_{read,write}() are called via IPI and access model specific registers to do their work. To support another architecture, this needs abstracting. Rename mon_event_config_{read,write}() to have a "resctrl_arch_" prefix, and move their struct mon_config_info parameter into . This allows another architecture to supply an implementation of these. As struct mon_config_info is now exposed globally, give it a 'resctrl_' prefix. MPAM systems need access to the domain to do this work, add the resource and domain to struct resctrl_mon_config_info. Co-developed-by: Dave Martin Signed-off-by: Dave Martin Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Reviewed-by: Babu Moger Tested-by: Carl Worth # arm64 Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Link: https://lore.kernel.org/r/20250311183715.16445-21-james.morse@arm.com