kernel/linux.git/include/linux/resctrl.h, branch v6.6.132

x86/resctrl: Add interface to write mbm_total_bytes_config

2023-01-23T16:40:30+00:00

The event configuration for mbm_total_bytes can be changed by the user by writing to the file /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config. The event configuration settings are domain specific and 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 ==== =========================================================== For example: To change the mbm_total_bytes to count only reads on domain 0, the bits 0, 1, 4 and 5 needs to be set, which is 110011b (in hex 0x33). Run the command: $echo 0=0x33 > /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config To change the mbm_total_bytes to count all the slow memory reads on domain 1, the bits 4 and 5 needs to be set which is 110000b (in hex 0x30). Run the command: $echo 1=0x30 > /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config Signed-off-by: Babu Moger Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Link: https://lore.kernel.org/r/20230113152039.770054-12-babu.moger@amd.com

x86/resctrl: Remove arch_has_empty_bitmaps

2022-10-24T08:30:29+00:00

The field arch_has_empty_bitmaps is not required anymore. The field min_cbm_bits is enough to validate the CBM (capacity bit mask) if the architecture can support the zero CBM or not. Suggested-by: Reinette Chatre Signed-off-by: Babu Moger Signed-off-by: Borislav Petkov Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Link: https://lore.kernel.org/r/166430979654.372014.615622285687642644.stgit@bmoger-ubuntu

x86/resctrl: Make resctrl_arch_rmid_read() return values in bytes

2022-09-23T12:25:05+00:00

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 Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-22-james.morse@arm.com

x86/resctrl: Add resctrl_rmid_realloc_limit to abstract x86's boot_cpu_data

2022-09-23T12:24:16+00:00

resctrl_rmid_realloc_threshold can be set by user-space. The maximum value is specified by the architecture. Currently max_threshold_occ_write() reads the maximum value from boot_cpu_data.x86_cache_size, which is not portable to another architecture. Add resctrl_rmid_realloc_limit to describe the maximum size in bytes that user-space can set the threshold to. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-21-james.morse@arm.com

x86/resctrl: Rename and change the units of resctrl_cqm_threshold

2022-09-23T12:23:41+00:00

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 Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-20-james.morse@arm.com

x86/resctrl: Pass the required parameters into resctrl_arch_rmid_read()

2022-09-23T12:21:25+00:00

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 hardware register. Currently the function returns the MBM values in chunks directly from hardware. To convert this to bytes, some correction and overflow calculations are needed. These depend on the resource and domain structures. Overflow detection requires the old chunks value. None of this is available to resctrl_arch_rmid_read(). MPAM requires the resource and domain structures to find the MMIO device that holds the registers. Pass the resource and domain to resctrl_arch_rmid_read(). This makes rmid_dirty() too big. Instead merge it with its only caller, and the name is kept as a local variable. Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-17-james.morse@arm.com

x86/resctrl: Abstract __rmid_read()

2022-09-23T12:17:20+00:00

__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 Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-16-james.morse@arm.com

x86/resctrl: Allow per-rmid arch private storage to be reset

2022-09-23T10:49:04+00:00

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 Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-15-james.morse@arm.com

x86/resctrl: Allow update_mba_bw() to update controls directly

2022-09-22T15:43:44+00:00

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 Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-12-james.morse@arm.com

x86/resctrl: Create mba_sc configuration in the rdt_domain

2022-09-22T15:17:59+00:00

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 Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-9-james.morse@arm.com