diff options
Diffstat (limited to 'drivers/resctrl')
| -rw-r--r-- | drivers/resctrl/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/resctrl/Makefile | 1 | ||||
| -rw-r--r-- | drivers/resctrl/mpam_devices.c | 303 | ||||
| -rw-r--r-- | drivers/resctrl/mpam_internal.h | 108 | ||||
| -rw-r--r-- | drivers/resctrl/mpam_resctrl.c | 1712 | ||||
| -rw-r--r-- | drivers/resctrl/test_mpam_resctrl.c | 315 |
6 files changed, 2403 insertions, 45 deletions
diff --git a/drivers/resctrl/Kconfig b/drivers/resctrl/Kconfig index c808e0470394..672abea3b03c 100644 --- a/drivers/resctrl/Kconfig +++ b/drivers/resctrl/Kconfig @@ -1,6 +1,7 @@ menuconfig ARM64_MPAM_DRIVER bool "MPAM driver" - depends on ARM64 && ARM64_MPAM && EXPERT + depends on ARM64 && ARM64_MPAM + select ACPI_MPAM if ACPI help Memory System Resource Partitioning and Monitoring (MPAM) driver for System IP, e.g. caches and memory controllers. @@ -22,3 +23,9 @@ config MPAM_KUNIT_TEST If unsure, say N. endif + +config ARM64_MPAM_RESCTRL_FS + bool + default y if ARM64_MPAM_DRIVER && RESCTRL_FS + select RESCTRL_RMID_DEPENDS_ON_CLOSID + select RESCTRL_ASSIGN_FIXED diff --git a/drivers/resctrl/Makefile b/drivers/resctrl/Makefile index 898199dcf80d..4f6d0e81f9b8 100644 --- a/drivers/resctrl/Makefile +++ b/drivers/resctrl/Makefile @@ -1,4 +1,5 @@ obj-$(CONFIG_ARM64_MPAM_DRIVER) += mpam.o mpam-y += mpam_devices.o +mpam-$(CONFIG_ARM64_MPAM_RESCTRL_FS) += mpam_resctrl.o ccflags-$(CONFIG_ARM64_MPAM_DRIVER_DEBUG) += -DDEBUG diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index 0666be6b0e88..41b14344b16f 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -29,7 +29,15 @@ #include "mpam_internal.h" -DEFINE_STATIC_KEY_FALSE(mpam_enabled); /* This moves to arch code */ +/* Values for the T241 errata workaround */ +#define T241_CHIPS_MAX 4 +#define T241_CHIP_NSLICES 12 +#define T241_SPARE_REG0_OFF 0x1b0000 +#define T241_SPARE_REG1_OFF 0x1c0000 +#define T241_CHIP_ID(phys) FIELD_GET(GENMASK_ULL(44, 43), phys) +#define T241_SHADOW_REG_OFF(sidx, pid) (0x360048 + (sidx) * 0x10000 + (pid) * 8) +#define SMCCC_SOC_ID_T241 0x036b0241 +static void __iomem *t241_scratch_regs[T241_CHIPS_MAX]; /* * mpam_list_lock protects the SRCU lists when writing. Once the @@ -76,6 +84,14 @@ static DECLARE_WORK(mpam_broken_work, &mpam_disable); static char *mpam_disable_reason; /* + * Whether resctrl has been setup. Used by cpuhp in preference to + * mpam_is_enabled(). The disable call after an error interrupt makes + * mpam_is_enabled() false before the cpuhp callbacks are made. + * Reads/writes should hold mpam_cpuhp_state_lock, (or be cpuhp callbacks). + */ +static bool mpam_resctrl_enabled; + +/* * An MSC is a physical container for controls and monitors, each identified by * their RIS index. These share a base-address, interrupts and some MMIO * registers. A vMSC is a virtual container for RIS in an MSC that control or @@ -624,6 +640,86 @@ static struct mpam_msc_ris *mpam_get_or_create_ris(struct mpam_msc *msc, return ERR_PTR(-ENOENT); } +static int mpam_enable_quirk_nvidia_t241_1(struct mpam_msc *msc, + const struct mpam_quirk *quirk) +{ + s32 soc_id = arm_smccc_get_soc_id_version(); + struct resource *r; + phys_addr_t phys; + + /* + * A mapping to a device other than the MSC is needed, check + * SOC_ID is NVIDIA T241 chip (036b:0241) + */ + if (soc_id < 0 || soc_id != SMCCC_SOC_ID_T241) + return -EINVAL; + + r = platform_get_resource(msc->pdev, IORESOURCE_MEM, 0); + if (!r) + return -EINVAL; + + /* Find the internal registers base addr from the CHIP ID */ + msc->t241_id = T241_CHIP_ID(r->start); + phys = FIELD_PREP(GENMASK_ULL(45, 44), msc->t241_id) | 0x19000000ULL; + + t241_scratch_regs[msc->t241_id] = ioremap(phys, SZ_8M); + if (WARN_ON_ONCE(!t241_scratch_regs[msc->t241_id])) + return -EINVAL; + + pr_info_once("Enabled workaround for NVIDIA T241 erratum T241-MPAM-1\n"); + + return 0; +} + +static const struct mpam_quirk mpam_quirks[] = { + { + /* NVIDIA t241 erratum T241-MPAM-1 */ + .init = mpam_enable_quirk_nvidia_t241_1, + .iidr = MPAM_IIDR_NVIDIA_T241, + .iidr_mask = MPAM_IIDR_MATCH_ONE, + .workaround = T241_SCRUB_SHADOW_REGS, + }, + { + /* NVIDIA t241 erratum T241-MPAM-4 */ + .iidr = MPAM_IIDR_NVIDIA_T241, + .iidr_mask = MPAM_IIDR_MATCH_ONE, + .workaround = T241_FORCE_MBW_MIN_TO_ONE, + }, + { + /* NVIDIA t241 erratum T241-MPAM-6 */ + .iidr = MPAM_IIDR_NVIDIA_T241, + .iidr_mask = MPAM_IIDR_MATCH_ONE, + .workaround = T241_MBW_COUNTER_SCALE_64, + }, + { + /* ARM CMN-650 CSU erratum 3642720 */ + .iidr = MPAM_IIDR_ARM_CMN_650, + .iidr_mask = MPAM_IIDR_MATCH_ONE, + .workaround = IGNORE_CSU_NRDY, + }, + { NULL } /* Sentinel */ +}; + +static void mpam_enable_quirks(struct mpam_msc *msc) +{ + const struct mpam_quirk *quirk; + + for (quirk = &mpam_quirks[0]; quirk->iidr_mask; quirk++) { + int err = 0; + + if (quirk->iidr != (msc->iidr & quirk->iidr_mask)) + continue; + + if (quirk->init) + err = quirk->init(msc, quirk); + + if (err) + continue; + + mpam_set_quirk(quirk->workaround, msc); + } +} + /* * IHI009A.a has this nugget: "If a monitor does not support automatic behaviour * of NRDY, software can use this bit for any purpose" - so hardware might not @@ -715,6 +811,13 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris) mpam_set_feature(mpam_feat_mbw_part, props); props->bwa_wd = FIELD_GET(MPAMF_MBW_IDR_BWA_WD, mbw_features); + + /* + * The BWA_WD field can represent 0-63, but the control fields it + * describes have a maximum of 16 bits. + */ + props->bwa_wd = min(props->bwa_wd, 16); + if (props->bwa_wd && FIELD_GET(MPAMF_MBW_IDR_HAS_MAX, mbw_features)) mpam_set_feature(mpam_feat_mbw_max, props); @@ -851,8 +954,11 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc) /* Grab an IDR value to find out how many RIS there are */ mutex_lock(&msc->part_sel_lock); idr = mpam_msc_read_idr(msc); + msc->iidr = mpam_read_partsel_reg(msc, IIDR); mutex_unlock(&msc->part_sel_lock); + mpam_enable_quirks(msc); + msc->ris_max = FIELD_GET(MPAMF_IDR_RIS_MAX, idr); /* Use these values so partid/pmg always starts with a valid value */ @@ -903,6 +1009,7 @@ struct mon_read { enum mpam_device_features type; u64 *val; int err; + bool waited_timeout; }; static bool mpam_ris_has_mbwu_long_counter(struct mpam_msc_ris *ris) @@ -1052,7 +1159,7 @@ static void write_msmon_ctl_flt_vals(struct mon_read *m, u32 ctl_val, } } -static u64 mpam_msmon_overflow_val(enum mpam_device_features type) +static u64 __mpam_msmon_overflow_val(enum mpam_device_features type) { /* TODO: implement scaling counters */ switch (type) { @@ -1067,6 +1174,18 @@ static u64 mpam_msmon_overflow_val(enum mpam_device_features type) } } +static u64 mpam_msmon_overflow_val(enum mpam_device_features type, + struct mpam_msc *msc) +{ + u64 overflow_val = __mpam_msmon_overflow_val(type); + + if (mpam_has_quirk(T241_MBW_COUNTER_SCALE_64, msc) && + type != mpam_feat_msmon_mbwu_63counter) + overflow_val *= 64; + + return overflow_val; +} + static void __ris_msmon_read(void *arg) { u64 now; @@ -1137,6 +1256,10 @@ static void __ris_msmon_read(void *arg) if (mpam_has_feature(mpam_feat_msmon_csu_hw_nrdy, rprops)) nrdy = now & MSMON___NRDY; now = FIELD_GET(MSMON___VALUE, now); + + if (mpam_has_quirk(IGNORE_CSU_NRDY, msc) && m->waited_timeout) + nrdy = false; + break; case mpam_feat_msmon_mbwu_31counter: case mpam_feat_msmon_mbwu_44counter: @@ -1157,13 +1280,17 @@ static void __ris_msmon_read(void *arg) now = FIELD_GET(MSMON___VALUE, now); } + if (mpam_has_quirk(T241_MBW_COUNTER_SCALE_64, msc) && + m->type != mpam_feat_msmon_mbwu_63counter) + now *= 64; + if (nrdy) break; mbwu_state = &ris->mbwu_state[ctx->mon]; if (overflow) - mbwu_state->correction += mpam_msmon_overflow_val(m->type); + mbwu_state->correction += mpam_msmon_overflow_val(m->type, msc); /* * Include bandwidth consumed before the last hardware reset and @@ -1270,6 +1397,7 @@ int mpam_msmon_read(struct mpam_component *comp, struct mon_cfg *ctx, .ctx = ctx, .type = type, .val = val, + .waited_timeout = true, }; *val = 0; @@ -1338,6 +1466,75 @@ static void mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd) __mpam_write_reg(msc, reg, bm); } +static void mpam_apply_t241_erratum(struct mpam_msc_ris *ris, u16 partid) +{ + int sidx, i, lcount = 1000; + void __iomem *regs; + u64 val0, val; + + regs = t241_scratch_regs[ris->vmsc->msc->t241_id]; + + for (i = 0; i < lcount; i++) { + /* Read the shadow register at index 0 */ + val0 = readq_relaxed(regs + T241_SHADOW_REG_OFF(0, partid)); + + /* Check if all the shadow registers have the same value */ + for (sidx = 1; sidx < T241_CHIP_NSLICES; sidx++) { + val = readq_relaxed(regs + + T241_SHADOW_REG_OFF(sidx, partid)); + if (val != val0) + break; + } + if (sidx == T241_CHIP_NSLICES) + break; + } + + if (i == lcount) + pr_warn_once("t241: inconsistent values in shadow regs"); + + /* Write a value zero to spare registers to take effect of MBW conf */ + writeq_relaxed(0, regs + T241_SPARE_REG0_OFF); + writeq_relaxed(0, regs + T241_SPARE_REG1_OFF); +} + +static void mpam_quirk_post_config_change(struct mpam_msc_ris *ris, u16 partid, + struct mpam_config *cfg) +{ + if (mpam_has_quirk(T241_SCRUB_SHADOW_REGS, ris->vmsc->msc)) + mpam_apply_t241_erratum(ris, partid); +} + +static u16 mpam_wa_t241_force_mbw_min_to_one(struct mpam_props *props) +{ + u16 max_hw_value, min_hw_granule, res0_bits; + + res0_bits = 16 - props->bwa_wd; + max_hw_value = ((1 << props->bwa_wd) - 1) << res0_bits; + min_hw_granule = ~max_hw_value; + + return min_hw_granule + 1; +} + +static u16 mpam_wa_t241_calc_min_from_max(struct mpam_props *props, + struct mpam_config *cfg) +{ + u16 val = 0; + u16 max; + u16 delta = ((5 * MPAMCFG_MBW_MAX_MAX) / 100) - 1; + + if (mpam_has_feature(mpam_feat_mbw_max, cfg)) { + max = cfg->mbw_max; + } else { + /* Resetting. Hence, use the ris specific default. */ + max = GENMASK(15, 16 - props->bwa_wd); + } + + if (max > delta) + val = max - delta; + + return val; +} + /* Called via IPI. Call while holding an SRCU reference */ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid, struct mpam_config *cfg) @@ -1364,36 +1561,41 @@ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid, __mpam_intpart_sel(ris->ris_idx, partid, msc); } - if (mpam_has_feature(mpam_feat_cpor_part, rprops) && - mpam_has_feature(mpam_feat_cpor_part, cfg)) { - if (cfg->reset_cpbm) - mpam_reset_msc_bitmap(msc, MPAMCFG_CPBM, rprops->cpbm_wd); - else + if (mpam_has_feature(mpam_feat_cpor_part, rprops)) { + if (mpam_has_feature(mpam_feat_cpor_part, cfg)) mpam_write_partsel_reg(msc, CPBM, cfg->cpbm); + else + mpam_reset_msc_bitmap(msc, MPAMCFG_CPBM, rprops->cpbm_wd); } - if (mpam_has_feature(mpam_feat_mbw_part, rprops) && - mpam_has_feature(mpam_feat_mbw_part, cfg)) { - if (cfg->reset_mbw_pbm) + if (mpam_has_feature(mpam_feat_mbw_part, rprops)) { + if (mpam_has_feature(mpam_feat_mbw_part, cfg)) mpam_reset_msc_bitmap(msc, MPAMCFG_MBW_PBM, rprops->mbw_pbm_bits); else mpam_write_partsel_reg(msc, MBW_PBM, cfg->mbw_pbm); } - if (mpam_has_feature(mpam_feat_mbw_min, rprops) && - mpam_has_feature(mpam_feat_mbw_min, cfg)) - mpam_write_partsel_reg(msc, MBW_MIN, 0); + if (mpam_has_feature(mpam_feat_mbw_min, rprops)) { + u16 val = 0; - if (mpam_has_feature(mpam_feat_mbw_max, rprops) && - mpam_has_feature(mpam_feat_mbw_max, cfg)) { - if (cfg->reset_mbw_max) - mpam_write_partsel_reg(msc, MBW_MAX, MPAMCFG_MBW_MAX_MAX); - else + if (mpam_has_quirk(T241_FORCE_MBW_MIN_TO_ONE, msc)) { + u16 min = mpam_wa_t241_force_mbw_min_to_one(rprops); + + val = mpam_wa_t241_calc_min_from_max(rprops, cfg); + val = max(val, min); + } + + mpam_write_partsel_reg(msc, MBW_MIN, val); + } + + if (mpam_has_feature(mpam_feat_mbw_max, rprops)) { + if (mpam_has_feature(mpam_feat_mbw_max, cfg)) mpam_write_partsel_reg(msc, MBW_MAX, cfg->mbw_max); + else + mpam_write_partsel_reg(msc, MBW_MAX, MPAMCFG_MBW_MAX_MAX); } - if (mpam_has_feature(mpam_feat_mbw_prop, rprops) && - mpam_has_feature(mpam_feat_mbw_prop, cfg)) + if (mpam_has_feature(mpam_feat_mbw_prop, rprops)) mpam_write_partsel_reg(msc, MBW_PROP, 0); if (mpam_has_feature(mpam_feat_cmax_cmax, rprops)) @@ -1421,6 +1623,8 @@ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid, mpam_write_partsel_reg(msc, PRI, pri_val); } + mpam_quirk_post_config_change(ris, partid, cfg); + mutex_unlock(&msc->part_sel_lock); } @@ -1493,16 +1697,6 @@ static int mpam_save_mbwu_state(void *arg) return 0; } -static void mpam_init_reset_cfg(struct mpam_config *reset_cfg) -{ - *reset_cfg = (struct mpam_config) { - .reset_cpbm = true, - .reset_mbw_pbm = true, - .reset_mbw_max = true, - }; - bitmap_fill(reset_cfg->features, MPAM_FEATURE_LAST); -} - /* * Called via smp_call_on_cpu() to prevent migration, while still being * pre-emptible. Caller must hold mpam_srcu. @@ -1510,14 +1704,12 @@ static void mpam_init_reset_cfg(struct mpam_config *reset_cfg) static int mpam_reset_ris(void *arg) { u16 partid, partid_max; - struct mpam_config reset_cfg; + struct mpam_config reset_cfg = {}; struct mpam_msc_ris *ris = arg; if (ris->in_reset_state) return 0; - mpam_init_reset_cfg(&reset_cfg); - spin_lock(&partid_max_lock); partid_max = mpam_partid_max; spin_unlock(&partid_max_lock); @@ -1632,6 +1824,9 @@ static int mpam_cpu_online(unsigned int cpu) mpam_reprogram_msc(msc); } + if (mpam_resctrl_enabled) + return mpam_resctrl_online_cpu(cpu); + return 0; } @@ -1675,6 +1870,9 @@ static int mpam_cpu_offline(unsigned int cpu) { struct mpam_msc *msc; + if (mpam_resctrl_enabled) + mpam_resctrl_offline_cpu(cpu); + guard(srcu)(&mpam_srcu); list_for_each_entry_srcu(msc, &mpam_all_msc, all_msc_list, srcu_read_lock_held(&mpam_srcu)) { @@ -1971,6 +2169,7 @@ static bool mpam_has_cmax_wd_feature(struct mpam_props *props) * resulting safe value must be compatible with both. When merging values in * the tree, all the aliasing resources must be handled first. * On mismatch, parent is modified. + * Quirks on an MSC will apply to all MSC in that class. */ static void __props_mismatch(struct mpam_props *parent, struct mpam_props *child, bool alias) @@ -2090,6 +2289,7 @@ static void __props_mismatch(struct mpam_props *parent, * nobble the class feature, as we can't configure all the resources. * e.g. The L3 cache is composed of two resources with 13 and 17 portion * bitmaps respectively. + * Quirks on an MSC will apply to all MSC in that class. */ static void __class_props_mismatch(struct mpam_class *class, struct mpam_vmsc *vmsc) @@ -2103,6 +2303,9 @@ __class_props_mismatch(struct mpam_class *class, struct mpam_vmsc *vmsc) dev_dbg(dev, "Merging features for class:0x%lx &= vmsc:0x%lx\n", (long)cprops->features, (long)vprops->features); + /* Merge quirks */ + class->quirks |= vmsc->msc->quirks; + /* Take the safe value for any common features */ __props_mismatch(cprops, vprops, false); } @@ -2167,6 +2370,9 @@ static void mpam_enable_merge_class_features(struct mpam_component *comp) list_for_each_entry(vmsc, &comp->vmsc, comp_list) __class_props_mismatch(class, vmsc); + + if (mpam_has_quirk(T241_FORCE_MBW_MIN_TO_ONE, class)) + mpam_clear_feature(mpam_feat_mbw_min, &class->props); } /* @@ -2520,6 +2726,12 @@ static void mpam_enable_once(void) mutex_unlock(&mpam_list_lock); cpus_read_unlock(); + if (!err) { + err = mpam_resctrl_setup(); + if (err) + pr_err("Failed to initialise resctrl: %d\n", err); + } + if (err) { mpam_disable_reason = "Failed to enable."; schedule_work(&mpam_broken_work); @@ -2527,6 +2739,7 @@ static void mpam_enable_once(void) } static_branch_enable(&mpam_enabled); + mpam_resctrl_enabled = true; mpam_register_cpuhp_callbacks(mpam_cpu_online, mpam_cpu_offline, "mpam:online"); @@ -2559,7 +2772,7 @@ static void mpam_reset_component_locked(struct mpam_component *comp) } } -static void mpam_reset_class_locked(struct mpam_class *class) +void mpam_reset_class_locked(struct mpam_class *class) { struct mpam_component *comp; @@ -2586,24 +2799,39 @@ static void mpam_reset_class(struct mpam_class *class) void mpam_disable(struct work_struct *ignored) { int idx; + bool do_resctrl_exit; struct mpam_class *class; struct mpam_msc *msc, *tmp; + if (mpam_is_enabled()) + static_branch_disable(&mpam_enabled); + mutex_lock(&mpam_cpuhp_state_lock); if (mpam_cpuhp_state) { cpuhp_remove_state(mpam_cpuhp_state); mpam_cpuhp_state = 0; } + + /* + * Removing the cpuhp state called mpam_cpu_offline() and told resctrl + * all the CPUs are offline. + */ + do_resctrl_exit = mpam_resctrl_enabled; + mpam_resctrl_enabled = false; mutex_unlock(&mpam_cpuhp_state_lock); - static_branch_disable(&mpam_enabled); + if (do_resctrl_exit) + mpam_resctrl_exit(); mpam_unregister_irqs(); idx = srcu_read_lock(&mpam_srcu); list_for_each_entry_srcu(class, &mpam_classes, classes_list, - srcu_read_lock_held(&mpam_srcu)) + srcu_read_lock_held(&mpam_srcu)) { mpam_reset_class(class); + if (do_resctrl_exit) + mpam_resctrl_teardown_class(class); + } srcu_read_unlock(&mpam_srcu, idx); mutex_lock(&mpam_list_lock); @@ -2694,6 +2922,7 @@ int mpam_apply_config(struct mpam_component *comp, u16 partid, srcu_read_lock_held(&mpam_srcu)) { arg.ris = ris; mpam_touch_msc(msc, __write_config, &arg); + ris->in_reset_state = false; } mutex_unlock(&msc->cfg_lock); } diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h index e8971842b124..1914aefdcba9 100644 --- a/drivers/resctrl/mpam_internal.h +++ b/drivers/resctrl/mpam_internal.h @@ -12,22 +12,31 @@ #include <linux/jump_label.h> #include <linux/llist.h> #include <linux/mutex.h> +#include <linux/resctrl.h> #include <linux/spinlock.h> #include <linux/srcu.h> #include <linux/types.h> +#include <asm/mpam.h> + #define MPAM_MSC_MAX_NUM_RIS 16 struct platform_device; -DECLARE_STATIC_KEY_FALSE(mpam_enabled); - #ifdef CONFIG_MPAM_KUNIT_TEST #define PACKED_FOR_KUNIT __packed #else #define PACKED_FOR_KUNIT #endif +/* + * This 'mon' values must not alias an actual monitor, so must be larger than + * U16_MAX, but not be confused with an errno value, so smaller than + * (u32)-SZ_4K. + * USE_PRE_ALLOCATED is used to avoid confusion with an actual monitor. + */ +#define USE_PRE_ALLOCATED (U16_MAX + 1) + static inline bool mpam_is_enabled(void) { return static_branch_likely(&mpam_enabled); @@ -76,6 +85,8 @@ struct mpam_msc { u8 pmg_max; unsigned long ris_idxs; u32 ris_max; + u32 iidr; + u16 quirks; /* * error_irq_lock is taken when registering/unregistering the error @@ -119,6 +130,9 @@ struct mpam_msc { void __iomem *mapped_hwpage; size_t mapped_hwpage_sz; + /* Values only used on some platforms for quirks */ + u32 t241_id; + struct mpam_garbage garbage; }; @@ -207,6 +221,42 @@ struct mpam_props { #define mpam_set_feature(_feat, x) __set_bit(_feat, (x)->features) #define mpam_clear_feature(_feat, x) __clear_bit(_feat, (x)->features) +/* Workaround bits for msc->quirks */ +enum mpam_device_quirks { + T241_SCRUB_SHADOW_REGS, + T241_FORCE_MBW_MIN_TO_ONE, + T241_MBW_COUNTER_SCALE_64, + IGNORE_CSU_NRDY, + MPAM_QUIRK_LAST +}; + +#define mpam_has_quirk(_quirk, x) ((1 << (_quirk) & (x)->quirks)) +#define mpam_set_quirk(_quirk, x) ((x)->quirks |= (1 << (_quirk))) + +struct mpam_quirk { + int (*init)(struct mpam_msc *msc, const struct mpam_quirk *quirk); + + u32 iidr; + u32 iidr_mask; + + enum mpam_device_quirks workaround; +}; + +#define MPAM_IIDR_MATCH_ONE (FIELD_PREP_CONST(MPAMF_IIDR_PRODUCTID, 0xfff) | \ + FIELD_PREP_CONST(MPAMF_IIDR_VARIANT, 0xf) | \ + FIELD_PREP_CONST(MPAMF_IIDR_REVISION, 0xf) | \ + FIELD_PREP_CONST(MPAMF_IIDR_IMPLEMENTER, 0xfff)) + +#define MPAM_IIDR_NVIDIA_T241 (FIELD_PREP_CONST(MPAMF_IIDR_PRODUCTID, 0x241) | \ + FIELD_PREP_CONST(MPAMF_IIDR_VARIANT, 0) | \ + FIELD_PREP_CONST(MPAMF_IIDR_REVISION, 0) | \ + FIELD_PREP_CONST(MPAMF_IIDR_IMPLEMENTER, 0x36b)) + +#define MPAM_IIDR_ARM_CMN_650 (FIELD_PREP_CONST(MPAMF_IIDR_PRODUCTID, 0) | \ + FIELD_PREP_CONST(MPAMF_IIDR_VARIANT, 0) | \ + FIELD_PREP_CONST(MPAMF_IIDR_REVISION, 0) | \ + FIELD_PREP_CONST(MPAMF_IIDR_IMPLEMENTER, 0x43b)) + /* The values for MSMON_CFG_MBWU_FLT.RWBW */ enum mon_filter_options { COUNT_BOTH = 0, @@ -215,7 +265,11 @@ enum mon_filter_options { }; struct mon_cfg { - u16 mon; + /* + * mon must be large enough to hold out of range values like + * USE_PRE_ALLOCATED + */ + u32 mon; u8 pmg; bool match_pmg; bool csu_exclude_clean; @@ -246,6 +300,7 @@ struct mpam_class { struct mpam_props props; u32 nrdy_usec; + u16 quirks; u8 level; enum mpam_class_types type; @@ -266,10 +321,6 @@ struct mpam_config { u32 mbw_pbm; u16 mbw_max; - bool reset_cpbm; - bool reset_mbw_pbm; - bool reset_mbw_max; - struct mpam_garbage garbage; }; @@ -337,6 +388,32 @@ struct mpam_msc_ris { struct mpam_garbage garbage; }; +struct mpam_resctrl_dom { + struct mpam_component *ctrl_comp; + + /* + * There is no single mon_comp because different events may be backed + * by different class/components. mon_comp is indexed by the event + * number. + */ + struct mpam_component *mon_comp[QOS_NUM_EVENTS]; + + struct rdt_ctrl_domain resctrl_ctrl_dom; + struct rdt_l3_mon_domain resctrl_mon_dom; +}; + +struct mpam_resctrl_res { + struct mpam_class *class; + struct rdt_resource resctrl_res; + bool cdp_enabled; +}; + +struct mpam_resctrl_mon { + struct mpam_class *class; + + /* per-class data that resctrl needs will live here */ +}; + static inline int mpam_alloc_csu_mon(struct mpam_class *class) { struct mpam_props *cprops = &class->props; @@ -381,6 +458,9 @@ extern u8 mpam_pmg_max; void mpam_enable(struct work_struct *work); void mpam_disable(struct work_struct *work); +/* Reset all the RIS in a class under cpus_read_lock() */ +void mpam_reset_class_locked(struct mpam_class *class); + int mpam_apply_config(struct mpam_component *comp, u16 partid, struct mpam_config *cfg); @@ -391,6 +471,20 @@ void mpam_msmon_reset_mbwu(struct mpam_component *comp, struct mon_cfg *ctx); int mpam_get_cpumask_from_cache_id(unsigned long cache_id, u32 cache_level, cpumask_t *affinity); +#ifdef CONFIG_RESCTRL_FS +int mpam_resctrl_setup(void); +void mpam_resctrl_exit(void); +int mpam_resctrl_online_cpu(unsigned int cpu); +void mpam_resctrl_offline_cpu(unsigned int cpu); +void mpam_resctrl_teardown_class(struct mpam_class *class); +#else +static inline int mpam_resctrl_setup(void) { return 0; } +static inline void mpam_resctrl_exit(void) { } +static inline int mpam_resctrl_online_cpu(unsigned int cpu) { return 0; } +static inline void mpam_resctrl_offline_cpu(unsigned int cpu) { } +static inline void mpam_resctrl_teardown_class(struct mpam_class *class) { } +#endif /* CONFIG_RESCTRL_FS */ + /* * MPAM MSCs have the following register layout. See: * Arm Memory System Resource Partitioning and Monitoring (MPAM) System diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c new file mode 100644 index 000000000000..226ff6f532fa --- /dev/null +++ b/drivers/resctrl/mpam_resctrl.c @@ -0,0 +1,1712 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2025 Arm Ltd. + +#define pr_fmt(fmt) "%s:%s: " fmt, KBUILD_MODNAME, __func__ + +#include <linux/arm_mpam.h> +#include <linux/cacheinfo.h> +#include <linux/cpu.h> +#include <linux/cpumask.h> +#include <linux/errno.h> +#include <linux/limits.h> +#include <linux/list.h> +#include <linux/math.h> +#include <linux/printk.h> +#include <linux/rculist.h> +#include <linux/resctrl.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/wait.h> + +#include <asm/mpam.h> + +#include "mpam_internal.h" + +static DECLARE_WAIT_QUEUE_HEAD(resctrl_mon_ctx_waiters); + +/* + * The classes we've picked to map to resctrl resources, wrapped + * in with their resctrl structure. + * Class pointer may be NULL. + */ +static struct mpam_resctrl_res mpam_resctrl_controls[RDT_NUM_RESOURCES]; + +#define for_each_mpam_resctrl_control(res, rid) \ + for (rid = 0, res = &mpam_resctrl_controls[rid]; \ + rid < RDT_NUM_RESOURCES; \ + rid++, res = &mpam_resctrl_controls[rid]) + +/* + * The classes we've picked to map to resctrl events. + * Resctrl believes all the worlds a Xeon, and these are all on the L3. This + * array lets us find the actual class backing the event counters. e.g. + * the only memory bandwidth counters may be on the memory controller, but to + * make use of them, we pretend they are on L3. Restrict the events considered + * to those supported by MPAM. + * Class pointer may be NULL. + */ +#define MPAM_MAX_EVENT QOS_L3_MBM_TOTAL_EVENT_ID +static struct mpam_resctrl_mon mpam_resctrl_counters[MPAM_MAX_EVENT + 1]; + +#define for_each_mpam_resctrl_mon(mon, eventid) \ + for (eventid = QOS_FIRST_EVENT, mon = &mpam_resctrl_counters[eventid]; \ + eventid <= MPAM_MAX_EVENT; \ + eventid++, mon = &mpam_resctrl_counters[eventid]) + +/* The lock for modifying resctrl's domain lists from cpuhp callbacks. */ +static DEFINE_MUTEX(domain_list_lock); + +/* + * MPAM emulates CDP by setting different PARTID in the I/D fields of MPAM0_EL1. + * This applies globally to all traffic the CPU generates. + */ +static bool cdp_enabled; + +/* + * We use cacheinfo to discover the size of the caches and their id. cacheinfo + * populates this from a device_initcall(). mpam_resctrl_setup() must wait. + */ +static bool cacheinfo_ready; +static DECLARE_WAIT_QUEUE_HEAD(wait_cacheinfo_ready); + +/* + * If resctrl_init() succeeded, resctrl_exit() can be used to remove support + * for the filesystem in the event of an error. + */ +static bool resctrl_enabled; + +bool resctrl_arch_alloc_capable(void) +{ + struct mpam_resctrl_res *res; + enum resctrl_res_level rid; + + for_each_mpam_resctrl_control(res, rid) { + if (res->resctrl_res.alloc_capable) + return true; + } + + return false; +} + +bool resctrl_arch_mon_capable(void) +{ + struct mpam_resctrl_res *res = &mpam_resctrl_controls[RDT_RESOURCE_L3]; + struct rdt_resource *l3 = &res->resctrl_res; + + /* All monitors are presented as being on the L3 cache */ + return l3->mon_capable; +} + +bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt) +{ + return false; +} + +void resctrl_arch_mon_event_config_read(void *info) +{ +} + +void resctrl_arch_mon_event_config_write(void *info) +{ +} + +void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_l3_mon_domain *d) +{ +} + +void resctrl_arch_reset_rmid(struct rdt_resource *r, struct rdt_l3_mon_domain *d, + u32 closid, u32 rmid, enum resctrl_event_id eventid) +{ +} + +void resctrl_arch_reset_cntr(struct rdt_resource *r, struct rdt_l3_mon_domain *d, + u32 closid, u32 rmid, int cntr_id, + enum resctrl_event_id eventid) +{ +} + +void resctrl_arch_config_cntr(struct rdt_resource *r, struct rdt_l3_mon_domain *d, + enum resctrl_event_id evtid, u32 rmid, u32 closid, + u32 cntr_id, bool assign) +{ +} + +int resctrl_arch_cntr_read(struct rdt_resource *r, struct rdt_l3_mon_domain *d, + u32 unused, u32 rmid, int cntr_id, + enum resctrl_event_id eventid, u64 *val) +{ + return -EOPNOTSUPP; +} + +bool resctrl_arch_mbm_cntr_assign_enabled(struct rdt_resource *r) +{ + return false; +} + +int resctrl_arch_mbm_cntr_assign_set(struct rdt_resource *r, bool enable) +{ + return -EINVAL; +} + +int resctrl_arch_io_alloc_enable(struct rdt_resource *r, bool enable) +{ + return -EOPNOTSUPP; +} + +bool resctrl_arch_get_io_alloc_enabled(struct rdt_resource *r) +{ + return false; +} + +void resctrl_arch_pre_mount(void) +{ +} + +bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level rid) +{ + return mpam_resctrl_controls[rid].cdp_enabled; +} + +/** + * resctrl_reset_task_closids() - Reset the PARTID/PMG values for all tasks. + * + * At boot, all existing tasks use partid zero for D and I. + * To enable/disable CDP emulation, all these tasks need relabelling. + */ +static void resctrl_reset_task_closids(void) +{ + struct task_struct *p, *t; + + read_lock(&tasklist_lock); + for_each_process_thread(p, t) { + resctrl_arch_set_closid_rmid(t, RESCTRL_RESERVED_CLOSID, + RESCTRL_RESERVED_RMID); + } + read_unlock(&tasklist_lock); +} + +int resctrl_arch_set_cdp_enabled(enum resctrl_res_level rid, bool enable) +{ + u32 partid_i = RESCTRL_RESERVED_CLOSID, partid_d = RESCTRL_RESERVED_CLOSID; + struct mpam_resctrl_res *res = &mpam_resctrl_controls[RDT_RESOURCE_L3]; + struct rdt_resource *l3 = &res->resctrl_res; + int cpu; + + if (!IS_ENABLED(CONFIG_EXPERT) && enable) { + /* + * If the resctrl fs is mounted more than once, sequentially, + * then CDP can lead to the use of out of range PARTIDs. + */ + pr_warn("CDP not supported\n"); + return -EOPNOTSUPP; + } + + if (enable) + pr_warn("CDP is an expert feature and may cause MPAM to malfunction.\n"); + + /* + * resctrl_arch_set_cdp_enabled() is only called with enable set to + * false on error and unmount. + */ + cdp_enabled = enable; + mpam_resctrl_controls[rid].cdp_enabled = enable; + + if (enable) + l3->mon.num_rmid = resctrl_arch_system_num_rmid_idx() / 2; + else + l3->mon.num_rmid = resctrl_arch_system_num_rmid_idx(); + + /* The mbw_max feature can't hide cdp as it's a per-partid maximum. */ + if (cdp_enabled && !mpam_resctrl_controls[RDT_RESOURCE_MBA].cdp_enabled) + mpam_resctrl_controls[RDT_RESOURCE_MBA].resctrl_res.alloc_capable = false; + + /* + * If resctrl has attempted to enable CDP on MBA, re-enable MBA as two + * configurations will be provided so there is no aliasing problem. + */ + if (mpam_resctrl_controls[RDT_RESOURCE_MBA].cdp_enabled && + mpam_resctrl_controls[RDT_RESOURCE_MBA].class) + mpam_resctrl_controls[RDT_RESOURCE_MBA].resctrl_res.alloc_capable = true; + + /* On unmount when CDP is disabled, re-enable MBA */ + if (!cdp_enabled && mpam_resctrl_controls[RDT_RESOURCE_MBA].class) + mpam_resctrl_controls[RDT_RESOURCE_MBA].resctrl_res.alloc_capable = true; + + if (enable) { + if (mpam_partid_max < 1) + return -EINVAL; + + partid_d = resctrl_get_config_index(RESCTRL_RESERVED_CLOSID, CDP_DATA); + partid_i = resctrl_get_config_index(RESCTRL_RESERVED_CLOSID, CDP_CODE); + } + + mpam_set_task_partid_pmg(current, partid_d, partid_i, 0, 0); + WRITE_ONCE(arm64_mpam_global_default, mpam_get_regval(current)); + + resctrl_reset_task_closids(); + + for_each_possible_cpu(cpu) + mpam_set_cpu_defaults(cpu, partid_d, partid_i, 0, 0); + on_each_cpu(resctrl_arch_sync_cpu_closid_rmid, NULL, 1); + + return 0; +} + +static bool mpam_resctrl_hide_cdp(enum resctrl_res_level rid) +{ + return cdp_enabled && !resctrl_arch_get_cdp_enabled(rid); +} + +/* + * MSC may raise an error interrupt if it sees an out or range partid/pmg, + * and go on to truncate the value. Regardless of what the hardware supports, + * only the system wide safe value is safe to use. + */ +u32 resctrl_arch_get_num_closid(struct rdt_resource *ignored) +{ + return mpam_partid_max + 1; +} + +u32 resctrl_arch_system_num_rmid_idx(void) +{ + return (mpam_pmg_max + 1) * (mpam_partid_max + 1); +} + +u32 resctrl_arch_rmid_idx_encode(u32 closid, u32 rmid) +{ + return closid * (mpam_pmg_max + 1) + rmid; +} + +void resctrl_arch_rmid_idx_decode(u32 idx, u32 *closid, u32 *rmid) +{ + *closid = idx / (mpam_pmg_max + 1); + *rmid = idx % (mpam_pmg_max + 1); +} + +void resctrl_arch_sched_in(struct task_struct *tsk) +{ + lockdep_assert_preemption_disabled(); + + mpam_thread_switch(tsk); +} + +void resctrl_arch_set_cpu_default_closid_rmid(int cpu, u32 closid, u32 rmid) +{ + WARN_ON_ONCE(closid > U16_MAX); + WARN_ON_ONCE(rmid > U8_MAX); + + if (!cdp_enabled) { + mpam_set_cpu_defaults(cpu, closid, closid, rmid, rmid); + } else { + /* + * When CDP is enabled, resctrl halves the closid range and we + * use odd/even partid for one closid. + */ + u32 partid_d = resctrl_get_config_index(closid, CDP_DATA); + u32 partid_i = resctrl_get_config_index(closid, CDP_CODE); + + mpam_set_cpu_defaults(cpu, partid_d, partid_i, rmid, rmid); + } +} + +void resctrl_arch_sync_cpu_closid_rmid(void *info) +{ + struct resctrl_cpu_defaults *r = info; + + lockdep_assert_preemption_disabled(); + + if (r) { + resctrl_arch_set_cpu_default_closid_rmid(smp_processor_id(), + r->closid, r->rmid); + } + + resctrl_arch_sched_in(current); +} + +void resctrl_arch_set_closid_rmid(struct task_struct *tsk, u32 closid, u32 rmid) +{ + WARN_ON_ONCE(closid > U16_MAX); + WARN_ON_ONCE(rmid > U8_MAX); + + if (!cdp_enabled) { + mpam_set_task_partid_pmg(tsk, closid, closid, rmid, rmid); + } else { + u32 partid_d = resctrl_get_config_index(closid, CDP_DATA); + u32 partid_i = resctrl_get_config_index(closid, CDP_CODE); + + mpam_set_task_partid_pmg(tsk, partid_d, partid_i, rmid, rmid); + } +} + +bool resctrl_arch_match_closid(struct task_struct *tsk, u32 closid) +{ + u64 regval = mpam_get_regval(tsk); + u32 tsk_closid = FIELD_GET(MPAM0_EL1_PARTID_D, regval); + + if (cdp_enabled) + tsk_closid >>= 1; + + return tsk_closid == closid; +} + +/* The task's pmg is not unique, the partid must be considered too */ +bool resctrl_arch_match_rmid(struct task_struct *tsk, u32 closid, u32 rmid) +{ + u64 regval = mpam_get_regval(tsk); + u32 tsk_closid = FIELD_GET(MPAM0_EL1_PARTID_D, regval); + u32 tsk_rmid = FIELD_GET(MPAM0_EL1_PMG_D, regval); + + if (cdp_enabled) + tsk_closid >>= 1; + + return (tsk_closid == closid) && (tsk_rmid == rmid); +} + +struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l) +{ + if (l >= RDT_NUM_RESOURCES) + return NULL; + + return &mpam_resctrl_controls[l].resctrl_res; +} + +static int resctrl_arch_mon_ctx_alloc_no_wait(enum resctrl_event_id evtid) +{ + struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[evtid]; + + if (!mpam_is_enabled()) + return -EINVAL; + + if (!mon->class) + return -EINVAL; + + switch (evtid) { + case QOS_L3_OCCUP_EVENT_ID: + /* With CDP, one monitor gets used for both code/data reads */ + return mpam_alloc_csu_mon(mon->class); + case QOS_L3_MBM_LOCAL_EVENT_ID: + case QOS_L3_MBM_TOTAL_EVENT_ID: + return USE_PRE_ALLOCATED; + default: + return -EOPNOTSUPP; + } +} + +void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, + enum resctrl_event_id evtid) +{ + DEFINE_WAIT(wait); + int *ret; + + ret = kmalloc_obj(*ret); + if (!ret) + return ERR_PTR(-ENOMEM); + + do { + prepare_to_wait(&resctrl_mon_ctx_waiters, &wait, + TASK_INTERRUPTIBLE); + *ret = resctrl_arch_mon_ctx_alloc_no_wait(evtid); + if (*ret == -ENOSPC) + schedule(); + } while (*ret == -ENOSPC && !signal_pending(current)); + finish_wait(&resctrl_mon_ctx_waiters, &wait); + + return ret; +} + +static void resctrl_arch_mon_ctx_free_no_wait(enum resctrl_event_id evtid, + u32 mon_idx) +{ + struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[evtid]; + + if (!mpam_is_enabled()) + return; + + if (!mon->class) + return; + + if (evtid == QOS_L3_OCCUP_EVENT_ID) + mpam_free_csu_mon(mon->class, mon_idx); + + wake_up(&resctrl_mon_ctx_waiters); +} + +void resctrl_arch_mon_ctx_free(struct rdt_resource *r, + enum resctrl_event_id evtid, void *arch_mon_ctx) +{ + u32 mon_idx = *(u32 *)arch_mon_ctx; + + kfree(arch_mon_ctx); + + resctrl_arch_mon_ctx_free_no_wait(evtid, mon_idx); +} + +static int __read_mon(struct mpam_resctrl_mon *mon, struct mpam_component *mon_comp, + enum mpam_device_features mon_type, + int mon_idx, + enum resctrl_conf_type cdp_type, u32 closid, u32 rmid, u64 *val) +{ + struct mon_cfg cfg; + + if (!mpam_is_enabled()) + return -EINVAL; + + /* Shift closid to account for CDP */ + closid = resctrl_get_config_index(closid, cdp_type); + + if (irqs_disabled()) { + /* Check if we can access this domain without an IPI */ + return -EIO; + } + + cfg = (struct mon_cfg) { + .mon = mon_idx, + .match_pmg = true, + .partid = closid, + .pmg = rmid, + }; + + return mpam_msmon_read(mon_comp, &cfg, mon_type, val); +} + +static int read_mon_cdp_safe(struct mpam_resctrl_mon *mon, struct mpam_component *mon_comp, + enum mpam_device_features mon_type, + int mon_idx, u32 closid, u32 rmid, u64 *val) +{ + if (cdp_enabled) { + u64 code_val = 0, data_val = 0; + int err; + + err = __read_mon(mon, mon_comp, mon_type, mon_idx, + CDP_CODE, closid, rmid, &code_val); + if (err) + return err; + + err = __read_mon(mon, mon_comp, mon_type, mon_idx, + CDP_DATA, closid, rmid, &data_val); + if (err) + return err; + + *val += code_val + data_val; + return 0; + } + + return __read_mon(mon, mon_comp, mon_type, mon_idx, + CDP_NONE, closid, rmid, val); +} + +/* MBWU when not in ABMC mode (not supported), and CSU counters. */ +int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain_hdr *hdr, + u32 closid, u32 rmid, enum resctrl_event_id eventid, + void *arch_priv, u64 *val, void *arch_mon_ctx) +{ + struct mpam_resctrl_dom *l3_dom; + struct mpam_component *mon_comp; + u32 mon_idx = *(u32 *)arch_mon_ctx; + enum mpam_device_features mon_type; + struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[eventid]; + + resctrl_arch_rmid_read_context_check(); + + if (!mpam_is_enabled()) + return -EINVAL; + + if (eventid >= QOS_NUM_EVENTS || !mon->class) + return -EINVAL; + + l3_dom = container_of(hdr, struct mpam_resctrl_dom, resctrl_mon_dom.hdr); + mon_comp = l3_dom->mon_comp[eventid]; + + if (eventid != QOS_L3_OCCUP_EVENT_ID) + return -EINVAL; + + mon_type = mpam_feat_msmon_csu; + + return read_mon_cdp_safe(mon, mon_comp, mon_type, mon_idx, + closid, rmid, val); +} + +/* + * The rmid realloc threshold should be for the smallest cache exposed to + * resctrl. + */ +static int update_rmid_limits(struct mpam_class *class) +{ + u32 num_unique_pmg = resctrl_arch_system_num_rmid_idx(); + struct mpam_props *cprops = &class->props; + struct cacheinfo *ci; + + lockdep_assert_cpus_held(); + + if (!mpam_has_feature(mpam_feat_msmon_csu, cprops)) + return 0; + + /* + * Assume cache levels are the same size for all CPUs... + * The check just requires any online CPU and it can't go offline as we + * hold the cpu lock. + */ + ci = get_cpu_cacheinfo_level(raw_smp_processor_id(), class->level); + if (!ci || ci->size == 0) { + pr_debug("Could not read cache size for class %u\n", + class->level); + return -EINVAL; + } + + if (!resctrl_rmid_realloc_limit || + ci->size < resctrl_rmid_realloc_limit) { + resctrl_rmid_realloc_limit = ci->size; + resctrl_rmid_realloc_threshold = ci->size / num_unique_pmg; + } + + return 0; +} + +static bool cache_has_usable_cpor(struct mpam_class *class) +{ + struct mpam_props *cprops = &class->props; + + if (!mpam_has_feature(mpam_feat_cpor_part, cprops)) + return false; + + /* resctrl uses u32 for all bitmap configurations */ + return class->props.cpbm_wd <= 32; +} + +static bool mba_class_use_mbw_max(struct mpam_props *cprops) +{ + return (mpam_has_feature(mpam_feat_mbw_max, cprops) && + cprops->bwa_wd); +} + +static bool class_has_usable_mba(struct mpam_props *cprops) +{ + return mba_class_use_mbw_max(cprops); +} + +static bool cache_has_usable_csu(struct mpam_class *class) +{ + struct mpam_props *cprops; + + if (!class) + return false; + + cprops = &class->props; + + if (!mpam_has_feature(mpam_feat_msmon_csu, cprops)) + return false; + + /* + * CSU counters settle on the value, so we can get away with + * having only one. + */ + if (!cprops->num_csu_mon) + return false; + + return true; +} + +/* + * Calculate the worst-case percentage change from each implemented step + * in the control. + */ +static u32 get_mba_granularity(struct mpam_props *cprops) +{ + if (!mba_class_use_mbw_max(cprops)) + return 0; + + /* + * bwa_wd is the number of bits implemented in the 0.xxx + * fixed point fraction. 1 bit is 50%, 2 is 25% etc. + */ + return DIV_ROUND_UP(MAX_MBA_BW, 1 << cprops->bwa_wd); +} + +/* + * Each fixed-point hardware value architecturally represents a range + * of values: the full range 0% - 100% is split contiguously into + * (1 << cprops->bwa_wd) equal bands. + * + * Although the bwa_bwd fields have 6 bits the maximum valid value is 16 + * as it reports the width of fields that are at most 16 bits. When + * fewer than 16 bits are valid the least significant bits are + * ignored. The implied binary point is kept between bits 15 and 16 and + * so the valid bits are leftmost. + * + * See ARM IHI0099B.a "MPAM system component specification", Section 9.3, + * "The fixed-point fractional format" for more information. + * + * Find the nearest percentage value to the upper bound of the selected band: + */ +static u32 mbw_max_to_percent(u16 mbw_max, struct mpam_props *cprops) +{ + u32 val = mbw_max; + + val >>= 16 - cprops->bwa_wd; + val += 1; + val *= MAX_MBA_BW; + val = DIV_ROUND_CLOSEST(val, 1 << cprops->bwa_wd); + + return val; +} + +/* + * Find the band whose upper bound is closest to the specified percentage. + * + * A round-to-nearest policy is followed here as a balanced compromise + * between unexpected under-commit of the resource (where the total of + * a set of resource allocations after conversion is less than the + * expected total, due to rounding of the individual converted + * percentages) and over-commit (where the total of the converted + * allocations is greater than expected). + */ +static u16 percent_to_mbw_max(u8 pc, struct mpam_props *cprops) +{ + u32 val = pc; + + val <<= cprops->bwa_wd; + val = DIV_ROUND_CLOSEST(val, MAX_MBA_BW); + val = max(val, 1) - 1; + val <<= 16 - cprops->bwa_wd; + + return val; +} + +static u32 get_mba_min(struct mpam_props *cprops) +{ + if (!mba_class_use_mbw_max(cprops)) { + WARN_ON_ONCE(1); + return 0; + } + + return mbw_max_to_percent(0, cprops); +} + +/* Find the L3 cache that has affinity with this CPU */ +static int find_l3_equivalent_bitmask(int cpu, cpumask_var_t tmp_cpumask) +{ + u32 cache_id = get_cpu_cacheinfo_id(cpu, 3); + + lockdep_assert_cpus_held(); + + return mpam_get_cpumask_from_cache_id(cache_id, 3, tmp_cpumask); +} + +/* + * topology_matches_l3() - Is the provided class the same shape as L3 + * @victim: The class we'd like to pretend is L3. + * + * resctrl expects all the world's a Xeon, and all counters are on the + * L3. We allow some mapping counters on other classes. This requires + * that the CPU->domain mapping is the same kind of shape. + * + * Using cacheinfo directly would make this work even if resctrl can't + * use the L3 - but cacheinfo can't tell us anything about offline CPUs. + * Using the L3 resctrl domain list also depends on CPUs being online. + * Using the mpam_class we picked for L3 so we can use its domain list + * assumes that there are MPAM controls on the L3. + * Instead, this path eventually uses the mpam_get_cpumask_from_cache_id() + * helper which can tell us about offline CPUs ... but getting the cache_id + * to start with relies on at least one CPU per L3 cache being online at + * boot. + * + * Walk the victim component list and compare the affinity mask with the + * corresponding L3. The topology matches if each victim:component's affinity + * mask is the same as the CPU's corresponding L3's. These lists/masks are + * computed from firmware tables so don't change at runtime. + */ +static bool topology_matches_l3(struct mpam_class *victim) +{ + int cpu, err; + struct mpam_component *victim_iter; + + lockdep_assert_cpus_held(); + + cpumask_var_t __free(free_cpumask_var) tmp_cpumask = CPUMASK_VAR_NULL; + if (!alloc_cpumask_var(&tmp_cpumask, GFP_KERNEL)) + return false; + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(victim_iter, &victim->components, class_list, + srcu_read_lock_held(&mpam_srcu)) { + if (cpumask_empty(&victim_iter->affinity)) { + pr_debug("class %u has CPU-less component %u - can't match L3!\n", + victim->level, victim_iter->comp_id); + return false; + } + + cpu = cpumask_any_and(&victim_iter->affinity, cpu_online_mask); + if (WARN_ON_ONCE(cpu >= nr_cpu_ids)) + return false; + + cpumask_clear(tmp_cpumask); + err = find_l3_equivalent_bitmask(cpu, tmp_cpumask); + if (err) { + pr_debug("Failed to find L3's equivalent component to class %u component %u\n", + victim->level, victim_iter->comp_id); + return false; + } + + /* Any differing bits in the affinity mask? */ + if (!cpumask_equal(tmp_cpumask, &victim_iter->affinity)) { + pr_debug("class %u component %u has Mismatched CPU mask with L3 equivalent\n" + "L3:%*pbl != victim:%*pbl\n", + victim->level, victim_iter->comp_id, + cpumask_pr_args(tmp_cpumask), + cpumask_pr_args(&victim_iter->affinity)); + + return false; + } + } + + return true; +} + +/* + * Test if the traffic for a class matches that at egress from the L3. For + * MSC at memory controllers this is only possible if there is a single L3 + * as otherwise the counters at the memory can include bandwidth from the + * non-local L3. + */ +static bool traffic_matches_l3(struct mpam_class *class) +{ + int err, cpu; + + lockdep_assert_cpus_held(); + + if (class->type == MPAM_CLASS_CACHE && class->level == 3) + return true; + + if (class->type == MPAM_CLASS_CACHE && class->level != 3) { + pr_debug("class %u is a different cache from L3\n", class->level); + return false; + } + + if (class->type != MPAM_CLASS_MEMORY) { + pr_debug("class %u is neither of type cache or memory\n", class->level); + return false; + } + + cpumask_var_t __free(free_cpumask_var) tmp_cpumask = CPUMASK_VAR_NULL; + if (!alloc_cpumask_var(&tmp_cpumask, GFP_KERNEL)) { + pr_debug("cpumask allocation failed\n"); + return false; + } + + cpu = cpumask_any_and(&class->affinity, cpu_online_mask); + err = find_l3_equivalent_bitmask(cpu, tmp_cpumask); + if (err) { + pr_debug("Failed to find L3 downstream to cpu %d\n", cpu); + return false; + } + + if (!cpumask_equal(tmp_cpumask, cpu_possible_mask)) { + pr_debug("There is more than one L3\n"); + return false; + } + + /* Be strict; the traffic might stop in the intermediate cache. */ + if (get_cpu_cacheinfo_id(cpu, 4) != -1) { + pr_debug("L3 isn't the last level of cache\n"); + return false; + } + + if (num_possible_nodes() > 1) { + pr_debug("There is more than one numa node\n"); + return false; + } + +#ifdef CONFIG_HMEM_REPORTING + if (node_devices[cpu_to_node(cpu)]->cache_dev) { + pr_debug("There is a memory side cache\n"); + return false; + } +#endif + + return true; +} + +/* Test whether we can export MPAM_CLASS_CACHE:{2,3}? */ +static void mpam_resctrl_pick_caches(void) +{ + struct mpam_class *class; + struct mpam_resctrl_res *res; + + lockdep_assert_cpus_held(); + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(class, &mpam_classes, classes_list, + srcu_read_lock_held(&mpam_srcu)) { + if (class->type != MPAM_CLASS_CACHE) { + pr_debug("class %u is not a cache\n", class->level); + continue; + } + + if (class->level != 2 && class->level != 3) { + pr_debug("class %u is not L2 or L3\n", class->level); + continue; + } + + if (!cache_has_usable_cpor(class)) { + pr_debug("class %u cache misses CPOR\n", class->level); + continue; + } + + if (!cpumask_equal(&class->affinity, cpu_possible_mask)) { + pr_debug("class %u has missing CPUs, mask %*pb != %*pb\n", class->level, + cpumask_pr_args(&class->affinity), + cpumask_pr_args(cpu_possible_mask)); + continue; + } + + if (class->level == 2) + res = &mpam_resctrl_controls[RDT_RESOURCE_L2]; + else + res = &mpam_resctrl_controls[RDT_RESOURCE_L3]; + res->class = class; + } +} + +static void mpam_resctrl_pick_mba(void) +{ + struct mpam_class *class, *candidate_class = NULL; + struct mpam_resctrl_res *res; + + lockdep_assert_cpus_held(); + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(class, &mpam_classes, classes_list, + srcu_read_lock_held(&mpam_srcu)) { + struct mpam_props *cprops = &class->props; + + if (class->level != 3 && class->type == MPAM_CLASS_CACHE) { + pr_debug("class %u is a cache but not the L3\n", class->level); + continue; + } + + if (!class_has_usable_mba(cprops)) { + pr_debug("class %u has no bandwidth control\n", + class->level); + continue; + } + + if (!cpumask_equal(&class->affinity, cpu_possible_mask)) { + pr_debug("class %u has missing CPUs\n", class->level); + continue; + } + + if (!topology_matches_l3(class)) { + pr_debug("class %u topology doesn't match L3\n", + class->level); + continue; + } + + if (!traffic_matches_l3(class)) { + pr_debug("class %u traffic doesn't match L3 egress\n", + class->level); + continue; + } + + /* + * Pick a resource to be MBA that as close as possible to + * the L3. mbm_total counts the bandwidth leaving the L3 + * cache and MBA should correspond as closely as possible + * for proper operation of mba_sc. + */ + if (!candidate_class || class->level < candidate_class->level) + candidate_class = class; + } + + if (candidate_class) { + pr_debug("selected class %u to back MBA\n", + candidate_class->level); + res = &mpam_resctrl_controls[RDT_RESOURCE_MBA]; + res->class = candidate_class; + } +} + +static void counter_update_class(enum resctrl_event_id evt_id, + struct mpam_class *class) +{ + struct mpam_class *existing_class = mpam_resctrl_counters[evt_id].class; + + if (existing_class) { + if (class->level == 3) { + pr_debug("Existing class is L3 - L3 wins\n"); + return; + } + + if (existing_class->level < class->level) { + pr_debug("Existing class is closer to L3, %u versus %u - closer is better\n", + existing_class->level, class->level); + return; + } + } + + mpam_resctrl_counters[evt_id].class = class; +} + +static void mpam_resctrl_pick_counters(void) +{ + struct mpam_class *class; + + lockdep_assert_cpus_held(); + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(class, &mpam_classes, classes_list, + srcu_read_lock_held(&mpam_srcu)) { + /* The name of the resource is L3... */ + if (class->type == MPAM_CLASS_CACHE && class->level != 3) { + pr_debug("class %u is a cache but not the L3", class->level); + continue; + } + + if (!cpumask_equal(&class->affinity, cpu_possible_mask)) { + pr_debug("class %u does not cover all CPUs", + class->level); + continue; + } + + if (cache_has_usable_csu(class)) { + pr_debug("class %u has usable CSU", + class->level); + + /* CSU counters only make sense on a cache. */ + switch (class->type) { + case MPAM_CLASS_CACHE: + if (update_rmid_limits(class)) + break; + + counter_update_class(QOS_L3_OCCUP_EVENT_ID, class); + break; + default: + break; + } + } + } +} + +static int mpam_resctrl_control_init(struct mpam_resctrl_res *res) +{ + struct mpam_class *class = res->class; + struct mpam_props *cprops = &class->props; + struct rdt_resource *r = &res->resctrl_res; + + switch (r->rid) { + case RDT_RESOURCE_L2: + case RDT_RESOURCE_L3: + r->schema_fmt = RESCTRL_SCHEMA_BITMAP; + r->cache.arch_has_sparse_bitmasks = true; + + r->cache.cbm_len = class->props.cpbm_wd; + /* mpam_devices will reject empty bitmaps */ + r->cache.min_cbm_bits = 1; + + if (r->rid == RDT_RESOURCE_L2) { + r->name = "L2"; + r->ctrl_scope = RESCTRL_L2_CACHE; + r->cdp_capable = true; + } else { + r->name = "L3"; + r->ctrl_scope = RESCTRL_L3_CACHE; + r->cdp_capable = true; + } + + /* + * Which bits are shared with other ...things... Unknown + * devices use partid-0 which uses all the bitmap fields. Until + * we have configured the SMMU and GIC not to do this 'all the + * bits' is the correct answer here. + */ + r->cache.shareable_bits = resctrl_get_default_ctrl(r); + r->alloc_capable = true; + break; + case RDT_RESOURCE_MBA: + r->schema_fmt = RESCTRL_SCHEMA_RANGE; + r->ctrl_scope = RESCTRL_L3_CACHE; + + r->membw.delay_linear = true; + r->membw.throttle_mode = THREAD_THROTTLE_UNDEFINED; + r->membw.min_bw = get_mba_min(cprops); + r->membw.max_bw = MAX_MBA_BW; + r->membw.bw_gran = get_mba_granularity(cprops); + + r->name = "MB"; + r->alloc_capable = true; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int mpam_resctrl_pick_domain_id(int cpu, struct mpam_component *comp) +{ + struct mpam_class *class = comp->class; + + if (class->type == MPAM_CLASS_CACHE) + return comp->comp_id; + + if (topology_matches_l3(class)) { + /* Use the corresponding L3 component ID as the domain ID */ + int id = get_cpu_cacheinfo_id(cpu, 3); + + /* Implies topology_matches_l3() made a mistake */ + if (WARN_ON_ONCE(id == -1)) + return comp->comp_id; + + return id; + } + + /* Otherwise, expose the ID used by the firmware table code. */ + return comp->comp_id; +} + +static int mpam_resctrl_monitor_init(struct mpam_resctrl_mon *mon, + enum resctrl_event_id type) +{ + struct mpam_resctrl_res *res = &mpam_resctrl_controls[RDT_RESOURCE_L3]; + struct rdt_resource *l3 = &res->resctrl_res; + + lockdep_assert_cpus_held(); + + /* + * There also needs to be an L3 cache present. + * The check just requires any online CPU and it can't go offline as we + * hold the cpu lock. + */ + if (get_cpu_cacheinfo_id(raw_smp_processor_id(), 3) == -1) + return 0; + + /* + * If there are no MPAM resources on L3, force it into existence. + * topology_matches_l3() already ensures this looks like the L3. + * The domain-ids will be fixed up by mpam_resctrl_domain_hdr_init(). + */ + if (!res->class) { + pr_warn_once("Faking L3 MSC to enable counters.\n"); + res->class = mpam_resctrl_counters[type].class; + } + + /* + * Called multiple times!, once per event type that has a + * monitoring class. + * Setting name is necessary on monitor only platforms. + */ + l3->name = "L3"; + l3->mon_scope = RESCTRL_L3_CACHE; + + /* + * num-rmid is the upper bound for the number of monitoring groups that + * can exist simultaneously, including the default monitoring group for + * each control group. Hence, advertise the whole rmid_idx space even + * though each control group has its own pmg/rmid space. Unfortunately, + * this does mean userspace needs to know the architecture to correctly + * interpret this value. + */ + l3->mon.num_rmid = resctrl_arch_system_num_rmid_idx(); + + if (resctrl_enable_mon_event(type, false, 0, NULL)) + l3->mon_capable = true; + + return 0; +} + +u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_ctrl_domain *d, + u32 closid, enum resctrl_conf_type type) +{ + u32 partid; + struct mpam_config *cfg; + struct mpam_props *cprops; + struct mpam_resctrl_res *res; + struct mpam_resctrl_dom *dom; + enum mpam_device_features configured_by; + + lockdep_assert_cpus_held(); + + if (!mpam_is_enabled()) + return resctrl_get_default_ctrl(r); + + res = container_of(r, struct mpam_resctrl_res, resctrl_res); + dom = container_of(d, struct mpam_resctrl_dom, resctrl_ctrl_dom); + cprops = &res->class->props; + + /* + * When CDP is enabled, but the resource doesn't support it, + * the control is cloned across both partids. + * Pick one at random to read: + */ + if (mpam_resctrl_hide_cdp(r->rid)) + type = CDP_DATA; + + partid = resctrl_get_config_index(closid, type); + cfg = &dom->ctrl_comp->cfg[partid]; + + switch (r->rid) { + case RDT_RESOURCE_L2: + case RDT_RESOURCE_L3: + configured_by = mpam_feat_cpor_part; + break; + case RDT_RESOURCE_MBA: + if (mpam_has_feature(mpam_feat_mbw_max, cprops)) { + configured_by = mpam_feat_mbw_max; + break; + } + fallthrough; + default: + return resctrl_get_default_ctrl(r); + } + + if (!r->alloc_capable || partid >= resctrl_arch_get_num_closid(r) || + !mpam_has_feature(configured_by, cfg)) + return resctrl_get_default_ctrl(r); + + switch (configured_by) { + case mpam_feat_cpor_part: + return cfg->cpbm; + case mpam_feat_mbw_max: + return mbw_max_to_percent(cfg->mbw_max, cprops); + default: + return resctrl_get_default_ctrl(r); + } +} + +int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_ctrl_domain *d, + u32 closid, enum resctrl_conf_type t, u32 cfg_val) +{ + int err; + u32 partid; + struct mpam_config cfg; + struct mpam_props *cprops; + struct mpam_resctrl_res *res; + struct mpam_resctrl_dom *dom; + + lockdep_assert_cpus_held(); + lockdep_assert_irqs_enabled(); + + if (!mpam_is_enabled()) + return -EINVAL; + + /* + * No need to check the CPU as mpam_apply_config() doesn't care, and + * resctrl_arch_update_domains() relies on this. + */ + res = container_of(r, struct mpam_resctrl_res, resctrl_res); + dom = container_of(d, struct mpam_resctrl_dom, resctrl_ctrl_dom); + cprops = &res->class->props; + + if (mpam_resctrl_hide_cdp(r->rid)) + t = CDP_DATA; + + partid = resctrl_get_config_index(closid, t); + if (!r->alloc_capable || partid >= resctrl_arch_get_num_closid(r)) { + pr_debug("Not alloc capable or computed PARTID out of range\n"); + return -EINVAL; + } + + /* + * Copy the current config to avoid clearing other resources when the + * same component is exposed multiple times through resctrl. + */ + cfg = dom->ctrl_comp->cfg[partid]; + + switch (r->rid) { + case RDT_RESOURCE_L2: + case RDT_RESOURCE_L3: + cfg.cpbm = cfg_val; + mpam_set_feature(mpam_feat_cpor_part, &cfg); + break; + case RDT_RESOURCE_MBA: + if (mpam_has_feature(mpam_feat_mbw_max, cprops)) { + cfg.mbw_max = percent_to_mbw_max(cfg_val, cprops); + mpam_set_feature(mpam_feat_mbw_max, &cfg); + break; + } + fallthrough; + default: + return -EINVAL; + } + + /* + * When CDP is enabled, but the resource doesn't support it, we need to + * apply the same configuration to the other partid. + */ + if (mpam_resctrl_hide_cdp(r->rid)) { + partid = resctrl_get_config_index(closid, CDP_CODE); + err = mpam_apply_config(dom->ctrl_comp, partid, &cfg); + if (err) + return err; + + partid = resctrl_get_config_index(closid, CDP_DATA); + return mpam_apply_config(dom->ctrl_comp, partid, &cfg); + } + + return mpam_apply_config(dom->ctrl_comp, partid, &cfg); +} + +int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) +{ + int err; + struct rdt_ctrl_domain *d; + + lockdep_assert_cpus_held(); + lockdep_assert_irqs_enabled(); + + if (!mpam_is_enabled()) + return -EINVAL; + + list_for_each_entry_rcu(d, &r->ctrl_domains, hdr.list) { + for (enum resctrl_conf_type t = 0; t < CDP_NUM_TYPES; t++) { + struct resctrl_staged_config *cfg = &d->staged_config[t]; + + if (!cfg->have_new_ctrl) + continue; + + err = resctrl_arch_update_one(r, d, closid, t, + cfg->new_ctrl); + if (err) + return err; + } + } + + return 0; +} + +void resctrl_arch_reset_all_ctrls(struct rdt_resource *r) +{ + struct mpam_resctrl_res *res; + + lockdep_assert_cpus_held(); + + if (!mpam_is_enabled()) + return; + + res = container_of(r, struct mpam_resctrl_res, resctrl_res); + mpam_reset_class_locked(res->class); +} + +static void mpam_resctrl_domain_hdr_init(int cpu, struct mpam_component *comp, + enum resctrl_res_level rid, + struct rdt_domain_hdr *hdr) +{ + lockdep_assert_cpus_held(); + + INIT_LIST_HEAD(&hdr->list); + hdr->id = mpam_resctrl_pick_domain_id(cpu, comp); + hdr->rid = rid; + cpumask_set_cpu(cpu, &hdr->cpu_mask); +} + +static void mpam_resctrl_online_domain_hdr(unsigned int cpu, + struct rdt_domain_hdr *hdr) +{ + lockdep_assert_cpus_held(); + + cpumask_set_cpu(cpu, &hdr->cpu_mask); +} + +/** + * mpam_resctrl_offline_domain_hdr() - Update the domain header to remove a CPU. + * @cpu: The CPU to remove from the domain. + * @hdr: The domain's header. + * + * Removes @cpu from the header mask. If this was the last CPU in the domain, + * the domain header is removed from its parent list and true is returned, + * indicating the parent structure can be freed. + * If there are other CPUs in the domain, returns false. + */ +static bool mpam_resctrl_offline_domain_hdr(unsigned int cpu, + struct rdt_domain_hdr *hdr) +{ + lockdep_assert_held(&domain_list_lock); + + cpumask_clear_cpu(cpu, &hdr->cpu_mask); + if (cpumask_empty(&hdr->cpu_mask)) { + list_del_rcu(&hdr->list); + synchronize_rcu(); + return true; + } + + return false; +} + +static void mpam_resctrl_domain_insert(struct list_head *list, + struct rdt_domain_hdr *new) +{ + struct rdt_domain_hdr *err; + struct list_head *pos = NULL; + + lockdep_assert_held(&domain_list_lock); + + err = resctrl_find_domain(list, new->id, &pos); + if (WARN_ON_ONCE(err)) + return; + + list_add_tail_rcu(&new->list, pos); +} + +static struct mpam_component *find_component(struct mpam_class *class, int cpu) +{ + struct mpam_component *comp; + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(comp, &class->components, class_list, + srcu_read_lock_held(&mpam_srcu)) { + if (cpumask_test_cpu(cpu, &comp->affinity)) + return comp; + } + + return NULL; +} + +static struct mpam_resctrl_dom * +mpam_resctrl_alloc_domain(unsigned int cpu, struct mpam_resctrl_res *res) +{ + int err; + struct mpam_resctrl_dom *dom; + struct rdt_l3_mon_domain *mon_d; + struct rdt_ctrl_domain *ctrl_d; + struct mpam_class *class = res->class; + struct mpam_component *comp_iter, *ctrl_comp; + struct rdt_resource *r = &res->resctrl_res; + + lockdep_assert_held(&domain_list_lock); + + ctrl_comp = NULL; + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(comp_iter, &class->components, class_list, + srcu_read_lock_held(&mpam_srcu)) { + if (cpumask_test_cpu(cpu, &comp_iter->affinity)) { + ctrl_comp = comp_iter; + break; + } + } + + /* class has no component for this CPU */ + if (WARN_ON_ONCE(!ctrl_comp)) + return ERR_PTR(-EINVAL); + + dom = kzalloc_node(sizeof(*dom), GFP_KERNEL, cpu_to_node(cpu)); + if (!dom) + return ERR_PTR(-ENOMEM); + + if (r->alloc_capable) { + dom->ctrl_comp = ctrl_comp; + + ctrl_d = &dom->resctrl_ctrl_dom; + mpam_resctrl_domain_hdr_init(cpu, ctrl_comp, r->rid, &ctrl_d->hdr); + ctrl_d->hdr.type = RESCTRL_CTRL_DOMAIN; + err = resctrl_online_ctrl_domain(r, ctrl_d); + if (err) + goto free_domain; + + mpam_resctrl_domain_insert(&r->ctrl_domains, &ctrl_d->hdr); + } else { + pr_debug("Skipped control domain online - no controls\n"); + } + + if (r->mon_capable) { + struct mpam_component *any_mon_comp = NULL; + struct mpam_resctrl_mon *mon; + enum resctrl_event_id eventid; + + /* + * Even if the monitor domain is backed by a different + * component, the L3 component IDs need to be used... only + * there may be no ctrl_comp for the L3. + * Search each event's class list for a component with + * overlapping CPUs and set up the dom->mon_comp array. + */ + + for_each_mpam_resctrl_mon(mon, eventid) { + struct mpam_component *mon_comp; + + if (!mon->class) + continue; // dummy resource + + mon_comp = find_component(mon->class, cpu); + dom->mon_comp[eventid] = mon_comp; + if (mon_comp) + any_mon_comp = mon_comp; + } + if (!any_mon_comp) { + WARN_ON_ONCE(0); + err = -EFAULT; + goto offline_ctrl_domain; + } + + mon_d = &dom->resctrl_mon_dom; + mpam_resctrl_domain_hdr_init(cpu, any_mon_comp, r->rid, &mon_d->hdr); + mon_d->hdr.type = RESCTRL_MON_DOMAIN; + err = resctrl_online_mon_domain(r, &mon_d->hdr); + if (err) + goto offline_ctrl_domain; + + mpam_resctrl_domain_insert(&r->mon_domains, &mon_d->hdr); + } else { + pr_debug("Skipped monitor domain online - no monitors\n"); + } + + return dom; + +offline_ctrl_domain: + if (r->alloc_capable) { + mpam_resctrl_offline_domain_hdr(cpu, &ctrl_d->hdr); + resctrl_offline_ctrl_domain(r, ctrl_d); + } +free_domain: + kfree(dom); + dom = ERR_PTR(err); + + return dom; +} + +/* + * We know all the monitors are associated with the L3, even if there are no + * controls and therefore no control component. Find the cache-id for the CPU + * and use that to search for existing resctrl domains. + * This relies on mpam_resctrl_pick_domain_id() using the L3 cache-id + * for anything that is not a cache. + */ +static struct mpam_resctrl_dom *mpam_resctrl_get_mon_domain_from_cpu(int cpu) +{ + int cache_id; + struct mpam_resctrl_dom *dom; + struct mpam_resctrl_res *l3 = &mpam_resctrl_controls[RDT_RESOURCE_L3]; + + lockdep_assert_cpus_held(); + + if (!l3->class) + return NULL; + cache_id = get_cpu_cacheinfo_id(cpu, 3); + if (cache_id < 0) + return NULL; + + list_for_each_entry_rcu(dom, &l3->resctrl_res.mon_domains, resctrl_mon_dom.hdr.list) { + if (dom->resctrl_mon_dom.hdr.id == cache_id) + return dom; + } + + return NULL; +} + +static struct mpam_resctrl_dom * +mpam_resctrl_get_domain_from_cpu(int cpu, struct mpam_resctrl_res *res) +{ + struct mpam_resctrl_dom *dom; + struct rdt_resource *r = &res->resctrl_res; + + lockdep_assert_cpus_held(); + + list_for_each_entry_rcu(dom, &r->ctrl_domains, resctrl_ctrl_dom.hdr.list) { + if (cpumask_test_cpu(cpu, &dom->ctrl_comp->affinity)) + return dom; + } + + if (r->rid != RDT_RESOURCE_L3) + return NULL; + + /* Search the mon domain list too - needed on monitor only platforms. */ + return mpam_resctrl_get_mon_domain_from_cpu(cpu); +} + +int mpam_resctrl_online_cpu(unsigned int cpu) +{ + struct mpam_resctrl_res *res; + enum resctrl_res_level rid; + + guard(mutex)(&domain_list_lock); + for_each_mpam_resctrl_control(res, rid) { + struct mpam_resctrl_dom *dom; + struct rdt_resource *r = &res->resctrl_res; + + if (!res->class) + continue; // dummy_resource; + + dom = mpam_resctrl_get_domain_from_cpu(cpu, res); + if (!dom) { + dom = mpam_resctrl_alloc_domain(cpu, res); + if (IS_ERR(dom)) + return PTR_ERR(dom); + } else { + if (r->alloc_capable) { + struct rdt_ctrl_domain *ctrl_d = &dom->resctrl_ctrl_dom; + + mpam_resctrl_online_domain_hdr(cpu, &ctrl_d->hdr); + } + if (r->mon_capable) { + struct rdt_l3_mon_domain *mon_d = &dom->resctrl_mon_dom; + + mpam_resctrl_online_domain_hdr(cpu, &mon_d->hdr); + } + } + } + + resctrl_online_cpu(cpu); + + return 0; +} + +void mpam_resctrl_offline_cpu(unsigned int cpu) +{ + struct mpam_resctrl_res *res; + enum resctrl_res_level rid; + + resctrl_offline_cpu(cpu); + + guard(mutex)(&domain_list_lock); + for_each_mpam_resctrl_control(res, rid) { + struct mpam_resctrl_dom *dom; + struct rdt_l3_mon_domain *mon_d; + struct rdt_ctrl_domain *ctrl_d; + bool ctrl_dom_empty, mon_dom_empty; + struct rdt_resource *r = &res->resctrl_res; + + if (!res->class) + continue; // dummy resource + + dom = mpam_resctrl_get_domain_from_cpu(cpu, res); + if (WARN_ON_ONCE(!dom)) + continue; + + if (r->alloc_capable) { + ctrl_d = &dom->resctrl_ctrl_dom; + ctrl_dom_empty = mpam_resctrl_offline_domain_hdr(cpu, &ctrl_d->hdr); + if (ctrl_dom_empty) + resctrl_offline_ctrl_domain(&res->resctrl_res, ctrl_d); + } else { + ctrl_dom_empty = true; + } + + if (r->mon_capable) { + mon_d = &dom->resctrl_mon_dom; + mon_dom_empty = mpam_resctrl_offline_domain_hdr(cpu, &mon_d->hdr); + if (mon_dom_empty) + resctrl_offline_mon_domain(&res->resctrl_res, &mon_d->hdr); + } else { + mon_dom_empty = true; + } + + if (ctrl_dom_empty && mon_dom_empty) + kfree(dom); + } +} + +int mpam_resctrl_setup(void) +{ + int err = 0; + struct mpam_resctrl_res *res; + enum resctrl_res_level rid; + struct mpam_resctrl_mon *mon; + enum resctrl_event_id eventid; + + wait_event(wait_cacheinfo_ready, cacheinfo_ready); + + cpus_read_lock(); + for_each_mpam_resctrl_control(res, rid) { + INIT_LIST_HEAD_RCU(&res->resctrl_res.ctrl_domains); + INIT_LIST_HEAD_RCU(&res->resctrl_res.mon_domains); + res->resctrl_res.rid = rid; + } + + /* Find some classes to use for controls */ + mpam_resctrl_pick_caches(); + mpam_resctrl_pick_mba(); + + /* Initialise the resctrl structures from the classes */ + for_each_mpam_resctrl_control(res, rid) { + if (!res->class) + continue; // dummy resource + + err = mpam_resctrl_control_init(res); + if (err) { + pr_debug("Failed to initialise rid %u\n", rid); + goto internal_error; + } + } + + /* Find some classes to use for monitors */ + mpam_resctrl_pick_counters(); + + for_each_mpam_resctrl_mon(mon, eventid) { + if (!mon->class) + continue; // dummy resource + + err = mpam_resctrl_monitor_init(mon, eventid); + if (err) { + pr_debug("Failed to initialise event %u\n", eventid); + goto internal_error; + } + } + + cpus_read_unlock(); + + if (!resctrl_arch_alloc_capable() && !resctrl_arch_mon_capable()) { + pr_debug("No alloc(%u) or monitor(%u) found - resctrl not supported\n", + resctrl_arch_alloc_capable(), resctrl_arch_mon_capable()); + return -EOPNOTSUPP; + } + + err = resctrl_init(); + if (err) + return err; + + WRITE_ONCE(resctrl_enabled, true); + + return 0; + +internal_error: + cpus_read_unlock(); + pr_debug("Internal error %d - resctrl not supported\n", err); + return err; +} + +void mpam_resctrl_exit(void) +{ + if (!READ_ONCE(resctrl_enabled)) + return; + + WRITE_ONCE(resctrl_enabled, false); + resctrl_exit(); +} + +/* + * The driver is detaching an MSC from this class, if resctrl was using it, + * pull on resctrl_exit(). + */ +void mpam_resctrl_teardown_class(struct mpam_class *class) +{ + struct mpam_resctrl_res *res; + enum resctrl_res_level rid; + struct mpam_resctrl_mon *mon; + enum resctrl_event_id eventid; + + might_sleep(); + + for_each_mpam_resctrl_control(res, rid) { + if (res->class == class) { + res->class = NULL; + break; + } + } + for_each_mpam_resctrl_mon(mon, eventid) { + if (mon->class == class) { + mon->class = NULL; + break; + } + } +} + +static int __init __cacheinfo_ready(void) +{ + cacheinfo_ready = true; + wake_up(&wait_cacheinfo_ready); + + return 0; +} +device_initcall_sync(__cacheinfo_ready); + +#ifdef CONFIG_MPAM_KUNIT_TEST +#include "test_mpam_resctrl.c" +#endif diff --git a/drivers/resctrl/test_mpam_resctrl.c b/drivers/resctrl/test_mpam_resctrl.c new file mode 100644 index 000000000000..b93d6ad87e43 --- /dev/null +++ b/drivers/resctrl/test_mpam_resctrl.c @@ -0,0 +1,315 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2025 Arm Ltd. +/* This file is intended to be included into mpam_resctrl.c */ + +#include <kunit/test.h> +#include <linux/array_size.h> +#include <linux/bits.h> +#include <linux/math.h> +#include <linux/sprintf.h> + +struct percent_value_case { + u8 pc; + u8 width; + u16 value; +}; + +/* + * Mysterious inscriptions taken from the union of ARM DDI 0598D.b, + * "Arm Architecture Reference Manual Supplement - Memory System + * Resource Partitioning and Monitoring (MPAM), for A-profile + * architecture", Section 9.8, "About the fixed-point fractional + * format" (exact percentage entries only) and ARM IHI0099B.a + * "MPAM system component specification", Section 9.3, + * "The fixed-point fractional format": + */ +static const struct percent_value_case percent_value_cases[] = { + /* Architectural cases: */ + { 1, 8, 1 }, { 1, 12, 0x27 }, { 1, 16, 0x28e }, + { 25, 8, 0x3f }, { 25, 12, 0x3ff }, { 25, 16, 0x3fff }, + { 33, 8, 0x53 }, { 33, 12, 0x546 }, { 33, 16, 0x5479 }, + { 35, 8, 0x58 }, { 35, 12, 0x598 }, { 35, 16, 0x5998 }, + { 45, 8, 0x72 }, { 45, 12, 0x732 }, { 45, 16, 0x7332 }, + { 50, 8, 0x7f }, { 50, 12, 0x7ff }, { 50, 16, 0x7fff }, + { 52, 8, 0x84 }, { 52, 12, 0x850 }, { 52, 16, 0x851d }, + { 55, 8, 0x8b }, { 55, 12, 0x8cb }, { 55, 16, 0x8ccb }, + { 58, 8, 0x93 }, { 58, 12, 0x946 }, { 58, 16, 0x9479 }, + { 75, 8, 0xbf }, { 75, 12, 0xbff }, { 75, 16, 0xbfff }, + { 80, 8, 0xcb }, { 80, 12, 0xccb }, { 80, 16, 0xcccb }, + { 88, 8, 0xe0 }, { 88, 12, 0xe13 }, { 88, 16, 0xe146 }, + { 95, 8, 0xf2 }, { 95, 12, 0xf32 }, { 95, 16, 0xf332 }, + { 100, 8, 0xff }, { 100, 12, 0xfff }, { 100, 16, 0xffff }, +}; + +static void test_percent_value_desc(const struct percent_value_case *param, + char *desc) +{ + snprintf(desc, KUNIT_PARAM_DESC_SIZE, + "pc=%d, width=%d, value=0x%.*x\n", + param->pc, param->width, + DIV_ROUND_UP(param->width, 4), param->value); +} + +KUNIT_ARRAY_PARAM(test_percent_value, percent_value_cases, + test_percent_value_desc); + +struct percent_value_test_info { + u32 pc; /* result of value-to-percent conversion */ + u32 value; /* result of percent-to-value conversion */ + u32 max_value; /* maximum raw value allowed by test params */ + unsigned int shift; /* promotes raw testcase value to 16 bits */ +}; + +/* + * Convert a reference percentage to a fixed-point MAX value and + * vice-versa, based on param (not test->param_value!) + */ +static void __prepare_percent_value_test(struct kunit *test, + struct percent_value_test_info *res, + const struct percent_value_case *param) +{ + struct mpam_props fake_props = { }; + + /* Reject bogus test parameters that would break the tests: */ + KUNIT_ASSERT_GE(test, param->width, 1); + KUNIT_ASSERT_LE(test, param->width, 16); + KUNIT_ASSERT_LT(test, param->value, 1 << param->width); + + mpam_set_feature(mpam_feat_mbw_max, &fake_props); + fake_props.bwa_wd = param->width; + + res->shift = 16 - param->width; + res->max_value = GENMASK_U32(param->width - 1, 0); + res->value = percent_to_mbw_max(param->pc, &fake_props); + res->pc = mbw_max_to_percent(param->value << res->shift, &fake_props); +} + +static void test_get_mba_granularity(struct kunit *test) +{ + int ret; + struct mpam_props fake_props = { }; + + /* Use MBW_MAX */ + mpam_set_feature(mpam_feat_mbw_max, &fake_props); + + fake_props.bwa_wd = 0; + KUNIT_EXPECT_FALSE(test, mba_class_use_mbw_max(&fake_props)); + + fake_props.bwa_wd = 1; + KUNIT_EXPECT_TRUE(test, mba_class_use_mbw_max(&fake_props)); + + /* Architectural maximum: */ + fake_props.bwa_wd = 16; + KUNIT_EXPECT_TRUE(test, mba_class_use_mbw_max(&fake_props)); + + /* No usable control... */ + fake_props.bwa_wd = 0; + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 0); + + fake_props.bwa_wd = 1; + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 50); /* DIV_ROUND_UP(100, 1 << 1)% = 50% */ + + fake_props.bwa_wd = 2; + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 25); /* DIV_ROUND_UP(100, 1 << 2)% = 25% */ + + fake_props.bwa_wd = 3; + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 13); /* DIV_ROUND_UP(100, 1 << 3)% = 13% */ + + fake_props.bwa_wd = 6; + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 2); /* DIV_ROUND_UP(100, 1 << 6)% = 2% */ + + fake_props.bwa_wd = 7; + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 1); /* DIV_ROUND_UP(100, 1 << 7)% = 1% */ + + /* Granularity saturates at 1% */ + fake_props.bwa_wd = 16; /* architectural maximum */ + ret = get_mba_granularity(&fake_props); + KUNIT_EXPECT_EQ(test, ret, 1); /* DIV_ROUND_UP(100, 1 << 16)% = 1% */ +} + +static void test_mbw_max_to_percent(struct kunit *test) +{ + const struct percent_value_case *param = test->param_value; + struct percent_value_test_info res; + + /* + * Since the reference values in percent_value_cases[] all + * correspond to exact percentages, round-to-nearest will + * always give the exact percentage back when the MPAM max + * value has precision of 0.5% or finer. (Always true for the + * reference data, since they all specify 8 bits or more of + * precision. + * + * So, keep it simple and demand an exact match: + */ + __prepare_percent_value_test(test, &res, param); + KUNIT_EXPECT_EQ(test, res.pc, param->pc); +} + +static void test_percent_to_mbw_max(struct kunit *test) +{ + const struct percent_value_case *param = test->param_value; + struct percent_value_test_info res; + + __prepare_percent_value_test(test, &res, param); + + KUNIT_EXPECT_GE(test, res.value, param->value << res.shift); + KUNIT_EXPECT_LE(test, res.value, (param->value + 1) << res.shift); + KUNIT_EXPECT_LE(test, res.value, res.max_value << res.shift); + + /* No flexibility allowed for 0% and 100%! */ + + if (param->pc == 0) + KUNIT_EXPECT_EQ(test, res.value, 0); + + if (param->pc == 100) + KUNIT_EXPECT_EQ(test, res.value, res.max_value << res.shift); +} + +static const void *test_all_bwa_wd_gen_params(struct kunit *test, const void *prev, + char *desc) +{ + uintptr_t param = (uintptr_t)prev; + + if (param > 15) + return NULL; + + param++; + + snprintf(desc, KUNIT_PARAM_DESC_SIZE, "wd=%u\n", (unsigned int)param); + + return (void *)param; +} + +static unsigned int test_get_bwa_wd(struct kunit *test) +{ + uintptr_t param = (uintptr_t)test->param_value; + + KUNIT_ASSERT_GE(test, param, 1); + KUNIT_ASSERT_LE(test, param, 16); + + return param; +} + +static void test_mbw_max_to_percent_limits(struct kunit *test) +{ + struct mpam_props fake_props = {0}; + u32 max_value; + + mpam_set_feature(mpam_feat_mbw_max, &fake_props); + fake_props.bwa_wd = test_get_bwa_wd(test); + max_value = GENMASK(15, 16 - fake_props.bwa_wd); + + KUNIT_EXPECT_EQ(test, mbw_max_to_percent(max_value, &fake_props), + MAX_MBA_BW); + KUNIT_EXPECT_EQ(test, mbw_max_to_percent(0, &fake_props), + get_mba_min(&fake_props)); + + /* + * Rounding policy dependent 0% sanity-check: + * With round-to-nearest, the minimum mbw_max value really + * should map to 0% if there are at least 200 steps. + * (100 steps may be enough for some other rounding policies.) + */ + if (fake_props.bwa_wd >= 8) + KUNIT_EXPECT_EQ(test, mbw_max_to_percent(0, &fake_props), 0); + + if (fake_props.bwa_wd < 8 && + mbw_max_to_percent(0, &fake_props) == 0) + kunit_warn(test, "wd=%d: Testsuite/driver Rounding policy mismatch?", + fake_props.bwa_wd); +} + +/* + * Check that converting a percentage to mbw_max and back again (or, as + * appropriate, vice-versa) always restores the original value: + */ +static void test_percent_max_roundtrip_stability(struct kunit *test) +{ + struct mpam_props fake_props = {0}; + unsigned int shift; + u32 pc, max, pc2, max2; + + mpam_set_feature(mpam_feat_mbw_max, &fake_props); + fake_props.bwa_wd = test_get_bwa_wd(test); + shift = 16 - fake_props.bwa_wd; + + /* + * Converting a valid value from the coarser scale to the finer + * scale and back again must yield the original value: + */ + if (fake_props.bwa_wd >= 7) { + /* More than 100 steps: only test exact pc values: */ + for (pc = get_mba_min(&fake_props); pc <= MAX_MBA_BW; pc++) { + max = percent_to_mbw_max(pc, &fake_props); + pc2 = mbw_max_to_percent(max, &fake_props); + KUNIT_EXPECT_EQ(test, pc2, pc); + } + } else { + /* Fewer than 100 steps: only test exact mbw_max values: */ + for (max = 0; max < 1 << 16; max += 1 << shift) { + pc = mbw_max_to_percent(max, &fake_props); + max2 = percent_to_mbw_max(pc, &fake_props); + KUNIT_EXPECT_EQ(test, max2, max); + } + } +} + +static void test_percent_to_max_rounding(struct kunit *test) +{ + const struct percent_value_case *param = test->param_value; + unsigned int num_rounded_up = 0, total = 0; + struct percent_value_test_info res; + + for (param = percent_value_cases, total = 0; + param < &percent_value_cases[ARRAY_SIZE(percent_value_cases)]; + param++, total++) { + __prepare_percent_value_test(test, &res, param); + if (res.value > param->value << res.shift) + num_rounded_up++; + } + + /* + * The MPAM driver applies a round-to-nearest policy, whereas a + * round-down policy seems to have been applied in the + * reference table from which the test vectors were selected. + * + * For a large and well-distributed suite of test vectors, + * about half should be rounded up and half down compared with + * the reference table. The actual test vectors are few in + * number and probably not very well distributed however, so + * tolerate a round-up rate of between 1/4 and 3/4 before + * crying foul: + */ + + kunit_info(test, "Round-up rate: %u%% (%u/%u)\n", + DIV_ROUND_CLOSEST(num_rounded_up * 100, total), + num_rounded_up, total); + + KUNIT_EXPECT_GE(test, 4 * num_rounded_up, 1 * total); + KUNIT_EXPECT_LE(test, 4 * num_rounded_up, 3 * total); +} + +static struct kunit_case mpam_resctrl_test_cases[] = { + KUNIT_CASE(test_get_mba_granularity), + KUNIT_CASE_PARAM(test_mbw_max_to_percent, test_percent_value_gen_params), + KUNIT_CASE_PARAM(test_percent_to_mbw_max, test_percent_value_gen_params), + KUNIT_CASE_PARAM(test_mbw_max_to_percent_limits, test_all_bwa_wd_gen_params), + KUNIT_CASE(test_percent_to_max_rounding), + KUNIT_CASE_PARAM(test_percent_max_roundtrip_stability, + test_all_bwa_wd_gen_params), + {} +}; + +static struct kunit_suite mpam_resctrl_test_suite = { + .name = "mpam_resctrl_test_suite", + .test_cases = mpam_resctrl_test_cases, +}; + +kunit_test_suites(&mpam_resctrl_test_suite); |