diff options
Diffstat (limited to 'arch/x86/kernel/cpu')
| -rw-r--r-- | arch/x86/kernel/cpu/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_cacheinfo.c | 20 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt.c | 403 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 1115 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt_schemata.c | 245 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/scattered.c | 11 |
6 files changed, 1792 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index 33b63670bf09..52000010c62e 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -32,6 +32,8 @@ obj-$(CONFIG_CPU_SUP_CENTAUR) += centaur.o obj-$(CONFIG_CPU_SUP_TRANSMETA_32) += transmeta.o obj-$(CONFIG_CPU_SUP_UMC_32) += umc.o +obj-$(CONFIG_INTEL_RDT_A) += intel_rdt.o intel_rdt_rdtgroup.o intel_rdt_schemata.o + obj-$(CONFIG_X86_MCE) += mcheck/ obj-$(CONFIG_MTRR) += mtrr/ obj-$(CONFIG_MICROCODE) += microcode/ diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c index be6337156502..0282b0df004a 100644 --- a/arch/x86/kernel/cpu/intel_cacheinfo.c +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c @@ -153,6 +153,7 @@ struct _cpuid4_info_regs { union _cpuid4_leaf_eax eax; union _cpuid4_leaf_ebx ebx; union _cpuid4_leaf_ecx ecx; + unsigned int id; unsigned long size; struct amd_northbridge *nb; }; @@ -894,6 +895,8 @@ static void __cache_cpumap_setup(unsigned int cpu, int index, static void ci_leaf_init(struct cacheinfo *this_leaf, struct _cpuid4_info_regs *base) { + this_leaf->id = base->id; + this_leaf->attributes = CACHE_ID; this_leaf->level = base->eax.split.level; this_leaf->type = cache_type_map[base->eax.split.type]; this_leaf->coherency_line_size = @@ -920,6 +923,22 @@ static int __init_cache_level(unsigned int cpu) return 0; } +/* + * The max shared threads number comes from CPUID.4:EAX[25-14] with input + * ECX as cache index. Then right shift apicid by the number's order to get + * cache id for this cache node. + */ +static void get_cache_id(int cpu, struct _cpuid4_info_regs *id4_regs) +{ + struct cpuinfo_x86 *c = &cpu_data(cpu); + unsigned long num_threads_sharing; + int index_msb; + + num_threads_sharing = 1 + id4_regs->eax.split.num_threads_sharing; + index_msb = get_count_order(num_threads_sharing); + id4_regs->id = c->apicid >> index_msb; +} + static int __populate_cache_leaves(unsigned int cpu) { unsigned int idx, ret; @@ -931,6 +950,7 @@ static int __populate_cache_leaves(unsigned int cpu) ret = cpuid4_cache_lookup_regs(idx, &id4_regs); if (ret) return ret; + get_cache_id(cpu, &id4_regs); ci_leaf_init(this_leaf++, &id4_regs); __cache_cpumap_setup(cpu, idx, &id4_regs); } diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c new file mode 100644 index 000000000000..5a533fefefa0 --- /dev/null +++ b/arch/x86/kernel/cpu/intel_rdt.c @@ -0,0 +1,403 @@ +/* + * Resource Director Technology(RDT) + * - Cache Allocation code. + * + * Copyright (C) 2016 Intel Corporation + * + * Authors: + * Fenghua Yu <fenghua.yu@intel.com> + * Tony Luck <tony.luck@intel.com> + * Vikas Shivappa <vikas.shivappa@intel.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * More information about RDT be found in the Intel (R) x86 Architecture + * Software Developer Manual June 2016, volume 3, section 17.17. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/cacheinfo.h> +#include <linux/cpuhotplug.h> + +#include <asm/intel-family.h> +#include <asm/intel_rdt.h> + +/* Mutex to protect rdtgroup access. */ +DEFINE_MUTEX(rdtgroup_mutex); + +DEFINE_PER_CPU_READ_MOSTLY(int, cpu_closid); + +#define domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].domains) + +struct rdt_resource rdt_resources_all[] = { + { + .name = "L3", + .domains = domain_init(RDT_RESOURCE_L3), + .msr_base = IA32_L3_CBM_BASE, + .min_cbm_bits = 1, + .cache_level = 3, + .cbm_idx_multi = 1, + .cbm_idx_offset = 0 + }, + { + .name = "L3DATA", + .domains = domain_init(RDT_RESOURCE_L3DATA), + .msr_base = IA32_L3_CBM_BASE, + .min_cbm_bits = 1, + .cache_level = 3, + .cbm_idx_multi = 2, + .cbm_idx_offset = 0 + }, + { + .name = "L3CODE", + .domains = domain_init(RDT_RESOURCE_L3CODE), + .msr_base = IA32_L3_CBM_BASE, + .min_cbm_bits = 1, + .cache_level = 3, + .cbm_idx_multi = 2, + .cbm_idx_offset = 1 + }, + { + .name = "L2", + .domains = domain_init(RDT_RESOURCE_L2), + .msr_base = IA32_L2_CBM_BASE, + .min_cbm_bits = 1, + .cache_level = 2, + .cbm_idx_multi = 1, + .cbm_idx_offset = 0 + }, +}; + +static int cbm_idx(struct rdt_resource *r, int closid) +{ + return closid * r->cbm_idx_multi + r->cbm_idx_offset; +} + +/* + * cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs + * as they do not have CPUID enumeration support for Cache allocation. + * The check for Vendor/Family/Model is not enough to guarantee that + * the MSRs won't #GP fault because only the following SKUs support + * CAT: + * Intel(R) Xeon(R) CPU E5-2658 v3 @ 2.20GHz + * Intel(R) Xeon(R) CPU E5-2648L v3 @ 1.80GHz + * Intel(R) Xeon(R) CPU E5-2628L v3 @ 2.00GHz + * Intel(R) Xeon(R) CPU E5-2618L v3 @ 2.30GHz + * Intel(R) Xeon(R) CPU E5-2608L v3 @ 2.00GHz + * Intel(R) Xeon(R) CPU E5-2658A v3 @ 2.20GHz + * + * Probe by trying to write the first of the L3 cach mask registers + * and checking that the bits stick. Max CLOSids is always 4 and max cbm length + * is always 20 on hsw server parts. The minimum cache bitmask length + * allowed for HSW server is always 2 bits. Hardcode all of them. + */ +static inline bool cache_alloc_hsw_probe(void) +{ + if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && + boot_cpu_data.x86 == 6 && + boot_cpu_data.x86_model == INTEL_FAM6_HASWELL_X) { + struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3]; + u32 l, h, max_cbm = BIT_MASK(20) - 1; + + if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0)) + return false; + rdmsr(IA32_L3_CBM_BASE, l, h); + + /* If all the bits were set in MSR, return success */ + if (l != max_cbm) + return false; + + r->num_closid = 4; + r->cbm_len = 20; + r->max_cbm = max_cbm; + r->min_cbm_bits = 2; + r->capable = true; + r->enabled = true; + + return true; + } + + return false; +} + +static void rdt_get_config(int idx, struct rdt_resource *r) +{ + union cpuid_0x10_1_eax eax; + union cpuid_0x10_1_edx edx; + u32 ebx, ecx; + + cpuid_count(0x00000010, idx, &eax.full, &ebx, &ecx, &edx.full); + r->num_closid = edx.split.cos_max + 1; + r->cbm_len = eax.split.cbm_len + 1; + r->max_cbm = BIT_MASK(eax.split.cbm_len + 1) - 1; + r->capable = true; + r->enabled = true; +} + +static void rdt_get_cdp_l3_config(int type) +{ + struct rdt_resource *r_l3 = &rdt_resources_all[RDT_RESOURCE_L3]; + struct rdt_resource *r = &rdt_resources_all[type]; + + r->num_closid = r_l3->num_closid / 2; + r->cbm_len = r_l3->cbm_len; + r->max_cbm = r_l3->max_cbm; + r->capable = true; + /* + * By default, CDP is disabled. CDP can be enabled by mount parameter + * "cdp" during resctrl file system mount time. + */ + r->enabled = false; +} + +static inline bool get_rdt_resources(void) +{ + bool ret = false; + + if (cache_alloc_hsw_probe()) + return true; + + if (!boot_cpu_has(X86_FEATURE_RDT_A)) + return false; + + if (boot_cpu_has(X86_FEATURE_CAT_L3)) { + rdt_get_config(1, &rdt_resources_all[RDT_RESOURCE_L3]); + if (boot_cpu_has(X86_FEATURE_CDP_L3)) { + rdt_get_cdp_l3_config(RDT_RESOURCE_L3DATA); + rdt_get_cdp_l3_config(RDT_RESOURCE_L3CODE); + } + ret = true; + } + if (boot_cpu_has(X86_FEATURE_CAT_L2)) { + /* CPUID 0x10.2 fields are same format at 0x10.1 */ + rdt_get_config(2, &rdt_resources_all[RDT_RESOURCE_L2]); + ret = true; + } + + return ret; +} + +static int get_cache_id(int cpu, int level) +{ + struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu); + int i; + + for (i = 0; i < ci->num_leaves; i++) { + if (ci->info_list[i].level == level) + return ci->info_list[i].id; + } + + return -1; +} + +void rdt_cbm_update(void *arg) +{ + struct msr_param *m = (struct msr_param *)arg; + struct rdt_resource *r = m->res; + int i, cpu = smp_processor_id(); + struct rdt_domain *d; + + list_for_each_entry(d, &r->domains, list) { + /* Find the domain that contains this CPU */ + if (cpumask_test_cpu(cpu, &d->cpu_mask)) + goto found; + } + pr_info_once("cpu %d not found in any domain for resource %s\n", + cpu, r->name); + + return; + +found: + for (i = m->low; i < m->high; i++) { + int idx = cbm_idx(r, i); + + wrmsrl(r->msr_base + idx, d->cbm[i]); + } +} + +/* + * rdt_find_domain - Find a domain in a resource that matches input resource id + * + * Search resource r's domain list to find the resource id. If the resource + * id is found in a domain, return the domain. Otherwise, if requested by + * caller, return the first domain whose id is bigger than the input id. + * The domain list is sorted by id in ascending order. + */ +static struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id, + struct list_head **pos) +{ + struct rdt_domain *d; + struct list_head *l; + + if (id < 0) + return ERR_PTR(id); + + list_for_each(l, &r->domains) { + d = list_entry(l, struct rdt_domain, list); + /* When id is found, return its domain. */ + if (id == d->id) + return d; + /* Stop searching when finding id's position in sorted list. */ + if (id < d->id) + break; + } + + if (pos) + *pos = l; + + return NULL; +} + +/* + * domain_add_cpu - Add a cpu to a resource's domain list. + * + * If an existing domain in the resource r's domain list matches the cpu's + * resource id, add the cpu in the domain. + * + * Otherwise, a new domain is allocated and inserted into the right position + * in the domain list sorted by id in ascending order. + * + * The order in the domain list is visible to users when we print entries + * in the schemata file and schemata input is validated to have the same order + * as this list. + */ +static void domain_add_cpu(int cpu, struct rdt_resource *r) +{ + int i, id = get_cache_id(cpu, r->cache_level); + struct list_head *add_pos = NULL; + struct rdt_domain *d; + + d = rdt_find_domain(r, id, &add_pos); + if (IS_ERR(d)) { + pr_warn("Could't find cache id for cpu %d\n", cpu); + return; + } + + if (d) { + cpumask_set_cpu(cpu, &d->cpu_mask); + return; + } + + d = kzalloc_node(sizeof(*d), GFP_KERNEL, cpu_to_node(cpu)); + if (!d) + return; + + d->id = id; + + d->cbm = kmalloc_array(r->num_closid, sizeof(*d->cbm), GFP_KERNEL); + if (!d->cbm) { + kfree(d); + return; + } + + for (i = 0; i < r->num_closid; i++) { + int idx = cbm_idx(r, i); + + d->cbm[i] = r->max_cbm; + wrmsrl(r->msr_base + idx, d->cbm[i]); + } + + cpumask_set_cpu(cpu, &d->cpu_mask); + list_add_tail(&d->list, add_pos); + r->num_domains++; +} + +static void domain_remove_cpu(int cpu, struct rdt_resource *r) +{ + int id = get_cache_id(cpu, r->cache_level); + struct rdt_domain *d; + + d = rdt_find_domain(r, id, NULL); + if (IS_ERR_OR_NULL(d)) { + pr_warn("Could't find cache id for cpu %d\n", cpu); + return; + } + + cpumask_clear_cpu(cpu, &d->cpu_mask); + if (cpumask_empty(&d->cpu_mask)) { + r->num_domains--; + kfree(d->cbm); + list_del(&d->list); + kfree(d); + } +} + +static void clear_closid(int cpu) +{ + struct intel_pqr_state *state = this_cpu_ptr(&pqr_state); + + per_cpu(cpu_closid, cpu) = 0; + state->closid = 0; + wrmsr(MSR_IA32_PQR_ASSOC, state->rmid, 0); +} + +static int intel_rdt_online_cpu(unsigned int cpu) +{ + struct rdt_resource *r; + + mutex_lock(&rdtgroup_mutex); + for_each_capable_rdt_resource(r) + domain_add_cpu(cpu, r); + /* The cpu is set in default rdtgroup after online. */ + cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask); + clear_closid(cpu); + mutex_unlock(&rdtgroup_mutex); + + return 0; +} + +static int intel_rdt_offline_cpu(unsigned int cpu) +{ + struct rdtgroup *rdtgrp; + struct rdt_resource *r; + + mutex_lock(&rdtgroup_mutex); + for_each_capable_rdt_resource(r) + domain_remove_cpu(cpu, r); + list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) { + if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask)) + break; + } + clear_closid(cpu); + mutex_unlock(&rdtgroup_mutex); + + return 0; +} + +static int __init intel_rdt_late_init(void) +{ + struct rdt_resource *r; + int state, ret; + + if (!get_rdt_resources()) + return -ENODEV; + + state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, + "x86/rdt/cat:online:", + intel_rdt_online_cpu, intel_rdt_offline_cpu); + if (state < 0) + return state; + + ret = rdtgroup_init(); + if (ret) { + cpuhp_remove_state(state); + return ret; + } + + for_each_capable_rdt_resource(r) + pr_info("Intel RDT %s allocation detected\n", r->name); + + return 0; +} + +late_initcall(intel_rdt_late_init); diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c new file mode 100644 index 000000000000..8af04afdfcb9 --- /dev/null +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -0,0 +1,1115 @@ +/* + * User interface for Resource Alloction in Resource Director Technology(RDT) + * + * Copyright (C) 2016 Intel Corporation + * + * Author: Fenghua Yu <fenghua.yu@intel.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * More information about RDT be found in the Intel (R) x86 Architecture + * Software Developer Manual. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/cpu.h> +#include <linux/fs.h> +#include <linux/sysfs.h> +#include <linux/kernfs.h> +#include <linux/seq_file.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/cpu.h> +#include <linux/task_work.h> + +#include <uapi/linux/magic.h> + +#include <asm/intel_rdt.h> +#include <asm/intel_rdt_common.h> + +DEFINE_STATIC_KEY_FALSE(rdt_enable_key); +struct kernfs_root *rdt_root; +struct rdtgroup rdtgroup_default; +LIST_HEAD(rdt_all_groups); + +/* Kernel fs node for "info" directory under root */ +static struct kernfs_node *kn_info; + +/* + * Trivial allocator for CLOSIDs. Since h/w only supports a small number, + * we can keep a bitmap of free CLOSIDs in a single integer. + * + * Using a global CLOSID across all resources has some advantages and + * some drawbacks: + * + We can simply set "current->closid" to assign a task to a resource + * group. + * + Context switch code can avoid extra memory references deciding which + * CLOSID to load into the PQR_ASSOC MSR + * - We give up some options in configuring resource groups across multi-socket + * systems. + * - Our choices on how to configure each resource become progressively more + * limited as the number of resources grows. + */ +static int closid_free_map; + +static void closid_init(void) +{ + struct rdt_resource *r; + int rdt_min_closid = 32; + + /* Compute rdt_min_closid across all resources */ + for_each_enabled_rdt_resource(r) + rdt_min_closid = min(rdt_min_closid, r->num_closid); + + closid_free_map = BIT_MASK(rdt_min_closid) - 1; + + /* CLOSID 0 is always reserved for the default group */ + closid_free_map &= ~1; +} + +int closid_alloc(void) +{ + int closid = ffs(closid_free_map); + + if (closid == 0) + return -ENOSPC; + closid--; + closid_free_map &= ~(1 << closid); + + return closid; +} + +static void closid_free(int closid) +{ + closid_free_map |= 1 << closid; +} + +/* set uid and gid of rdtgroup dirs and files to that of the creator */ +static int rdtgroup_kn_set_ugid(struct kernfs_node *kn) +{ + struct iattr iattr = { .ia_valid = ATTR_UID | ATTR_GID, + .ia_uid = current_fsuid(), + .ia_gid = current_fsgid(), }; + + if (uid_eq(iattr.ia_uid, GLOBAL_ROOT_UID) && + gid_eq(iattr.ia_gid, GLOBAL_ROOT_GID)) + return 0; + + return kernfs_setattr(kn, &iattr); +} + +static int rdtgroup_add_file(struct kernfs_node *parent_kn, struct rftype *rft) +{ + struct kernfs_node *kn; + int ret; + + kn = __kernfs_create_file(parent_kn, rft->name, rft->mode, + 0, rft->kf_ops, rft, NULL, NULL); + if (IS_ERR(kn)) + return PTR_ERR(kn); + + ret = rdtgroup_kn_set_ugid(kn); + if (ret) { + kernfs_remove(kn); + return ret; + } + + return 0; +} + +static int rdtgroup_add_files(struct kernfs_node *kn, struct rftype *rfts, + int len) +{ + struct rftype *rft; + int ret; + + lockdep_assert_held(&rdtgroup_mutex); + + for (rft = rfts; rft < rfts + len; rft++) { + ret = rdtgroup_add_file(kn, rft); + if (ret) + goto error; + } + + return 0; +error: + pr_warn("Failed to add %s, err=%d\n", rft->name, ret); + while (--rft >= rfts) + kernfs_remove_by_name(kn, rft->name); + return ret; +} + +static int rdtgroup_seqfile_show(struct seq_file *m, void *arg) +{ + struct kernfs_open_file *of = m->private; + struct rftype *rft = of->kn->priv; + + if (rft->seq_show) + return rft->seq_show(of, m, arg); + return 0; +} + +static ssize_t rdtgroup_file_write(struct kernfs_open_file *of, char *buf, + size_t nbytes, loff_t off) +{ + struct rftype *rft = of->kn->priv; + + if (rft->write) + return rft->write(of, buf, nbytes, off); + + return -EINVAL; +} + +static struct kernfs_ops rdtgroup_kf_single_ops = { + .atomic_write_len = PAGE_SIZE, + .write = rdtgroup_file_write, + .seq_show = rdtgroup_seqfile_show, +}; + +static int rdtgroup_cpus_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdtgroup *rdtgrp; + int ret = 0; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + + if (rdtgrp) + seq_printf(s, "%*pb\n", cpumask_pr_args(&rdtgrp->cpu_mask)); + else + ret = -ENOENT; + rdtgroup_kn_unlock(of->kn); + + return ret; +} + +/* + * This is safe against intel_rdt_sched_in() called from __switch_to() + * because __switch_to() is executed with interrupts disabled. A local call + * from rdt_update_closid() is proteced against __switch_to() because + * preemption is disabled. + */ +static void rdt_update_cpu_closid(void *closid) +{ + if (closid) + this_cpu_write(cpu_closid, *(int *)closid); + /* + * We cannot unconditionally write the MSR because the current + * executing task might have its own closid selected. Just reuse + * the context switch code. + */ + intel_rdt_sched_in(); +} + +/* + * Update the PGR_ASSOC MSR on all cpus in @cpu_mask, + * + * Per task closids must have been set up before calling this function. + * + * The per cpu closids are updated with the smp function call, when @closid + * is not NULL. If @closid is NULL then all affected percpu closids must + * have been set up before calling this function. + */ +static void +rdt_update_closid(const struct cpumask *cpu_mask, int *closid) +{ + int cpu = get_cpu(); + + if (cpumask_test_cpu(cpu, cpu_mask)) + rdt_update_cpu_closid(closid); + smp_call_function_many(cpu_mask, rdt_update_cpu_closid, closid, 1); + put_cpu(); +} + +static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + cpumask_var_t tmpmask, newmask; + struct rdtgroup *rdtgrp, *r; + int ret; + + if (!buf) + return -EINVAL; + + if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) + return -ENOMEM; + if (!zalloc_cpumask_var(&newmask, GFP_KERNEL)) { + free_cpumask_var(tmpmask); + return -ENOMEM; + } + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (!rdtgrp) { + ret = -ENOENT; + goto unlock; + } + + ret = cpumask_parse(buf, newmask); + if (ret) + goto unlock; + + /* check that user didn't specify any offline cpus */ + cpumask_andnot(tmpmask, newmask, cpu_online_mask); + if (cpumask_weight(tmpmask)) { + ret = -EINVAL; + goto unlock; + } + + /* Check whether cpus are dropped from this group */ + cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask); + if (cpumask_weight(tmpmask)) { + /* Can't drop from default group */ + if (rdtgrp == &rdtgroup_default) { + ret = -EINVAL; + goto unlock; + } + /* Give any dropped cpus to rdtgroup_default */ + cpumask_or(&rdtgroup_default.cpu_mask, + &rdtgroup_default.cpu_mask, tmpmask); + rdt_update_closid(tmpmask, &rdtgroup_default.closid); + } + + /* + * If we added cpus, remove them from previous group that owned them + * and update per-cpu closid + */ + cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask); + if (cpumask_weight(tmpmask)) { + list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) { + if (r == rdtgrp) + continue; + cpumask_andnot(&r->cpu_mask, &r->cpu_mask, tmpmask); + } + rdt_update_closid(tmpmask, &rdtgrp->closid); + } + + /* Done pushing/pulling - update this group with new mask */ + cpumask_copy(&rdtgrp->cpu_mask, newmask); + +unlock: + rdtgroup_kn_unlock(of->kn); + free_cpumask_var(tmpmask); + free_cpumask_var(newmask); + + return ret ?: nbytes; +} + +struct task_move_callback { + struct callback_head work; + struct rdtgroup *rdtgrp; +}; + +static void move_myself(struct callback_head *head) +{ + struct task_move_callback *callback; + struct rdtgroup *rdtgrp; + + callback = container_of(head, struct task_move_callback, work); + rdtgrp = callback->rdtgrp; + + /* + * If resource group was deleted before this task work callback + * was invoked, then assign the task to root group and free the + * resource group. + */ + if (atomic_dec_and_test(&rdtgrp->waitcount) && + (rdtgrp->flags & RDT_DELETED)) { + current->closid = 0; + kfree(rdtgrp); + } + + preempt_disable(); + /* update PQR_ASSOC MSR to make resource group go into effect */ + intel_rdt_sched_in(); + preempt_enable(); + + kfree(callback); +} + +static int __rdtgroup_move_task(struct task_struct *tsk, + struct rdtgroup *rdtgrp) +{ + struct task_move_callback *callback; + int ret; + + callback = kzalloc(sizeof(*callback), GFP_KERNEL); + if (!callback) + return -ENOMEM; + callback->work.func = move_myself; + callback->rdtgrp = rdtgrp; + + /* + * Take a refcount, so rdtgrp cannot be freed before the + * callback has been invoked. + */ + atomic_inc(&rdtgrp->waitcount); + ret = task_work_add(tsk, &callback->work, true); + if (ret) { + /* + * Task is exiting. Drop the refcount and free the callback. + * No need to check the refcount as the group cannot be + * deleted before the write function unlocks rdtgroup_mutex. + */ + atomic_dec(&rdtgrp->waitcount); + kfree(callback); + } else { + tsk->closid = rdtgrp->closid; + } + return ret; +} + +static int rdtgroup_task_write_permission(struct task_struct *task, + struct kernfs_open_file *of) +{ + const struct cred *tcred = get_task_cred(task); + const struct cred *cred = current_cred(); + int ret = 0; + + /* + * Even if we're attaching all tasks in the thread group, we only + * need to check permissions on one of them. + */ + if (!uid_eq(cred->euid, GLOBAL_ROOT_UID) && + !uid_eq(cred->euid, tcred->uid) && + !uid_eq(cred->euid, tcred->suid)) + ret = -EPERM; + + put_cred(tcred); + return ret; +} + +static int rdtgroup_move_task(pid_t pid, struct rdtgroup *rdtgrp, + struct kernfs_open_file *of) +{ + struct task_struct *tsk; + int ret; + + rcu_read_lock(); + if (pid) { + tsk = find_task_by_vpid(pid); + if (!tsk) { + rcu_read_unlock(); + return -ESRCH; + } + } else { + tsk = current; + } + + get_task_struct(tsk); + rcu_read_unlock(); + + ret = rdtgroup_task_write_permission(tsk, of); + if (!ret) + ret = __rdtgroup_move_task(tsk, rdtgrp); + + put_task_struct(tsk); + return ret; +} + +static ssize_t rdtgroup_tasks_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct rdtgroup *rdtgrp; + int ret = 0; + pid_t pid; + + if (kstrtoint(strstrip(buf), 0, &pid) || pid < 0) + return -EINVAL; + rdtgrp = rdtgroup_kn_lock_live(of->kn); + + if (rdtgrp) + ret = rdtgroup_move_task(pid, rdtgrp, of); + else + ret = -ENOENT; + + rdtgroup_kn_unlock(of->kn); + + return ret ?: nbytes; +} + +static void show_rdt_tasks(struct rdtgroup *r, struct seq_file *s) +{ + struct task_struct *p, *t; + + rcu_read_lock(); + for_each_process_thread(p, t) { + if (t->closid == r->closid) + seq_printf(s, "%d\n", t->pid); + } + rcu_read_unlock(); +} + +static int rdtgroup_tasks_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdtgroup *rdtgrp; + int ret = 0; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (rdtgrp) + show_rdt_tasks(rdtgrp, s); + else + ret = -ENOENT; + rdtgroup_kn_unlock(of->kn); + + return ret; +} + +/* Files in each rdtgroup */ +static struct rftype rdtgroup_base_files[] = { + { + .name = "cpus", + .mode = 0644, + .kf_ops = &rdtgroup_kf_single_ops, + .write = rdtgroup_cpus_write, + .seq_show = rdtgroup_cpus_show, + }, + { + .name = "tasks", + .mode = 0644, + .kf_ops = &rdtgroup_kf_single_ops, + .write = rdtgroup_tasks_write, + .seq_show = rdtgroup_tasks_show, + }, + { + .name = "schemata", + .mode = 0644, + .kf_ops = &rdtgroup_kf_single_ops, + .write = rdtgroup_schemata_write, + .seq_show = rdtgroup_schemata_show, + }, +}; + +static int rdt_num_closids_show(struct kernfs_open_file *of, + struct seq_file *seq, void *v) +{ + struct rdt_resource *r = of->kn->parent->priv; + + seq_printf(seq, "%d\n", r->num_closid); + + return 0; +} + +static int rdt_cbm_mask_show(struct kernfs_open_file *of, + struct seq_file *seq, void *v) +{ + struct rdt_resource *r = of->kn->parent->priv; + + seq_printf(seq, "%x\n", r->max_cbm); + + return 0; +} + +static int rdt_min_cbm_bits_show(struct kernfs_open_file *of, + struct seq_file *seq, void *v) +{ + struct rdt_resource *r = of->kn->parent->priv; + + seq_printf(seq, "%d\n", r->min_cbm_bits); + + return 0; +} + +/* rdtgroup information files for one cache resource. */ +static struct rftype res_info_files[] = { + { + .name = "num_closids", + .mode = 0444, + .kf_ops = &rdtgroup_kf_single_ops, + .seq_show = rdt_num_closids_show, + }, + { + .name = "cbm_mask", + .mode = 0444, + .kf_ops = &rdtgroup_kf_single_ops, + .seq_show = rdt_cbm_mask_show, + }, + { + .name = "min_cbm_bits", + .mode = 0444, + .kf_ops = &rdtgroup_kf_single_ops, + .seq_show = rdt_min_cbm_bits_show, + }, +}; + +static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn) +{ + struct kernfs_node *kn_subdir; + struct rdt_resource *r; + int ret; + + /* create the directory */ + kn_info = kernfs_create_dir(parent_kn, "info", parent_kn->mode, NULL); + if (IS_ERR(kn_info)) + return PTR_ERR(kn_info); + kernfs_get(kn_info); + + for_each_enabled_rdt_resource(r) { + kn_subdir = kernfs_create_dir(kn_info, r->name, + kn_info->mode, r); + if (IS_ERR(kn_subdir)) { + ret = PTR_ERR(kn_subdir); + goto out_destroy; + } + kernfs_get(kn_subdir); + ret = rdtgroup_kn_set_ugid(kn_subdir); + if (ret) + goto out_destroy; + ret = rdtgroup_add_files(kn_subdir, res_info_files, + ARRAY_SIZE(res_info_files)); + if (ret) + goto out_destroy; + kernfs_activate(kn_subdir); + } + + /* + * This extra ref will be put in kernfs_remove() and guarantees + * that @rdtgrp->kn is always accessible. + */ + kernfs_get(kn_info); + + ret = rdtgroup_kn_set_ugid(kn_info); + if (ret) + goto out_destroy; + + kernfs_activate(kn_info); + + return 0; + +out_destroy: + kernfs_remove(kn_info); + return ret; +} + +static void l3_qos_cfg_update(void *arg) +{ + bool *enable = arg; + + wrmsrl(IA32_L3_QOS_CFG, *enable ? L3_QOS_CDP_ENABLE : 0ULL); +} + +static int set_l3_qos_cfg(struct rdt_resource *r, bool enable) +{ + cpumask_var_t cpu_mask; + struct rdt_domain *d; + int cpu; + + if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) + return -ENOMEM; + + list_for_each_entry(d, &r->domains, list) { + /* Pick one CPU from each domain instance to update MSR */ + cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); + } + cpu = get_cpu(); + /* Update QOS_CFG MSR on this cpu if it's in cpu_mask. */ + if (cpumask_test_cpu(cpu, cpu_mask)) + l3_qos_cfg_update(&enable); + /* Update QOS_CFG MSR on all other cpus in cpu_mask. */ + smp_call_function_many(cpu_mask, l3_qos_cfg_update, &enable, 1); + put_cpu(); + + free_cpumask_var(cpu_mask); + + return 0; +} + +static int cdp_enable(void) +{ + struct rdt_resource *r_l3data = &rdt_resources_all[RDT_RESOURCE_L3DATA]; + struct rdt_resource *r_l3code = &rdt_resources_all[RDT_RESOURCE_L3CODE]; + struct rdt_resource *r_l3 = &rdt_resources_all[RDT_RESOURCE_L3]; + int ret; + + if (!r_l3->capable || !r_l3data->capable || !r_l3code->capable) + return -EINVAL; + + ret = set_l3_qos_cfg(r_l3, true); + if (!ret) { + r_l3->enabled = false; + r_l3data->enabled = true; + r_l3code->enabled = true; + } + return ret; +} + +static void cdp_disable(void) +{ + struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3]; + + r->enabled = r->capable; + + if (rdt_resources_all[RDT_RESOURCE_L3DATA].enabled) { + rdt_resources_all[RDT_RESOURCE_L3DATA].enabled = false; + rdt_resources_all[RDT_RESOURCE_L3CODE].enabled = false; + set_l3_qos_cfg(r, false); + } +} + +static int parse_rdtgroupfs_options(char *data) +{ + char *token, *o = data; + int ret = 0; + + while ((token = strsep(&o, ",")) != NULL) { + if (!*token) + return -EINVAL; + + if (!strcmp(token, "cdp")) + ret = cdp_enable(); + } + + return ret; +} + +/* + * We don't allow rdtgroup directories to be created anywhere + * except the root directory. Thus when looking for the rdtgroup + * structure for a kernfs node we are either looking at a directory, + * in which case the rdtgroup structure is pointed at by the "priv" + * field, otherwise we have a file, and need only look to the parent + * to find the rdtgroup. + */ +static struct rdtgroup *kernfs_to_rdtgroup(struct kernfs_node *kn) +{ + if (kernfs_type(kn) == KERNFS_DIR) { + /* + * All the resource directories use "kn->priv" + * to point to the "struct rdtgroup" for the + * resource. "info" and its subdirectories don't + * have rdtgroup structures, so return NULL here. + */ + if (kn == kn_info || kn->parent == kn_info) + return NULL; + else + return kn->priv; + } else { + return kn->parent->priv; + } +} + +struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn) +{ + struct rdtgroup *rdtgrp = kernfs_to_rdtgroup(kn); + + if (!rdtgrp) + return NULL; + + atomic_inc(&rdtgrp->waitcount); + kernfs_break_active_protection(kn); + + mutex_lock(&rdtgroup_mutex); + + /* Was this group deleted while we waited? */ + if (rdtgrp->flags & RDT_DELETED) + return NULL; + + return rdtgrp; +} + +void rdtgroup_kn_unlock(struct kernfs_node *kn) +{ + struct rdtgroup *rdtgrp = kernfs_to_rdtgroup(kn); + + if (!rdtgrp) + return; + + mutex_unlock(&rdtgroup_mutex); + + if (atomic_dec_and_test(&rdtgrp->waitcount) && + (rdtgrp->flags & RDT_DELETED)) { + kernfs_unbreak_active_protection(kn); + kernfs_put(kn); + kfree(rdtgrp); + } else { + kernfs_unbreak_active_protection(kn); + } +} + +static struct dentry *rdt_mount(struct file_system_type *fs_type, + int flags, const char *unused_dev_name, + void *data) +{ + struct dentry *dentry; + int ret; + + mutex_lock(&rdtgroup_mutex); + /* + * resctrl file system can only be mounted once. + */ + if (static_branch_unlikely(&rdt_enable_key)) { + dentry = ERR_PTR(-EBUSY); + goto out; + } + + ret = parse_rdtgroupfs_options(data); + if (ret) { + dentry = ERR_PTR(ret); + goto out_cdp; + } + + closid_init(); + + ret = rdtgroup_create_info_dir(rdtgroup_default.kn); + if (ret) { + dentry = ERR_PTR(ret); + goto out_cdp; + } + + dentry = kernfs_mount(fs_type, flags, rdt_root, + RDTGROUP_SUPER_MAGIC, NULL); + if (IS_ERR(dentry)) + goto out_cdp; + + static_branch_enable(&rdt_enable_key); + goto out; + +out_cdp: + cdp_disable(); +out: + mutex_unlock(&rdtgroup_mutex); + + return dentry; +} + +static int reset_all_cbms(struct rdt_resource *r) +{ + struct msr_param msr_param; + cpumask_var_t cpu_mask; + struct rdt_domain *d; + int i, cpu; + + if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) + return -ENOMEM; + + msr_param.res = r; + msr_param.low = 0; + msr_param.high = r->num_closid; + + /* + * Disable resource control for this resource by setting all + * CBMs in all domains to the maximum mask value. Pick one CPU + * from each domain to update the MSRs below. + */ + list_for_each_entry(d, &r->domains, list) { + cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); + + for (i = 0; i < r->num_closid; i++) + d->cbm[i] = r->max_cbm; + } + cpu = get_cpu(); + /* Update CBM on this cpu if it's in cpu_mask. */ + if (cpumask_test_cpu(cpu, cpu_mask)) + rdt_cbm_update(&msr_param); + /* Update CBM on all other cpus in cpu_mask. */ + smp_call_function_many(cpu_mask, rdt_cbm_update, &msr_param, 1); + put_cpu(); + + free_cpumask_var(cpu_mask); + + return 0; +} + +/* + * Move tasks from one to the other group. If @from is NULL, then all tasks + * in the systems are moved unconditionally (used for teardown). + * + * If @mask is not NULL the cpus on which moved tasks are running are set + * in that mask so the update smp function call is restricted to affected + * cpus. + */ +static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to, + struct cpumask *mask) +{ + struct task_struct *p, *t; + + read_lock(&tasklist_lock); + for_each_process_thread(p, t) { + if (!from || t->closid == from->closid) { + t->closid = to->closid; +#ifdef CONFIG_SMP + /* + * This is safe on x86 w/o barriers as the ordering + * of writing to task_cpu() and t->on_cpu is + * reverse to the reading here. The detection is + * inaccurate as tasks might move or schedule + * before the smp function call takes place. In + * such a case the function call is pointless, but + * there is no other side effect. + */ + if (mask && t->on_cpu) + cpumask_set_cpu(task_cpu(t), mask); +#endif + } + } + read_unlock(&tasklist_lock); +} + +/* + * Forcibly remove all of subdirectories under root. + */ +static void rmdir_all_sub(void) +{ + struct rdtgroup *rdtgrp, *tmp; + + /* Move all tasks to the default resource group */ + rdt_move_group_tasks(NULL, &rdtgroup_default, NULL); + + list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) { + /* Remove each rdtgroup other than root */ + if (rdtgrp == &rdtgroup_default) + continue; + + /* + * Give any CPUs back to the default group. We cannot copy + * cpu_online_mask because a CPU might have executed the + * offline callback already, but is still marked online. + */ + cpumask_or(&rdtgroup_default.cpu_mask, + &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask); + + kernfs_remove(rdtgrp->kn); + list_del(&rdtgrp->rdtgroup_list); + kfree(rdtgrp); + } + /* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */ + get_online_cpus(); + rdt_update_closid(cpu_online_mask, &rdtgroup_default.closid); + put_online_cpus(); + + kernfs_remove(kn_info); +} + +static void rdt_kill_sb(struct super_block *sb) +{ + struct rdt_resource *r; + + mutex_lock(&rdtgroup_mutex); + + /*Put everything back to default values. */ + for_each_enabled_rdt_resource(r) + reset_all_cbms(r); + cdp_disable(); + rmdir_all_sub(); + static_branch_disable(&rdt_enable_key); + kernfs_kill_sb(sb); + mutex_unlock(&rdtgroup_mutex); +} + +static struct file_system_type rdt_fs_type = { + .name = "resctrl", + .mount = rdt_mount, + .kill_sb = rdt_kill_sb, +}; + +static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name, + umode_t mode) +{ + struct rdtgroup *parent, *rdtgrp; + struct kernfs_node *kn; + int ret, closid; + + /* Only allow mkdir in the root directory */ + if (parent_kn != rdtgroup_default.kn) + return -EPERM; + + /* Do not accept '\n' to avoid unparsable situation. */ + if (strchr(name, '\n')) + return -EINVAL; + + parent = rdtgroup_kn_lock_live(parent_kn); + if (!parent) { + ret = -ENODEV; + goto out_unlock; + } + + ret = closid_alloc(); + if (ret < 0) + goto out_unlock; + closid = ret; + + /* allocate the rdtgroup. */ + rdtgrp = kzalloc(sizeof(*rdtgrp), GFP_KERNEL); + if (!rdtgrp) { + ret = -ENOSPC; + goto out_closid_free; + } + rdtgrp->closid = closid; + list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups); + + /* kernfs creates the directory for rdtgrp */ + kn = kernfs_create_dir(parent->kn, name, mode, rdtgrp); + if (IS_ERR(kn)) { + ret = PTR_ERR(kn); + goto out_cancel_ref; + } + rdtgrp->kn = kn; + + /* + * kernfs_remove() will drop the reference count on "kn" which + * will free it. But we still need it to stick around for the + * rdtgroup_kn_unlock(kn} call below. Take one extra reference + * here, which will be dropped inside rdtgroup_kn_unlock(). + */ + kernfs_get(kn); + + ret = rdtgroup_kn_set_ugid(kn); + if (ret) + goto out_destroy; + + ret = rdtgroup_add_files(kn, rdtgroup_base_files, + ARRAY_SIZE(rdtgroup_base_files)); + if (ret) + goto out_destroy; + + kernfs_activate(kn); + + ret = 0; + goto out_unlock; + +out_destroy: + kernfs_remove(rdtgrp->kn); +out_cancel_ref: + list_del(&rdtgrp->rdtgroup_list); + kfree(rdtgrp); +out_closid_free: + closid_free(closid); +out_unlock: + rdtgroup_kn_unlock(parent_kn); + return ret; +} + +static int rdtgroup_rmdir(struct kernfs_node *kn) +{ + int ret, cpu, closid = rdtgroup_default.closid; + struct rdtgroup *rdtgrp; + cpumask_var_t tmpmask; + + if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) + return -ENOMEM; + + rdtgrp = rdtgroup_kn_lock_live(kn); + if (!rdtgrp) { + ret = -EPERM; + goto out; + } + + /* Give any tasks back to the default group */ + rdt_move_group_tasks(rdtgrp, &rdtgroup_default, tmpmask); + + /* Give any CPUs back to the default group */ + cpumask_or(&rdtgroup_default.cpu_mask, + &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask); + + /* Update per cpu closid of the moved CPUs first */ + for_each_cpu(cpu, &rdtgrp->cpu_mask) + per_cpu(cpu_closid, cpu) = closid; + /* + * Update the MSR on moved CPUs and CPUs which have moved + * task running on them. + */ + cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask); + rdt_update_closid(tmpmask, NULL); + + rdtgrp->flags = RDT_DELETED; + closid_free(rdtgrp->closid); + list_del(&rdtgrp->rdtgroup_list); + + /* + * one extra hold on this, will drop when we kfree(rdtgrp) + * in rdtgroup_kn_unlock() + */ + kernfs_get(kn); + kernfs_remove(rdtgrp->kn); + ret = 0; +out: + rdtgroup_kn_unlock(kn); + free_cpumask_var(tmpmask); + return ret; +} + +static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf) +{ + if (rdt_resources_all[RDT_RESOURCE_L3DATA].enabled) + seq_puts(seq, ",cdp"); + return 0; +} + +static struct kernfs_syscall_ops rdtgroup_kf_syscall_ops = { + .mkdir = rdtgroup_mkdir, + .rmdir = rdtgroup_rmdir, + .show_options = rdtgroup_show_options, +}; + +static int __init rdtgroup_setup_root(void) +{ + int ret; + + rdt_root = kernfs_create_root(&rdtgroup_kf_syscall_ops, + KERNFS_ROOT_CREATE_DEACTIVATED, + &rdtgroup_default); + if (IS_ERR(rdt_root)) + return PTR_ERR(rdt_root); + + mutex_lock(&rdtgroup_mutex); + + rdtgroup_default.closid = 0; + list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups); + + ret = rdtgroup_add_files(rdt_root->kn, rdtgroup_base_files, + ARRAY_SIZE(rdtgroup_base_files)); + if (ret) { + kernfs_destroy_root(rdt_root); + goto out; + } + + rdtgroup_default.kn = rdt_root->kn; + kernfs_activate(rdtgroup_default.kn); + +out: + mutex_unlock(&rdtgroup_mutex); + + return ret; +} + +/* + * rdtgroup_init - rdtgroup initialization + * + * Setup resctrl file system including set up root, create mount point, + * register rdtgroup filesystem, and initialize files under root directory. + * + * Return: 0 on success or -errno + */ +int __init rdtgroup_init(void) +{ + int ret = 0; + + ret = rdtgroup_setup_root(); + if (ret) + return ret; + + ret = sysfs_create_mount_point(fs_kobj, "resctrl"); + if (ret) + goto cleanup_root; + + ret = register_filesystem(&rdt_fs_type); + if (ret) + goto cleanup_mountpoint; + + return 0; + +cleanup_mountpoint: + sysfs_remove_mount_point(fs_kobj, "resctrl"); +cleanup_root: + kernfs_destroy_root(rdt_root); + + return ret; +} diff --git a/arch/x86/kernel/cpu/intel_rdt_schemata.c b/arch/x86/kernel/cpu/intel_rdt_schemata.c new file mode 100644 index 000000000000..f369cb8db0d5 --- /dev/null +++ b/arch/x86/kernel/cpu/intel_rdt_schemata.c @@ -0,0 +1,245 @@ +/* + * Resource Director Technology(RDT) + * - Cache Allocation code. + * + * Copyright (C) 2016 Intel Corporation + * + * Authors: + * Fenghua Yu <fenghua.yu@intel.com> + * Tony Luck <tony.luck@intel.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * More information about RDT be found in the Intel (R) x86 Architecture + * Software Developer Manual June 2016, volume 3, section 17.17. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernfs.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <asm/intel_rdt.h> + +/* + * Check whether a cache bit mask is valid. The SDM says: + * Please note that all (and only) contiguous '1' combinations + * are allowed (e.g. FFFFH, 0FF0H, 003CH, etc.). + * Additionally Haswell requires at least two bits set. + */ +static bool cbm_validate(unsigned long var, struct rdt_resource *r) +{ + unsigned long first_bit, zero_bit; + + if (var == 0 || var > r->max_cbm) + return false; + + first_bit = find_first_bit(&var, r->cbm_len); + zero_bit = find_next_zero_bit(&var, r->cbm_len, first_bit); + + if (find_next_bit(&var, r->cbm_len, zero_bit) < r->cbm_len) + return false; + + if ((zero_bit - first_bit) < r->min_cbm_bits) + return false; + return true; +} + +/* + * Read one cache bit mask (hex). Check that it is valid for the current + * resource type. + */ +static int parse_cbm(char *buf, struct rdt_resource *r) +{ + unsigned long data; + int ret; + + ret = kstrtoul(buf, 16, &data); + if (ret) + return ret; + if (!cbm_validate(data, r)) + return -EINVAL; + r->tmp_cbms[r->num_tmp_cbms++] = data; + + return 0; +} + +/* + * For each domain in this resource we expect to find a series of: + * id=mask + * separated by ";". The "id" is in decimal, and must appear in the + * right order. + */ +static int parse_line(char *line, struct rdt_resource *r) +{ + char *dom = NULL, *id; + struct rdt_domain *d; + unsigned long dom_id; + + list_for_each_entry(d, &r->domains, list) { + dom = strsep(&line, ";"); + if (!dom) + return -EINVAL; + id = strsep(&dom, "="); + if (kstrtoul(id, 10, &dom_id) || dom_id != d->id) + return -EINVAL; + if (parse_cbm(dom, r)) + return -EINVAL; + } + + /* Any garbage at the end of the line? */ + if (line && line[0]) + return -EINVAL; + return 0; +} + +static int update_domains(struct rdt_resource *r, int closid) +{ + struct msr_param msr_param; + cpumask_var_t cpu_mask; + struct rdt_domain *d; + int cpu, idx = 0; + + if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) + return -ENOMEM; + + msr_param.low = closid; + msr_param.high = msr_param.low + 1; + msr_param.res = r; + + list_for_each_entry(d, &r->domains, list) { + cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); + d->cbm[msr_param.low] = r->tmp_cbms[idx++]; + } + cpu = get_cpu(); + /* Update CBM on this cpu if it's in cpu_mask. */ + if (cpumask_test_cpu(cpu, cpu_mask)) + rdt_cbm_update(&msr_param); + /* Update CBM on other cpus. */ + smp_call_function_many(cpu_mask, rdt_cbm_update, &msr_param, 1); + put_cpu(); + + free_cpumask_var(cpu_mask); + + return 0; +} + +ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct rdtgroup *rdtgrp; + struct rdt_resource *r; + char *tok, *resname; + int closid, ret = 0; + u32 *l3_cbms = NULL; + + /* Valid input requires a trailing newline */ + if (nbytes == 0 || buf[nbytes - 1] != '\n') + return -EINVAL; + buf[nbytes - 1] = '\0'; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (!rdtgrp) { + rdtgroup_kn_unlock(of->kn); + return -ENOENT; + } + + closid = rdtgrp->closid; + + /* get scratch space to save all the masks while we validate input */ + for_each_enabled_rdt_resource(r) { + r->tmp_cbms = kcalloc(r->num_domains, sizeof(*l3_cbms), + GFP_KERNEL); + if (!r->tmp_cbms) { + ret = -ENOMEM; + goto out; + } + r->num_tmp_cbms = 0; + } + + while ((tok = strsep(&buf, "\n")) != NULL) { + resname = strsep(&tok, ":"); + if (!tok) { + ret = -EINVAL; + goto out; + } + for_each_enabled_rdt_resource(r) { + if (!strcmp(resname, r->name) && + closid < r->num_closid) { + ret = parse_line(tok, r); + if (ret) + goto out; + break; + } + } + if (!r->name) { + ret = -EINVAL; + goto out; + } + } + + /* Did the parser find all the masks we need? */ + for_each_enabled_rdt_resource(r) { + if (r->num_tmp_cbms != r->num_domains) { + ret = -EINVAL; + goto out; + } + } + + for_each_enabled_rdt_resource(r) { + ret = update_domains(r, closid); + if (ret) + goto out; + } + +out: + rdtgroup_kn_unlock(of->kn); + for_each_enabled_rdt_resource(r) { + kfree(r->tmp_cbms); + r->tmp_cbms = NULL; + } + return ret ?: nbytes; +} + +static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid) +{ + struct rdt_domain *dom; + bool sep = false; + + seq_printf(s, "%s:", r->name); + list_for_each_entry(dom, &r->domains, list) { + if (sep) + seq_puts(s, ";"); + seq_printf(s, "%d=%x", dom->id, dom->cbm[closid]); + sep = true; + } + seq_puts(s, "\n"); +} + +int rdtgroup_schemata_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdtgroup *rdtgrp; + struct rdt_resource *r; + int closid, ret = 0; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (rdtgrp) { + closid = rdtgrp->closid; + for_each_enabled_rdt_resource(r) { + if (closid < r->num_closid) + show_doms(s, r, closid); + } + } else { + ret = -ENOENT; + } + rdtgroup_kn_unlock(of->kn); + return ret; +} diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index d1316f9c8329..d9794060fe22 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -20,12 +20,15 @@ struct cpuid_bit { /* Please keep the leaf sorted by cpuid_bit.level for faster search. */ static const struct cpuid_bit cpuid_bits[] = { { X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 }, - { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 }, - { X86_FEATURE_INTEL_PT, CPUID_EBX, 25, 0x00000007, 0 }, + { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 }, + { X86_FEATURE_INTEL_PT, CPUID_EBX, 25, 0x00000007, 0 }, { X86_FEATURE_AVX512_4VNNIW, CPUID_EDX, 2, 0x00000007, 0 }, { X86_FEATURE_AVX512_4FMAPS, CPUID_EDX, 3, 0x00000007, 0 }, - { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 }, - { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, + { X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 }, + { X86_FEATURE_CAT_L2, CPUID_EBX, 2, 0x00000010, 0 }, + { X86_FEATURE_CDP_L3, CPUID_ECX, 2, 0x00000010, 1 }, + { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 }, + { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 }, { 0, 0, 0, 0, 0 } }; |