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diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
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+/*
+ * 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);