diff options
| -rw-r--r-- | arch/x86/include/asm/intel_rdt.h | 26 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 271 | ||||
| -rw-r--r-- | include/uapi/linux/magic.h | 1 |
5 files changed, 306 insertions, 2 deletions
diff --git a/arch/x86/include/asm/intel_rdt.h b/arch/x86/include/asm/intel_rdt.h index c0d0a6e6448c..09d00e6f7ad6 100644 --- a/arch/x86/include/asm/intel_rdt.h +++ b/arch/x86/include/asm/intel_rdt.h @@ -1,9 +1,31 @@ #ifndef _ASM_X86_INTEL_RDT_H #define _ASM_X86_INTEL_RDT_H +#include <linux/jump_label.h> + +#define IA32_L3_QOS_CFG 0xc81 #define IA32_L3_CBM_BASE 0xc90 #define IA32_L2_CBM_BASE 0xd10 +#define L3_QOS_CDP_ENABLE 0x01ULL + +/** + * struct rdtgroup - store rdtgroup's data in resctrl file system. + * @kn: kernfs node + * @rdtgroup_list: linked list for all rdtgroups + * @closid: closid for this rdtgroup + */ +struct rdtgroup { + struct kernfs_node *kn; + struct list_head rdtgroup_list; + int closid; +}; + +/* List of all resource groups */ +extern struct list_head rdt_all_groups; + +int __init rdtgroup_init(void); + /** * struct rdt_resource - attributes of an RDT resource * @enabled: Is this feature enabled on this machine @@ -68,6 +90,10 @@ struct msr_param { extern struct mutex rdtgroup_mutex; extern struct rdt_resource rdt_resources_all[]; +extern struct rdtgroup rdtgroup_default; +DECLARE_STATIC_KEY_FALSE(rdt_enable_key); + +int __init rdtgroup_init(void); enum { RDT_RESOURCE_L3, diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index cf4bfd030c0c..b4334e86c1a9 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -34,7 +34,7 @@ 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 +obj-$(CONFIG_INTEL_RDT_A) += intel_rdt.o intel_rdt_rdtgroup.o obj-$(CONFIG_X86_MCE) += mcheck/ obj-$(CONFIG_MTRR) += mtrr/ diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c index 3d4b397a1181..9d95414f7117 100644 --- a/arch/x86/kernel/cpu/intel_rdt.c +++ b/arch/x86/kernel/cpu/intel_rdt.c @@ -361,7 +361,7 @@ static int intel_rdt_offline_cpu(unsigned int cpu) static int __init intel_rdt_late_init(void) { struct rdt_resource *r; - int state; + int state, ret; if (!get_rdt_resources()) return -ENODEV; @@ -372,6 +372,12 @@ static int __init intel_rdt_late_init(void) 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); 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..106e4ce8f7e0 --- /dev/null +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -0,0 +1,271 @@ +/* + * 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/fs.h> +#include <linux/sysfs.h> +#include <linux/kernfs.h> +#include <linux/slab.h> + +#include <uapi/linux/magic.h> + +#include <asm/intel_rdt.h> + +DEFINE_STATIC_KEY_FALSE(rdt_enable_key); +struct kernfs_root *rdt_root; +struct rdtgroup rdtgroup_default; +LIST_HEAD(rdt_all_groups); + +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; +} + +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; + } + + 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; +} + +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(); + 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 struct kernfs_syscall_ops rdtgroup_kf_syscall_ops = { +}; + +static int __init rdtgroup_setup_root(void) +{ + 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); + + rdtgroup_default.kn = rdt_root->kn; + kernfs_activate(rdtgroup_default.kn); + + mutex_unlock(&rdtgroup_mutex); + + return 0; +} + +/* + * 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/include/uapi/linux/magic.h b/include/uapi/linux/magic.h index 9bd559472c92..e230af2e6855 100644 --- a/include/uapi/linux/magic.h +++ b/include/uapi/linux/magic.h @@ -57,6 +57,7 @@ #define CGROUP_SUPER_MAGIC 0x27e0eb #define CGROUP2_SUPER_MAGIC 0x63677270 +#define RDTGROUP_SUPER_MAGIC 0x7655821 #define STACK_END_MAGIC 0x57AC6E9D |