| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * User interface for Resource Allocation in Resource Director Technology(RDT) |
| * |
| * Copyright (C) 2016 Intel Corporation |
| * |
| * Author: Fenghua Yu <fenghua.yu@intel.com> |
| * |
| * More information about RDT be found in the Intel (R) x86 Architecture |
| * Software Developer Manual. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/cacheinfo.h> |
| #include <linux/cpu.h> |
| #include <linux/debugfs.h> |
| #include <linux/fs.h> |
| #include <linux/fs_parser.h> |
| #include <linux/sysfs.h> |
| #include <linux/kernfs.h> |
| #include <linux/seq_buf.h> |
| #include <linux/seq_file.h> |
| #include <linux/sched/signal.h> |
| #include <linux/sched/task.h> |
| #include <linux/slab.h> |
| #include <linux/task_work.h> |
| #include <linux/user_namespace.h> |
| |
| #include <uapi/linux/magic.h> |
| |
| #include <asm/resctrl.h> |
| #include "internal.h" |
| |
| DEFINE_STATIC_KEY_FALSE(rdt_enable_key); |
| DEFINE_STATIC_KEY_FALSE(rdt_mon_enable_key); |
| DEFINE_STATIC_KEY_FALSE(rdt_alloc_enable_key); |
| static struct kernfs_root *rdt_root; |
| struct rdtgroup rdtgroup_default; |
| LIST_HEAD(rdt_all_groups); |
| |
| /* list of entries for the schemata file */ |
| LIST_HEAD(resctrl_schema_all); |
| |
| /* Kernel fs node for "info" directory under root */ |
| static struct kernfs_node *kn_info; |
| |
| /* Kernel fs node for "mon_groups" directory under root */ |
| static struct kernfs_node *kn_mongrp; |
| |
| /* Kernel fs node for "mon_data" directory under root */ |
| static struct kernfs_node *kn_mondata; |
| |
| static struct seq_buf last_cmd_status; |
| static char last_cmd_status_buf[512]; |
| |
| struct dentry *debugfs_resctrl; |
| |
| void rdt_last_cmd_clear(void) |
| { |
| lockdep_assert_held(&rdtgroup_mutex); |
| seq_buf_clear(&last_cmd_status); |
| } |
| |
| void rdt_last_cmd_puts(const char *s) |
| { |
| lockdep_assert_held(&rdtgroup_mutex); |
| seq_buf_puts(&last_cmd_status, s); |
| } |
| |
| void rdt_last_cmd_printf(const char *fmt, ...) |
| { |
| va_list ap; |
| |
| va_start(ap, fmt); |
| lockdep_assert_held(&rdtgroup_mutex); |
| seq_buf_vprintf(&last_cmd_status, fmt, ap); |
| va_end(ap); |
| } |
| |
| void rdt_staged_configs_clear(void) |
| { |
| struct rdt_resource *r; |
| struct rdt_domain *dom; |
| |
| lockdep_assert_held(&rdtgroup_mutex); |
| |
| for_each_alloc_capable_rdt_resource(r) { |
| list_for_each_entry(dom, &r->domains, list) |
| memset(dom->staged_config, 0, sizeof(dom->staged_config)); |
| } |
| } |
| |
| /* |
| * 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 int closid_free_map_len; |
| |
| int closids_supported(void) |
| { |
| return closid_free_map_len; |
| } |
| |
| static void closid_init(void) |
| { |
| struct resctrl_schema *s; |
| u32 rdt_min_closid = 32; |
| |
| /* Compute rdt_min_closid across all resources */ |
| list_for_each_entry(s, &resctrl_schema_all, list) |
| rdt_min_closid = min(rdt_min_closid, s->num_closid); |
| |
| closid_free_map = BIT_MASK(rdt_min_closid) - 1; |
| |
| /* CLOSID 0 is always reserved for the default group */ |
| closid_free_map &= ~1; |
| closid_free_map_len = rdt_min_closid; |
| } |
| |
| static int closid_alloc(void) |
| { |
| u32 closid = ffs(closid_free_map); |
| |
| if (closid == 0) |
| return -ENOSPC; |
| closid--; |
| closid_free_map &= ~(1 << closid); |
| |
| return closid; |
| } |
| |
| void closid_free(int closid) |
| { |
| closid_free_map |= 1 << closid; |
| } |
| |
| /** |
| * closid_allocated - test if provided closid is in use |
| * @closid: closid to be tested |
| * |
| * Return: true if @closid is currently associated with a resource group, |
| * false if @closid is free |
| */ |
| static bool closid_allocated(unsigned int closid) |
| { |
| return (closid_free_map & (1 << closid)) == 0; |
| } |
| |
| /** |
| * rdtgroup_mode_by_closid - Return mode of resource group with closid |
| * @closid: closid if the resource group |
| * |
| * Each resource group is associated with a @closid. Here the mode |
| * of a resource group can be queried by searching for it using its closid. |
| * |
| * Return: mode as &enum rdtgrp_mode of resource group with closid @closid |
| */ |
| enum rdtgrp_mode rdtgroup_mode_by_closid(int closid) |
| { |
| struct rdtgroup *rdtgrp; |
| |
| list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) { |
| if (rdtgrp->closid == closid) |
| return rdtgrp->mode; |
| } |
| |
| return RDT_NUM_MODES; |
| } |
| |
| static const char * const rdt_mode_str[] = { |
| [RDT_MODE_SHAREABLE] = "shareable", |
| [RDT_MODE_EXCLUSIVE] = "exclusive", |
| [RDT_MODE_PSEUDO_LOCKSETUP] = "pseudo-locksetup", |
| [RDT_MODE_PSEUDO_LOCKED] = "pseudo-locked", |
| }; |
| |
| /** |
| * rdtgroup_mode_str - Return the string representation of mode |
| * @mode: the resource group mode as &enum rdtgroup_mode |
| * |
| * Return: string representation of valid mode, "unknown" otherwise |
| */ |
| static const char *rdtgroup_mode_str(enum rdtgrp_mode mode) |
| { |
| if (mode < RDT_MODE_SHAREABLE || mode >= RDT_NUM_MODES) |
| return "unknown"; |
| |
| return rdt_mode_str[mode]; |
| } |
| |
| /* 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, |
| GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, |
| 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_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 const struct kernfs_ops rdtgroup_kf_single_ops = { |
| .atomic_write_len = PAGE_SIZE, |
| .write = rdtgroup_file_write, |
| .seq_show = rdtgroup_seqfile_show, |
| }; |
| |
| static const struct kernfs_ops kf_mondata_ops = { |
| .atomic_write_len = PAGE_SIZE, |
| .seq_show = rdtgroup_mondata_show, |
| }; |
| |
| static bool is_cpu_list(struct kernfs_open_file *of) |
| { |
| struct rftype *rft = of->kn->priv; |
| |
| return rft->flags & RFTYPE_FLAGS_CPUS_LIST; |
| } |
| |
| static int rdtgroup_cpus_show(struct kernfs_open_file *of, |
| struct seq_file *s, void *v) |
| { |
| struct rdtgroup *rdtgrp; |
| struct cpumask *mask; |
| int ret = 0; |
| |
| rdtgrp = rdtgroup_kn_lock_live(of->kn); |
| |
| if (rdtgrp) { |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) { |
| if (!rdtgrp->plr->d) { |
| rdt_last_cmd_clear(); |
| rdt_last_cmd_puts("Cache domain offline\n"); |
| ret = -ENODEV; |
| } else { |
| mask = &rdtgrp->plr->d->cpu_mask; |
| seq_printf(s, is_cpu_list(of) ? |
| "%*pbl\n" : "%*pb\n", |
| cpumask_pr_args(mask)); |
| } |
| } else { |
| seq_printf(s, is_cpu_list(of) ? "%*pbl\n" : "%*pb\n", |
| cpumask_pr_args(&rdtgrp->cpu_mask)); |
| } |
| } else { |
| ret = -ENOENT; |
| } |
| rdtgroup_kn_unlock(of->kn); |
| |
| return ret; |
| } |
| |
| /* |
| * This is safe against resctrl_sched_in() called from __switch_to() |
| * because __switch_to() is executed with interrupts disabled. A local call |
| * from update_closid_rmid() is protected against __switch_to() because |
| * preemption is disabled. |
| */ |
| static void update_cpu_closid_rmid(void *info) |
| { |
| struct rdtgroup *r = info; |
| |
| if (r) { |
| this_cpu_write(pqr_state.default_closid, r->closid); |
| this_cpu_write(pqr_state.default_rmid, r->mon.rmid); |
| } |
| |
| /* |
| * We cannot unconditionally write the MSR because the current |
| * executing task might have its own closid selected. Just reuse |
| * the context switch code. |
| */ |
| resctrl_sched_in(current); |
| } |
| |
| /* |
| * Update the PGR_ASSOC MSR on all cpus in @cpu_mask, |
| * |
| * Per task closids/rmids must have been set up before calling this function. |
| */ |
| static void |
| update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r) |
| { |
| int cpu = get_cpu(); |
| |
| if (cpumask_test_cpu(cpu, cpu_mask)) |
| update_cpu_closid_rmid(r); |
| smp_call_function_many(cpu_mask, update_cpu_closid_rmid, r, 1); |
| put_cpu(); |
| } |
| |
| static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask, |
| cpumask_var_t tmpmask) |
| { |
| struct rdtgroup *prgrp = rdtgrp->mon.parent, *crgrp; |
| struct list_head *head; |
| |
| /* Check whether cpus belong to parent ctrl group */ |
| cpumask_andnot(tmpmask, newmask, &prgrp->cpu_mask); |
| if (!cpumask_empty(tmpmask)) { |
| rdt_last_cmd_puts("Can only add CPUs to mongroup that belong to parent\n"); |
| return -EINVAL; |
| } |
| |
| /* Check whether cpus are dropped from this group */ |
| cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask); |
| if (!cpumask_empty(tmpmask)) { |
| /* Give any dropped cpus to parent rdtgroup */ |
| cpumask_or(&prgrp->cpu_mask, &prgrp->cpu_mask, tmpmask); |
| update_closid_rmid(tmpmask, prgrp); |
| } |
| |
| /* |
| * If we added cpus, remove them from previous group that owned them |
| * and update per-cpu rmid |
| */ |
| cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask); |
| if (!cpumask_empty(tmpmask)) { |
| head = &prgrp->mon.crdtgrp_list; |
| list_for_each_entry(crgrp, head, mon.crdtgrp_list) { |
| if (crgrp == rdtgrp) |
| continue; |
| cpumask_andnot(&crgrp->cpu_mask, &crgrp->cpu_mask, |
| tmpmask); |
| } |
| update_closid_rmid(tmpmask, rdtgrp); |
| } |
| |
| /* Done pushing/pulling - update this group with new mask */ |
| cpumask_copy(&rdtgrp->cpu_mask, newmask); |
| |
| return 0; |
| } |
| |
| static void cpumask_rdtgrp_clear(struct rdtgroup *r, struct cpumask *m) |
| { |
| struct rdtgroup *crgrp; |
| |
| cpumask_andnot(&r->cpu_mask, &r->cpu_mask, m); |
| /* update the child mon group masks as well*/ |
| list_for_each_entry(crgrp, &r->mon.crdtgrp_list, mon.crdtgrp_list) |
| cpumask_and(&crgrp->cpu_mask, &r->cpu_mask, &crgrp->cpu_mask); |
| } |
| |
| static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask, |
| cpumask_var_t tmpmask, cpumask_var_t tmpmask1) |
| { |
| struct rdtgroup *r, *crgrp; |
| struct list_head *head; |
| |
| /* Check whether cpus are dropped from this group */ |
| cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask); |
| if (!cpumask_empty(tmpmask)) { |
| /* Can't drop from default group */ |
| if (rdtgrp == &rdtgroup_default) { |
| rdt_last_cmd_puts("Can't drop CPUs from default group\n"); |
| return -EINVAL; |
| } |
| |
| /* Give any dropped cpus to rdtgroup_default */ |
| cpumask_or(&rdtgroup_default.cpu_mask, |
| &rdtgroup_default.cpu_mask, tmpmask); |
| update_closid_rmid(tmpmask, &rdtgroup_default); |
| } |
| |
| /* |
| * If we added cpus, remove them from previous group and |
| * the prev group's child groups that owned them |
| * and update per-cpu closid/rmid. |
| */ |
| cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask); |
| if (!cpumask_empty(tmpmask)) { |
| list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) { |
| if (r == rdtgrp) |
| continue; |
| cpumask_and(tmpmask1, &r->cpu_mask, tmpmask); |
| if (!cpumask_empty(tmpmask1)) |
| cpumask_rdtgrp_clear(r, tmpmask1); |
| } |
| update_closid_rmid(tmpmask, rdtgrp); |
| } |
| |
| /* Done pushing/pulling - update this group with new mask */ |
| cpumask_copy(&rdtgrp->cpu_mask, newmask); |
| |
| /* |
| * Clear child mon group masks since there is a new parent mask |
| * now and update the rmid for the cpus the child lost. |
| */ |
| head = &rdtgrp->mon.crdtgrp_list; |
| list_for_each_entry(crgrp, head, mon.crdtgrp_list) { |
| cpumask_and(tmpmask, &rdtgrp->cpu_mask, &crgrp->cpu_mask); |
| update_closid_rmid(tmpmask, rdtgrp); |
| cpumask_clear(&crgrp->cpu_mask); |
| } |
| |
| return 0; |
| } |
| |
| static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of, |
| char *buf, size_t nbytes, loff_t off) |
| { |
| cpumask_var_t tmpmask, newmask, tmpmask1; |
| struct rdtgroup *rdtgrp; |
| 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; |
| } |
| if (!zalloc_cpumask_var(&tmpmask1, GFP_KERNEL)) { |
| free_cpumask_var(tmpmask); |
| free_cpumask_var(newmask); |
| return -ENOMEM; |
| } |
| |
| rdtgrp = rdtgroup_kn_lock_live(of->kn); |
| if (!rdtgrp) { |
| ret = -ENOENT; |
| goto unlock; |
| } |
| |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED || |
| rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { |
| ret = -EINVAL; |
| rdt_last_cmd_puts("Pseudo-locking in progress\n"); |
| goto unlock; |
| } |
| |
| if (is_cpu_list(of)) |
| ret = cpulist_parse(buf, newmask); |
| else |
| ret = cpumask_parse(buf, newmask); |
| |
| if (ret) { |
| rdt_last_cmd_puts("Bad CPU list/mask\n"); |
| goto unlock; |
| } |
| |
| /* check that user didn't specify any offline cpus */ |
| cpumask_andnot(tmpmask, newmask, cpu_online_mask); |
| if (!cpumask_empty(tmpmask)) { |
| ret = -EINVAL; |
| rdt_last_cmd_puts("Can only assign online CPUs\n"); |
| goto unlock; |
| } |
| |
| if (rdtgrp->type == RDTCTRL_GROUP) |
| ret = cpus_ctrl_write(rdtgrp, newmask, tmpmask, tmpmask1); |
| else if (rdtgrp->type == RDTMON_GROUP) |
| ret = cpus_mon_write(rdtgrp, newmask, tmpmask); |
| else |
| ret = -EINVAL; |
| |
| unlock: |
| rdtgroup_kn_unlock(of->kn); |
| free_cpumask_var(tmpmask); |
| free_cpumask_var(newmask); |
| free_cpumask_var(tmpmask1); |
| |
| return ret ?: nbytes; |
| } |
| |
| /** |
| * rdtgroup_remove - the helper to remove resource group safely |
| * @rdtgrp: resource group to remove |
| * |
| * On resource group creation via a mkdir, an extra kernfs_node reference is |
| * taken to ensure that the rdtgroup structure remains accessible for the |
| * rdtgroup_kn_unlock() calls where it is removed. |
| * |
| * Drop the extra reference here, then free the rdtgroup structure. |
| * |
| * Return: void |
| */ |
| static void rdtgroup_remove(struct rdtgroup *rdtgrp) |
| { |
| kernfs_put(rdtgrp->kn); |
| kfree(rdtgrp); |
| } |
| |
| static void _update_task_closid_rmid(void *task) |
| { |
| /* |
| * If the task is still current on this CPU, update PQR_ASSOC MSR. |
| * Otherwise, the MSR is updated when the task is scheduled in. |
| */ |
| if (task == current) |
| resctrl_sched_in(task); |
| } |
| |
| static void update_task_closid_rmid(struct task_struct *t) |
| { |
| if (IS_ENABLED(CONFIG_SMP) && task_curr(t)) |
| smp_call_function_single(task_cpu(t), _update_task_closid_rmid, t, 1); |
| else |
| _update_task_closid_rmid(t); |
| } |
| |
| static int __rdtgroup_move_task(struct task_struct *tsk, |
| struct rdtgroup *rdtgrp) |
| { |
| /* If the task is already in rdtgrp, no need to move the task. */ |
| if ((rdtgrp->type == RDTCTRL_GROUP && tsk->closid == rdtgrp->closid && |
| tsk->rmid == rdtgrp->mon.rmid) || |
| (rdtgrp->type == RDTMON_GROUP && tsk->rmid == rdtgrp->mon.rmid && |
| tsk->closid == rdtgrp->mon.parent->closid)) |
| return 0; |
| |
| /* |
| * Set the task's closid/rmid before the PQR_ASSOC MSR can be |
| * updated by them. |
| * |
| * For ctrl_mon groups, move both closid and rmid. |
| * For monitor groups, can move the tasks only from |
| * their parent CTRL group. |
| */ |
| |
| if (rdtgrp->type == RDTCTRL_GROUP) { |
| WRITE_ONCE(tsk->closid, rdtgrp->closid); |
| WRITE_ONCE(tsk->rmid, rdtgrp->mon.rmid); |
| } else if (rdtgrp->type == RDTMON_GROUP) { |
| if (rdtgrp->mon.parent->closid == tsk->closid) { |
| WRITE_ONCE(tsk->rmid, rdtgrp->mon.rmid); |
| } else { |
| rdt_last_cmd_puts("Can't move task to different control group\n"); |
| return -EINVAL; |
| } |
| } |
| |
| /* |
| * Ensure the task's closid and rmid are written before determining if |
| * the task is current that will decide if it will be interrupted. |
| * This pairs with the full barrier between the rq->curr update and |
| * resctrl_sched_in() during context switch. |
| */ |
| smp_mb(); |
| |
| /* |
| * By now, the task's closid and rmid are set. If the task is current |
| * on a CPU, the PQR_ASSOC MSR needs to be updated to make the resource |
| * group go into effect. If the task is not current, the MSR will be |
| * updated when the task is scheduled in. |
| */ |
| update_task_closid_rmid(tsk); |
| |
| return 0; |
| } |
| |
| static bool is_closid_match(struct task_struct *t, struct rdtgroup *r) |
| { |
| return (rdt_alloc_capable && |
| (r->type == RDTCTRL_GROUP) && (t->closid == r->closid)); |
| } |
| |
| static bool is_rmid_match(struct task_struct *t, struct rdtgroup *r) |
| { |
| return (rdt_mon_capable && |
| (r->type == RDTMON_GROUP) && (t->rmid == r->mon.rmid)); |
| } |
| |
| /** |
| * rdtgroup_tasks_assigned - Test if tasks have been assigned to resource group |
| * @r: Resource group |
| * |
| * Return: 1 if tasks have been assigned to @r, 0 otherwise |
| */ |
| int rdtgroup_tasks_assigned(struct rdtgroup *r) |
| { |
| struct task_struct *p, *t; |
| int ret = 0; |
| |
| lockdep_assert_held(&rdtgroup_mutex); |
| |
| rcu_read_lock(); |
| for_each_process_thread(p, t) { |
| if (is_closid_match(t, r) || is_rmid_match(t, r)) { |
| ret = 1; |
| break; |
| } |
| } |
| rcu_read_unlock(); |
| |
| 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)) { |
| rdt_last_cmd_printf("No permission to move task %d\n", task->pid); |
| 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(); |
| rdt_last_cmd_printf("No task %d\n", pid); |
| 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) { |
| rdtgroup_kn_unlock(of->kn); |
| return -ENOENT; |
| } |
| rdt_last_cmd_clear(); |
| |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED || |
| rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { |
| ret = -EINVAL; |
| rdt_last_cmd_puts("Pseudo-locking in progress\n"); |
| goto unlock; |
| } |
| |
| ret = rdtgroup_move_task(pid, rdtgrp, of); |
| |
| unlock: |
| 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; |
| pid_t pid; |
| |
| rcu_read_lock(); |
| for_each_process_thread(p, t) { |
| if (is_closid_match(t, r) || is_rmid_match(t, r)) { |
| pid = task_pid_vnr(t); |
| if (pid) |
| seq_printf(s, "%d\n", 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; |
| } |
| |
| #ifdef CONFIG_PROC_CPU_RESCTRL |
| |
| /* |
| * A task can only be part of one resctrl control group and of one monitor |
| * group which is associated to that control group. |
| * |
| * 1) res: |
| * mon: |
| * |
| * resctrl is not available. |
| * |
| * 2) res:/ |
| * mon: |
| * |
| * Task is part of the root resctrl control group, and it is not associated |
| * to any monitor group. |
| * |
| * 3) res:/ |
| * mon:mon0 |
| * |
| * Task is part of the root resctrl control group and monitor group mon0. |
| * |
| * 4) res:group0 |
| * mon: |
| * |
| * Task is part of resctrl control group group0, and it is not associated |
| * to any monitor group. |
| * |
| * 5) res:group0 |
| * mon:mon1 |
| * |
| * Task is part of resctrl control group group0 and monitor group mon1. |
| */ |
| int proc_resctrl_show(struct seq_file *s, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *tsk) |
| { |
| struct rdtgroup *rdtg; |
| int ret = 0; |
| |
| mutex_lock(&rdtgroup_mutex); |
| |
| /* Return empty if resctrl has not been mounted. */ |
| if (!static_branch_unlikely(&rdt_enable_key)) { |
| seq_puts(s, "res:\nmon:\n"); |
| goto unlock; |
| } |
| |
| list_for_each_entry(rdtg, &rdt_all_groups, rdtgroup_list) { |
| struct rdtgroup *crg; |
| |
| /* |
| * Task information is only relevant for shareable |
| * and exclusive groups. |
| */ |
| if (rdtg->mode != RDT_MODE_SHAREABLE && |
| rdtg->mode != RDT_MODE_EXCLUSIVE) |
| continue; |
| |
| if (rdtg->closid != tsk->closid) |
| continue; |
| |
| seq_printf(s, "res:%s%s\n", (rdtg == &rdtgroup_default) ? "/" : "", |
| rdtg->kn->name); |
| seq_puts(s, "mon:"); |
| list_for_each_entry(crg, &rdtg->mon.crdtgrp_list, |
| mon.crdtgrp_list) { |
| if (tsk->rmid != crg->mon.rmid) |
| continue; |
| seq_printf(s, "%s", crg->kn->name); |
| break; |
| } |
| seq_putc(s, '\n'); |
| goto unlock; |
| } |
| /* |
| * The above search should succeed. Otherwise return |
| * with an error. |
| */ |
| ret = -ENOENT; |
| unlock: |
| mutex_unlock(&rdtgroup_mutex); |
| |
| return ret; |
| } |
| #endif |
| |
| static int rdt_last_cmd_status_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| int len; |
| |
| mutex_lock(&rdtgroup_mutex); |
| len = seq_buf_used(&last_cmd_status); |
| if (len) |
| seq_printf(seq, "%.*s", len, last_cmd_status_buf); |
| else |
| seq_puts(seq, "ok\n"); |
| mutex_unlock(&rdtgroup_mutex); |
| return 0; |
| } |
| |
| static int rdt_num_closids_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| |
| seq_printf(seq, "%u\n", s->num_closid); |
| return 0; |
| } |
| |
| static int rdt_default_ctrl_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| seq_printf(seq, "%x\n", r->default_ctrl); |
| return 0; |
| } |
| |
| static int rdt_min_cbm_bits_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| seq_printf(seq, "%u\n", r->cache.min_cbm_bits); |
| return 0; |
| } |
| |
| static int rdt_shareable_bits_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| seq_printf(seq, "%x\n", r->cache.shareable_bits); |
| return 0; |
| } |
| |
| /** |
| * rdt_bit_usage_show - Display current usage of resources |
| * |
| * A domain is a shared resource that can now be allocated differently. Here |
| * we display the current regions of the domain as an annotated bitmask. |
| * For each domain of this resource its allocation bitmask |
| * is annotated as below to indicate the current usage of the corresponding bit: |
| * 0 - currently unused |
| * X - currently available for sharing and used by software and hardware |
| * H - currently used by hardware only but available for software use |
| * S - currently used and shareable by software only |
| * E - currently used exclusively by one resource group |
| * P - currently pseudo-locked by one resource group |
| */ |
| static int rdt_bit_usage_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| /* |
| * Use unsigned long even though only 32 bits are used to ensure |
| * test_bit() is used safely. |
| */ |
| unsigned long sw_shareable = 0, hw_shareable = 0; |
| unsigned long exclusive = 0, pseudo_locked = 0; |
| struct rdt_resource *r = s->res; |
| struct rdt_domain *dom; |
| int i, hwb, swb, excl, psl; |
| enum rdtgrp_mode mode; |
| bool sep = false; |
| u32 ctrl_val; |
| |
| mutex_lock(&rdtgroup_mutex); |
| hw_shareable = r->cache.shareable_bits; |
| list_for_each_entry(dom, &r->domains, list) { |
| if (sep) |
| seq_putc(seq, ';'); |
| sw_shareable = 0; |
| exclusive = 0; |
| seq_printf(seq, "%d=", dom->id); |
| for (i = 0; i < closids_supported(); i++) { |
| if (!closid_allocated(i)) |
| continue; |
| ctrl_val = resctrl_arch_get_config(r, dom, i, |
| s->conf_type); |
| mode = rdtgroup_mode_by_closid(i); |
| switch (mode) { |
| case RDT_MODE_SHAREABLE: |
| sw_shareable |= ctrl_val; |
| break; |
| case RDT_MODE_EXCLUSIVE: |
| exclusive |= ctrl_val; |
| break; |
| case RDT_MODE_PSEUDO_LOCKSETUP: |
| /* |
| * RDT_MODE_PSEUDO_LOCKSETUP is possible |
| * here but not included since the CBM |
| * associated with this CLOSID in this mode |
| * is not initialized and no task or cpu can be |
| * assigned this CLOSID. |
| */ |
| break; |
| case RDT_MODE_PSEUDO_LOCKED: |
| case RDT_NUM_MODES: |
| WARN(1, |
| "invalid mode for closid %d\n", i); |
| break; |
| } |
| } |
| for (i = r->cache.cbm_len - 1; i >= 0; i--) { |
| pseudo_locked = dom->plr ? dom->plr->cbm : 0; |
| hwb = test_bit(i, &hw_shareable); |
| swb = test_bit(i, &sw_shareable); |
| excl = test_bit(i, &exclusive); |
| psl = test_bit(i, &pseudo_locked); |
| if (hwb && swb) |
| seq_putc(seq, 'X'); |
| else if (hwb && !swb) |
| seq_putc(seq, 'H'); |
| else if (!hwb && swb) |
| seq_putc(seq, 'S'); |
| else if (excl) |
| seq_putc(seq, 'E'); |
| else if (psl) |
| seq_putc(seq, 'P'); |
| else /* Unused bits remain */ |
| seq_putc(seq, '0'); |
| } |
| sep = true; |
| } |
| seq_putc(seq, '\n'); |
| mutex_unlock(&rdtgroup_mutex); |
| return 0; |
| } |
| |
| static int rdt_min_bw_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| seq_printf(seq, "%u\n", r->membw.min_bw); |
| return 0; |
| } |
| |
| static int rdt_num_rmids_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_rmid); |
| |
| return 0; |
| } |
| |
| static int rdt_mon_features_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct rdt_resource *r = of->kn->parent->priv; |
| struct mon_evt *mevt; |
| |
| list_for_each_entry(mevt, &r->evt_list, list) |
| seq_printf(seq, "%s\n", mevt->name); |
| |
| return 0; |
| } |
| |
| static int rdt_bw_gran_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| seq_printf(seq, "%u\n", r->membw.bw_gran); |
| return 0; |
| } |
| |
| static int rdt_delay_linear_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| seq_printf(seq, "%u\n", r->membw.delay_linear); |
| return 0; |
| } |
| |
| static int max_threshold_occ_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| seq_printf(seq, "%u\n", resctrl_rmid_realloc_threshold); |
| |
| return 0; |
| } |
| |
| static int rdt_thread_throttle_mode_show(struct kernfs_open_file *of, |
| struct seq_file *seq, void *v) |
| { |
| struct resctrl_schema *s = of->kn->parent->priv; |
| struct rdt_resource *r = s->res; |
| |
| if (r->membw.throttle_mode == THREAD_THROTTLE_PER_THREAD) |
| seq_puts(seq, "per-thread\n"); |
| else |
| seq_puts(seq, "max\n"); |
| |
| return 0; |
| } |
| |
| static ssize_t max_threshold_occ_write(struct kernfs_open_file *of, |
| char *buf, size_t nbytes, loff_t off) |
| { |
| unsigned int bytes; |
| int ret; |
| |
| ret = kstrtouint(buf, 0, &bytes); |
| if (ret) |
| return ret; |
| |
| if (bytes > resctrl_rmid_realloc_limit) |
| return -EINVAL; |
| |
| resctrl_rmid_realloc_threshold = resctrl_arch_round_mon_val(bytes); |
| |
| return nbytes; |
| } |
| |
| /* |
| * rdtgroup_mode_show - Display mode of this resource group |
| */ |
| static int rdtgroup_mode_show(struct kernfs_open_file *of, |
| struct seq_file *s, void *v) |
| { |
| struct rdtgroup *rdtgrp; |
| |
| rdtgrp = rdtgroup_kn_lock_live(of->kn); |
| if (!rdtgrp) { |
| rdtgroup_kn_unlock(of->kn); |
| return -ENOENT; |
| } |
| |
| seq_printf(s, "%s\n", rdtgroup_mode_str(rdtgrp->mode)); |
| |
| rdtgroup_kn_unlock(of->kn); |
| return 0; |
| } |
| |
| static enum resctrl_conf_type resctrl_peer_type(enum resctrl_conf_type my_type) |
| { |
| switch (my_type) { |
| case CDP_CODE: |
| return CDP_DATA; |
| case CDP_DATA: |
| return CDP_CODE; |
| default: |
| case CDP_NONE: |
| return CDP_NONE; |
| } |
| } |
| |
| /** |
| * __rdtgroup_cbm_overlaps - Does CBM for intended closid overlap with other |
| * @r: Resource to which domain instance @d belongs. |
| * @d: The domain instance for which @closid is being tested. |
| * @cbm: Capacity bitmask being tested. |
| * @closid: Intended closid for @cbm. |
| * @exclusive: Only check if overlaps with exclusive resource groups |
| * |
| * Checks if provided @cbm intended to be used for @closid on domain |
| * @d overlaps with any other closids or other hardware usage associated |
| * with this domain. If @exclusive is true then only overlaps with |
| * resource groups in exclusive mode will be considered. If @exclusive |
| * is false then overlaps with any resource group or hardware entities |
| * will be considered. |
| * |
| * @cbm is unsigned long, even if only 32 bits are used, to make the |
| * bitmap functions work correctly. |
| * |
| * Return: false if CBM does not overlap, true if it does. |
| */ |
| static bool __rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d, |
| unsigned long cbm, int closid, |
| enum resctrl_conf_type type, bool exclusive) |
| { |
| enum rdtgrp_mode mode; |
| unsigned long ctrl_b; |
| int i; |
| |
| /* Check for any overlap with regions used by hardware directly */ |
| if (!exclusive) { |
| ctrl_b = r->cache.shareable_bits; |
| if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len)) |
| return true; |
| } |
| |
| /* Check for overlap with other resource groups */ |
| for (i = 0; i < closids_supported(); i++) { |
| ctrl_b = resctrl_arch_get_config(r, d, i, type); |
| mode = rdtgroup_mode_by_closid(i); |
| if (closid_allocated(i) && i != closid && |
| mode != RDT_MODE_PSEUDO_LOCKSETUP) { |
| if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len)) { |
| if (exclusive) { |
| if (mode == RDT_MODE_EXCLUSIVE) |
| return true; |
| continue; |
| } |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * rdtgroup_cbm_overlaps - Does CBM overlap with other use of hardware |
| * @s: Schema for the resource to which domain instance @d belongs. |
| * @d: The domain instance for which @closid is being tested. |
| * @cbm: Capacity bitmask being tested. |
| * @closid: Intended closid for @cbm. |
| * @exclusive: Only check if overlaps with exclusive resource groups |
| * |
| * Resources that can be allocated using a CBM can use the CBM to control |
| * the overlap of these allocations. rdtgroup_cmb_overlaps() is the test |
| * for overlap. Overlap test is not limited to the specific resource for |
| * which the CBM is intended though - when dealing with CDP resources that |
| * share the underlying hardware the overlap check should be performed on |
| * the CDP resource sharing the hardware also. |
| * |
| * Refer to description of __rdtgroup_cbm_overlaps() for the details of the |
| * overlap test. |
| * |
| * Return: true if CBM overlap detected, false if there is no overlap |
| */ |
| bool rdtgroup_cbm_overlaps(struct resctrl_schema *s, struct rdt_domain *d, |
| unsigned long cbm, int closid, bool exclusive) |
| { |
| enum resctrl_conf_type peer_type = resctrl_peer_type(s->conf_type); |
| struct rdt_resource *r = s->res; |
| |
| if (__rdtgroup_cbm_overlaps(r, d, cbm, closid, s->conf_type, |
| exclusive)) |
| return true; |
| |
| if (!resctrl_arch_get_cdp_enabled(r->rid)) |
| return false; |
| return __rdtgroup_cbm_overlaps(r, d, cbm, closid, peer_type, exclusive); |
| } |
| |
| /** |
| * rdtgroup_mode_test_exclusive - Test if this resource group can be exclusive |
| * |
| * An exclusive resource group implies that there should be no sharing of |
| * its allocated resources. At the time this group is considered to be |
| * exclusive this test can determine if its current schemata supports this |
| * setting by testing for overlap with all other resource groups. |
| * |
| * Return: true if resource group can be exclusive, false if there is overlap |
| * with allocations of other resource groups and thus this resource group |
| * cannot be exclusive. |
| */ |
| static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp) |
| { |
| int closid = rdtgrp->closid; |
| struct resctrl_schema *s; |
| struct rdt_resource *r; |
| bool has_cache = false; |
| struct rdt_domain *d; |
| u32 ctrl; |
| |
| list_for_each_entry(s, &resctrl_schema_all, list) { |
| r = s->res; |
| if (r->rid == RDT_RESOURCE_MBA) |
| continue; |
| has_cache = true; |
| list_for_each_entry(d, &r->domains, list) { |
| ctrl = resctrl_arch_get_config(r, d, closid, |
| s->conf_type); |
| if (rdtgroup_cbm_overlaps(s, d, ctrl, closid, false)) { |
| rdt_last_cmd_puts("Schemata overlaps\n"); |
| return false; |
| } |
| } |
| } |
| |
| if (!has_cache) { |
| rdt_last_cmd_puts("Cannot be exclusive without CAT/CDP\n"); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /** |
| * rdtgroup_mode_write - Modify the resource group's mode |
| * |
| */ |
| static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of, |
| char *buf, size_t nbytes, loff_t off) |
| { |
| struct rdtgroup *rdtgrp; |
| enum rdtgrp_mode mode; |
| int ret = 0; |
| |
| /* 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; |
| } |
| |
| rdt_last_cmd_clear(); |
| |
| mode = rdtgrp->mode; |
| |
| if ((!strcmp(buf, "shareable") && mode == RDT_MODE_SHAREABLE) || |
| (!strcmp(buf, "exclusive") && mode == RDT_MODE_EXCLUSIVE) || |
| (!strcmp(buf, "pseudo-locksetup") && |
| mode == RDT_MODE_PSEUDO_LOCKSETUP) || |
| (!strcmp(buf, "pseudo-locked") && mode == RDT_MODE_PSEUDO_LOCKED)) |
| goto out; |
| |
| if (mode == RDT_MODE_PSEUDO_LOCKED) { |
| rdt_last_cmd_puts("Cannot change pseudo-locked group\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (!strcmp(buf, "shareable")) { |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { |
| ret = rdtgroup_locksetup_exit(rdtgrp); |
| if (ret) |
| goto out; |
| } |
| rdtgrp->mode = RDT_MODE_SHAREABLE; |
| } else if (!strcmp(buf, "exclusive")) { |
| if (!rdtgroup_mode_test_exclusive(rdtgrp)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { |
| ret = rdtgroup_locksetup_exit(rdtgrp); |
| if (ret) |
| goto out; |
| } |
| rdtgrp->mode = RDT_MODE_EXCLUSIVE; |
| } else if (!strcmp(buf, "pseudo-locksetup")) { |
| ret = rdtgroup_locksetup_enter(rdtgrp); |
| if (ret) |
| goto out; |
| rdtgrp->mode = RDT_MODE_PSEUDO_LOCKSETUP; |
| } else { |
| rdt_last_cmd_puts("Unknown or unsupported mode\n"); |
| ret = -EINVAL; |
| } |
| |
| out: |
| rdtgroup_kn_unlock(of->kn); |
| return ret ?: nbytes; |
| } |
| |
| /** |
| * rdtgroup_cbm_to_size - Translate CBM to size in bytes |
| * @r: RDT resource to which @d belongs. |
| * @d: RDT domain instance. |
| * @cbm: bitmask for which the size should be computed. |
| * |
| * The bitmask provided associated with the RDT domain instance @d will be |
| * translated into how many bytes it represents. The size in bytes is |
| * computed by first dividing the total cache size by the CBM length to |
| * determine how many bytes each bit in the bitmask represents. The result |
| * is multiplied with the number of bits set in the bitmask. |
| * |
| * @cbm is unsigned long, even if only 32 bits are used to make the |
| * bitmap functions work correctly. |
| */ |
| unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, |
| struct rdt_domain *d, unsigned long cbm) |
| { |
| struct cpu_cacheinfo *ci; |
| unsigned int size = 0; |
| int num_b, i; |
| |
| num_b = bitmap_weight(&cbm, r->cache.cbm_len); |
| ci = get_cpu_cacheinfo(cpumask_any(&d->cpu_mask)); |
| for (i = 0; i < ci->num_leaves; i++) { |
| if (ci->info_list[i].level == r->cache_level) { |
| size = ci->info_list[i].size / r->cache.cbm_len * num_b; |
| break; |
| } |
| } |
| |
| return size; |
| } |
| |
| /** |
| * rdtgroup_size_show - Display size in bytes of allocated regions |
| * |
| * The "size" file mirrors the layout of the "schemata" file, printing the |
| * size in bytes of each region instead of the capacity bitmask. |
| * |
| */ |
| static int rdtgroup_size_show(struct kernfs_open_file *of, |
| struct seq_file *s, void *v) |
| { |
| struct resctrl_schema *schema; |
| enum resctrl_conf_type type; |
| struct rdtgroup *rdtgrp; |
| struct rdt_resource *r; |
| struct rdt_domain *d; |
| unsigned int size; |
| int ret = 0; |
| u32 closid; |
| bool sep; |
| u32 ctrl; |
| |
| rdtgrp = rdtgroup_kn_lock_live(of->kn); |
| if (!rdtgrp) { |
| rdtgroup_kn_unlock(of->kn); |
| return -ENOENT; |
| } |
| |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) { |
| if (!rdtgrp->plr->d) { |
| rdt_last_cmd_clear(); |
| rdt_last_cmd_puts("Cache domain offline\n"); |
| ret = -ENODEV; |
| } else { |
| seq_printf(s, "%*s:", max_name_width, |
| rdtgrp->plr->s->name); |
| size = rdtgroup_cbm_to_size(rdtgrp->plr->s->res, |
| rdtgrp->plr->d, |
| rdtgrp->plr->cbm); |
| seq_printf(s, "%d=%u\n", rdtgrp->plr->d->id, size); |
| } |
| goto out; |
| } |
| |
| closid = rdtgrp->closid; |
| |
| list_for_each_entry(schema, &resctrl_schema_all, list) { |
| r = schema->res; |
| type = schema->conf_type; |
| sep = false; |
| seq_printf(s, "%*s:", max_name_width, schema->name); |
| list_for_each_entry(d, &r->domains, list) { |
| if (sep) |
| seq_putc(s, ';'); |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { |
| size = 0; |
| } else { |
| if (is_mba_sc(r)) |
| ctrl = d->mbps_val[closid]; |
| else |
| ctrl = resctrl_arch_get_config(r, d, |
| closid, |
| type); |
| if (r->rid == RDT_RESOURCE_MBA) |
| size = ctrl; |
| else |
| size = rdtgroup_cbm_to_size(r, d, ctrl); |
| } |
| seq_printf(s, "%d=%u", d->id, size); |
| sep = true; |
| } |
| seq_putc(s, '\n'); |
| } |
| |
| out: |
| rdtgroup_kn_unlock(of->kn); |
| |
| return ret; |
| } |
| |
| /* rdtgroup information files for one cache resource. */ |
| static struct rftype res_common_files[] = { |
| { |
| .name = "last_cmd_status", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_last_cmd_status_show, |
| .fflags = RF_TOP_INFO, |
| }, |
| { |
| .name = "num_closids", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_num_closids_show, |
| .fflags = RF_CTRL_INFO, |
| }, |
| { |
| .name = "mon_features", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_mon_features_show, |
| .fflags = RF_MON_INFO, |
| }, |
| { |
| .name = "num_rmids", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_num_rmids_show, |
| .fflags = RF_MON_INFO, |
| }, |
| { |
| .name = "cbm_mask", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_default_ctrl_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE, |
| }, |
| { |
| .name = "min_cbm_bits", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_min_cbm_bits_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE, |
| }, |
| { |
| .name = "shareable_bits", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_shareable_bits_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE, |
| }, |
| { |
| .name = "bit_usage", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_bit_usage_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE, |
| }, |
| { |
| .name = "min_bandwidth", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_min_bw_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_MB, |
| }, |
| { |
| .name = "bandwidth_gran", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_bw_gran_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_MB, |
| }, |
| { |
| .name = "delay_linear", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_delay_linear_show, |
| .fflags = RF_CTRL_INFO | RFTYPE_RES_MB, |
| }, |
| /* |
| * Platform specific which (if any) capabilities are provided by |
| * thread_throttle_mode. Defer "fflags" initialization to platform |
| * discovery. |
| */ |
| { |
| .name = "thread_throttle_mode", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdt_thread_throttle_mode_show, |
| }, |
| { |
| .name = "max_threshold_occupancy", |
| .mode = 0644, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .write = max_threshold_occ_write, |
| .seq_show = max_threshold_occ_show, |
| .fflags = RF_MON_INFO | RFTYPE_RES_CACHE, |
| }, |
| { |
| .name = "cpus", |
| .mode = 0644, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .write = rdtgroup_cpus_write, |
| .seq_show = rdtgroup_cpus_show, |
| .fflags = RFTYPE_BASE, |
| }, |
| { |
| .name = "cpus_list", |
| .mode = 0644, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .write = rdtgroup_cpus_write, |
| .seq_show = rdtgroup_cpus_show, |
| .flags = RFTYPE_FLAGS_CPUS_LIST, |
| .fflags = RFTYPE_BASE, |
| }, |
| { |
| .name = "tasks", |
| .mode = 0644, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .write = rdtgroup_tasks_write, |
| .seq_show = rdtgroup_tasks_show, |
| .fflags = RFTYPE_BASE, |
| }, |
| { |
| .name = "schemata", |
| .mode = 0644, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .write = rdtgroup_schemata_write, |
| .seq_show = rdtgroup_schemata_show, |
| .fflags = RF_CTRL_BASE, |
| }, |
| { |
| .name = "mode", |
| .mode = 0644, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .write = rdtgroup_mode_write, |
| .seq_show = rdtgroup_mode_show, |
| .fflags = RF_CTRL_BASE, |
| }, |
| { |
| .name = "size", |
| .mode = 0444, |
| .kf_ops = &rdtgroup_kf_single_ops, |
| .seq_show = rdtgroup_size_show, |
| .fflags = RF_CTRL_BASE, |
| }, |
| |
| }; |
| |
| static int rdtgroup_add_files(struct kernfs_node *kn, unsigned long fflags) |
| { |
| struct rftype *rfts, *rft; |
| int ret, len; |
| |
| rfts = res_common_files; |
| len = ARRAY_SIZE(res_common_files); |
| |
| lockdep_assert_held(&rdtgroup_mutex); |
| |
| for (rft = rfts; rft < rfts + len; rft++) { |
| if (rft->fflags && ((fflags & rft->fflags) == rft->fflags)) { |
| 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) { |
| if ((fflags & rft->fflags) == rft->fflags) |
| kernfs_remove_by_name(kn, rft->name); |
| } |
| return ret; |
| } |
| |
| static struct rftype *rdtgroup_get_rftype_by_name(const char *name) |
| { |
| struct rftype *rfts, *rft; |
| int len; |
| |
| rfts = res_common_files; |
| len = ARRAY_SIZE(res_common_files); |
| |
| for (rft = rfts; rft < rfts + len; rft++) { |
| if (!strcmp(rft->name, name)) |
| return rft; |
| } |
| |
| return NULL; |
| } |
| |
| void __init thread_throttle_mode_init(void) |
| { |
| struct rftype *rft; |
| |
| rft = rdtgroup_get_rftype_by_name("thread_throttle_mode"); |
| if (!rft) |
| return; |
| |
| rft->fflags = RF_CTRL_INFO | RFTYPE_RES_MB; |
| } |
| |
| /** |
| * rdtgroup_kn_mode_restrict - Restrict user access to named resctrl file |
| * @r: The resource group with which the file is associated. |
| * @name: Name of the file |
| * |
| * The permissions of named resctrl file, directory, or link are modified |
| * to not allow read, write, or execute by any user. |
| * |
| * WARNING: This function is intended to communicate to the user that the |
| * resctrl file has been locked down - that it is not relevant to the |
| * particular state the system finds itself in. It should not be relied |
| * on to protect from user access because after the file's permissions |
| * are restricted the user can still change the permissions using chmod |
| * from the command line. |
| * |
| * Return: 0 on success, <0 on failure. |
| */ |
| int rdtgroup_kn_mode_restrict(struct rdtgroup *r, const char *name) |
| { |
| struct iattr iattr = {.ia_valid = ATTR_MODE,}; |
| struct kernfs_node *kn; |
| int ret = 0; |
| |
| kn = kernfs_find_and_get_ns(r->kn, name, NULL); |
| if (!kn) |
| return -ENOENT; |
| |
| switch (kernfs_type(kn)) { |
| case KERNFS_DIR: |
| iattr.ia_mode = S_IFDIR; |
| break; |
| case KERNFS_FILE: |
| iattr.ia_mode = S_IFREG; |
| break; |
| case KERNFS_LINK: |
| iattr.ia_mode = S_IFLNK; |
| break; |
| } |
| |
| ret = kernfs_setattr(kn, &iattr); |
| kernfs_put(kn); |
| return ret; |
| } |
| |
| /** |
| * rdtgroup_kn_mode_restore - Restore user access to named resctrl file |
| * @r: The resource group with which the file is associated. |
| * @name: Name of the file |
| * @mask: Mask of permissions that should be restored |
| * |
| * Restore the permissions of the named file. If @name is a directory the |
| * permissions of its parent will be used. |
| * |
| * Return: 0 on success, <0 on failure. |
| */ |
| int rdtgroup_kn_mode_restore(struct rdtgroup *r, const char *name, |
| umode_t mask) |
| { |
| struct iattr iattr = {.ia_valid = ATTR_MODE,}; |
| struct kernfs_node *kn, *parent; |
| struct rftype *rfts, *rft; |
| int ret, len; |
| |
| rfts = res_common_files; |
| len = ARRAY_SIZE(res_common_files); |
| |
| for (rft = rfts; rft < rfts + len; rft++) { |
| if (!strcmp(rft->name, name)) |
| iattr.ia_mode = rft->mode & mask; |
| } |
| |
| kn = kernfs_find_and_get_ns(r->kn, name, NULL); |
| if (!kn) |
| return -ENOENT; |
| |
| switch (kernfs_type(kn)) { |
| case KERNFS_DIR: |
| parent = kernfs_get_parent(kn); |
| if (parent) { |
| iattr.ia_mode |= parent->mode; |
| kernfs_put(parent); |
| } |
| iattr.ia_mode |= S_IFDIR; |
| break; |
| case KERNFS_FILE: |
| iattr.ia_mode |= S_IFREG; |
| break; |
| case KERNFS_LINK: |
| iattr.ia_mode |= S_IFLNK; |
| break; |
| } |
| |
| ret = kernfs_setattr(kn, &iattr); |
| kernfs_put(kn); |
| return ret; |
| } |
| |
| static int rdtgroup_mkdir_info_resdir(void *priv, char *name, |
| unsigned long fflags) |
| { |
| struct kernfs_node *kn_subdir; |
| int ret; |
| |
| kn_subdir = kernfs_create_dir(kn_info, name, |
| kn_info->mode, priv); |
| if (IS_ERR(kn_subdir)) |
| return PTR_ERR(kn_subdir); |
| |
| ret = rdtgroup_kn_set_ugid(kn_subdir); |
| if (ret) |
| return ret; |
| |
| ret = rdtgroup_add_files(kn_subdir, fflags); |
| if (!ret) |
| kernfs_activate(kn_subdir); |
| |
| return ret; |
| } |
| |
| static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn) |
| { |
| struct resctrl_schema *s; |
| struct rdt_resource *r; |
| unsigned long fflags; |
| char name[32]; |
| 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); |
| |
| ret = rdtgroup_add_files(kn_info, RF_TOP_INFO); |
| if (ret) |
| goto out_destroy; |
| |
| /* loop over enabled controls, these are all alloc_capable */ |
| list_for_each_entry(s, &resctrl_schema_all, list) { |
| r = s->res; |
| fflags = r->fflags | RF_CTRL_INFO; |
| ret = rdtgroup_mkdir_info_resdir(s, s->name, fflags); |
| if (ret) |
| goto out_destroy; |
| } |
| |
| for_each_mon_capable_rdt_resource(r) { |
| fflags = r->fflags | RF_MON_INFO; |
| sprintf(name, "%s_MON", r->name); |
| ret = rdtgroup_mkdir_info_resdir(r, name, fflags); |
| if (ret) |
| goto out_destroy; |
| } |
| |
| 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 int |
| mongroup_create_dir(struct kernfs_node *parent_kn, struct rdtgroup *prgrp, |
| char *name, struct kernfs_node **dest_kn) |
| { |
| struct kernfs_node *kn; |
| int ret; |
| |
| /* create the directory */ |
| kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp); |
| if (IS_ERR(kn)) |
| return PTR_ERR(kn); |
| |
| if (dest_kn) |
| *dest_kn = kn; |
| |
| ret = rdtgroup_kn_set_ugid(kn); |
| if (ret) |
| goto out_destroy; |
| |
| kernfs_activate(kn); |
| |
| return 0; |
| |
| out_destroy: |
| kernfs_remove(kn); |
| return ret; |
| } |
| |
| static void l3_qos_cfg_update(void *arg) |
| { |
| bool *enable = arg; |
| |
| wrmsrl(MSR_IA32_L3_QOS_CFG, *enable ? L3_QOS_CDP_ENABLE : 0ULL); |
| } |
| |
| static void l2_qos_cfg_update(void *arg) |
| { |
| bool *enable = arg; |
| |
| wrmsrl(MSR_IA32_L2_QOS_CFG, *enable ? L2_QOS_CDP_ENABLE : 0ULL); |
| } |
| |
| static inline bool is_mba_linear(void) |
| { |
| return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.delay_linear; |
| } |
| |
| static int set_cache_qos_cfg(int level, bool enable) |
| { |
| void (*update)(void *arg); |
| struct rdt_resource *r_l; |
| cpumask_var_t cpu_mask; |
| struct rdt_domain *d; |
| int cpu; |
| |
| if (level == RDT_RESOURCE_L3) |
| update = l3_qos_cfg_update; |
| else if (level == RDT_RESOURCE_L2) |
| update = l2_qos_cfg_update; |
| else |
| return -EINVAL; |
| |
| if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL)) |
| return -ENOMEM; |
| |
| r_l = &rdt_resources_all[level].r_resctrl; |
| list_for_each_entry(d, &r_l->domains, list) { |
| if (r_l->cache.arch_has_per_cpu_cfg) |
| /* Pick all the CPUs in the domain instance */ |
| for_each_cpu(cpu, &d->cpu_mask) |
| cpumask_set_cpu(cpu, cpu_mask); |
| else |
| /* 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)) |
| update(&enable); |
| /* Update QOS_CFG MSR on all other cpus in cpu_mask. */ |
| smp_call_function_many(cpu_mask, update, &enable, 1); |
| put_cpu(); |
| |
| free_cpumask_var(cpu_mask); |
| |
| return 0; |
| } |
| |
| /* Restore the qos cfg state when a domain comes online */ |
| void rdt_domain_reconfigure_cdp(struct rdt_resource *r) |
| { |
| struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r); |
| |
| if (!r->cdp_capable) |
| return; |
| |
| if (r->rid == RDT_RESOURCE_L2) |
| l2_qos_cfg_update(&hw_res->cdp_enabled); |
| |
| if (r->rid == RDT_RESOURCE_L3) |
| l3_qos_cfg_update(&hw_res->cdp_enabled); |
| } |
| |
| static int mba_sc_domain_allocate(struct rdt_resource *r, struct rdt_domain *d) |
| { |
| u32 num_closid = resctrl_arch_get_num_closid(r); |
| int cpu = cpumask_any(&d->cpu_mask); |
| int i; |
| |
| d->mbps_val = kcalloc_node(num_closid, sizeof(*d->mbps_val), |
| GFP_KERNEL, cpu_to_node(cpu)); |
| if (!d->mbps_val) |
| return -ENOMEM; |
| |
| for (i = 0; i < num_closid; i++) |
| d->mbps_val[i] = MBA_MAX_MBPS; |
| |
| return 0; |
| } |
| |
| static void mba_sc_domain_destroy(struct rdt_resource *r, |
| struct rdt_domain *d) |
| { |
| kfree(d->mbps_val); |
| d->mbps_val = NULL; |
| } |
| |
| /* |
| * MBA software controller is supported only if |
| * MBM is supported and MBA is in linear scale. |
| */ |
| static bool supports_mba_mbps(void) |
| { |
| struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; |
| |
| return (is_mbm_local_enabled() && |
| r->alloc_capable && is_mba_linear()); |
| } |
| |
| /* |
| * Enable or disable the MBA software controller |
| * which helps user specify bandwidth in MBps. |
| */ |
| static int set_mba_sc(bool mba_sc) |
| { |
| struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; |
| u32 num_closid = resctrl_arch_get_num_closid(r); |
| struct rdt_domain *d; |
| int i; |
| |
| if (!supports_mba_mbps() || mba_sc == is_mba_sc(r)) |
| return -EINVAL; |
| |
| r->membw.mba_sc = mba_sc; |
| |
| list_for_each_entry(d, &r->domains, list) { |
| for (i = 0; i < num_closid; i++) |
| d->mbps_val[i] = MBA_MAX_MBPS; |
| } |
| |
| return 0; |
| } |
| |
| static int cdp_enable(int level) |
| { |
| struct rdt_resource *r_l = &rdt_resources_all[level].r_resctrl; |
| int ret; |
| |
| if (!r_l->alloc_capable) |
| return -EINVAL; |
| |
| ret = set_cache_qos_cfg(level, true); |
| if (!ret) |
| rdt_resources_all[level].cdp_enabled = true; |
| |
| return ret; |
| } |
| |
| static void cdp_disable(int level) |
| { |
| struct rdt_hw_resource *r_hw = &rdt_resources_all[level]; |
| |
| if (r_hw->cdp_enabled) { |
| set_cache_qos_cfg(level, false); |
| r_hw->cdp_enabled = false; |
| } |
| } |
| |
| int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable) |
| { |
| struct rdt_hw_resource *hw_res = &rdt_resources_all[l]; |
| |
| if (!hw_res->r_resctrl.cdp_capable) |
| return -EINVAL; |
| |
| if (enable) |
| return cdp_enable(l); |
| |
| cdp_disable(l); |
| |
| return 0; |
| } |
| |
| static void cdp_disable_all(void) |
| { |
| if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3)) |
| resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false); |
| if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2)) |
| resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false); |
| } |
| |
| /* |
| * 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)) { |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP || |
| rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) |
| rdtgroup_pseudo_lock_remove(rdtgrp); |
| kernfs_unbreak_active_protection(kn); |
| rdtgroup_remove(rdtgrp); |
| } else { |
| kernfs_unbreak_active_protection(kn); |
| } |
| } |
| |
| static int mkdir_mondata_all(struct kernfs_node *parent_kn, |
| struct rdtgroup *prgrp, |
| struct kernfs_node **mon_data_kn); |
| |
| static int rdt_enable_ctx(struct rdt_fs_context *ctx) |
| { |
| int ret = 0; |
| |
| if (ctx->enable_cdpl2) |
| ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, true); |
| |
| if (!ret && ctx->enable_cdpl3) |
| ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, true); |
| |
| if (!ret && ctx->enable_mba_mbps) |
| ret = set_mba_sc(true); |
| |
| return ret; |
| } |
| |
| static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type) |
| { |
| struct resctrl_schema *s; |
| const char *suffix = ""; |
| int ret, cl; |
| |
| s = kzalloc(sizeof(*s), GFP_KERNEL); |
| if (!s) |
| return -ENOMEM; |
| |
| s->res = r; |
| s->num_closid = resctrl_arch_get_num_closid(r); |
| if (resctrl_arch_get_cdp_enabled(r->rid)) |
| s->num_closid /= 2; |
| |
| s->conf_type = type; |
| switch (type) { |
| case CDP_CODE: |
| suffix = "CODE"; |
| break; |
| case CDP_DATA: |
| suffix = "DATA"; |
| break; |
| case CDP_NONE: |
| suffix = ""; |
| break; |
| } |
| |
| ret = snprintf(s->name, sizeof(s->name), "%s%s", r->name, suffix); |
| if (ret >= sizeof(s->name)) { |
| kfree(s); |
| return -EINVAL; |
| } |
| |
| cl = strlen(s->name); |
| |
| /* |
| * If CDP is supported by this resource, but not enabled, |
| * include the suffix. This ensures the tabular format of the |
| * schemata file does not change between mounts of the filesystem. |
| */ |
| if (r->cdp_capable && !resctrl_arch_get_cdp_enabled(r->rid)) |
| cl += 4; |
| |
| if (cl > max_name_width) |
| max_name_width = cl; |
| |
| INIT_LIST_HEAD(&s->list); |
| list_add(&s->list, &resctrl_schema_all); |
| |
| return 0; |
| } |
| |
| static int schemata_list_create(void) |
| { |
| struct rdt_resource *r; |
| int ret = 0; |
| |
| for_each_alloc_capable_rdt_resource(r) { |
| if (resctrl_arch_get_cdp_enabled(r->rid)) { |
| ret = schemata_list_add(r, CDP_CODE); |
| if (ret) |
| break; |
| |
| ret = schemata_list_add(r, CDP_DATA); |
| } else { |
| ret = schemata_list_add(r, CDP_NONE); |
| } |
| |
| if (ret) |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static void schemata_list_destroy(void) |
| { |
| struct resctrl_schema *s, *tmp; |
| |
| list_for_each_entry_safe(s, tmp, &resctrl_schema_all, list) { |
| list_del(&s->list); |
| kfree(s); |
| } |
| } |
| |
| static int rdt_get_tree(struct fs_context *fc) |
| { |
| struct rdt_fs_context *ctx = rdt_fc2context(fc); |
| struct rdt_domain *dom; |
| struct rdt_resource *r; |
| int ret; |
| |
| cpus_read_lock(); |
| mutex_lock(&rdtgroup_mutex); |
| /* |
| * resctrl file system can only be mounted once. |
| */ |
| if (static_branch_unlikely(&rdt_enable_key)) { |
| ret = -EBUSY; |
| goto out; |
| } |
| |
| ret = rdt_enable_ctx(ctx); |
| if (ret < 0) |
| goto out_cdp; |
| |
| ret = schemata_list_create(); |
| if (ret) { |
| schemata_list_destroy(); |
| goto out_mba; |
| } |
| |
| closid_init(); |
| |
| ret = rdtgroup_create_info_dir(rdtgroup_default.kn); |
| if (ret < 0) |
| goto out_schemata_free; |
| |
| if (rdt_mon_capable) { |
| ret = mongroup_create_dir(rdtgroup_default.kn, |
| &rdtgroup_default, "mon_groups", |
| &kn_mongrp); |
| if (ret < 0) |
| goto out_info; |
| |
| ret = mkdir_mondata_all(rdtgroup_default.kn, |
| &rdtgroup_default, &kn_mondata); |
| if (ret < 0) |
| goto out_mongrp; |
| rdtgroup_default.mon.mon_data_kn = kn_mondata; |
| } |
| |
| ret = rdt_pseudo_lock_init(); |
| if (ret) |
| goto out_mondata; |
| |
| ret = kernfs_get_tree(fc); |
| if (ret < 0) |
| goto out_psl; |
| |
| if (rdt_alloc_capable) |
| static_branch_enable_cpuslocked(&rdt_alloc_enable_key); |
| if (rdt_mon_capable) |
| static_branch_enable_cpuslocked(&rdt_mon_enable_key); |
| |
| if (rdt_alloc_capable || rdt_mon_capable) |
| static_branch_enable_cpuslocked(&rdt_enable_key); |
| |
| if (is_mbm_enabled()) { |
| r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; |
| list_for_each_entry(dom, &r->domains, list) |
| mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL); |
| } |
| |
| goto out; |
| |
| out_psl: |
| rdt_pseudo_lock_release(); |
| out_mondata: |
| if (rdt_mon_capable) |
| kernfs_remove(kn_mondata); |
| out_mongrp: |
| if (rdt_mon_capable) |
| kernfs_remove(kn_mongrp); |
| out_info: |
| kernfs_remove(kn_info); |
| out_schemata_free: |
| schemata_list_destroy(); |
| out_mba: |
| if (ctx->enable_mba_mbps) |
| set_mba_sc(false); |
| out_cdp: |
| cdp_disable_all(); |
| out: |
| rdt_last_cmd_clear(); |
| mutex_unlock(&rdtgroup_mutex); |
| cpus_read_unlock(); |
| return ret; |
| } |
| |
| enum rdt_param { |
| Opt_cdp, |
| Opt_cdpl2, |
| Opt_mba_mbps, |
| nr__rdt_params |
| }; |
| |
| static const struct fs_parameter_spec rdt_fs_parameters[] = { |
| fsparam_flag("cdp", Opt_cdp), |
| fsparam_flag("cdpl2", Opt_cdpl2), |
| fsparam_flag("mba_MBps", Opt_mba_mbps), |
| {} |
| }; |
| |
| static int rdt_parse_param(struct fs_context *fc, struct fs_parameter *param) |
| { |
| struct rdt_fs_context *ctx = rdt_fc2context(fc); |
| struct fs_parse_result result; |
| int opt; |
| |
| opt = fs_parse(fc, rdt_fs_parameters, param, &result); |
| if (opt < 0) |
| return opt; |
| |
| switch (opt) { |
| case Opt_cdp: |
| ctx->enable_cdpl3 = true; |
| return 0; |
| case Opt_cdpl2: |
| ctx->enable_cdpl2 = true; |
| return 0; |
| case Opt_mba_mbps: |
| if (!supports_mba_mbps()) |
| return -EINVAL; |
| ctx->enable_mba_mbps = true; |
| return 0; |
| } |
| |
| return -EINVAL; |
| } |
| |
| static void rdt_fs_context_free(struct fs_context *fc) |
| { |
| struct rdt_fs_context *ctx = rdt_fc2context(fc); |
| |
| kernfs_free_fs_context(fc); |
| kfree(ctx); |
| } |
| |
| static const struct fs_context_operations rdt_fs_context_ops = { |
| .free = rdt_fs_context_free, |
| .parse_param = rdt_parse_param, |
| .get_tree = rdt_get_tree, |
| }; |
| |
| static int rdt_init_fs_context(struct fs_context *fc) |
| { |
| struct rdt_fs_context *ctx; |
| |
| ctx = kzalloc(sizeof(struct rdt_fs_context), GFP_KERNEL); |
| if (!ctx) |
| return -ENOMEM; |
| |
| ctx->kfc.root = rdt_root; |
| ctx->kfc.magic = RDTGROUP_SUPER_MAGIC; |
| fc->fs_private = &ctx->kfc; |
| fc->ops = &rdt_fs_context_ops; |
| put_user_ns(fc->user_ns); |
| fc->user_ns = get_user_ns(&init_user_ns); |
| fc->global = true; |
| return 0; |
| } |
| |
| static int reset_all_ctrls(struct rdt_resource *r) |
| { |
| struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r); |
| struct rdt_hw_domain *hw_dom; |
| 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 = hw_res->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) { |
| hw_dom = resctrl_to_arch_dom(d); |
| cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask); |
| |
| for (i = 0; i < hw_res->num_closid; i++) |
| hw_dom->ctrl_val[i] = r->default_ctrl; |
| } |
| cpu = get_cpu(); |
| /* Update CBM on this cpu if it's in cpu_mask. */ |
| if (cpumask_test_cpu(cpu, cpu_mask)) |
| rdt_ctrl_update(&msr_param); |
| /* Update CBM on all other cpus in cpu_mask. */ |
| smp_call_function_many(cpu_mask, rdt_ctrl_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 || is_closid_match(t, from) || |
| is_rmid_match(t, from)) { |
| WRITE_ONCE(t->closid, to->closid); |
| WRITE_ONCE(t->rmid, to->mon.rmid); |
| |
| /* |
| * Order the closid/rmid stores above before the loads |
| * in task_curr(). This pairs with the full barrier |
| * between the rq->curr update and resctrl_sched_in() |
| * during context switch. |
| */ |
| smp_mb(); |
| |
| /* |
| * If the task is on a CPU, set the CPU in the mask. |
| * 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 (IS_ENABLED(CONFIG_SMP) && mask && task_curr(t)) |
| cpumask_set_cpu(task_cpu(t), mask); |
| } |
| } |
| read_unlock(&tasklist_lock); |
| } |
| |
| static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp) |
| { |
| struct rdtgroup *sentry, *stmp; |
| struct list_head *head; |
| |
| head = &rdtgrp->mon.crdtgrp_list; |
| list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) { |
| free_rmid(sentry->mon.rmid); |
| list_del(&sentry->mon.crdtgrp_list); |
| |
| if (atomic_read(&sentry->waitcount) != 0) |
| sentry->flags = RDT_DELETED; |
| else |
| rdtgroup_remove(sentry); |
| } |
| } |
| |
| /* |
| * 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) { |
| /* Free any child rmids */ |
| free_all_child_rdtgrp(rdtgrp); |
| |
| /* Remove each rdtgroup other than root */ |
| if (rdtgrp == &rdtgroup_default) |
| continue; |
| |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP || |
| rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) |
| rdtgroup_pseudo_lock_remove(rdtgrp); |
| |
| /* |
| * 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); |
| |
| free_rmid(rdtgrp->mon.rmid); |
| |
| kernfs_remove(rdtgrp->kn); |
| list_del(&rdtgrp->rdtgroup_list); |
| |
| if (atomic_read(&rdtgrp->waitcount) != 0) |
| rdtgrp->flags = RDT_DELETED; |
| else |
| rdtgroup_remove(rdtgrp); |
| } |
| /* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */ |
| update_closid_rmid(cpu_online_mask, &rdtgroup_default); |
| |
| kernfs_remove(kn_info); |
| kernfs_remove(kn_mongrp); |
| kernfs_remove(kn_mondata); |
| } |
| |
| static void rdt_kill_sb(struct super_block *sb) |
| { |
| struct rdt_resource *r; |
| |
| cpus_read_lock(); |
| mutex_lock(&rdtgroup_mutex); |
| |
| set_mba_sc(false); |
| |
| /*Put everything back to default values. */ |
| for_each_alloc_capable_rdt_resource(r) |
| reset_all_ctrls(r); |
| cdp_disable_all(); |
| rmdir_all_sub(); |
| rdt_pseudo_lock_release(); |
| rdtgroup_default.mode = RDT_MODE_SHAREABLE; |
| schemata_list_destroy(); |
| static_branch_disable_cpuslocked(&rdt_alloc_enable_key); |
| static_branch_disable_cpuslocked(&rdt_mon_enable_key); |
| static_branch_disable_cpuslocked(&rdt_enable_key); |
| kernfs_kill_sb(sb); |
| mutex_unlock(&rdtgroup_mutex); |
| cpus_read_unlock(); |
| } |
| |
| static struct file_system_type rdt_fs_type = { |
| .name = "resctrl", |
| .init_fs_context = rdt_init_fs_context, |
| .parameters = rdt_fs_parameters, |
| .kill_sb = rdt_kill_sb, |
| }; |
| |
| static int mon_addfile(struct kernfs_node *parent_kn, const char *name, |
| void *priv) |
| { |
| struct kernfs_node *kn; |
| int ret = 0; |
| |
| kn = __kernfs_create_file(parent_kn, name, 0444, |
| GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, 0, |
| &kf_mondata_ops, priv, NULL, NULL); |
| if (IS_ERR(kn)) |
| return PTR_ERR(kn); |
| |
| ret = rdtgroup_kn_set_ugid(kn); |
| if (ret) { |
| kernfs_remove(kn); |
| return ret; |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * Remove all subdirectories of mon_data of ctrl_mon groups |
| * and monitor groups with given domain id. |
| */ |
| static void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r, |
| unsigned int dom_id) |
| { |
| struct rdtgroup *prgrp, *crgrp; |
| char name[32]; |
| |
| list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) { |
| sprintf(name, "mon_%s_%02d", r->name, dom_id); |
| kernfs_remove_by_name(prgrp->mon.mon_data_kn, name); |
| |
| list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list) |
| kernfs_remove_by_name(crgrp->mon.mon_data_kn, name); |
| } |
| } |
| |
| static int mkdir_mondata_subdir(struct kernfs_node *parent_kn, |
| struct rdt_domain *d, |
| struct rdt_resource *r, struct rdtgroup *prgrp) |
| { |
| union mon_data_bits priv; |
| struct kernfs_node *kn; |
| struct mon_evt *mevt; |
| struct rmid_read rr; |
| char name[32]; |
| int ret; |
| |
| sprintf(name, "mon_%s_%02d", r->name, d->id); |
| /* create the directory */ |
| kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp); |
| if (IS_ERR(kn)) |
| return PTR_ERR(kn); |
| |
| ret = rdtgroup_kn_set_ugid(kn); |
| if (ret) |
| goto out_destroy; |
| |
| if (WARN_ON(list_empty(&r->evt_list))) { |
| ret = -EPERM; |
| goto out_destroy; |
| } |
| |
| priv.u.rid = r->rid; |
| priv.u.domid = d->id; |
| list_for_each_entry(mevt, &r->evt_list, list) { |
| priv.u.evtid = mevt->evtid; |
| ret = mon_addfile(kn, mevt->name, priv.priv); |
| if (ret) |
| goto out_destroy; |
| |
| if (is_mbm_event(mevt->evtid)) |
| mon_event_read(&rr, r, d, prgrp, mevt->evtid, true); |
| } |
| kernfs_activate(kn); |
| return 0; |
| |
| out_destroy: |
| kernfs_remove(kn); |
| return ret; |
| } |
| |
| /* |
| * Add all subdirectories of mon_data for "ctrl_mon" groups |
| * and "monitor" groups with given domain id. |
| */ |
| static void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r, |
| struct rdt_domain *d) |
| { |
| struct kernfs_node *parent_kn; |
| struct rdtgroup *prgrp, *crgrp; |
| struct list_head *head; |
| |
| list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) { |
| parent_kn = prgrp->mon.mon_data_kn; |
| mkdir_mondata_subdir(parent_kn, d, r, prgrp); |
| |
| head = &prgrp->mon.crdtgrp_list; |
| list_for_each_entry(crgrp, head, mon.crdtgrp_list) { |
| parent_kn = crgrp->mon.mon_data_kn; |
| mkdir_mondata_subdir(parent_kn, d, r, crgrp); |
| } |
| } |
| } |
| |
| static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn, |
| struct rdt_resource *r, |
| struct rdtgroup *prgrp) |
| { |
| struct rdt_domain *dom; |
| int ret; |
| |
| list_for_each_entry(dom, &r->domains, list) { |
| ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * This creates a directory mon_data which contains the monitored data. |
| * |
| * mon_data has one directory for each domain which are named |
| * in the format mon_<domain_name>_<domain_id>. For ex: A mon_data |
| * with L3 domain looks as below: |
| * ./mon_data: |
| * mon_L3_00 |
| * mon_L3_01 |
| * mon_L3_02 |
| * ... |
| * |
| * Each domain directory has one file per event: |
| * ./mon_L3_00/: |
| * llc_occupancy |
| * |
| */ |
| static int mkdir_mondata_all(struct kernfs_node *parent_kn, |
| struct rdtgroup *prgrp, |
| struct kernfs_node **dest_kn) |
| { |
| struct rdt_resource *r; |
| struct kernfs_node *kn; |
| int ret; |
| |
| /* |
| * Create the mon_data directory first. |
| */ |
| ret = mongroup_create_dir(parent_kn, prgrp, "mon_data", &kn); |
| if (ret) |
| return ret; |
| |
| if (dest_kn) |
| *dest_kn = kn; |
| |
| /* |
| * Create the subdirectories for each domain. Note that all events |
| * in a domain like L3 are grouped into a resource whose domain is L3 |
| */ |
| for_each_mon_capable_rdt_resource(r) { |
| ret = mkdir_mondata_subdir_alldom(kn, r, prgrp); |
| if (ret) |
| goto out_destroy; |
| } |
| |
| return 0; |
| |
| out_destroy: |
| kernfs_remove(kn); |
| return ret; |
| } |
| |
| /** |
| * cbm_ensure_valid - Enforce validity on provided CBM |
| * @_val: Candidate CBM |
| * @r: RDT resource to which the CBM belongs |
| * |
| * The provided CBM represents all cache portions available for use. This |
| * may be represented by a bitmap that does not consist of contiguous ones |
| * and thus be an invalid CBM. |
| * Here the provided CBM is forced to be a valid CBM by only considering |
| * the first set of contiguous bits as valid and clearing all bits. |
| * The intention here is to provide a valid default CBM with which a new |
| * resource group is initialized. The user can follow this with a |
| * modification to the CBM if the default does not satisfy the |
| * requirements. |
| */ |
| static u32 cbm_ensure_valid(u32 _val, struct rdt_resource *r) |
| { |
| unsigned int cbm_len = r->cache.cbm_len; |
| unsigned long first_bit, zero_bit; |
| unsigned long val = _val; |
| |
| if (!val) |
| return 0; |
| |
| first_bit = find_first_bit(&val, cbm_len); |
| zero_bit = find_next_zero_bit(&val, cbm_len, first_bit); |
| |
| /* Clear any remaining bits to ensure contiguous region */ |
| bitmap_clear(&val, zero_bit, cbm_len - zero_bit); |
| return (u32)val; |
| } |
| |
| /* |
| * Initialize cache resources per RDT domain |
| * |
| * Set the RDT domain up to start off with all usable allocations. That is, |
| * all shareable and unused bits. All-zero CBM is invalid. |
| */ |
| static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s, |
| u32 closid) |
| { |
| enum resctrl_conf_type peer_type = resctrl_peer_type(s->conf_type); |
| enum resctrl_conf_type t = s->conf_type; |
| struct resctrl_staged_config *cfg; |
| struct rdt_resource *r = s->res; |
| u32 used_b = 0, unused_b = 0; |
| unsigned long tmp_cbm; |
| enum rdtgrp_mode mode; |
| u32 peer_ctl, ctrl_val; |
| int i; |
| |
| cfg = &d->staged_config[t]; |
| cfg->have_new_ctrl = false; |
| cfg->new_ctrl = r->cache.shareable_bits; |
| used_b = r->cache.shareable_bits; |
| for (i = 0; i < closids_supported(); i++) { |
| if (closid_allocated(i) && i != closid) { |
| mode = rdtgroup_mode_by_closid(i); |
| if (mode == RDT_MODE_PSEUDO_LOCKSETUP) |
| /* |
| * ctrl values for locksetup aren't relevant |
| * until the schemata is written, and the mode |
| * becomes RDT_MODE_PSEUDO_LOCKED. |
| */ |
| continue; |
| /* |
| * If CDP is active include peer domain's |
| * usage to ensure there is no overlap |
| * with an exclusive group. |
| */ |
| if (resctrl_arch_get_cdp_enabled(r->rid)) |
| peer_ctl = resctrl_arch_get_config(r, d, i, |
| peer_type); |
| else |
| peer_ctl = 0; |
| ctrl_val = resctrl_arch_get_config(r, d, i, |
| s->conf_type); |
| used_b |= ctrl_val | peer_ctl; |
| if (mode == RDT_MODE_SHAREABLE) |
| cfg->new_ctrl |= ctrl_val | peer_ctl; |
| } |
| } |
| if (d->plr && d->plr->cbm > 0) |
| used_b |= d->plr->cbm; |
| unused_b = used_b ^ (BIT_MASK(r->cache.cbm_len) - 1); |
| unused_b &= BIT_MASK(r->cache.cbm_len) - 1; |
| cfg->new_ctrl |= unused_b; |
| /* |
| * Force the initial CBM to be valid, user can |
| * modify the CBM based on system availability. |
| */ |
| cfg->new_ctrl = cbm_ensure_valid(cfg->new_ctrl, r); |
| /* |
| * Assign the u32 CBM to an unsigned long to ensure that |
| * bitmap_weight() does not access out-of-bound memory. |
| */ |
| tmp_cbm = cfg->new_ctrl; |
| if (bitmap_weight(&tmp_cbm, r->cache.cbm_len) < r->cache.min_cbm_bits) { |
| rdt_last_cmd_printf("No space on %s:%d\n", s->name, d->id); |
| return -ENOSPC; |
| } |
| cfg->have_new_ctrl = true; |
| |
| return 0; |
| } |
| |
| /* |
| * Initialize cache resources with default values. |
| * |
| * A new RDT group is being created on an allocation capable (CAT) |
| * supporting system. Set this group up to start off with all usable |
| * allocations. |
| * |
| * If there are no more shareable bits available on any domain then |
| * the entire allocation will fail. |
| */ |
| static int rdtgroup_init_cat(struct resctrl_schema *s, u32 closid) |
| { |
| struct rdt_domain *d; |
| int ret; |
| |
| list_for_each_entry(d, &s->res->domains, list) { |
| ret = __init_one_rdt_domain(d, s, closid); |
| if (ret < 0) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /* Initialize MBA resource with default values. */ |
| static void rdtgroup_init_mba(struct rdt_resource *r, u32 closid) |
| { |
| struct resctrl_staged_config *cfg; |
| struct rdt_domain *d; |
| |
| list_for_each_entry(d, &r->domains, list) { |
| if (is_mba_sc(r)) { |
| d->mbps_val[closid] = MBA_MAX_MBPS; |
| continue; |
| } |
| |
| cfg = &d->staged_config[CDP_NONE]; |
| cfg->new_ctrl = r->default_ctrl; |
| cfg->have_new_ctrl = true; |
| } |
| } |
| |
| /* Initialize the RDT group's allocations. */ |
| static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp) |
| { |
| struct resctrl_schema *s; |
| struct rdt_resource *r; |
| int ret = 0; |
| |
| rdt_staged_configs_clear(); |
| |
| list_for_each_entry(s, &resctrl_schema_all, list) { |
| r = s->res; |
| if (r->rid == RDT_RESOURCE_MBA) { |
| rdtgroup_init_mba(r, rdtgrp->closid); |
| if (is_mba_sc(r)) |
| continue; |
| } else { |
| ret = rdtgroup_init_cat(s, rdtgrp->closid); |
| if (ret < 0) |
| goto out; |
| } |
| |
| ret = resctrl_arch_update_domains(r, rdtgrp->closid); |
| if (ret < 0) { |
| rdt_last_cmd_puts("Failed to initialize allocations\n"); |
| goto out; |
| } |
| |
| } |
| |
| rdtgrp->mode = RDT_MODE_SHAREABLE; |
| |
| out: |
| rdt_staged_configs_clear(); |
| return ret; |
| } |
| |
| static int mkdir_rdt_prepare(struct kernfs_node *parent_kn, |
| const char *name, umode_t mode, |
| enum rdt_group_type rtype, struct rdtgroup **r) |
| { |
| struct rdtgroup *prdtgrp, *rdtgrp; |
| struct kernfs_node *kn; |
| uint files = 0; |
| int ret; |
| |
| prdtgrp = rdtgroup_kn_lock_live(parent_kn); |
| if (!prdtgrp) { |
| ret = -ENODEV; |
| goto out_unlock; |
| } |
| |
| if (rtype == RDTMON_GROUP && |
| (prdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP || |
| prdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)) { |
| ret = -EINVAL; |
| rdt_last_cmd_puts("Pseudo-locking in progress\n"); |
| goto out_unlock; |
| } |
| |
| /* allocate the rdtgroup. */ |
| rdtgrp = kzalloc(sizeof(*rdtgrp), GFP_KERNEL); |
| if (!rdtgrp) { |
| ret = -ENOSPC; |
| rdt_last_cmd_puts("Kernel out of memory\n"); |
| goto out_unlock; |
| } |
| *r = rdtgrp; |
| rdtgrp->mon.parent = prdtgrp; |
| rdtgrp->type = rtype; |
| INIT_LIST_HEAD(&rdtgrp->mon.crdtgrp_list); |
| |
| /* kernfs creates the directory for rdtgrp */ |
| kn = kernfs_create_dir(parent_kn, name, mode, rdtgrp); |
| if (IS_ERR(kn)) { |
| ret = PTR_ERR(kn); |
| rdt_last_cmd_puts("kernfs create error\n"); |
| goto out_free_rgrp; |
| } |
| 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. Take one extra reference here, |
| * which will be dropped by kernfs_put() in rdtgroup_remove(). |
| */ |
| kernfs_get(kn); |
| |
| ret = rdtgroup_kn_set_ugid(kn); |
| if (ret) { |
| rdt_last_cmd_puts("kernfs perm error\n"); |
| goto out_destroy; |
| } |
| |
| files = RFTYPE_BASE | BIT(RF_CTRLSHIFT + rtype); |
| ret = rdtgroup_add_files(kn, files); |
| if (ret) { |
| rdt_last_cmd_puts("kernfs fill error\n"); |
| goto out_destroy; |
| } |
| |
| if (rdt_mon_capable) { |
| ret = alloc_rmid(); |
| if (ret < 0) { |
| rdt_last_cmd_puts("Out of RMIDs\n"); |
| goto out_destroy; |
| } |
| rdtgrp->mon.rmid = ret; |
| |
| ret = mkdir_mondata_all(kn, rdtgrp, &rdtgrp->mon.mon_data_kn); |
| if (ret) { |
| rdt_last_cmd_puts("kernfs subdir error\n"); |
| goto out_idfree; |
| } |
| } |
| kernfs_activate(kn); |
| |
| /* |
| * The caller unlocks the parent_kn upon success. |
| */ |
| return 0; |
| |
| out_idfree: |
| free_rmid(rdtgrp->mon.rmid); |
| out_destroy: |
| kernfs_put(rdtgrp->kn); |
| kernfs_remove(rdtgrp->kn); |
| out_free_rgrp: |
| kfree(rdtgrp); |
| out_unlock: |
| rdtgroup_kn_unlock(parent_kn); |
| return ret; |
| } |
| |
| static void mkdir_rdt_prepare_clean(struct rdtgroup *rgrp) |
| { |
| kernfs_remove(rgrp->kn); |
| free_rmid(rgrp->mon.rmid); |
| rdtgroup_remove(rgrp); |
| } |
| |
| /* |
| * Create a monitor group under "mon_groups" directory of a control |
| * and monitor group(ctrl_mon). This is a resource group |
| * to monitor a subset of tasks and cpus in its parent ctrl_mon group. |
| */ |
| static int rdtgroup_mkdir_mon(struct kernfs_node *parent_kn, |
| const char *name, umode_t mode) |
| { |
| struct rdtgroup *rdtgrp, *prgrp; |
| int ret; |
| |
| ret = mkdir_rdt_prepare(parent_kn, name, mode, RDTMON_GROUP, &rdtgrp); |
| if (ret) |
| return ret; |
| |
| prgrp = rdtgrp->mon.parent; |
| rdtgrp->closid = prgrp->closid; |
| |
| /* |
| * Add the rdtgrp to the list of rdtgrps the parent |
| * ctrl_mon group has to track. |
| */ |
| list_add_tail(&rdtgrp->mon.crdtgrp_list, &prgrp->mon.crdtgrp_list); |
| |
| rdtgroup_kn_unlock(parent_kn); |
| return ret; |
| } |
| |
| /* |
| * These are rdtgroups created under the root directory. Can be used |
| * to allocate and monitor resources. |
| */ |
| static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn, |
| const char *name, umode_t mode) |
| { |
| struct rdtgroup *rdtgrp; |
| struct kernfs_node *kn; |
| u32 closid; |
| int ret; |
| |
| ret = mkdir_rdt_prepare(parent_kn, name, mode, RDTCTRL_GROUP, &rdtgrp); |
| if (ret) |
| return ret; |
| |
| kn = rdtgrp->kn; |
| ret = closid_alloc(); |
| if (ret < 0) { |
| rdt_last_cmd_puts("Out of CLOSIDs\n"); |
| goto out_common_fail; |
| } |
| closid = ret; |
| ret = 0; |
| |
| rdtgrp->closid = closid; |
| ret = rdtgroup_init_alloc(rdtgrp); |
| if (ret < 0) |
| goto out_id_free; |
| |
| list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups); |
| |
| if (rdt_mon_capable) { |
| /* |
| * Create an empty mon_groups directory to hold the subset |
| * of tasks and cpus to monitor. |
| */ |
| ret = mongroup_create_dir(kn, rdtgrp, "mon_groups", NULL); |
| if (ret) { |
| rdt_last_cmd_puts("kernfs subdir error\n"); |
| goto out_del_list; |
| } |
| } |
| |
| goto out_unlock; |
| |
| out_del_list: |
| list_del(&rdtgrp->rdtgroup_list); |
| out_id_free: |
| closid_free(closid); |
| out_common_fail: |
| mkdir_rdt_prepare_clean(rdtgrp); |
| out_unlock: |
| rdtgroup_kn_unlock(parent_kn); |
| return ret; |
| } |
| |
| /* |
| * We allow creating mon groups only with in a directory called "mon_groups" |
| * which is present in every ctrl_mon group. Check if this is a valid |
| * "mon_groups" directory. |
| * |
| * 1. The directory should be named "mon_groups". |
| * 2. The mon group itself should "not" be named "mon_groups". |
| * This makes sure "mon_groups" directory always has a ctrl_mon group |
| * as parent. |
| */ |
| static bool is_mon_groups(struct kernfs_node *kn, const char *name) |
| { |
| return (!strcmp(kn->name, "mon_groups") && |
| strcmp(name, "mon_groups")); |
| } |
| |
| static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name, |
| umode_t mode) |
| { |
| /* Do not accept '\n' to avoid unparsable situation. */ |
| if (strchr(name, '\n')) |
| return -EINVAL; |
| |
| /* |
| * If the parent directory is the root directory and RDT |
| * allocation is supported, add a control and monitoring |
| * subdirectory |
| */ |
| if (rdt_alloc_capable && parent_kn == rdtgroup_default.kn) |
| return rdtgroup_mkdir_ctrl_mon(parent_kn, name, mode); |
| |
| /* |
| * If RDT monitoring is supported and the parent directory is a valid |
| * "mon_groups" directory, add a monitoring subdirectory. |
| */ |
| if (rdt_mon_capable && is_mon_groups(parent_kn, name)) |
| return rdtgroup_mkdir_mon(parent_kn, name, mode); |
| |
| return -EPERM; |
| } |
| |
| static int rdtgroup_rmdir_mon(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask) |
| { |
| struct rdtgroup *prdtgrp = rdtgrp->mon.parent; |
| int cpu; |
| |
| /* Give any tasks back to the parent group */ |
| rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask); |
| |
| /* Update per cpu rmid of the moved CPUs first */ |
| for_each_cpu(cpu, &rdtgrp->cpu_mask) |
| per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid; |
| /* |
| * Update the MSR on moved CPUs and CPUs which have moved |
| * task running on them. |
| */ |
| cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask); |
| update_closid_rmid(tmpmask, NULL); |
| |
| rdtgrp->flags = RDT_DELETED; |
| free_rmid(rdtgrp->mon.rmid); |
| |
| /* |
| * Remove the rdtgrp from the parent ctrl_mon group's list |
| */ |
| WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list)); |
| list_del(&rdtgrp->mon.crdtgrp_list); |
| |
| kernfs_remove(rdtgrp->kn); |
| |
| return 0; |
| } |
| |
| static int rdtgroup_ctrl_remove(struct rdtgroup *rdtgrp) |
| { |
| rdtgrp->flags = RDT_DELETED; |
| list_del(&rdtgrp->rdtgroup_list); |
| |
| kernfs_remove(rdtgrp->kn); |
| return 0; |
| } |
| |
| static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask) |
| { |
| int cpu; |
| |
| /* 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 and rmid of the moved CPUs first */ |
| for_each_cpu(cpu, &rdtgrp->cpu_mask) { |
| per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid; |
| per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid; |
| } |
| |
| /* |
| * Update the MSR on moved CPUs and CPUs which have moved |
| * task running on them. |
| */ |
| cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask); |
| update_closid_rmid(tmpmask, NULL); |
| |
| closid_free(rdtgrp->closid); |
| free_rmid(rdtgrp->mon.rmid); |
| |
| rdtgroup_ctrl_remove(rdtgrp); |
| |
| /* |
| * Free all the child monitor group rmids. |
| */ |
| free_all_child_rdtgrp(rdtgrp); |
| |
| return 0; |
| } |
| |
| static int rdtgroup_rmdir(struct kernfs_node *kn) |
| { |
| struct kernfs_node *parent_kn = kn->parent; |
| struct rdtgroup *rdtgrp; |
| cpumask_var_t tmpmask; |
| int ret = 0; |
| |
| if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) |
| return -ENOMEM; |
| |
| rdtgrp = rdtgroup_kn_lock_live(kn); |
| if (!rdtgrp) { |
| ret = -EPERM; |
| goto out; |
| } |
| |
| /* |
| * If the rdtgroup is a ctrl_mon group and parent directory |
| * is the root directory, remove the ctrl_mon group. |
| * |
| * If the rdtgroup is a mon group and parent directory |
| * is a valid "mon_groups" directory, remove the mon group. |
| */ |
| if (rdtgrp->type == RDTCTRL_GROUP && parent_kn == rdtgroup_default.kn && |
| rdtgrp != &rdtgroup_default) { |
| if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP || |
| rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) { |
| ret = rdtgroup_ctrl_remove(rdtgrp); |
| } else { |
| ret = rdtgroup_rmdir_ctrl(rdtgrp, tmpmask); |
| } |
| } else if (rdtgrp->type == RDTMON_GROUP && |
| is_mon_groups(parent_kn, kn->name)) { |
| ret = rdtgroup_rmdir_mon(rdtgrp, tmpmask); |
| } else { |
| ret = -EPERM; |
| } |
| |
| 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 (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3)) |
| seq_puts(seq, ",cdp"); |
| |
| if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2)) |
| seq_puts(seq, ",cdpl2"); |
| |
| if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl)) |
| seq_puts(seq, ",mba_MBps"); |
| |
| 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 | |
| KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK, |
| &rdtgroup_default); |
| if (IS_ERR(rdt_root)) |
| return PTR_ERR(rdt_root); |
| |
| mutex_lock(&rdtgroup_mutex); |
| |
| rdtgroup_default.closid = 0; |
| rdtgroup_default.mon.rmid = 0; |
| rdtgroup_default.type = RDTCTRL_GROUP; |
| INIT_LIST_HEAD(&rdtgroup_default.mon.crdtgrp_list); |
| |
| list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups); |
| |
| ret = rdtgroup_add_files(kernfs_root_to_node(rdt_root), RF_CTRL_BASE); |
| if (ret) { |
| kernfs_destroy_root(rdt_root); |
| goto out; |
| } |
| |
| rdtgroup_default.kn = kernfs_root_to_node(rdt_root); |
| kernfs_activate(rdtgroup_default.kn); |
| |
| out: |
| mutex_unlock(&rdtgroup_mutex); |
| |
| return ret; |
| } |
| |
| static void domain_destroy_mon_state(struct rdt_domain *d) |
| { |
| bitmap_free(d->rmid_busy_llc); |
| kfree(d->mbm_total); |
| kfree(d->mbm_local); |
| } |
| |
| void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d) |
| { |
| lockdep_assert_held(&rdtgroup_mutex); |
| |
| if (supports_mba_mbps() && r->rid == RDT_RESOURCE_MBA) |
| mba_sc_domain_destroy(r, d); |
| |
| if (!r->mon_capable) |
| return; |
| |
| /* |
| * If resctrl is mounted, remove all the |
| * per domain monitor data directories. |
| */ |
| if (static_branch_unlikely(&rdt_mon_enable_key)) |
| rmdir_mondata_subdir_allrdtgrp(r, d->id); |
| |
| if (is_mbm_enabled()) |
| cancel_delayed_work(&d->mbm_over); |
| if (is_llc_occupancy_enabled() && has_busy_rmid(r, d)) { |
| /* |
| * When a package is going down, forcefully |
| * decrement rmid->ebusy. There is no way to know |
| * that the L3 was flushed and hence may lead to |
| * incorrect counts in rare scenarios, but leaving |
| * the RMID as busy creates RMID leaks if the |
| * package never comes back. |
| */ |
| __check_limbo(d, true); |
| cancel_delayed_work(&d->cqm_limbo); |
| } |
| |
| domain_destroy_mon_state(d); |
| } |
| |
| static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d) |
| { |
| size_t tsize; |
| |
| if (is_llc_occupancy_enabled()) { |
| d->rmid_busy_llc = bitmap_zalloc(r->num_rmid, GFP_KERNEL); |
| if (!d->rmid_busy_llc) |
| return -ENOMEM; |
| } |
| if (is_mbm_total_enabled()) { |
| tsize = sizeof(*d->mbm_total); |
| d->mbm_total = kcalloc(r->num_rmid, tsize, GFP_KERNEL); |
| if (!d->mbm_total) { |
| bitmap_free(d->rmid_busy_llc); |
| return -ENOMEM; |
| } |
| } |
| if (is_mbm_local_enabled()) { |
| tsize = sizeof(*d->mbm_local); |
| d->mbm_local = kcalloc(r->num_rmid, tsize, GFP_KERNEL); |
| if (!d->mbm_local) { |
| bitmap_free(d->rmid_busy_llc); |
| kfree(d->mbm_total); |
| return -ENOMEM; |
| } |
| } |
| |
| return 0; |
| } |
| |
| int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d) |
| { |
| int err; |
| |
| lockdep_assert_held(&rdtgroup_mutex); |
| |
| if (supports_mba_mbps() && r->rid == RDT_RESOURCE_MBA) |
| /* RDT_RESOURCE_MBA is never mon_capable */ |
| return mba_sc_domain_allocate(r, d); |
| |
| if (!r->mon_capable) |
| return 0; |
| |
| err = domain_setup_mon_state(r, d); |
| if (err) |
| return err; |
| |
| if (is_mbm_enabled()) { |
| INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow); |
| mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL); |
| } |
| |
| if (is_llc_occupancy_enabled()) |
| INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo); |
| |
| /* If resctrl is mounted, add per domain monitor data directories. */ |
| if (static_branch_unlikely(&rdt_mon_enable_key)) |
| mkdir_mondata_subdir_allrdtgrp(r, d); |
| |
| 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; |
| |
| seq_buf_init(&last_cmd_status, last_cmd_status_buf, |
| sizeof(last_cmd_status_buf)); |
| |
| 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; |
| |
| /* |
| * Adding the resctrl debugfs directory here may not be ideal since |
| * it would let the resctrl debugfs directory appear on the debugfs |
| * filesystem before the resctrl filesystem is mounted. |
| * It may also be ok since that would enable debugging of RDT before |
| * resctrl is mounted. |
| * The reason why the debugfs directory is created here and not in |
| * rdt_get_tree() is because rdt_get_tree() takes rdtgroup_mutex and |
| * during the debugfs directory creation also &sb->s_type->i_mutex_key |
| * (the lockdep class of inode->i_rwsem). Other filesystem |
| * interactions (eg. SyS_getdents) have the lock ordering: |
| * &sb->s_type->i_mutex_key --> &mm->mmap_lock |
| * During mmap(), called with &mm->mmap_lock, the rdtgroup_mutex |
| * is taken, thus creating dependency: |
| * &mm->mmap_lock --> rdtgroup_mutex for the latter that can cause |
| * issues considering the other two lock dependencies. |
| * By creating the debugfs directory here we avoid a dependency |
| * that may cause deadlock (even though file operations cannot |
| * occur until the filesystem is mounted, but I do not know how to |
| * tell lockdep that). |
| */ |
| debugfs_resctrl = debugfs_create_dir("resctrl", NULL); |
| |
| return 0; |
| |
| cleanup_mountpoint: |
| sysfs_remove_mount_point(fs_kobj, "resctrl"); |
| cleanup_root: |
| kernfs_destroy_root(rdt_root); |
| |
| return ret; |
| } |
| |
| void __exit rdtgroup_exit(void) |
| { |
| debugfs_remove_recursive(debugfs_resctrl); |
| unregister_filesystem(&rdt_fs_type); |
| sysfs_remove_mount_point(fs_kobj, "resctrl"); |
| kernfs_destroy_root(rdt_root); |
| } |