diff options
Diffstat (limited to 'fs/resctrl/ctrlmondata.c')
-rw-r--r-- | fs/resctrl/ctrlmondata.c | 661 |
1 files changed, 661 insertions, 0 deletions
diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c new file mode 100644 index 000000000000..6ed2dfd4dbbd --- /dev/null +++ b/fs/resctrl/ctrlmondata.c @@ -0,0 +1,661 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Resource Director Technology(RDT) + * - Cache Allocation code. + * + * Copyright (C) 2016 Intel Corporation + * + * Authors: + * Fenghua Yu <fenghua.yu@intel.com> + * Tony Luck <tony.luck@intel.com> + * + * More information about RDT be found in the Intel (R) x86 Architecture + * Software Developer Manual June 2016, volume 3, section 17.17. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/cpu.h> +#include <linux/kernfs.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/tick.h> + +#include "internal.h" + +struct rdt_parse_data { + struct rdtgroup *rdtgrp; + char *buf; +}; + +typedef int (ctrlval_parser_t)(struct rdt_parse_data *data, + struct resctrl_schema *s, + struct rdt_ctrl_domain *d); + +/* + * Check whether MBA bandwidth percentage value is correct. The value is + * checked against the minimum and max bandwidth values specified by the + * hardware. The allocated bandwidth percentage is rounded to the next + * control step available on the hardware. + */ +static bool bw_validate(char *buf, u32 *data, struct rdt_resource *r) +{ + int ret; + u32 bw; + + /* + * Only linear delay values is supported for current Intel SKUs. + */ + if (!r->membw.delay_linear && r->membw.arch_needs_linear) { + rdt_last_cmd_puts("No support for non-linear MB domains\n"); + return false; + } + + ret = kstrtou32(buf, 10, &bw); + if (ret) { + rdt_last_cmd_printf("Invalid MB value %s\n", buf); + return false; + } + + /* Nothing else to do if software controller is enabled. */ + if (is_mba_sc(r)) { + *data = bw; + return true; + } + + if (bw < r->membw.min_bw || bw > r->membw.max_bw) { + rdt_last_cmd_printf("MB value %u out of range [%d,%d]\n", + bw, r->membw.min_bw, r->membw.max_bw); + return false; + } + + *data = roundup(bw, (unsigned long)r->membw.bw_gran); + return true; +} + +static int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s, + struct rdt_ctrl_domain *d) +{ + struct resctrl_staged_config *cfg; + u32 closid = data->rdtgrp->closid; + struct rdt_resource *r = s->res; + u32 bw_val; + + cfg = &d->staged_config[s->conf_type]; + if (cfg->have_new_ctrl) { + rdt_last_cmd_printf("Duplicate domain %d\n", d->hdr.id); + return -EINVAL; + } + + if (!bw_validate(data->buf, &bw_val, r)) + return -EINVAL; + + if (is_mba_sc(r)) { + d->mbps_val[closid] = bw_val; + return 0; + } + + cfg->new_ctrl = bw_val; + cfg->have_new_ctrl = true; + + return 0; +} + +/* + * Check whether a cache bit mask is valid. + * On Intel CPUs, non-contiguous 1s value support is indicated by CPUID: + * - CPUID.0x10.1:ECX[3]: L3 non-contiguous 1s value supported if 1 + * - CPUID.0x10.2:ECX[3]: L2 non-contiguous 1s value supported if 1 + * + * Haswell does not support a non-contiguous 1s value and additionally + * requires at least two bits set. + * AMD allows non-contiguous bitmasks. + */ +static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r) +{ + u32 supported_bits = BIT_MASK(r->cache.cbm_len) - 1; + unsigned int cbm_len = r->cache.cbm_len; + unsigned long first_bit, zero_bit, val; + int ret; + + ret = kstrtoul(buf, 16, &val); + if (ret) { + rdt_last_cmd_printf("Non-hex character in the mask %s\n", buf); + return false; + } + + if ((r->cache.min_cbm_bits > 0 && val == 0) || val > supported_bits) { + rdt_last_cmd_puts("Mask out of range\n"); + return false; + } + + first_bit = find_first_bit(&val, cbm_len); + zero_bit = find_next_zero_bit(&val, cbm_len, first_bit); + + /* Are non-contiguous bitmasks allowed? */ + if (!r->cache.arch_has_sparse_bitmasks && + (find_next_bit(&val, cbm_len, zero_bit) < cbm_len)) { + rdt_last_cmd_printf("The mask %lx has non-consecutive 1-bits\n", val); + return false; + } + + if ((zero_bit - first_bit) < r->cache.min_cbm_bits) { + rdt_last_cmd_printf("Need at least %d bits in the mask\n", + r->cache.min_cbm_bits); + return false; + } + + *data = val; + return true; +} + +/* + * Read one cache bit mask (hex). Check that it is valid for the current + * resource type. + */ +static int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s, + struct rdt_ctrl_domain *d) +{ + struct rdtgroup *rdtgrp = data->rdtgrp; + struct resctrl_staged_config *cfg; + struct rdt_resource *r = s->res; + u32 cbm_val; + + cfg = &d->staged_config[s->conf_type]; + if (cfg->have_new_ctrl) { + rdt_last_cmd_printf("Duplicate domain %d\n", d->hdr.id); + return -EINVAL; + } + + /* + * Cannot set up more than one pseudo-locked region in a cache + * hierarchy. + */ + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP && + rdtgroup_pseudo_locked_in_hierarchy(d)) { + rdt_last_cmd_puts("Pseudo-locked region in hierarchy\n"); + return -EINVAL; + } + + if (!cbm_validate(data->buf, &cbm_val, r)) + return -EINVAL; + + if ((rdtgrp->mode == RDT_MODE_EXCLUSIVE || + rdtgrp->mode == RDT_MODE_SHAREABLE) && + rdtgroup_cbm_overlaps_pseudo_locked(d, cbm_val)) { + rdt_last_cmd_puts("CBM overlaps with pseudo-locked region\n"); + return -EINVAL; + } + + /* + * The CBM may not overlap with the CBM of another closid if + * either is exclusive. + */ + if (rdtgroup_cbm_overlaps(s, d, cbm_val, rdtgrp->closid, true)) { + rdt_last_cmd_puts("Overlaps with exclusive group\n"); + return -EINVAL; + } + + if (rdtgroup_cbm_overlaps(s, d, cbm_val, rdtgrp->closid, false)) { + if (rdtgrp->mode == RDT_MODE_EXCLUSIVE || + rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + rdt_last_cmd_puts("Overlaps with other group\n"); + return -EINVAL; + } + } + + cfg->new_ctrl = cbm_val; + cfg->have_new_ctrl = true; + + return 0; +} + +/* + * For each domain in this resource we expect to find a series of: + * id=mask + * separated by ";". The "id" is in decimal, and must match one of + * the "id"s for this resource. + */ +static int parse_line(char *line, struct resctrl_schema *s, + struct rdtgroup *rdtgrp) +{ + enum resctrl_conf_type t = s->conf_type; + ctrlval_parser_t *parse_ctrlval = NULL; + struct resctrl_staged_config *cfg; + struct rdt_resource *r = s->res; + struct rdt_parse_data data; + struct rdt_ctrl_domain *d; + char *dom = NULL, *id; + unsigned long dom_id; + + /* Walking r->domains, ensure it can't race with cpuhp */ + lockdep_assert_cpus_held(); + + switch (r->schema_fmt) { + case RESCTRL_SCHEMA_BITMAP: + parse_ctrlval = &parse_cbm; + break; + case RESCTRL_SCHEMA_RANGE: + parse_ctrlval = &parse_bw; + break; + } + + if (WARN_ON_ONCE(!parse_ctrlval)) + return -EINVAL; + + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP && + (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) { + rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n"); + return -EINVAL; + } + +next: + if (!line || line[0] == '\0') + return 0; + dom = strsep(&line, ";"); + id = strsep(&dom, "="); + if (!dom || kstrtoul(id, 10, &dom_id)) { + rdt_last_cmd_puts("Missing '=' or non-numeric domain\n"); + return -EINVAL; + } + dom = strim(dom); + list_for_each_entry(d, &r->ctrl_domains, hdr.list) { + if (d->hdr.id == dom_id) { + data.buf = dom; + data.rdtgrp = rdtgrp; + if (parse_ctrlval(&data, s, d)) + return -EINVAL; + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + cfg = &d->staged_config[t]; + /* + * In pseudo-locking setup mode and just + * parsed a valid CBM that should be + * pseudo-locked. Only one locked region per + * resource group and domain so just do + * the required initialization for single + * region and return. + */ + rdtgrp->plr->s = s; + rdtgrp->plr->d = d; + rdtgrp->plr->cbm = cfg->new_ctrl; + d->plr = rdtgrp->plr; + return 0; + } + goto next; + } + } + return -EINVAL; +} + +static int rdtgroup_parse_resource(char *resname, char *tok, + struct rdtgroup *rdtgrp) +{ + struct resctrl_schema *s; + + list_for_each_entry(s, &resctrl_schema_all, list) { + if (!strcmp(resname, s->name) && rdtgrp->closid < s->num_closid) + return parse_line(tok, s, rdtgrp); + } + rdt_last_cmd_printf("Unknown or unsupported resource name '%s'\n", resname); + return -EINVAL; +} + +ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct resctrl_schema *s; + struct rdtgroup *rdtgrp; + struct rdt_resource *r; + char *tok, *resname; + 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(); + + /* + * No changes to pseudo-locked region allowed. It has to be removed + * and re-created instead. + */ + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) { + ret = -EINVAL; + rdt_last_cmd_puts("Resource group is pseudo-locked\n"); + goto out; + } + + rdt_staged_configs_clear(); + + while ((tok = strsep(&buf, "\n")) != NULL) { + resname = strim(strsep(&tok, ":")); + if (!tok) { + rdt_last_cmd_puts("Missing ':'\n"); + ret = -EINVAL; + goto out; + } + if (tok[0] == '\0') { + rdt_last_cmd_printf("Missing '%s' value\n", resname); + ret = -EINVAL; + goto out; + } + ret = rdtgroup_parse_resource(resname, tok, rdtgrp); + if (ret) + goto out; + } + + list_for_each_entry(s, &resctrl_schema_all, list) { + r = s->res; + + /* + * Writes to mba_sc resources update the software controller, + * not the control MSR. + */ + if (is_mba_sc(r)) + continue; + + ret = resctrl_arch_update_domains(r, rdtgrp->closid); + if (ret) + goto out; + } + + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + /* + * If pseudo-locking fails we keep the resource group in + * mode RDT_MODE_PSEUDO_LOCKSETUP with its class of service + * active and updated for just the domain the pseudo-locked + * region was requested for. + */ + ret = rdtgroup_pseudo_lock_create(rdtgrp); + } + +out: + rdt_staged_configs_clear(); + rdtgroup_kn_unlock(of->kn); + return ret ?: nbytes; +} + +static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int closid) +{ + struct rdt_resource *r = schema->res; + struct rdt_ctrl_domain *dom; + bool sep = false; + u32 ctrl_val; + + /* Walking r->domains, ensure it can't race with cpuhp */ + lockdep_assert_cpus_held(); + + seq_printf(s, "%*s:", max_name_width, schema->name); + list_for_each_entry(dom, &r->ctrl_domains, hdr.list) { + if (sep) + seq_puts(s, ";"); + + if (is_mba_sc(r)) + ctrl_val = dom->mbps_val[closid]; + else + ctrl_val = resctrl_arch_get_config(r, dom, closid, + schema->conf_type); + + seq_printf(s, schema->fmt_str, dom->hdr.id, ctrl_val); + sep = true; + } + seq_puts(s, "\n"); +} + +int rdtgroup_schemata_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct resctrl_schema *schema; + struct rdtgroup *rdtgrp; + int ret = 0; + u32 closid; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (rdtgrp) { + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + list_for_each_entry(schema, &resctrl_schema_all, list) { + seq_printf(s, "%s:uninitialized\n", schema->name); + } + } else 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:%d=%x\n", + rdtgrp->plr->s->res->name, + rdtgrp->plr->d->hdr.id, + rdtgrp->plr->cbm); + } + } else { + closid = rdtgrp->closid; + list_for_each_entry(schema, &resctrl_schema_all, list) { + if (closid < schema->num_closid) + show_doms(s, schema, closid); + } + } + } else { + ret = -ENOENT; + } + rdtgroup_kn_unlock(of->kn); + return ret; +} + +static int smp_mon_event_count(void *arg) +{ + mon_event_count(arg); + + return 0; +} + +ssize_t rdtgroup_mba_mbps_event_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct rdtgroup *rdtgrp; + 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(); + + if (!strcmp(buf, "mbm_local_bytes")) { + if (resctrl_arch_is_mbm_local_enabled()) + rdtgrp->mba_mbps_event = QOS_L3_MBM_LOCAL_EVENT_ID; + else + ret = -EINVAL; + } else if (!strcmp(buf, "mbm_total_bytes")) { + if (resctrl_arch_is_mbm_total_enabled()) + rdtgrp->mba_mbps_event = QOS_L3_MBM_TOTAL_EVENT_ID; + else + ret = -EINVAL; + } else { + ret = -EINVAL; + } + + if (ret) + rdt_last_cmd_printf("Unsupported event id '%s'\n", buf); + + rdtgroup_kn_unlock(of->kn); + + return ret ?: nbytes; +} + +int rdtgroup_mba_mbps_event_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) { + switch (rdtgrp->mba_mbps_event) { + case QOS_L3_MBM_LOCAL_EVENT_ID: + seq_puts(s, "mbm_local_bytes\n"); + break; + case QOS_L3_MBM_TOTAL_EVENT_ID: + seq_puts(s, "mbm_total_bytes\n"); + break; + default: + pr_warn_once("Bad event %d\n", rdtgrp->mba_mbps_event); + ret = -EINVAL; + break; + } + } else { + ret = -ENOENT; + } + + rdtgroup_kn_unlock(of->kn); + + return ret; +} + +struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id, + struct list_head **pos) +{ + struct rdt_domain_hdr *d; + struct list_head *l; + + list_for_each(l, h) { + d = list_entry(l, struct rdt_domain_hdr, list); + /* When id is found, return its domain. */ + if (id == d->id) + return d; + /* Stop searching when finding id's position in sorted list. */ + if (id < d->id) + break; + } + + if (pos) + *pos = l; + + return NULL; +} + +void mon_event_read(struct rmid_read *rr, struct rdt_resource *r, + struct rdt_mon_domain *d, struct rdtgroup *rdtgrp, + cpumask_t *cpumask, int evtid, int first) +{ + int cpu; + + /* When picking a CPU from cpu_mask, ensure it can't race with cpuhp */ + lockdep_assert_cpus_held(); + + /* + * Setup the parameters to pass to mon_event_count() to read the data. + */ + rr->rgrp = rdtgrp; + rr->evtid = evtid; + rr->r = r; + rr->d = d; + rr->first = first; + rr->arch_mon_ctx = resctrl_arch_mon_ctx_alloc(r, evtid); + if (IS_ERR(rr->arch_mon_ctx)) { + rr->err = -EINVAL; + return; + } + + cpu = cpumask_any_housekeeping(cpumask, RESCTRL_PICK_ANY_CPU); + + /* + * cpumask_any_housekeeping() prefers housekeeping CPUs, but + * are all the CPUs nohz_full? If yes, pick a CPU to IPI. + * MPAM's resctrl_arch_rmid_read() is unable to read the + * counters on some platforms if its called in IRQ context. + */ + if (tick_nohz_full_cpu(cpu)) + smp_call_function_any(cpumask, mon_event_count, rr, 1); + else + smp_call_on_cpu(cpu, smp_mon_event_count, rr, false); + + resctrl_arch_mon_ctx_free(r, evtid, rr->arch_mon_ctx); +} + +int rdtgroup_mondata_show(struct seq_file *m, void *arg) +{ + struct kernfs_open_file *of = m->private; + enum resctrl_res_level resid; + enum resctrl_event_id evtid; + struct rdt_domain_hdr *hdr; + struct rmid_read rr = {0}; + struct rdt_mon_domain *d; + struct rdtgroup *rdtgrp; + struct rdt_resource *r; + struct mon_data *md; + int domid, ret = 0; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (!rdtgrp) { + ret = -ENOENT; + goto out; + } + + md = of->kn->priv; + if (WARN_ON_ONCE(!md)) { + ret = -EIO; + goto out; + } + + resid = md->rid; + domid = md->domid; + evtid = md->evtid; + r = resctrl_arch_get_resource(resid); + + if (md->sum) { + /* + * This file requires summing across all domains that share + * the L3 cache id that was provided in the "domid" field of the + * struct mon_data. Search all domains in the resource for + * one that matches this cache id. + */ + list_for_each_entry(d, &r->mon_domains, hdr.list) { + if (d->ci->id == domid) { + rr.ci = d->ci; + mon_event_read(&rr, r, NULL, rdtgrp, + &d->ci->shared_cpu_map, evtid, false); + goto checkresult; + } + } + ret = -ENOENT; + goto out; + } else { + /* + * This file provides data from a single domain. Search + * the resource to find the domain with "domid". + */ + hdr = resctrl_find_domain(&r->mon_domains, domid, NULL); + if (!hdr || WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN)) { + ret = -ENOENT; + goto out; + } + d = container_of(hdr, struct rdt_mon_domain, hdr); + mon_event_read(&rr, r, d, rdtgrp, &d->hdr.cpu_mask, evtid, false); + } + +checkresult: + + if (rr.err == -EIO) + seq_puts(m, "Error\n"); + else if (rr.err == -EINVAL) + seq_puts(m, "Unavailable\n"); + else + seq_printf(m, "%llu\n", rr.val); + +out: + rdtgroup_kn_unlock(of->kn); + return ret; +} |