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-rw-r--r--fs/resctrl/ctrlmondata.c661
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;
+}
generated by cgit (git 2.34.1) at 2025-05-29 18:25:33 +0000