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Diffstat (limited to 'arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c')
-rw-r--r--arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
new file mode 100644
index 000000000000..f6ea94f8954a
--- /dev/null
+++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
@@ -0,0 +1,341 @@
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * More information about RDT be found in the Intel (R) x86 Architecture
+ * Software Developer Manual June 2016, volume 3, section 17.17.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernfs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include "intel_rdt.h"
+
+/*
+ * 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, unsigned long *data, struct rdt_resource *r)
+{
+ unsigned long bw;
+ int ret;
+
+ /*
+ * Only linear delay values is supported for current Intel SKUs.
+ */
+ if (!r->membw.delay_linear)
+ return false;
+
+ ret = kstrtoul(buf, 10, &bw);
+ if (ret)
+ return false;
+
+ if (bw < r->membw.min_bw || bw > r->default_ctrl)
+ return false;
+
+ *data = roundup(bw, (unsigned long)r->membw.bw_gran);
+ return true;
+}
+
+int parse_bw(char *buf, struct rdt_resource *r, struct rdt_domain *d)
+{
+ unsigned long data;
+
+ if (d->have_new_ctrl)
+ return -EINVAL;
+
+ if (!bw_validate(buf, &data, r))
+ return -EINVAL;
+ d->new_ctrl = data;
+ d->have_new_ctrl = true;
+
+ return 0;
+}
+
+/*
+ * Check whether a cache bit mask is valid. The SDM says:
+ * Please note that all (and only) contiguous '1' combinations
+ * are allowed (e.g. FFFFH, 0FF0H, 003CH, etc.).
+ * Additionally Haswell requires at least two bits set.
+ */
+static bool cbm_validate(char *buf, unsigned long *data, struct rdt_resource *r)
+{
+ unsigned long first_bit, zero_bit, val;
+ unsigned int cbm_len = r->cache.cbm_len;
+ int ret;
+
+ ret = kstrtoul(buf, 16, &val);
+ if (ret)
+ return false;
+
+ if (val == 0 || val > r->default_ctrl)
+ return false;
+
+ first_bit = find_first_bit(&val, cbm_len);
+ zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);
+
+ if (find_next_bit(&val, cbm_len, zero_bit) < cbm_len)
+ return false;
+
+ if ((zero_bit - first_bit) < 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.
+ */
+int parse_cbm(char *buf, struct rdt_resource *r, struct rdt_domain *d)
+{
+ unsigned long data;
+
+ if (d->have_new_ctrl)
+ return -EINVAL;
+
+ if(!cbm_validate(buf, &data, r))
+ return -EINVAL;
+ d->new_ctrl = data;
+ d->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 rdt_resource *r)
+{
+ char *dom = NULL, *id;
+ struct rdt_domain *d;
+ unsigned long dom_id;
+
+next:
+ if (!line || line[0] == '\0')
+ return 0;
+ dom = strsep(&line, ";");
+ id = strsep(&dom, "=");
+ if (!dom || kstrtoul(id, 10, &dom_id))
+ return -EINVAL;
+ dom = strim(dom);
+ list_for_each_entry(d, &r->domains, list) {
+ if (d->id == dom_id) {
+ if (r->parse_ctrlval(dom, r, d))
+ return -EINVAL;
+ goto next;
+ }
+ }
+ return -EINVAL;
+}
+
+static int update_domains(struct rdt_resource *r, int closid)
+{
+ struct msr_param msr_param;
+ cpumask_var_t cpu_mask;
+ struct rdt_domain *d;
+ int cpu;
+
+ if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
+ return -ENOMEM;
+
+ msr_param.low = closid;
+ msr_param.high = msr_param.low + 1;
+ msr_param.res = r;
+
+ list_for_each_entry(d, &r->domains, list) {
+ if (d->have_new_ctrl && d->new_ctrl != d->ctrl_val[closid]) {
+ cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
+ d->ctrl_val[closid] = d->new_ctrl;
+ }
+ }
+ if (cpumask_empty(cpu_mask))
+ goto done;
+ 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 other cpus. */
+ smp_call_function_many(cpu_mask, rdt_ctrl_update, &msr_param, 1);
+ put_cpu();
+
+done:
+ free_cpumask_var(cpu_mask);
+
+ return 0;
+}
+
+static int rdtgroup_parse_resource(char *resname, char *tok, int closid)
+{
+ struct rdt_resource *r;
+
+ for_each_alloc_enabled_rdt_resource(r) {
+ if (!strcmp(resname, r->name) && closid < r->num_closid)
+ return parse_line(tok, r);
+ }
+ return -EINVAL;
+}
+
+ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
+ char *buf, size_t nbytes, loff_t off)
+{
+ struct rdtgroup *rdtgrp;
+ struct rdt_domain *dom;
+ struct rdt_resource *r;
+ char *tok, *resname;
+ int closid, 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;
+ }
+
+ closid = rdtgrp->closid;
+
+ for_each_alloc_enabled_rdt_resource(r) {
+ list_for_each_entry(dom, &r->domains, list)
+ dom->have_new_ctrl = false;
+ }
+
+ while ((tok = strsep(&buf, "\n")) != NULL) {
+ resname = strim(strsep(&tok, ":"));
+ if (!tok) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = rdtgroup_parse_resource(resname, tok, closid);
+ if (ret)
+ goto out;
+ }
+
+ for_each_alloc_enabled_rdt_resource(r) {
+ ret = update_domains(r, closid);
+ if (ret)
+ goto out;
+ }
+
+out:
+ rdtgroup_kn_unlock(of->kn);
+ return ret ?: nbytes;
+}
+
+static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid)
+{
+ struct rdt_domain *dom;
+ bool sep = false;
+
+ seq_printf(s, "%*s:", max_name_width, r->name);
+ list_for_each_entry(dom, &r->domains, list) {
+ if (sep)
+ seq_puts(s, ";");
+ seq_printf(s, r->format_str, dom->id, max_data_width,
+ dom->ctrl_val[closid]);
+ sep = true;
+ }
+ seq_puts(s, "\n");
+}
+
+int rdtgroup_schemata_show(struct kernfs_open_file *of,
+ struct seq_file *s, void *v)
+{
+ struct rdtgroup *rdtgrp;
+ struct rdt_resource *r;
+ int ret = 0;
+ u32 closid;
+
+ rdtgrp = rdtgroup_kn_lock_live(of->kn);
+ if (rdtgrp) {
+ closid = rdtgrp->closid;
+ for_each_alloc_enabled_rdt_resource(r) {
+ if (closid < r->num_closid)
+ show_doms(s, r, closid);
+ }
+ } else {
+ ret = -ENOENT;
+ }
+ rdtgroup_kn_unlock(of->kn);
+ return ret;
+}
+
+void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
+ struct rdtgroup *rdtgrp, int evtid, int first)
+{
+ /*
+ * setup the parameters to send to the IPI to read the data.
+ */
+ rr->rgrp = rdtgrp;
+ rr->evtid = evtid;
+ rr->d = d;
+ rr->val = 0;
+ rr->first = first;
+
+ smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);
+}
+
+int rdtgroup_mondata_show(struct seq_file *m, void *arg)
+{
+ struct kernfs_open_file *of = m->private;
+ u32 resid, evtid, domid;
+ struct rdtgroup *rdtgrp;
+ struct rdt_resource *r;
+ union mon_data_bits md;
+ struct rdt_domain *d;
+ struct rmid_read rr;
+ int ret = 0;
+
+ rdtgrp = rdtgroup_kn_lock_live(of->kn);
+
+ md.priv = of->kn->priv;
+ resid = md.u.rid;
+ domid = md.u.domid;
+ evtid = md.u.evtid;
+
+ r = &rdt_resources_all[resid];
+ d = rdt_find_domain(r, domid, NULL);
+ if (!d) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ mon_event_read(&rr, d, rdtgrp, evtid, false);
+
+ if (rr.val & RMID_VAL_ERROR)
+ seq_puts(m, "Error\n");
+ else if (rr.val & RMID_VAL_UNAVAIL)
+ seq_puts(m, "Unavailable\n");
+ else
+ seq_printf(m, "%llu\n", rr.val * r->mon_scale);
+
+out:
+ rdtgroup_kn_unlock(of->kn);
+ return ret;
+}