1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Resource Director Technology(RDT)
4 * - Cache Allocation code.
5 *
6 * Copyright (C) 2016 Intel Corporation
7 *
8 * Authors:
9 * Fenghua Yu <fenghua.yu@intel.com>
10 * Tony Luck <tony.luck@intel.com>
11 *
12 * More information about RDT be found in the Intel (R) x86 Architecture
13 * Software Developer Manual June 2016, volume 3, section 17.17.
14 */
15
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18 #include <linux/cpu.h>
19 #include <linux/kernfs.h>
20 #include <linux/seq_file.h>
21 #include <linux/slab.h>
22 #include "internal.h"
23
24 /*
25 * Check whether MBA bandwidth percentage value is correct. The value is
26 * checked against the minimum and max bandwidth values specified by the
27 * hardware. The allocated bandwidth percentage is rounded to the next
28 * control step available on the hardware.
29 */
bw_validate(char * buf,u32 * data,struct rdt_resource * r)30 static bool bw_validate(char *buf, u32 *data, struct rdt_resource *r)
31 {
32 int ret;
33 u32 bw;
34
35 /*
36 * Only linear delay values is supported for current Intel SKUs.
37 */
38 if (!r->membw.delay_linear && r->membw.arch_needs_linear) {
39 rdt_last_cmd_puts("No support for non-linear MB domains\n");
40 return false;
41 }
42
43 ret = kstrtou32(buf, 10, &bw);
44 if (ret) {
45 rdt_last_cmd_printf("Invalid MB value %s\n", buf);
46 return false;
47 }
48
49 /* Nothing else to do if software controller is enabled. */
50 if (is_mba_sc(r)) {
51 *data = bw;
52 return true;
53 }
54
55 if (bw < r->membw.min_bw || bw > r->default_ctrl) {
56 rdt_last_cmd_printf("MB value %u out of range [%d,%d]\n",
57 bw, r->membw.min_bw, r->default_ctrl);
58 return false;
59 }
60
61 *data = roundup(bw, (unsigned long)r->membw.bw_gran);
62 return true;
63 }
64
parse_bw(struct rdt_parse_data * data,struct resctrl_schema * s,struct rdt_domain * d)65 int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
66 struct rdt_domain *d)
67 {
68 struct resctrl_staged_config *cfg;
69 u32 closid = data->rdtgrp->closid;
70 struct rdt_resource *r = s->res;
71 u32 bw_val;
72
73 cfg = &d->staged_config[s->conf_type];
74 if (cfg->have_new_ctrl) {
75 rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
76 return -EINVAL;
77 }
78
79 if (!bw_validate(data->buf, &bw_val, r))
80 return -EINVAL;
81
82 if (is_mba_sc(r)) {
83 d->mbps_val[closid] = bw_val;
84 return 0;
85 }
86
87 cfg->new_ctrl = bw_val;
88 cfg->have_new_ctrl = true;
89
90 return 0;
91 }
92
93 /*
94 * Check whether a cache bit mask is valid.
95 * For Intel the SDM says:
96 * Please note that all (and only) contiguous '1' combinations
97 * are allowed (e.g. FFFFH, 0FF0H, 003CH, etc.).
98 * Additionally Haswell requires at least two bits set.
99 * AMD allows non-contiguous bitmasks.
100 */
cbm_validate(char * buf,u32 * data,struct rdt_resource * r)101 static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
102 {
103 unsigned long first_bit, zero_bit, val;
104 unsigned int cbm_len = r->cache.cbm_len;
105 int ret;
106
107 ret = kstrtoul(buf, 16, &val);
108 if (ret) {
109 rdt_last_cmd_printf("Non-hex character in the mask %s\n", buf);
110 return false;
111 }
112
113 if ((r->cache.min_cbm_bits > 0 && val == 0) || val > r->default_ctrl) {
114 rdt_last_cmd_puts("Mask out of range\n");
115 return false;
116 }
117
118 first_bit = find_first_bit(&val, cbm_len);
119 zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);
120
121 /* Are non-contiguous bitmaps allowed? */
122 if (!r->cache.arch_has_sparse_bitmaps &&
123 (find_next_bit(&val, cbm_len, zero_bit) < cbm_len)) {
124 rdt_last_cmd_printf("The mask %lx has non-consecutive 1-bits\n", val);
125 return false;
126 }
127
128 if ((zero_bit - first_bit) < r->cache.min_cbm_bits) {
129 rdt_last_cmd_printf("Need at least %d bits in the mask\n",
130 r->cache.min_cbm_bits);
131 return false;
132 }
133
134 *data = val;
135 return true;
136 }
137
138 /*
139 * Read one cache bit mask (hex). Check that it is valid for the current
140 * resource type.
141 */
parse_cbm(struct rdt_parse_data * data,struct resctrl_schema * s,struct rdt_domain * d)142 int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
143 struct rdt_domain *d)
144 {
145 struct rdtgroup *rdtgrp = data->rdtgrp;
146 struct resctrl_staged_config *cfg;
147 struct rdt_resource *r = s->res;
148 u32 cbm_val;
149
150 cfg = &d->staged_config[s->conf_type];
151 if (cfg->have_new_ctrl) {
152 rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
153 return -EINVAL;
154 }
155
156 /*
157 * Cannot set up more than one pseudo-locked region in a cache
158 * hierarchy.
159 */
160 if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
161 rdtgroup_pseudo_locked_in_hierarchy(d)) {
162 rdt_last_cmd_puts("Pseudo-locked region in hierarchy\n");
163 return -EINVAL;
164 }
165
166 if (!cbm_validate(data->buf, &cbm_val, r))
167 return -EINVAL;
168
169 if ((rdtgrp->mode == RDT_MODE_EXCLUSIVE ||
170 rdtgrp->mode == RDT_MODE_SHAREABLE) &&
171 rdtgroup_cbm_overlaps_pseudo_locked(d, cbm_val)) {
172 rdt_last_cmd_puts("CBM overlaps with pseudo-locked region\n");
173 return -EINVAL;
174 }
175
176 /*
177 * The CBM may not overlap with the CBM of another closid if
178 * either is exclusive.
179 */
180 if (rdtgroup_cbm_overlaps(s, d, cbm_val, rdtgrp->closid, true)) {
181 rdt_last_cmd_puts("Overlaps with exclusive group\n");
182 return -EINVAL;
183 }
184
185 if (rdtgroup_cbm_overlaps(s, d, cbm_val, rdtgrp->closid, false)) {
186 if (rdtgrp->mode == RDT_MODE_EXCLUSIVE ||
187 rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
188 rdt_last_cmd_puts("Overlaps with other group\n");
189 return -EINVAL;
190 }
191 }
192
193 cfg->new_ctrl = cbm_val;
194 cfg->have_new_ctrl = true;
195
196 return 0;
197 }
198
199 /*
200 * For each domain in this resource we expect to find a series of:
201 * id=mask
202 * separated by ";". The "id" is in decimal, and must match one of
203 * the "id"s for this resource.
204 */
parse_line(char * line,struct resctrl_schema * s,struct rdtgroup * rdtgrp)205 static int parse_line(char *line, struct resctrl_schema *s,
206 struct rdtgroup *rdtgrp)
207 {
208 enum resctrl_conf_type t = s->conf_type;
209 struct resctrl_staged_config *cfg;
210 struct rdt_resource *r = s->res;
211 struct rdt_parse_data data;
212 char *dom = NULL, *id;
213 struct rdt_domain *d;
214 unsigned long dom_id;
215
216 if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
217 (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) {
218 rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
219 return -EINVAL;
220 }
221
222 next:
223 if (!line || line[0] == '\0')
224 return 0;
225 dom = strsep(&line, ";");
226 id = strsep(&dom, "=");
227 if (!dom || kstrtoul(id, 10, &dom_id)) {
228 rdt_last_cmd_puts("Missing '=' or non-numeric domain\n");
229 return -EINVAL;
230 }
231 dom = strim(dom);
232 list_for_each_entry(d, &r->domains, list) {
233 if (d->id == dom_id) {
234 data.buf = dom;
235 data.rdtgrp = rdtgrp;
236 if (r->parse_ctrlval(&data, s, d))
237 return -EINVAL;
238 if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
239 cfg = &d->staged_config[t];
240 /*
241 * In pseudo-locking setup mode and just
242 * parsed a valid CBM that should be
243 * pseudo-locked. Only one locked region per
244 * resource group and domain so just do
245 * the required initialization for single
246 * region and return.
247 */
248 rdtgrp->plr->s = s;
249 rdtgrp->plr->d = d;
250 rdtgrp->plr->cbm = cfg->new_ctrl;
251 d->plr = rdtgrp->plr;
252 return 0;
253 }
254 goto next;
255 }
256 }
257 return -EINVAL;
258 }
259
get_config_index(u32 closid,enum resctrl_conf_type type)260 static u32 get_config_index(u32 closid, enum resctrl_conf_type type)
261 {
262 switch (type) {
263 default:
264 case CDP_NONE:
265 return closid;
266 case CDP_CODE:
267 return closid * 2 + 1;
268 case CDP_DATA:
269 return closid * 2;
270 }
271 }
272
apply_config(struct rdt_hw_domain * hw_dom,struct resctrl_staged_config * cfg,u32 idx,cpumask_var_t cpu_mask)273 static bool apply_config(struct rdt_hw_domain *hw_dom,
274 struct resctrl_staged_config *cfg, u32 idx,
275 cpumask_var_t cpu_mask)
276 {
277 struct rdt_domain *dom = &hw_dom->d_resctrl;
278
279 if (cfg->new_ctrl != hw_dom->ctrl_val[idx]) {
280 cpumask_set_cpu(cpumask_any(&dom->cpu_mask), cpu_mask);
281 hw_dom->ctrl_val[idx] = cfg->new_ctrl;
282
283 return true;
284 }
285
286 return false;
287 }
288
resctrl_arch_update_one(struct rdt_resource * r,struct rdt_domain * d,u32 closid,enum resctrl_conf_type t,u32 cfg_val)289 int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_domain *d,
290 u32 closid, enum resctrl_conf_type t, u32 cfg_val)
291 {
292 struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
293 struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
294 u32 idx = get_config_index(closid, t);
295 struct msr_param msr_param;
296
297 if (!cpumask_test_cpu(smp_processor_id(), &d->cpu_mask))
298 return -EINVAL;
299
300 hw_dom->ctrl_val[idx] = cfg_val;
301
302 msr_param.res = r;
303 msr_param.low = idx;
304 msr_param.high = idx + 1;
305 hw_res->msr_update(d, &msr_param, r);
306
307 return 0;
308 }
309
resctrl_arch_update_domains(struct rdt_resource * r,u32 closid)310 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid)
311 {
312 struct resctrl_staged_config *cfg;
313 struct rdt_hw_domain *hw_dom;
314 struct msr_param msr_param;
315 enum resctrl_conf_type t;
316 cpumask_var_t cpu_mask;
317 struct rdt_domain *d;
318 u32 idx;
319
320 if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
321 return -ENOMEM;
322
323 msr_param.res = NULL;
324 list_for_each_entry(d, &r->domains, list) {
325 hw_dom = resctrl_to_arch_dom(d);
326 for (t = 0; t < CDP_NUM_TYPES; t++) {
327 cfg = &hw_dom->d_resctrl.staged_config[t];
328 if (!cfg->have_new_ctrl)
329 continue;
330
331 idx = get_config_index(closid, t);
332 if (!apply_config(hw_dom, cfg, idx, cpu_mask))
333 continue;
334
335 if (!msr_param.res) {
336 msr_param.low = idx;
337 msr_param.high = msr_param.low + 1;
338 msr_param.res = r;
339 } else {
340 msr_param.low = min(msr_param.low, idx);
341 msr_param.high = max(msr_param.high, idx + 1);
342 }
343 }
344 }
345
346 if (cpumask_empty(cpu_mask))
347 goto done;
348
349 /* Update resource control msr on all the CPUs. */
350 on_each_cpu_mask(cpu_mask, rdt_ctrl_update, &msr_param, 1);
351
352 done:
353 free_cpumask_var(cpu_mask);
354
355 return 0;
356 }
357
rdtgroup_parse_resource(char * resname,char * tok,struct rdtgroup * rdtgrp)358 static int rdtgroup_parse_resource(char *resname, char *tok,
359 struct rdtgroup *rdtgrp)
360 {
361 struct resctrl_schema *s;
362
363 list_for_each_entry(s, &resctrl_schema_all, list) {
364 if (!strcmp(resname, s->name) && rdtgrp->closid < s->num_closid)
365 return parse_line(tok, s, rdtgrp);
366 }
367 rdt_last_cmd_printf("Unknown or unsupported resource name '%s'\n", resname);
368 return -EINVAL;
369 }
370
rdtgroup_schemata_write(struct kernfs_open_file * of,char * buf,size_t nbytes,loff_t off)371 ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
372 char *buf, size_t nbytes, loff_t off)
373 {
374 struct resctrl_schema *s;
375 struct rdtgroup *rdtgrp;
376 struct rdt_resource *r;
377 char *tok, *resname;
378 int ret = 0;
379
380 /* Valid input requires a trailing newline */
381 if (nbytes == 0 || buf[nbytes - 1] != '\n')
382 return -EINVAL;
383 buf[nbytes - 1] = '\0';
384
385 cpus_read_lock();
386 rdtgrp = rdtgroup_kn_lock_live(of->kn);
387 if (!rdtgrp) {
388 rdtgroup_kn_unlock(of->kn);
389 cpus_read_unlock();
390 return -ENOENT;
391 }
392 rdt_last_cmd_clear();
393
394 /*
395 * No changes to pseudo-locked region allowed. It has to be removed
396 * and re-created instead.
397 */
398 if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
399 ret = -EINVAL;
400 rdt_last_cmd_puts("Resource group is pseudo-locked\n");
401 goto out;
402 }
403
404 rdt_staged_configs_clear();
405
406 while ((tok = strsep(&buf, "\n")) != NULL) {
407 resname = strim(strsep(&tok, ":"));
408 if (!tok) {
409 rdt_last_cmd_puts("Missing ':'\n");
410 ret = -EINVAL;
411 goto out;
412 }
413 if (tok[0] == '\0') {
414 rdt_last_cmd_printf("Missing '%s' value\n", resname);
415 ret = -EINVAL;
416 goto out;
417 }
418 ret = rdtgroup_parse_resource(resname, tok, rdtgrp);
419 if (ret)
420 goto out;
421 }
422
423 list_for_each_entry(s, &resctrl_schema_all, list) {
424 r = s->res;
425
426 /*
427 * Writes to mba_sc resources update the software controller,
428 * not the control MSR.
429 */
430 if (is_mba_sc(r))
431 continue;
432
433 ret = resctrl_arch_update_domains(r, rdtgrp->closid);
434 if (ret)
435 goto out;
436 }
437
438 if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
439 /*
440 * If pseudo-locking fails we keep the resource group in
441 * mode RDT_MODE_PSEUDO_LOCKSETUP with its class of service
442 * active and updated for just the domain the pseudo-locked
443 * region was requested for.
444 */
445 ret = rdtgroup_pseudo_lock_create(rdtgrp);
446 }
447
448 out:
449 rdt_staged_configs_clear();
450 rdtgroup_kn_unlock(of->kn);
451 cpus_read_unlock();
452 return ret ?: nbytes;
453 }
454
resctrl_arch_get_config(struct rdt_resource * r,struct rdt_domain * d,u32 closid,enum resctrl_conf_type type)455 u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,
456 u32 closid, enum resctrl_conf_type type)
457 {
458 struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
459 u32 idx = get_config_index(closid, type);
460
461 return hw_dom->ctrl_val[idx];
462 }
463
show_doms(struct seq_file * s,struct resctrl_schema * schema,int closid)464 static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int closid)
465 {
466 struct rdt_resource *r = schema->res;
467 struct rdt_domain *dom;
468 bool sep = false;
469 u32 ctrl_val;
470
471 seq_printf(s, "%*s:", max_name_width, schema->name);
472 list_for_each_entry(dom, &r->domains, list) {
473 if (sep)
474 seq_puts(s, ";");
475
476 if (is_mba_sc(r))
477 ctrl_val = dom->mbps_val[closid];
478 else
479 ctrl_val = resctrl_arch_get_config(r, dom, closid,
480 schema->conf_type);
481
482 seq_printf(s, r->format_str, dom->id, max_data_width,
483 ctrl_val);
484 sep = true;
485 }
486 seq_puts(s, "\n");
487 }
488
rdtgroup_schemata_show(struct kernfs_open_file * of,struct seq_file * s,void * v)489 int rdtgroup_schemata_show(struct kernfs_open_file *of,
490 struct seq_file *s, void *v)
491 {
492 struct resctrl_schema *schema;
493 struct rdtgroup *rdtgrp;
494 int ret = 0;
495 u32 closid;
496
497 rdtgrp = rdtgroup_kn_lock_live(of->kn);
498 if (rdtgrp) {
499 if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
500 list_for_each_entry(schema, &resctrl_schema_all, list) {
501 seq_printf(s, "%s:uninitialized\n", schema->name);
502 }
503 } else if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
504 if (!rdtgrp->plr->d) {
505 rdt_last_cmd_clear();
506 rdt_last_cmd_puts("Cache domain offline\n");
507 ret = -ENODEV;
508 } else {
509 seq_printf(s, "%s:%d=%x\n",
510 rdtgrp->plr->s->res->name,
511 rdtgrp->plr->d->id,
512 rdtgrp->plr->cbm);
513 }
514 } else {
515 closid = rdtgrp->closid;
516 list_for_each_entry(schema, &resctrl_schema_all, list) {
517 if (closid < schema->num_closid)
518 show_doms(s, schema, closid);
519 }
520 }
521 } else {
522 ret = -ENOENT;
523 }
524 rdtgroup_kn_unlock(of->kn);
525 return ret;
526 }
527
mon_event_read(struct rmid_read * rr,struct rdt_resource * r,struct rdt_domain * d,struct rdtgroup * rdtgrp,int evtid,int first)528 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
529 struct rdt_domain *d, struct rdtgroup *rdtgrp,
530 int evtid, int first)
531 {
532 /*
533 * setup the parameters to send to the IPI to read the data.
534 */
535 rr->rgrp = rdtgrp;
536 rr->evtid = evtid;
537 rr->r = r;
538 rr->d = d;
539 rr->val = 0;
540 rr->first = first;
541
542 smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);
543 }
544
rdtgroup_mondata_show(struct seq_file * m,void * arg)545 int rdtgroup_mondata_show(struct seq_file *m, void *arg)
546 {
547 struct kernfs_open_file *of = m->private;
548 u32 resid, evtid, domid;
549 struct rdtgroup *rdtgrp;
550 struct rdt_resource *r;
551 union mon_data_bits md;
552 struct rdt_domain *d;
553 struct rmid_read rr;
554 int ret = 0;
555
556 rdtgrp = rdtgroup_kn_lock_live(of->kn);
557 if (!rdtgrp) {
558 ret = -ENOENT;
559 goto out;
560 }
561
562 md.priv = of->kn->priv;
563 resid = md.u.rid;
564 domid = md.u.domid;
565 evtid = md.u.evtid;
566
567 r = &rdt_resources_all[resid].r_resctrl;
568 d = rdt_find_domain(r, domid, NULL);
569 if (IS_ERR_OR_NULL(d)) {
570 ret = -ENOENT;
571 goto out;
572 }
573
574 mon_event_read(&rr, r, d, rdtgrp, evtid, false);
575
576 if (rr.err == -EIO)
577 seq_puts(m, "Error\n");
578 else if (rr.err == -EINVAL)
579 seq_puts(m, "Unavailable\n");
580 else
581 seq_printf(m, "%llu\n", rr.val);
582
583 out:
584 rdtgroup_kn_unlock(of->kn);
585 return ret;
586 }
587