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