1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Hypervisor supplied "24x7" performance counter support 4 * 5 * Author: Cody P Schafer <cody@linux.vnet.ibm.com> 6 * Copyright 2014 IBM Corporation. 7 */ 8 9 #define pr_fmt(fmt) "hv-24x7: " fmt 10 11 #include <linux/perf_event.h> 12 #include <linux/rbtree.h> 13 #include <linux/module.h> 14 #include <linux/slab.h> 15 #include <linux/vmalloc.h> 16 17 #include <asm/cputhreads.h> 18 #include <asm/firmware.h> 19 #include <asm/hvcall.h> 20 #include <asm/io.h> 21 #include <linux/byteorder/generic.h> 22 23 #include "hv-24x7.h" 24 #include "hv-24x7-catalog.h" 25 #include "hv-common.h" 26 27 /* Version of the 24x7 hypervisor API that we should use in this machine. */ 28 static int interface_version; 29 30 /* Whether we have to aggregate result data for some domains. */ 31 static bool aggregate_result_elements; 32 33 static bool domain_is_valid(unsigned domain) 34 { 35 switch (domain) { 36 #define DOMAIN(n, v, x, c) \ 37 case HV_PERF_DOMAIN_##n: \ 38 /* fall through */ 39 #include "hv-24x7-domains.h" 40 #undef DOMAIN 41 return true; 42 default: 43 return false; 44 } 45 } 46 47 static bool is_physical_domain(unsigned domain) 48 { 49 switch (domain) { 50 #define DOMAIN(n, v, x, c) \ 51 case HV_PERF_DOMAIN_##n: \ 52 return c; 53 #include "hv-24x7-domains.h" 54 #undef DOMAIN 55 default: 56 return false; 57 } 58 } 59 60 /* Domains for which more than one result element are returned for each event. */ 61 static bool domain_needs_aggregation(unsigned int domain) 62 { 63 return aggregate_result_elements && 64 (domain == HV_PERF_DOMAIN_PHYS_CORE || 65 (domain >= HV_PERF_DOMAIN_VCPU_HOME_CORE && 66 domain <= HV_PERF_DOMAIN_VCPU_REMOTE_NODE)); 67 } 68 69 static const char *domain_name(unsigned domain) 70 { 71 if (!domain_is_valid(domain)) 72 return NULL; 73 74 switch (domain) { 75 case HV_PERF_DOMAIN_PHYS_CHIP: return "Physical Chip"; 76 case HV_PERF_DOMAIN_PHYS_CORE: return "Physical Core"; 77 case HV_PERF_DOMAIN_VCPU_HOME_CORE: return "VCPU Home Core"; 78 case HV_PERF_DOMAIN_VCPU_HOME_CHIP: return "VCPU Home Chip"; 79 case HV_PERF_DOMAIN_VCPU_HOME_NODE: return "VCPU Home Node"; 80 case HV_PERF_DOMAIN_VCPU_REMOTE_NODE: return "VCPU Remote Node"; 81 } 82 83 WARN_ON_ONCE(domain); 84 return NULL; 85 } 86 87 static bool catalog_entry_domain_is_valid(unsigned domain) 88 { 89 /* POWER8 doesn't support virtual domains. */ 90 if (interface_version == 1) 91 return is_physical_domain(domain); 92 else 93 return domain_is_valid(domain); 94 } 95 96 /* 97 * TODO: Merging events: 98 * - Think of the hcall as an interface to a 4d array of counters: 99 * - x = domains 100 * - y = indexes in the domain (core, chip, vcpu, node, etc) 101 * - z = offset into the counter space 102 * - w = lpars (guest vms, "logical partitions") 103 * - A single request is: x,y,y_last,z,z_last,w,w_last 104 * - this means we can retrieve a rectangle of counters in y,z for a single x. 105 * 106 * - Things to consider (ignoring w): 107 * - input cost_per_request = 16 108 * - output cost_per_result(ys,zs) = 8 + 8 * ys + ys * zs 109 * - limited number of requests per hcall (must fit into 4K bytes) 110 * - 4k = 16 [buffer header] - 16 [request size] * request_count 111 * - 255 requests per hcall 112 * - sometimes it will be more efficient to read extra data and discard 113 */ 114 115 /* 116 * Example usage: 117 * perf stat -e 'hv_24x7/domain=2,offset=8,vcpu=0,lpar=0xffffffff/' 118 */ 119 120 /* u3 0-6, one of HV_24X7_PERF_DOMAIN */ 121 EVENT_DEFINE_RANGE_FORMAT(domain, config, 0, 3); 122 /* u16 */ 123 EVENT_DEFINE_RANGE_FORMAT(core, config, 16, 31); 124 EVENT_DEFINE_RANGE_FORMAT(chip, config, 16, 31); 125 EVENT_DEFINE_RANGE_FORMAT(vcpu, config, 16, 31); 126 /* u32, see "data_offset" */ 127 EVENT_DEFINE_RANGE_FORMAT(offset, config, 32, 63); 128 /* u16 */ 129 EVENT_DEFINE_RANGE_FORMAT(lpar, config1, 0, 15); 130 131 EVENT_DEFINE_RANGE(reserved1, config, 4, 15); 132 EVENT_DEFINE_RANGE(reserved2, config1, 16, 63); 133 EVENT_DEFINE_RANGE(reserved3, config2, 0, 63); 134 135 static struct attribute *format_attrs[] = { 136 &format_attr_domain.attr, 137 &format_attr_offset.attr, 138 &format_attr_core.attr, 139 &format_attr_chip.attr, 140 &format_attr_vcpu.attr, 141 &format_attr_lpar.attr, 142 NULL, 143 }; 144 145 static struct attribute_group format_group = { 146 .name = "format", 147 .attrs = format_attrs, 148 }; 149 150 static struct attribute_group event_group = { 151 .name = "events", 152 /* .attrs is set in init */ 153 }; 154 155 static struct attribute_group event_desc_group = { 156 .name = "event_descs", 157 /* .attrs is set in init */ 158 }; 159 160 static struct attribute_group event_long_desc_group = { 161 .name = "event_long_descs", 162 /* .attrs is set in init */ 163 }; 164 165 static struct kmem_cache *hv_page_cache; 166 167 DEFINE_PER_CPU(int, hv_24x7_txn_flags); 168 DEFINE_PER_CPU(int, hv_24x7_txn_err); 169 170 struct hv_24x7_hw { 171 struct perf_event *events[255]; 172 }; 173 174 DEFINE_PER_CPU(struct hv_24x7_hw, hv_24x7_hw); 175 176 /* 177 * request_buffer and result_buffer are not required to be 4k aligned, 178 * but are not allowed to cross any 4k boundary. Aligning them to 4k is 179 * the simplest way to ensure that. 180 */ 181 #define H24x7_DATA_BUFFER_SIZE 4096 182 DEFINE_PER_CPU(char, hv_24x7_reqb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); 183 DEFINE_PER_CPU(char, hv_24x7_resb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); 184 185 static unsigned int max_num_requests(int interface_version) 186 { 187 return (H24x7_DATA_BUFFER_SIZE - sizeof(struct hv_24x7_request_buffer)) 188 / H24x7_REQUEST_SIZE(interface_version); 189 } 190 191 static char *event_name(struct hv_24x7_event_data *ev, int *len) 192 { 193 *len = be16_to_cpu(ev->event_name_len) - 2; 194 return (char *)ev->remainder; 195 } 196 197 static char *event_desc(struct hv_24x7_event_data *ev, int *len) 198 { 199 unsigned nl = be16_to_cpu(ev->event_name_len); 200 __be16 *desc_len = (__be16 *)(ev->remainder + nl - 2); 201 202 *len = be16_to_cpu(*desc_len) - 2; 203 return (char *)ev->remainder + nl; 204 } 205 206 static char *event_long_desc(struct hv_24x7_event_data *ev, int *len) 207 { 208 unsigned nl = be16_to_cpu(ev->event_name_len); 209 __be16 *desc_len_ = (__be16 *)(ev->remainder + nl - 2); 210 unsigned desc_len = be16_to_cpu(*desc_len_); 211 __be16 *long_desc_len = (__be16 *)(ev->remainder + nl + desc_len - 2); 212 213 *len = be16_to_cpu(*long_desc_len) - 2; 214 return (char *)ev->remainder + nl + desc_len; 215 } 216 217 static bool event_fixed_portion_is_within(struct hv_24x7_event_data *ev, 218 void *end) 219 { 220 void *start = ev; 221 222 return (start + offsetof(struct hv_24x7_event_data, remainder)) < end; 223 } 224 225 /* 226 * Things we don't check: 227 * - padding for desc, name, and long/detailed desc is required to be '\0' 228 * bytes. 229 * 230 * Return NULL if we pass end, 231 * Otherwise return the address of the byte just following the event. 232 */ 233 static void *event_end(struct hv_24x7_event_data *ev, void *end) 234 { 235 void *start = ev; 236 __be16 *dl_, *ldl_; 237 unsigned dl, ldl; 238 unsigned nl = be16_to_cpu(ev->event_name_len); 239 240 if (nl < 2) { 241 pr_debug("%s: name length too short: %d", __func__, nl); 242 return NULL; 243 } 244 245 if (start + nl > end) { 246 pr_debug("%s: start=%p + nl=%u > end=%p", 247 __func__, start, nl, end); 248 return NULL; 249 } 250 251 dl_ = (__be16 *)(ev->remainder + nl - 2); 252 if (!IS_ALIGNED((uintptr_t)dl_, 2)) 253 pr_warn("desc len not aligned %p", dl_); 254 dl = be16_to_cpu(*dl_); 255 if (dl < 2) { 256 pr_debug("%s: desc len too short: %d", __func__, dl); 257 return NULL; 258 } 259 260 if (start + nl + dl > end) { 261 pr_debug("%s: (start=%p + nl=%u + dl=%u)=%p > end=%p", 262 __func__, start, nl, dl, start + nl + dl, end); 263 return NULL; 264 } 265 266 ldl_ = (__be16 *)(ev->remainder + nl + dl - 2); 267 if (!IS_ALIGNED((uintptr_t)ldl_, 2)) 268 pr_warn("long desc len not aligned %p", ldl_); 269 ldl = be16_to_cpu(*ldl_); 270 if (ldl < 2) { 271 pr_debug("%s: long desc len too short (ldl=%u)", 272 __func__, ldl); 273 return NULL; 274 } 275 276 if (start + nl + dl + ldl > end) { 277 pr_debug("%s: start=%p + nl=%u + dl=%u + ldl=%u > end=%p", 278 __func__, start, nl, dl, ldl, end); 279 return NULL; 280 } 281 282 return start + nl + dl + ldl; 283 } 284 285 static long h_get_24x7_catalog_page_(unsigned long phys_4096, 286 unsigned long version, unsigned long index) 287 { 288 pr_devel("h_get_24x7_catalog_page(0x%lx, %lu, %lu)", 289 phys_4096, version, index); 290 291 WARN_ON(!IS_ALIGNED(phys_4096, 4096)); 292 293 return plpar_hcall_norets(H_GET_24X7_CATALOG_PAGE, 294 phys_4096, version, index); 295 } 296 297 static long h_get_24x7_catalog_page(char page[], u64 version, u32 index) 298 { 299 return h_get_24x7_catalog_page_(virt_to_phys(page), 300 version, index); 301 } 302 303 /* 304 * Each event we find in the catalog, will have a sysfs entry. Format the 305 * data for this sysfs entry based on the event's domain. 306 * 307 * Events belonging to the Chip domain can only be monitored in that domain. 308 * i.e the domain for these events is a fixed/knwon value. 309 * 310 * Events belonging to the Core domain can be monitored either in the physical 311 * core or in one of the virtual CPU domains. So the domain value for these 312 * events must be specified by the user (i.e is a required parameter). Format 313 * the Core events with 'domain=?' so the perf-tool can error check required 314 * parameters. 315 * 316 * NOTE: For the Core domain events, rather than making domain a required 317 * parameter we could default it to PHYS_CORE and allowe users to 318 * override the domain to one of the VCPU domains. 319 * 320 * However, this can make the interface a little inconsistent. 321 * 322 * If we set domain=2 (PHYS_CHIP) and allow user to override this field 323 * the user may be tempted to also modify the "offset=x" field in which 324 * can lead to confusing usage. Consider the HPM_PCYC (offset=0x18) and 325 * HPM_INST (offset=0x20) events. With: 326 * 327 * perf stat -e hv_24x7/HPM_PCYC,offset=0x20/ 328 * 329 * we end up monitoring HPM_INST, while the command line has HPM_PCYC. 330 * 331 * By not assigning a default value to the domain for the Core events, 332 * we can have simple guidelines: 333 * 334 * - Specifying values for parameters with "=?" is required. 335 * 336 * - Specifying (i.e overriding) values for other parameters 337 * is undefined. 338 */ 339 static char *event_fmt(struct hv_24x7_event_data *event, unsigned domain) 340 { 341 const char *sindex; 342 const char *lpar; 343 const char *domain_str; 344 char buf[8]; 345 346 switch (domain) { 347 case HV_PERF_DOMAIN_PHYS_CHIP: 348 snprintf(buf, sizeof(buf), "%d", domain); 349 domain_str = buf; 350 lpar = "0x0"; 351 sindex = "chip"; 352 break; 353 case HV_PERF_DOMAIN_PHYS_CORE: 354 domain_str = "?"; 355 lpar = "0x0"; 356 sindex = "core"; 357 break; 358 default: 359 domain_str = "?"; 360 lpar = "?"; 361 sindex = "vcpu"; 362 } 363 364 return kasprintf(GFP_KERNEL, 365 "domain=%s,offset=0x%x,%s=?,lpar=%s", 366 domain_str, 367 be16_to_cpu(event->event_counter_offs) + 368 be16_to_cpu(event->event_group_record_offs), 369 sindex, 370 lpar); 371 } 372 373 /* Avoid trusting fw to NUL terminate strings */ 374 static char *memdup_to_str(char *maybe_str, int max_len, gfp_t gfp) 375 { 376 return kasprintf(gfp, "%.*s", max_len, maybe_str); 377 } 378 379 static ssize_t device_show_string(struct device *dev, 380 struct device_attribute *attr, char *buf) 381 { 382 struct dev_ext_attribute *d; 383 384 d = container_of(attr, struct dev_ext_attribute, attr); 385 386 return sprintf(buf, "%s\n", (char *)d->var); 387 } 388 389 static struct attribute *device_str_attr_create_(char *name, char *str) 390 { 391 struct dev_ext_attribute *attr = kzalloc(sizeof(*attr), GFP_KERNEL); 392 393 if (!attr) 394 return NULL; 395 396 sysfs_attr_init(&attr->attr.attr); 397 398 attr->var = str; 399 attr->attr.attr.name = name; 400 attr->attr.attr.mode = 0444; 401 attr->attr.show = device_show_string; 402 403 return &attr->attr.attr; 404 } 405 406 /* 407 * Allocate and initialize strings representing event attributes. 408 * 409 * NOTE: The strings allocated here are never destroyed and continue to 410 * exist till shutdown. This is to allow us to create as many events 411 * from the catalog as possible, even if we encounter errors with some. 412 * In case of changes to error paths in future, these may need to be 413 * freed by the caller. 414 */ 415 static struct attribute *device_str_attr_create(char *name, int name_max, 416 int name_nonce, 417 char *str, size_t str_max) 418 { 419 char *n; 420 char *s = memdup_to_str(str, str_max, GFP_KERNEL); 421 struct attribute *a; 422 423 if (!s) 424 return NULL; 425 426 if (!name_nonce) 427 n = kasprintf(GFP_KERNEL, "%.*s", name_max, name); 428 else 429 n = kasprintf(GFP_KERNEL, "%.*s__%d", name_max, name, 430 name_nonce); 431 if (!n) 432 goto out_s; 433 434 a = device_str_attr_create_(n, s); 435 if (!a) 436 goto out_n; 437 438 return a; 439 out_n: 440 kfree(n); 441 out_s: 442 kfree(s); 443 return NULL; 444 } 445 446 static struct attribute *event_to_attr(unsigned ix, 447 struct hv_24x7_event_data *event, 448 unsigned domain, 449 int nonce) 450 { 451 int event_name_len; 452 char *ev_name, *a_ev_name, *val; 453 struct attribute *attr; 454 455 if (!domain_is_valid(domain)) { 456 pr_warn("catalog event %u has invalid domain %u\n", 457 ix, domain); 458 return NULL; 459 } 460 461 val = event_fmt(event, domain); 462 if (!val) 463 return NULL; 464 465 ev_name = event_name(event, &event_name_len); 466 if (!nonce) 467 a_ev_name = kasprintf(GFP_KERNEL, "%.*s", 468 (int)event_name_len, ev_name); 469 else 470 a_ev_name = kasprintf(GFP_KERNEL, "%.*s__%d", 471 (int)event_name_len, ev_name, nonce); 472 473 if (!a_ev_name) 474 goto out_val; 475 476 attr = device_str_attr_create_(a_ev_name, val); 477 if (!attr) 478 goto out_name; 479 480 return attr; 481 out_name: 482 kfree(a_ev_name); 483 out_val: 484 kfree(val); 485 return NULL; 486 } 487 488 static struct attribute *event_to_desc_attr(struct hv_24x7_event_data *event, 489 int nonce) 490 { 491 int nl, dl; 492 char *name = event_name(event, &nl); 493 char *desc = event_desc(event, &dl); 494 495 /* If there isn't a description, don't create the sysfs file */ 496 if (!dl) 497 return NULL; 498 499 return device_str_attr_create(name, nl, nonce, desc, dl); 500 } 501 502 static struct attribute * 503 event_to_long_desc_attr(struct hv_24x7_event_data *event, int nonce) 504 { 505 int nl, dl; 506 char *name = event_name(event, &nl); 507 char *desc = event_long_desc(event, &dl); 508 509 /* If there isn't a description, don't create the sysfs file */ 510 if (!dl) 511 return NULL; 512 513 return device_str_attr_create(name, nl, nonce, desc, dl); 514 } 515 516 static int event_data_to_attrs(unsigned ix, struct attribute **attrs, 517 struct hv_24x7_event_data *event, int nonce) 518 { 519 *attrs = event_to_attr(ix, event, event->domain, nonce); 520 if (!*attrs) 521 return -1; 522 523 return 0; 524 } 525 526 /* */ 527 struct event_uniq { 528 struct rb_node node; 529 const char *name; 530 int nl; 531 unsigned ct; 532 unsigned domain; 533 }; 534 535 static int memord(const void *d1, size_t s1, const void *d2, size_t s2) 536 { 537 if (s1 < s2) 538 return 1; 539 if (s1 > s2) 540 return -1; 541 542 return memcmp(d1, d2, s1); 543 } 544 545 static int ev_uniq_ord(const void *v1, size_t s1, unsigned d1, const void *v2, 546 size_t s2, unsigned d2) 547 { 548 int r = memord(v1, s1, v2, s2); 549 550 if (r) 551 return r; 552 if (d1 > d2) 553 return 1; 554 if (d2 > d1) 555 return -1; 556 return 0; 557 } 558 559 static int event_uniq_add(struct rb_root *root, const char *name, int nl, 560 unsigned domain) 561 { 562 struct rb_node **new = &(root->rb_node), *parent = NULL; 563 struct event_uniq *data; 564 565 /* Figure out where to put new node */ 566 while (*new) { 567 struct event_uniq *it; 568 int result; 569 570 it = rb_entry(*new, struct event_uniq, node); 571 result = ev_uniq_ord(name, nl, domain, it->name, it->nl, 572 it->domain); 573 574 parent = *new; 575 if (result < 0) 576 new = &((*new)->rb_left); 577 else if (result > 0) 578 new = &((*new)->rb_right); 579 else { 580 it->ct++; 581 pr_info("found a duplicate event %.*s, ct=%u\n", nl, 582 name, it->ct); 583 return it->ct; 584 } 585 } 586 587 data = kmalloc(sizeof(*data), GFP_KERNEL); 588 if (!data) 589 return -ENOMEM; 590 591 *data = (struct event_uniq) { 592 .name = name, 593 .nl = nl, 594 .ct = 0, 595 .domain = domain, 596 }; 597 598 /* Add new node and rebalance tree. */ 599 rb_link_node(&data->node, parent, new); 600 rb_insert_color(&data->node, root); 601 602 /* data->ct */ 603 return 0; 604 } 605 606 static void event_uniq_destroy(struct rb_root *root) 607 { 608 /* 609 * the strings we point to are in the giant block of memory filled by 610 * the catalog, and are freed separately. 611 */ 612 struct event_uniq *pos, *n; 613 614 rbtree_postorder_for_each_entry_safe(pos, n, root, node) 615 kfree(pos); 616 } 617 618 619 /* 620 * ensure the event structure's sizes are self consistent and don't cause us to 621 * read outside of the event 622 * 623 * On success, return the event length in bytes. 624 * Otherwise, return -1 (and print as appropriate). 625 */ 626 static ssize_t catalog_event_len_validate(struct hv_24x7_event_data *event, 627 size_t event_idx, 628 size_t event_data_bytes, 629 size_t event_entry_count, 630 size_t offset, void *end) 631 { 632 ssize_t ev_len; 633 void *ev_end, *calc_ev_end; 634 635 if (offset >= event_data_bytes) 636 return -1; 637 638 if (event_idx >= event_entry_count) { 639 pr_devel("catalog event data has %zu bytes of padding after last event\n", 640 event_data_bytes - offset); 641 return -1; 642 } 643 644 if (!event_fixed_portion_is_within(event, end)) { 645 pr_warn("event %zu fixed portion is not within range\n", 646 event_idx); 647 return -1; 648 } 649 650 ev_len = be16_to_cpu(event->length); 651 652 if (ev_len % 16) 653 pr_info("event %zu has length %zu not divisible by 16: event=%pK\n", 654 event_idx, ev_len, event); 655 656 ev_end = (__u8 *)event + ev_len; 657 if (ev_end > end) { 658 pr_warn("event %zu has .length=%zu, ends after buffer end: ev_end=%pK > end=%pK, offset=%zu\n", 659 event_idx, ev_len, ev_end, end, 660 offset); 661 return -1; 662 } 663 664 calc_ev_end = event_end(event, end); 665 if (!calc_ev_end) { 666 pr_warn("event %zu has a calculated length which exceeds buffer length %zu: event=%pK end=%pK, offset=%zu\n", 667 event_idx, event_data_bytes, event, end, 668 offset); 669 return -1; 670 } 671 672 if (calc_ev_end > ev_end) { 673 pr_warn("event %zu exceeds it's own length: event=%pK, end=%pK, offset=%zu, calc_ev_end=%pK\n", 674 event_idx, event, ev_end, offset, calc_ev_end); 675 return -1; 676 } 677 678 return ev_len; 679 } 680 681 #define MAX_4K (SIZE_MAX / 4096) 682 683 static int create_events_from_catalog(struct attribute ***events_, 684 struct attribute ***event_descs_, 685 struct attribute ***event_long_descs_) 686 { 687 long hret; 688 size_t catalog_len, catalog_page_len, event_entry_count, 689 event_data_len, event_data_offs, 690 event_data_bytes, junk_events, event_idx, event_attr_ct, i, 691 attr_max, event_idx_last, desc_ct, long_desc_ct; 692 ssize_t ct, ev_len; 693 uint64_t catalog_version_num; 694 struct attribute **events, **event_descs, **event_long_descs; 695 struct hv_24x7_catalog_page_0 *page_0 = 696 kmem_cache_alloc(hv_page_cache, GFP_KERNEL); 697 void *page = page_0; 698 void *event_data, *end; 699 struct hv_24x7_event_data *event; 700 struct rb_root ev_uniq = RB_ROOT; 701 int ret = 0; 702 703 if (!page) { 704 ret = -ENOMEM; 705 goto e_out; 706 } 707 708 hret = h_get_24x7_catalog_page(page, 0, 0); 709 if (hret) { 710 ret = -EIO; 711 goto e_free; 712 } 713 714 catalog_version_num = be64_to_cpu(page_0->version); 715 catalog_page_len = be32_to_cpu(page_0->length); 716 717 if (MAX_4K < catalog_page_len) { 718 pr_err("invalid page count: %zu\n", catalog_page_len); 719 ret = -EIO; 720 goto e_free; 721 } 722 723 catalog_len = catalog_page_len * 4096; 724 725 event_entry_count = be16_to_cpu(page_0->event_entry_count); 726 event_data_offs = be16_to_cpu(page_0->event_data_offs); 727 event_data_len = be16_to_cpu(page_0->event_data_len); 728 729 pr_devel("cv %llu cl %zu eec %zu edo %zu edl %zu\n", 730 catalog_version_num, catalog_len, 731 event_entry_count, event_data_offs, event_data_len); 732 733 if ((MAX_4K < event_data_len) 734 || (MAX_4K < event_data_offs) 735 || (MAX_4K - event_data_offs < event_data_len)) { 736 pr_err("invalid event data offs %zu and/or len %zu\n", 737 event_data_offs, event_data_len); 738 ret = -EIO; 739 goto e_free; 740 } 741 742 if ((event_data_offs + event_data_len) > catalog_page_len) { 743 pr_err("event data %zu-%zu does not fit inside catalog 0-%zu\n", 744 event_data_offs, 745 event_data_offs + event_data_len, 746 catalog_page_len); 747 ret = -EIO; 748 goto e_free; 749 } 750 751 if (SIZE_MAX - 1 < event_entry_count) { 752 pr_err("event_entry_count %zu is invalid\n", event_entry_count); 753 ret = -EIO; 754 goto e_free; 755 } 756 757 event_data_bytes = event_data_len * 4096; 758 759 /* 760 * event data can span several pages, events can cross between these 761 * pages. Use vmalloc to make this easier. 762 */ 763 event_data = vmalloc(event_data_bytes); 764 if (!event_data) { 765 pr_err("could not allocate event data\n"); 766 ret = -ENOMEM; 767 goto e_free; 768 } 769 770 end = event_data + event_data_bytes; 771 772 /* 773 * using vmalloc_to_phys() like this only works if PAGE_SIZE is 774 * divisible by 4096 775 */ 776 BUILD_BUG_ON(PAGE_SIZE % 4096); 777 778 for (i = 0; i < event_data_len; i++) { 779 hret = h_get_24x7_catalog_page_( 780 vmalloc_to_phys(event_data + i * 4096), 781 catalog_version_num, 782 i + event_data_offs); 783 if (hret) { 784 pr_err("Failed to get event data in page %zu: rc=%ld\n", 785 i + event_data_offs, hret); 786 ret = -EIO; 787 goto e_event_data; 788 } 789 } 790 791 /* 792 * scan the catalog to determine the number of attributes we need, and 793 * verify it at the same time. 794 */ 795 for (junk_events = 0, event = event_data, event_idx = 0, attr_max = 0; 796 ; 797 event_idx++, event = (void *)event + ev_len) { 798 size_t offset = (void *)event - (void *)event_data; 799 char *name; 800 int nl; 801 802 ev_len = catalog_event_len_validate(event, event_idx, 803 event_data_bytes, 804 event_entry_count, 805 offset, end); 806 if (ev_len < 0) 807 break; 808 809 name = event_name(event, &nl); 810 811 if (event->event_group_record_len == 0) { 812 pr_devel("invalid event %zu (%.*s): group_record_len == 0, skipping\n", 813 event_idx, nl, name); 814 junk_events++; 815 continue; 816 } 817 818 if (!catalog_entry_domain_is_valid(event->domain)) { 819 pr_info("event %zu (%.*s) has invalid domain %d\n", 820 event_idx, nl, name, event->domain); 821 junk_events++; 822 continue; 823 } 824 825 attr_max++; 826 } 827 828 event_idx_last = event_idx; 829 if (event_idx_last != event_entry_count) 830 pr_warn("event buffer ended before listed # of events were parsed (got %zu, wanted %zu, junk %zu)\n", 831 event_idx_last, event_entry_count, junk_events); 832 833 events = kmalloc_array(attr_max + 1, sizeof(*events), GFP_KERNEL); 834 if (!events) { 835 ret = -ENOMEM; 836 goto e_event_data; 837 } 838 839 event_descs = kmalloc_array(event_idx + 1, sizeof(*event_descs), 840 GFP_KERNEL); 841 if (!event_descs) { 842 ret = -ENOMEM; 843 goto e_event_attrs; 844 } 845 846 event_long_descs = kmalloc_array(event_idx + 1, 847 sizeof(*event_long_descs), GFP_KERNEL); 848 if (!event_long_descs) { 849 ret = -ENOMEM; 850 goto e_event_descs; 851 } 852 853 /* Iterate over the catalog filling in the attribute vector */ 854 for (junk_events = 0, event_attr_ct = 0, desc_ct = 0, long_desc_ct = 0, 855 event = event_data, event_idx = 0; 856 event_idx < event_idx_last; 857 event_idx++, ev_len = be16_to_cpu(event->length), 858 event = (void *)event + ev_len) { 859 char *name; 860 int nl; 861 int nonce; 862 /* 863 * these are the only "bad" events that are intermixed and that 864 * we can ignore without issue. make sure to skip them here 865 */ 866 if (event->event_group_record_len == 0) 867 continue; 868 if (!catalog_entry_domain_is_valid(event->domain)) 869 continue; 870 871 name = event_name(event, &nl); 872 nonce = event_uniq_add(&ev_uniq, name, nl, event->domain); 873 ct = event_data_to_attrs(event_idx, events + event_attr_ct, 874 event, nonce); 875 if (ct < 0) { 876 pr_warn("event %zu (%.*s) creation failure, skipping\n", 877 event_idx, nl, name); 878 junk_events++; 879 } else { 880 event_attr_ct++; 881 event_descs[desc_ct] = event_to_desc_attr(event, nonce); 882 if (event_descs[desc_ct]) 883 desc_ct++; 884 event_long_descs[long_desc_ct] = 885 event_to_long_desc_attr(event, nonce); 886 if (event_long_descs[long_desc_ct]) 887 long_desc_ct++; 888 } 889 } 890 891 pr_info("read %zu catalog entries, created %zu event attrs (%zu failures), %zu descs\n", 892 event_idx, event_attr_ct, junk_events, desc_ct); 893 894 events[event_attr_ct] = NULL; 895 event_descs[desc_ct] = NULL; 896 event_long_descs[long_desc_ct] = NULL; 897 898 event_uniq_destroy(&ev_uniq); 899 vfree(event_data); 900 kmem_cache_free(hv_page_cache, page); 901 902 *events_ = events; 903 *event_descs_ = event_descs; 904 *event_long_descs_ = event_long_descs; 905 return 0; 906 907 e_event_descs: 908 kfree(event_descs); 909 e_event_attrs: 910 kfree(events); 911 e_event_data: 912 vfree(event_data); 913 e_free: 914 kmem_cache_free(hv_page_cache, page); 915 e_out: 916 *events_ = NULL; 917 *event_descs_ = NULL; 918 *event_long_descs_ = NULL; 919 return ret; 920 } 921 922 static ssize_t catalog_read(struct file *filp, struct kobject *kobj, 923 struct bin_attribute *bin_attr, char *buf, 924 loff_t offset, size_t count) 925 { 926 long hret; 927 ssize_t ret = 0; 928 size_t catalog_len = 0, catalog_page_len = 0; 929 loff_t page_offset = 0; 930 loff_t offset_in_page; 931 size_t copy_len; 932 uint64_t catalog_version_num = 0; 933 void *page = kmem_cache_alloc(hv_page_cache, GFP_USER); 934 struct hv_24x7_catalog_page_0 *page_0 = page; 935 936 if (!page) 937 return -ENOMEM; 938 939 hret = h_get_24x7_catalog_page(page, 0, 0); 940 if (hret) { 941 ret = -EIO; 942 goto e_free; 943 } 944 945 catalog_version_num = be64_to_cpu(page_0->version); 946 catalog_page_len = be32_to_cpu(page_0->length); 947 catalog_len = catalog_page_len * 4096; 948 949 page_offset = offset / 4096; 950 offset_in_page = offset % 4096; 951 952 if (page_offset >= catalog_page_len) 953 goto e_free; 954 955 if (page_offset != 0) { 956 hret = h_get_24x7_catalog_page(page, catalog_version_num, 957 page_offset); 958 if (hret) { 959 ret = -EIO; 960 goto e_free; 961 } 962 } 963 964 copy_len = 4096 - offset_in_page; 965 if (copy_len > count) 966 copy_len = count; 967 968 memcpy(buf, page+offset_in_page, copy_len); 969 ret = copy_len; 970 971 e_free: 972 if (hret) 973 pr_err("h_get_24x7_catalog_page(ver=%lld, page=%lld) failed:" 974 " rc=%ld\n", 975 catalog_version_num, page_offset, hret); 976 kmem_cache_free(hv_page_cache, page); 977 978 pr_devel("catalog_read: offset=%lld(%lld) count=%zu " 979 "catalog_len=%zu(%zu) => %zd\n", offset, page_offset, 980 count, catalog_len, catalog_page_len, ret); 981 982 return ret; 983 } 984 985 static ssize_t domains_show(struct device *dev, struct device_attribute *attr, 986 char *page) 987 { 988 int d, n, count = 0; 989 const char *str; 990 991 for (d = 0; d < HV_PERF_DOMAIN_MAX; d++) { 992 str = domain_name(d); 993 if (!str) 994 continue; 995 996 n = sprintf(page, "%d: %s\n", d, str); 997 if (n < 0) 998 break; 999 1000 count += n; 1001 page += n; 1002 } 1003 return count; 1004 } 1005 1006 #define PAGE_0_ATTR(_name, _fmt, _expr) \ 1007 static ssize_t _name##_show(struct device *dev, \ 1008 struct device_attribute *dev_attr, \ 1009 char *buf) \ 1010 { \ 1011 long hret; \ 1012 ssize_t ret = 0; \ 1013 void *page = kmem_cache_alloc(hv_page_cache, GFP_USER); \ 1014 struct hv_24x7_catalog_page_0 *page_0 = page; \ 1015 if (!page) \ 1016 return -ENOMEM; \ 1017 hret = h_get_24x7_catalog_page(page, 0, 0); \ 1018 if (hret) { \ 1019 ret = -EIO; \ 1020 goto e_free; \ 1021 } \ 1022 ret = sprintf(buf, _fmt, _expr); \ 1023 e_free: \ 1024 kmem_cache_free(hv_page_cache, page); \ 1025 return ret; \ 1026 } \ 1027 static DEVICE_ATTR_RO(_name) 1028 1029 PAGE_0_ATTR(catalog_version, "%lld\n", 1030 (unsigned long long)be64_to_cpu(page_0->version)); 1031 PAGE_0_ATTR(catalog_len, "%lld\n", 1032 (unsigned long long)be32_to_cpu(page_0->length) * 4096); 1033 static BIN_ATTR_RO(catalog, 0/* real length varies */); 1034 static DEVICE_ATTR_RO(domains); 1035 1036 static struct bin_attribute *if_bin_attrs[] = { 1037 &bin_attr_catalog, 1038 NULL, 1039 }; 1040 1041 static struct attribute *if_attrs[] = { 1042 &dev_attr_catalog_len.attr, 1043 &dev_attr_catalog_version.attr, 1044 &dev_attr_domains.attr, 1045 NULL, 1046 }; 1047 1048 static struct attribute_group if_group = { 1049 .name = "interface", 1050 .bin_attrs = if_bin_attrs, 1051 .attrs = if_attrs, 1052 }; 1053 1054 static const struct attribute_group *attr_groups[] = { 1055 &format_group, 1056 &event_group, 1057 &event_desc_group, 1058 &event_long_desc_group, 1059 &if_group, 1060 NULL, 1061 }; 1062 1063 /* 1064 * Start the process for a new H_GET_24x7_DATA hcall. 1065 */ 1066 static void init_24x7_request(struct hv_24x7_request_buffer *request_buffer, 1067 struct hv_24x7_data_result_buffer *result_buffer) 1068 { 1069 1070 memset(request_buffer, 0, H24x7_DATA_BUFFER_SIZE); 1071 memset(result_buffer, 0, H24x7_DATA_BUFFER_SIZE); 1072 1073 request_buffer->interface_version = interface_version; 1074 /* memset above set request_buffer->num_requests to 0 */ 1075 } 1076 1077 /* 1078 * Commit (i.e perform) the H_GET_24x7_DATA hcall using the data collected 1079 * by 'init_24x7_request()' and 'add_event_to_24x7_request()'. 1080 */ 1081 static int make_24x7_request(struct hv_24x7_request_buffer *request_buffer, 1082 struct hv_24x7_data_result_buffer *result_buffer) 1083 { 1084 long ret; 1085 1086 /* 1087 * NOTE: Due to variable number of array elements in request and 1088 * result buffer(s), sizeof() is not reliable. Use the actual 1089 * allocated buffer size, H24x7_DATA_BUFFER_SIZE. 1090 */ 1091 ret = plpar_hcall_norets(H_GET_24X7_DATA, 1092 virt_to_phys(request_buffer), H24x7_DATA_BUFFER_SIZE, 1093 virt_to_phys(result_buffer), H24x7_DATA_BUFFER_SIZE); 1094 1095 if (ret) { 1096 struct hv_24x7_request *req; 1097 1098 req = request_buffer->requests; 1099 pr_notice_ratelimited("hcall failed: [%d %#x %#x %d] => ret 0x%lx (%ld) detail=0x%x failing ix=%x\n", 1100 req->performance_domain, req->data_offset, 1101 req->starting_ix, req->starting_lpar_ix, 1102 ret, ret, result_buffer->detailed_rc, 1103 result_buffer->failing_request_ix); 1104 return -EIO; 1105 } 1106 1107 return 0; 1108 } 1109 1110 /* 1111 * Add the given @event to the next slot in the 24x7 request_buffer. 1112 * 1113 * Note that H_GET_24X7_DATA hcall allows reading several counters' 1114 * values in a single HCALL. We expect the caller to add events to the 1115 * request buffer one by one, make the HCALL and process the results. 1116 */ 1117 static int add_event_to_24x7_request(struct perf_event *event, 1118 struct hv_24x7_request_buffer *request_buffer) 1119 { 1120 u16 idx; 1121 int i; 1122 size_t req_size; 1123 struct hv_24x7_request *req; 1124 1125 if (request_buffer->num_requests >= 1126 max_num_requests(request_buffer->interface_version)) { 1127 pr_devel("Too many requests for 24x7 HCALL %d\n", 1128 request_buffer->num_requests); 1129 return -EINVAL; 1130 } 1131 1132 switch (event_get_domain(event)) { 1133 case HV_PERF_DOMAIN_PHYS_CHIP: 1134 idx = event_get_chip(event); 1135 break; 1136 case HV_PERF_DOMAIN_PHYS_CORE: 1137 idx = event_get_core(event); 1138 break; 1139 default: 1140 idx = event_get_vcpu(event); 1141 } 1142 1143 req_size = H24x7_REQUEST_SIZE(request_buffer->interface_version); 1144 1145 i = request_buffer->num_requests++; 1146 req = (void *) request_buffer->requests + i * req_size; 1147 1148 req->performance_domain = event_get_domain(event); 1149 req->data_size = cpu_to_be16(8); 1150 req->data_offset = cpu_to_be32(event_get_offset(event)); 1151 req->starting_lpar_ix = cpu_to_be16(event_get_lpar(event)); 1152 req->max_num_lpars = cpu_to_be16(1); 1153 req->starting_ix = cpu_to_be16(idx); 1154 req->max_ix = cpu_to_be16(1); 1155 1156 if (request_buffer->interface_version > 1) { 1157 if (domain_needs_aggregation(req->performance_domain)) 1158 req->max_num_thread_groups = -1; 1159 else if (req->performance_domain != HV_PERF_DOMAIN_PHYS_CHIP) { 1160 req->starting_thread_group_ix = idx % 2; 1161 req->max_num_thread_groups = 1; 1162 } 1163 } 1164 1165 return 0; 1166 } 1167 1168 /** 1169 * get_count_from_result - get event count from all result elements in result 1170 * 1171 * If the event corresponding to this result needs aggregation of the result 1172 * element values, then this function does that. 1173 * 1174 * @event: Event associated with @res. 1175 * @resb: Result buffer containing @res. 1176 * @res: Result to work on. 1177 * @countp: Output variable containing the event count. 1178 * @next: Optional output variable pointing to the next result in @resb. 1179 */ 1180 static int get_count_from_result(struct perf_event *event, 1181 struct hv_24x7_data_result_buffer *resb, 1182 struct hv_24x7_result *res, u64 *countp, 1183 struct hv_24x7_result **next) 1184 { 1185 u16 num_elements = be16_to_cpu(res->num_elements_returned); 1186 u16 data_size = be16_to_cpu(res->result_element_data_size); 1187 unsigned int data_offset; 1188 void *element_data; 1189 int i; 1190 u64 count; 1191 1192 /* 1193 * We can bail out early if the result is empty. 1194 */ 1195 if (!num_elements) { 1196 pr_debug("Result of request %hhu is empty, nothing to do\n", 1197 res->result_ix); 1198 1199 if (next) 1200 *next = (struct hv_24x7_result *) res->elements; 1201 1202 return -ENODATA; 1203 } 1204 1205 /* 1206 * Since we always specify 1 as the maximum for the smallest resource 1207 * we're requesting, there should to be only one element per result. 1208 * Except when an event needs aggregation, in which case there are more. 1209 */ 1210 if (num_elements != 1 && 1211 !domain_needs_aggregation(event_get_domain(event))) { 1212 pr_err("Error: result of request %hhu has %hu elements\n", 1213 res->result_ix, num_elements); 1214 1215 return -EIO; 1216 } 1217 1218 if (data_size != sizeof(u64)) { 1219 pr_debug("Error: result of request %hhu has data of %hu bytes\n", 1220 res->result_ix, data_size); 1221 1222 return -ENOTSUPP; 1223 } 1224 1225 if (resb->interface_version == 1) 1226 data_offset = offsetof(struct hv_24x7_result_element_v1, 1227 element_data); 1228 else 1229 data_offset = offsetof(struct hv_24x7_result_element_v2, 1230 element_data); 1231 1232 /* Go through the result elements in the result. */ 1233 for (i = count = 0, element_data = res->elements + data_offset; 1234 i < num_elements; 1235 i++, element_data += data_size + data_offset) 1236 count += be64_to_cpu(*((u64 *) element_data)); 1237 1238 *countp = count; 1239 1240 /* The next result is after the last result element. */ 1241 if (next) 1242 *next = element_data - data_offset; 1243 1244 return 0; 1245 } 1246 1247 static int single_24x7_request(struct perf_event *event, u64 *count) 1248 { 1249 int ret; 1250 struct hv_24x7_request_buffer *request_buffer; 1251 struct hv_24x7_data_result_buffer *result_buffer; 1252 1253 BUILD_BUG_ON(sizeof(*request_buffer) > 4096); 1254 BUILD_BUG_ON(sizeof(*result_buffer) > 4096); 1255 1256 request_buffer = (void *)get_cpu_var(hv_24x7_reqb); 1257 result_buffer = (void *)get_cpu_var(hv_24x7_resb); 1258 1259 init_24x7_request(request_buffer, result_buffer); 1260 1261 ret = add_event_to_24x7_request(event, request_buffer); 1262 if (ret) 1263 goto out; 1264 1265 ret = make_24x7_request(request_buffer, result_buffer); 1266 if (ret) 1267 goto out; 1268 1269 /* process result from hcall */ 1270 ret = get_count_from_result(event, result_buffer, 1271 result_buffer->results, count, NULL); 1272 1273 out: 1274 put_cpu_var(hv_24x7_reqb); 1275 put_cpu_var(hv_24x7_resb); 1276 return ret; 1277 } 1278 1279 1280 static int h_24x7_event_init(struct perf_event *event) 1281 { 1282 struct hv_perf_caps caps; 1283 unsigned domain; 1284 unsigned long hret; 1285 u64 ct; 1286 1287 /* Not our event */ 1288 if (event->attr.type != event->pmu->type) 1289 return -ENOENT; 1290 1291 /* Unused areas must be 0 */ 1292 if (event_get_reserved1(event) || 1293 event_get_reserved2(event) || 1294 event_get_reserved3(event)) { 1295 pr_devel("reserved set when forbidden 0x%llx(0x%llx) 0x%llx(0x%llx) 0x%llx(0x%llx)\n", 1296 event->attr.config, 1297 event_get_reserved1(event), 1298 event->attr.config1, 1299 event_get_reserved2(event), 1300 event->attr.config2, 1301 event_get_reserved3(event)); 1302 return -EINVAL; 1303 } 1304 1305 /* no branch sampling */ 1306 if (has_branch_stack(event)) 1307 return -EOPNOTSUPP; 1308 1309 /* offset must be 8 byte aligned */ 1310 if (event_get_offset(event) % 8) { 1311 pr_devel("bad alignment\n"); 1312 return -EINVAL; 1313 } 1314 1315 domain = event_get_domain(event); 1316 if (domain >= HV_PERF_DOMAIN_MAX) { 1317 pr_devel("invalid domain %d\n", domain); 1318 return -EINVAL; 1319 } 1320 1321 hret = hv_perf_caps_get(&caps); 1322 if (hret) { 1323 pr_devel("could not get capabilities: rc=%ld\n", hret); 1324 return -EIO; 1325 } 1326 1327 /* Physical domains & other lpars require extra capabilities */ 1328 if (!caps.collect_privileged && (is_physical_domain(domain) || 1329 (event_get_lpar(event) != event_get_lpar_max()))) { 1330 pr_devel("hv permissions disallow: is_physical_domain:%d, lpar=0x%llx\n", 1331 is_physical_domain(domain), 1332 event_get_lpar(event)); 1333 return -EACCES; 1334 } 1335 1336 /* Get the initial value of the counter for this event */ 1337 if (single_24x7_request(event, &ct)) { 1338 pr_devel("test hcall failed\n"); 1339 return -EIO; 1340 } 1341 (void)local64_xchg(&event->hw.prev_count, ct); 1342 1343 return 0; 1344 } 1345 1346 static u64 h_24x7_get_value(struct perf_event *event) 1347 { 1348 u64 ct; 1349 1350 if (single_24x7_request(event, &ct)) 1351 /* We checked this in event init, shouldn't fail here... */ 1352 return 0; 1353 1354 return ct; 1355 } 1356 1357 static void update_event_count(struct perf_event *event, u64 now) 1358 { 1359 s64 prev; 1360 1361 prev = local64_xchg(&event->hw.prev_count, now); 1362 local64_add(now - prev, &event->count); 1363 } 1364 1365 static void h_24x7_event_read(struct perf_event *event) 1366 { 1367 u64 now; 1368 struct hv_24x7_request_buffer *request_buffer; 1369 struct hv_24x7_hw *h24x7hw; 1370 int txn_flags; 1371 1372 txn_flags = __this_cpu_read(hv_24x7_txn_flags); 1373 1374 /* 1375 * If in a READ transaction, add this counter to the list of 1376 * counters to read during the next HCALL (i.e commit_txn()). 1377 * If not in a READ transaction, go ahead and make the HCALL 1378 * to read this counter by itself. 1379 */ 1380 1381 if (txn_flags & PERF_PMU_TXN_READ) { 1382 int i; 1383 int ret; 1384 1385 if (__this_cpu_read(hv_24x7_txn_err)) 1386 return; 1387 1388 request_buffer = (void *)get_cpu_var(hv_24x7_reqb); 1389 1390 ret = add_event_to_24x7_request(event, request_buffer); 1391 if (ret) { 1392 __this_cpu_write(hv_24x7_txn_err, ret); 1393 } else { 1394 /* 1395 * Associate the event with the HCALL request index, 1396 * so ->commit_txn() can quickly find/update count. 1397 */ 1398 i = request_buffer->num_requests - 1; 1399 1400 h24x7hw = &get_cpu_var(hv_24x7_hw); 1401 h24x7hw->events[i] = event; 1402 put_cpu_var(h24x7hw); 1403 /* 1404 * Clear the event count so we can compute the _change_ 1405 * in the 24x7 raw counter value at the end of the txn. 1406 * 1407 * Note that we could alternatively read the 24x7 value 1408 * now and save its value in event->hw.prev_count. But 1409 * that would require issuing a hcall, which would then 1410 * defeat the purpose of using the txn interface. 1411 */ 1412 local64_set(&event->count, 0); 1413 } 1414 1415 put_cpu_var(hv_24x7_reqb); 1416 } else { 1417 now = h_24x7_get_value(event); 1418 update_event_count(event, now); 1419 } 1420 } 1421 1422 static void h_24x7_event_start(struct perf_event *event, int flags) 1423 { 1424 if (flags & PERF_EF_RELOAD) 1425 local64_set(&event->hw.prev_count, h_24x7_get_value(event)); 1426 } 1427 1428 static void h_24x7_event_stop(struct perf_event *event, int flags) 1429 { 1430 h_24x7_event_read(event); 1431 } 1432 1433 static int h_24x7_event_add(struct perf_event *event, int flags) 1434 { 1435 if (flags & PERF_EF_START) 1436 h_24x7_event_start(event, flags); 1437 1438 return 0; 1439 } 1440 1441 /* 1442 * 24x7 counters only support READ transactions. They are 1443 * always counting and dont need/support ADD transactions. 1444 * Cache the flags, but otherwise ignore transactions that 1445 * are not PERF_PMU_TXN_READ. 1446 */ 1447 static void h_24x7_event_start_txn(struct pmu *pmu, unsigned int flags) 1448 { 1449 struct hv_24x7_request_buffer *request_buffer; 1450 struct hv_24x7_data_result_buffer *result_buffer; 1451 1452 /* We should not be called if we are already in a txn */ 1453 WARN_ON_ONCE(__this_cpu_read(hv_24x7_txn_flags)); 1454 1455 __this_cpu_write(hv_24x7_txn_flags, flags); 1456 if (flags & ~PERF_PMU_TXN_READ) 1457 return; 1458 1459 request_buffer = (void *)get_cpu_var(hv_24x7_reqb); 1460 result_buffer = (void *)get_cpu_var(hv_24x7_resb); 1461 1462 init_24x7_request(request_buffer, result_buffer); 1463 1464 put_cpu_var(hv_24x7_resb); 1465 put_cpu_var(hv_24x7_reqb); 1466 } 1467 1468 /* 1469 * Clean up transaction state. 1470 * 1471 * NOTE: Ignore state of request and result buffers for now. 1472 * We will initialize them during the next read/txn. 1473 */ 1474 static void reset_txn(void) 1475 { 1476 __this_cpu_write(hv_24x7_txn_flags, 0); 1477 __this_cpu_write(hv_24x7_txn_err, 0); 1478 } 1479 1480 /* 1481 * 24x7 counters only support READ transactions. They are always counting 1482 * and dont need/support ADD transactions. Clear ->txn_flags but otherwise 1483 * ignore transactions that are not of type PERF_PMU_TXN_READ. 1484 * 1485 * For READ transactions, submit all pending 24x7 requests (i.e requests 1486 * that were queued by h_24x7_event_read()), to the hypervisor and update 1487 * the event counts. 1488 */ 1489 static int h_24x7_event_commit_txn(struct pmu *pmu) 1490 { 1491 struct hv_24x7_request_buffer *request_buffer; 1492 struct hv_24x7_data_result_buffer *result_buffer; 1493 struct hv_24x7_result *res, *next_res; 1494 u64 count; 1495 int i, ret, txn_flags; 1496 struct hv_24x7_hw *h24x7hw; 1497 1498 txn_flags = __this_cpu_read(hv_24x7_txn_flags); 1499 WARN_ON_ONCE(!txn_flags); 1500 1501 ret = 0; 1502 if (txn_flags & ~PERF_PMU_TXN_READ) 1503 goto out; 1504 1505 ret = __this_cpu_read(hv_24x7_txn_err); 1506 if (ret) 1507 goto out; 1508 1509 request_buffer = (void *)get_cpu_var(hv_24x7_reqb); 1510 result_buffer = (void *)get_cpu_var(hv_24x7_resb); 1511 1512 ret = make_24x7_request(request_buffer, result_buffer); 1513 if (ret) 1514 goto put_reqb; 1515 1516 h24x7hw = &get_cpu_var(hv_24x7_hw); 1517 1518 /* Go through results in the result buffer to update event counts. */ 1519 for (i = 0, res = result_buffer->results; 1520 i < result_buffer->num_results; i++, res = next_res) { 1521 struct perf_event *event = h24x7hw->events[res->result_ix]; 1522 1523 ret = get_count_from_result(event, result_buffer, res, &count, 1524 &next_res); 1525 if (ret) 1526 break; 1527 1528 update_event_count(event, count); 1529 } 1530 1531 put_cpu_var(hv_24x7_hw); 1532 1533 put_reqb: 1534 put_cpu_var(hv_24x7_resb); 1535 put_cpu_var(hv_24x7_reqb); 1536 out: 1537 reset_txn(); 1538 return ret; 1539 } 1540 1541 /* 1542 * 24x7 counters only support READ transactions. They are always counting 1543 * and dont need/support ADD transactions. However, regardless of type 1544 * of transaction, all we need to do is cleanup, so we don't have to check 1545 * the type of transaction. 1546 */ 1547 static void h_24x7_event_cancel_txn(struct pmu *pmu) 1548 { 1549 WARN_ON_ONCE(!__this_cpu_read(hv_24x7_txn_flags)); 1550 reset_txn(); 1551 } 1552 1553 static struct pmu h_24x7_pmu = { 1554 .task_ctx_nr = perf_invalid_context, 1555 1556 .name = "hv_24x7", 1557 .attr_groups = attr_groups, 1558 .event_init = h_24x7_event_init, 1559 .add = h_24x7_event_add, 1560 .del = h_24x7_event_stop, 1561 .start = h_24x7_event_start, 1562 .stop = h_24x7_event_stop, 1563 .read = h_24x7_event_read, 1564 .start_txn = h_24x7_event_start_txn, 1565 .commit_txn = h_24x7_event_commit_txn, 1566 .cancel_txn = h_24x7_event_cancel_txn, 1567 .capabilities = PERF_PMU_CAP_NO_EXCLUDE, 1568 }; 1569 1570 static int hv_24x7_init(void) 1571 { 1572 int r; 1573 unsigned long hret; 1574 struct hv_perf_caps caps; 1575 1576 if (!firmware_has_feature(FW_FEATURE_LPAR)) { 1577 pr_debug("not a virtualized system, not enabling\n"); 1578 return -ENODEV; 1579 } else if (!cur_cpu_spec->oprofile_cpu_type) 1580 return -ENODEV; 1581 1582 /* POWER8 only supports v1, while POWER9 only supports v2. */ 1583 if (!strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power8")) 1584 interface_version = 1; 1585 else { 1586 interface_version = 2; 1587 1588 /* SMT8 in POWER9 needs to aggregate result elements. */ 1589 if (threads_per_core == 8) 1590 aggregate_result_elements = true; 1591 } 1592 1593 hret = hv_perf_caps_get(&caps); 1594 if (hret) { 1595 pr_debug("could not obtain capabilities, not enabling, rc=%ld\n", 1596 hret); 1597 return -ENODEV; 1598 } 1599 1600 hv_page_cache = kmem_cache_create("hv-page-4096", 4096, 4096, 0, NULL); 1601 if (!hv_page_cache) 1602 return -ENOMEM; 1603 1604 /* sampling not supported */ 1605 h_24x7_pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; 1606 1607 r = create_events_from_catalog(&event_group.attrs, 1608 &event_desc_group.attrs, 1609 &event_long_desc_group.attrs); 1610 1611 if (r) 1612 return r; 1613 1614 r = perf_pmu_register(&h_24x7_pmu, h_24x7_pmu.name, -1); 1615 if (r) 1616 return r; 1617 1618 return 0; 1619 } 1620 1621 device_initcall(hv_24x7_init); 1622