1/* 2 * Hypervisor supplied "24x7" performance counter support 3 * 4 * Author: Cody P Schafer <cody@linux.vnet.ibm.com> 5 * Copyright 2014 IBM Corporation. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13#define pr_fmt(fmt) "hv-24x7: " fmt 14 15#include <linux/perf_event.h> 16#include <linux/rbtree.h> 17#include <linux/module.h> 18#include <linux/slab.h> 19#include <linux/vmalloc.h> 20 21#include <asm/firmware.h> 22#include <asm/hvcall.h> 23#include <asm/io.h> 24#include <linux/byteorder/generic.h> 25 26#include "hv-24x7.h" 27#include "hv-24x7-catalog.h" 28#include "hv-common.h" 29 30static const char *event_domain_suffix(unsigned domain) 31{ 32 switch (domain) { 33#define DOMAIN(n, v, x, c) \ 34 case HV_PERF_DOMAIN_##n: \ 35 return "__" #n; 36#include "hv-24x7-domains.h" 37#undef DOMAIN 38 default: 39 WARN(1, "unknown domain %d\n", domain); 40 return "__UNKNOWN_DOMAIN_SUFFIX"; 41 } 42} 43 44static bool domain_is_valid(unsigned domain) 45{ 46 switch (domain) { 47#define DOMAIN(n, v, x, c) \ 48 case HV_PERF_DOMAIN_##n: \ 49 /* fall through */ 50#include "hv-24x7-domains.h" 51#undef DOMAIN 52 return true; 53 default: 54 return false; 55 } 56} 57 58static bool is_physical_domain(unsigned domain) 59{ 60 switch (domain) { 61#define DOMAIN(n, v, x, c) \ 62 case HV_PERF_DOMAIN_##n: \ 63 return c; 64#include "hv-24x7-domains.h" 65#undef DOMAIN 66 default: 67 return false; 68 } 69} 70 71static bool catalog_entry_domain_is_valid(unsigned domain) 72{ 73 return is_physical_domain(domain); 74} 75 76/* 77 * TODO: Merging events: 78 * - Think of the hcall as an interface to a 4d array of counters: 79 * - x = domains 80 * - y = indexes in the domain (core, chip, vcpu, node, etc) 81 * - z = offset into the counter space 82 * - w = lpars (guest vms, "logical partitions") 83 * - A single request is: x,y,y_last,z,z_last,w,w_last 84 * - this means we can retrieve a rectangle of counters in y,z for a single x. 85 * 86 * - Things to consider (ignoring w): 87 * - input cost_per_request = 16 88 * - output cost_per_result(ys,zs) = 8 + 8 * ys + ys * zs 89 * - limited number of requests per hcall (must fit into 4K bytes) 90 * - 4k = 16 [buffer header] - 16 [request size] * request_count 91 * - 255 requests per hcall 92 * - sometimes it will be more efficient to read extra data and discard 93 */ 94 95/* 96 * Example usage: 97 * perf stat -e 'hv_24x7/domain=2,offset=8,vcpu=0,lpar=0xffffffff/' 98 */ 99 100/* u3 0-6, one of HV_24X7_PERF_DOMAIN */ 101EVENT_DEFINE_RANGE_FORMAT(domain, config, 0, 3); 102/* u16 */ 103EVENT_DEFINE_RANGE_FORMAT(core, config, 16, 31); 104EVENT_DEFINE_RANGE_FORMAT(vcpu, config, 16, 31); 105/* u32, see "data_offset" */ 106EVENT_DEFINE_RANGE_FORMAT(offset, config, 32, 63); 107/* u16 */ 108EVENT_DEFINE_RANGE_FORMAT(lpar, config1, 0, 15); 109 110EVENT_DEFINE_RANGE(reserved1, config, 4, 15); 111EVENT_DEFINE_RANGE(reserved2, config1, 16, 63); 112EVENT_DEFINE_RANGE(reserved3, config2, 0, 63); 113 114static struct attribute *format_attrs[] = { 115 &format_attr_domain.attr, 116 &format_attr_offset.attr, 117 &format_attr_core.attr, 118 &format_attr_vcpu.attr, 119 &format_attr_lpar.attr, 120 NULL, 121}; 122 123static struct attribute_group format_group = { 124 .name = "format", 125 .attrs = format_attrs, 126}; 127 128static struct attribute_group event_group = { 129 .name = "events", 130 /* .attrs is set in init */ 131}; 132 133static struct attribute_group event_desc_group = { 134 .name = "event_descs", 135 /* .attrs is set in init */ 136}; 137 138static struct attribute_group event_long_desc_group = { 139 .name = "event_long_descs", 140 /* .attrs is set in init */ 141}; 142 143static struct kmem_cache *hv_page_cache; 144 145/* 146 * request_buffer and result_buffer are not required to be 4k aligned, 147 * but are not allowed to cross any 4k boundary. Aligning them to 4k is 148 * the simplest way to ensure that. 149 */ 150#define H24x7_DATA_BUFFER_SIZE 4096 151DEFINE_PER_CPU(char, hv_24x7_reqb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); 152DEFINE_PER_CPU(char, hv_24x7_resb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); 153 154static char *event_name(struct hv_24x7_event_data *ev, int *len) 155{ 156 *len = be16_to_cpu(ev->event_name_len) - 2; 157 return (char *)ev->remainder; 158} 159 160static char *event_desc(struct hv_24x7_event_data *ev, int *len) 161{ 162 unsigned nl = be16_to_cpu(ev->event_name_len); 163 __be16 *desc_len = (__be16 *)(ev->remainder + nl - 2); 164 165 *len = be16_to_cpu(*desc_len) - 2; 166 return (char *)ev->remainder + nl; 167} 168 169static char *event_long_desc(struct hv_24x7_event_data *ev, int *len) 170{ 171 unsigned nl = be16_to_cpu(ev->event_name_len); 172 __be16 *desc_len_ = (__be16 *)(ev->remainder + nl - 2); 173 unsigned desc_len = be16_to_cpu(*desc_len_); 174 __be16 *long_desc_len = (__be16 *)(ev->remainder + nl + desc_len - 2); 175 176 *len = be16_to_cpu(*long_desc_len) - 2; 177 return (char *)ev->remainder + nl + desc_len; 178} 179 180static bool event_fixed_portion_is_within(struct hv_24x7_event_data *ev, 181 void *end) 182{ 183 void *start = ev; 184 185 return (start + offsetof(struct hv_24x7_event_data, remainder)) < end; 186} 187 188/* 189 * Things we don't check: 190 * - padding for desc, name, and long/detailed desc is required to be '\0' 191 * bytes. 192 * 193 * Return NULL if we pass end, 194 * Otherwise return the address of the byte just following the event. 195 */ 196static void *event_end(struct hv_24x7_event_data *ev, void *end) 197{ 198 void *start = ev; 199 __be16 *dl_, *ldl_; 200 unsigned dl, ldl; 201 unsigned nl = be16_to_cpu(ev->event_name_len); 202 203 if (nl < 2) { 204 pr_debug("%s: name length too short: %d", __func__, nl); 205 return NULL; 206 } 207 208 if (start + nl > end) { 209 pr_debug("%s: start=%p + nl=%u > end=%p", 210 __func__, start, nl, end); 211 return NULL; 212 } 213 214 dl_ = (__be16 *)(ev->remainder + nl - 2); 215 if (!IS_ALIGNED((uintptr_t)dl_, 2)) 216 pr_warn("desc len not aligned %p", dl_); 217 dl = be16_to_cpu(*dl_); 218 if (dl < 2) { 219 pr_debug("%s: desc len too short: %d", __func__, dl); 220 return NULL; 221 } 222 223 if (start + nl + dl > end) { 224 pr_debug("%s: (start=%p + nl=%u + dl=%u)=%p > end=%p", 225 __func__, start, nl, dl, start + nl + dl, end); 226 return NULL; 227 } 228 229 ldl_ = (__be16 *)(ev->remainder + nl + dl - 2); 230 if (!IS_ALIGNED((uintptr_t)ldl_, 2)) 231 pr_warn("long desc len not aligned %p", ldl_); 232 ldl = be16_to_cpu(*ldl_); 233 if (ldl < 2) { 234 pr_debug("%s: long desc len too short (ldl=%u)", 235 __func__, ldl); 236 return NULL; 237 } 238 239 if (start + nl + dl + ldl > end) { 240 pr_debug("%s: start=%p + nl=%u + dl=%u + ldl=%u > end=%p", 241 __func__, start, nl, dl, ldl, end); 242 return NULL; 243 } 244 245 return start + nl + dl + ldl; 246} 247 248static unsigned long h_get_24x7_catalog_page_(unsigned long phys_4096, 249 unsigned long version, 250 unsigned long index) 251{ 252 pr_devel("h_get_24x7_catalog_page(0x%lx, %lu, %lu)", 253 phys_4096, version, index); 254 255 WARN_ON(!IS_ALIGNED(phys_4096, 4096)); 256 257 return plpar_hcall_norets(H_GET_24X7_CATALOG_PAGE, 258 phys_4096, version, index); 259} 260 261static unsigned long h_get_24x7_catalog_page(char page[], 262 u64 version, u32 index) 263{ 264 return h_get_24x7_catalog_page_(virt_to_phys(page), 265 version, index); 266} 267 268static unsigned core_domains[] = { 269 HV_PERF_DOMAIN_PHYS_CORE, 270 HV_PERF_DOMAIN_VCPU_HOME_CORE, 271 HV_PERF_DOMAIN_VCPU_HOME_CHIP, 272 HV_PERF_DOMAIN_VCPU_HOME_NODE, 273 HV_PERF_DOMAIN_VCPU_REMOTE_NODE, 274}; 275/* chip event data always yeilds a single event, core yeilds multiple */ 276#define MAX_EVENTS_PER_EVENT_DATA ARRAY_SIZE(core_domains) 277 278static char *event_fmt(struct hv_24x7_event_data *event, unsigned domain) 279{ 280 const char *sindex; 281 const char *lpar; 282 283 if (is_physical_domain(domain)) { 284 lpar = "0x0"; 285 sindex = "core"; 286 } else { 287 lpar = "?"; 288 sindex = "vcpu"; 289 } 290 291 return kasprintf(GFP_KERNEL, 292 "domain=0x%x,offset=0x%x,%s=?,lpar=%s", 293 domain, 294 be16_to_cpu(event->event_counter_offs) + 295 be16_to_cpu(event->event_group_record_offs), 296 sindex, 297 lpar); 298} 299 300/* Avoid trusting fw to NUL terminate strings */ 301static char *memdup_to_str(char *maybe_str, int max_len, gfp_t gfp) 302{ 303 return kasprintf(gfp, "%.*s", max_len, maybe_str); 304} 305 306static ssize_t device_show_string(struct device *dev, 307 struct device_attribute *attr, char *buf) 308{ 309 struct dev_ext_attribute *d; 310 311 d = container_of(attr, struct dev_ext_attribute, attr); 312 313 return sprintf(buf, "%s\n", (char *)d->var); 314} 315 316static struct attribute *device_str_attr_create_(char *name, char *str) 317{ 318 struct dev_ext_attribute *attr = kzalloc(sizeof(*attr), GFP_KERNEL); 319 320 if (!attr) 321 return NULL; 322 323 attr->var = str; 324 attr->attr.attr.name = name; 325 attr->attr.attr.mode = 0444; 326 attr->attr.show = device_show_string; 327 328 return &attr->attr.attr; 329} 330 331static struct attribute *device_str_attr_create(char *name, int name_max, 332 int name_nonce, 333 char *str, size_t str_max) 334{ 335 char *n; 336 char *s = memdup_to_str(str, str_max, GFP_KERNEL); 337 struct attribute *a; 338 339 if (!s) 340 return NULL; 341 342 if (!name_nonce) 343 n = kasprintf(GFP_KERNEL, "%.*s", name_max, name); 344 else 345 n = kasprintf(GFP_KERNEL, "%.*s__%d", name_max, name, 346 name_nonce); 347 if (!n) 348 goto out_s; 349 350 a = device_str_attr_create_(n, s); 351 if (!a) 352 goto out_n; 353 354 return a; 355out_n: 356 kfree(n); 357out_s: 358 kfree(s); 359 return NULL; 360} 361 362static void device_str_attr_destroy(struct attribute *attr) 363{ 364 struct dev_ext_attribute *d; 365 366 d = container_of(attr, struct dev_ext_attribute, attr.attr); 367 kfree(d->var); 368 kfree(d->attr.attr.name); 369 kfree(d); 370} 371 372static struct attribute *event_to_attr(unsigned ix, 373 struct hv_24x7_event_data *event, 374 unsigned domain, 375 int nonce) 376{ 377 int event_name_len; 378 char *ev_name, *a_ev_name, *val; 379 const char *ev_suffix; 380 struct attribute *attr; 381 382 if (!domain_is_valid(domain)) { 383 pr_warn("catalog event %u has invalid domain %u\n", 384 ix, domain); 385 return NULL; 386 } 387 388 val = event_fmt(event, domain); 389 if (!val) 390 return NULL; 391 392 ev_suffix = event_domain_suffix(domain); 393 ev_name = event_name(event, &event_name_len); 394 if (!nonce) 395 a_ev_name = kasprintf(GFP_KERNEL, "%.*s%s", 396 (int)event_name_len, ev_name, ev_suffix); 397 else 398 a_ev_name = kasprintf(GFP_KERNEL, "%.*s%s__%d", 399 (int)event_name_len, ev_name, ev_suffix, nonce); 400 401 if (!a_ev_name) 402 goto out_val; 403 404 attr = device_str_attr_create_(a_ev_name, val); 405 if (!attr) 406 goto out_name; 407 408 return attr; 409out_name: 410 kfree(a_ev_name); 411out_val: 412 kfree(val); 413 return NULL; 414} 415 416static struct attribute *event_to_desc_attr(struct hv_24x7_event_data *event, 417 int nonce) 418{ 419 int nl, dl; 420 char *name = event_name(event, &nl); 421 char *desc = event_desc(event, &dl); 422 423 /* If there isn't a description, don't create the sysfs file */ 424 if (!dl) 425 return NULL; 426 427 return device_str_attr_create(name, nl, nonce, desc, dl); 428} 429 430static struct attribute * 431event_to_long_desc_attr(struct hv_24x7_event_data *event, int nonce) 432{ 433 int nl, dl; 434 char *name = event_name(event, &nl); 435 char *desc = event_long_desc(event, &dl); 436 437 /* If there isn't a description, don't create the sysfs file */ 438 if (!dl) 439 return NULL; 440 441 return device_str_attr_create(name, nl, nonce, desc, dl); 442} 443 444static ssize_t event_data_to_attrs(unsigned ix, struct attribute **attrs, 445 struct hv_24x7_event_data *event, int nonce) 446{ 447 unsigned i; 448 449 switch (event->domain) { 450 case HV_PERF_DOMAIN_PHYS_CHIP: 451 *attrs = event_to_attr(ix, event, event->domain, nonce); 452 return 1; 453 case HV_PERF_DOMAIN_PHYS_CORE: 454 for (i = 0; i < ARRAY_SIZE(core_domains); i++) { 455 attrs[i] = event_to_attr(ix, event, core_domains[i], 456 nonce); 457 if (!attrs[i]) { 458 pr_warn("catalog event %u: individual attr %u " 459 "creation failure\n", ix, i); 460 for (; i; i--) 461 device_str_attr_destroy(attrs[i - 1]); 462 return -1; 463 } 464 } 465 return i; 466 default: 467 pr_warn("catalog event %u: domain %u is not allowed in the " 468 "catalog\n", ix, event->domain); 469 return -1; 470 } 471} 472 473static size_t event_to_attr_ct(struct hv_24x7_event_data *event) 474{ 475 switch (event->domain) { 476 case HV_PERF_DOMAIN_PHYS_CHIP: 477 return 1; 478 case HV_PERF_DOMAIN_PHYS_CORE: 479 return ARRAY_SIZE(core_domains); 480 default: 481 return 0; 482 } 483} 484 485static unsigned long vmalloc_to_phys(void *v) 486{ 487 struct page *p = vmalloc_to_page(v); 488 489 BUG_ON(!p); 490 return page_to_phys(p) + offset_in_page(v); 491} 492 493/* */ 494struct event_uniq { 495 struct rb_node node; 496 const char *name; 497 int nl; 498 unsigned ct; 499 unsigned domain; 500}; 501 502static int memord(const void *d1, size_t s1, const void *d2, size_t s2) 503{ 504 if (s1 < s2) 505 return 1; 506 if (s2 > s1) 507 return -1; 508 509 return memcmp(d1, d2, s1); 510} 511 512static int ev_uniq_ord(const void *v1, size_t s1, unsigned d1, const void *v2, 513 size_t s2, unsigned d2) 514{ 515 int r = memord(v1, s1, v2, s2); 516 517 if (r) 518 return r; 519 if (d1 > d2) 520 return 1; 521 if (d2 > d1) 522 return -1; 523 return 0; 524} 525 526static int event_uniq_add(struct rb_root *root, const char *name, int nl, 527 unsigned domain) 528{ 529 struct rb_node **new = &(root->rb_node), *parent = NULL; 530 struct event_uniq *data; 531 532 /* Figure out where to put new node */ 533 while (*new) { 534 struct event_uniq *it; 535 int result; 536 537 it = container_of(*new, struct event_uniq, node); 538 result = ev_uniq_ord(name, nl, domain, it->name, it->nl, 539 it->domain); 540 541 parent = *new; 542 if (result < 0) 543 new = &((*new)->rb_left); 544 else if (result > 0) 545 new = &((*new)->rb_right); 546 else { 547 it->ct++; 548 pr_info("found a duplicate event %.*s, ct=%u\n", nl, 549 name, it->ct); 550 return it->ct; 551 } 552 } 553 554 data = kmalloc(sizeof(*data), GFP_KERNEL); 555 if (!data) 556 return -ENOMEM; 557 558 *data = (struct event_uniq) { 559 .name = name, 560 .nl = nl, 561 .ct = 0, 562 .domain = domain, 563 }; 564 565 /* Add new node and rebalance tree. */ 566 rb_link_node(&data->node, parent, new); 567 rb_insert_color(&data->node, root); 568 569 /* data->ct */ 570 return 0; 571} 572 573static void event_uniq_destroy(struct rb_root *root) 574{ 575 /* 576 * the strings we point to are in the giant block of memory filled by 577 * the catalog, and are freed separately. 578 */ 579 struct event_uniq *pos, *n; 580 581 rbtree_postorder_for_each_entry_safe(pos, n, root, node) 582 kfree(pos); 583} 584 585 586/* 587 * ensure the event structure's sizes are self consistent and don't cause us to 588 * read outside of the event 589 * 590 * On success, return the event length in bytes. 591 * Otherwise, return -1 (and print as appropriate). 592 */ 593static ssize_t catalog_event_len_validate(struct hv_24x7_event_data *event, 594 size_t event_idx, 595 size_t event_data_bytes, 596 size_t event_entry_count, 597 size_t offset, void *end) 598{ 599 ssize_t ev_len; 600 void *ev_end, *calc_ev_end; 601 602 if (offset >= event_data_bytes) 603 return -1; 604 605 if (event_idx >= event_entry_count) { 606 pr_devel("catalog event data has %zu bytes of padding after last event\n", 607 event_data_bytes - offset); 608 return -1; 609 } 610 611 if (!event_fixed_portion_is_within(event, end)) { 612 pr_warn("event %zu fixed portion is not within range\n", 613 event_idx); 614 return -1; 615 } 616 617 ev_len = be16_to_cpu(event->length); 618 619 if (ev_len % 16) 620 pr_info("event %zu has length %zu not divisible by 16: event=%pK\n", 621 event_idx, ev_len, event); 622 623 ev_end = (__u8 *)event + ev_len; 624 if (ev_end > end) { 625 pr_warn("event %zu has .length=%zu, ends after buffer end: ev_end=%pK > end=%pK, offset=%zu\n", 626 event_idx, ev_len, ev_end, end, 627 offset); 628 return -1; 629 } 630 631 calc_ev_end = event_end(event, end); 632 if (!calc_ev_end) { 633 pr_warn("event %zu has a calculated length which exceeds buffer length %zu: event=%pK end=%pK, offset=%zu\n", 634 event_idx, event_data_bytes, event, end, 635 offset); 636 return -1; 637 } 638 639 if (calc_ev_end > ev_end) { 640 pr_warn("event %zu exceeds it's own length: event=%pK, end=%pK, offset=%zu, calc_ev_end=%pK\n", 641 event_idx, event, ev_end, offset, calc_ev_end); 642 return -1; 643 } 644 645 return ev_len; 646} 647 648#define MAX_4K (SIZE_MAX / 4096) 649 650static int create_events_from_catalog(struct attribute ***events_, 651 struct attribute ***event_descs_, 652 struct attribute ***event_long_descs_) 653{ 654 unsigned long hret; 655 size_t catalog_len, catalog_page_len, event_entry_count, 656 event_data_len, event_data_offs, 657 event_data_bytes, junk_events, event_idx, event_attr_ct, i, 658 attr_max, event_idx_last, desc_ct, long_desc_ct; 659 ssize_t ct, ev_len; 660 uint32_t catalog_version_num; 661 struct attribute **events, **event_descs, **event_long_descs; 662 struct hv_24x7_catalog_page_0 *page_0 = 663 kmem_cache_alloc(hv_page_cache, GFP_KERNEL); 664 void *page = page_0; 665 void *event_data, *end; 666 struct hv_24x7_event_data *event; 667 struct rb_root ev_uniq = RB_ROOT; 668 int ret = 0; 669 670 if (!page) { 671 ret = -ENOMEM; 672 goto e_out; 673 } 674 675 hret = h_get_24x7_catalog_page(page, 0, 0); 676 if (hret) { 677 ret = -EIO; 678 goto e_free; 679 } 680 681 catalog_version_num = be64_to_cpu(page_0->version); 682 catalog_page_len = be32_to_cpu(page_0->length); 683 684 if (MAX_4K < catalog_page_len) { 685 pr_err("invalid page count: %zu\n", catalog_page_len); 686 ret = -EIO; 687 goto e_free; 688 } 689 690 catalog_len = catalog_page_len * 4096; 691 692 event_entry_count = be16_to_cpu(page_0->event_entry_count); 693 event_data_offs = be16_to_cpu(page_0->event_data_offs); 694 event_data_len = be16_to_cpu(page_0->event_data_len); 695 696 pr_devel("cv %zu cl %zu eec %zu edo %zu edl %zu\n", 697 (size_t)catalog_version_num, catalog_len, 698 event_entry_count, event_data_offs, event_data_len); 699 700 if ((MAX_4K < event_data_len) 701 || (MAX_4K < event_data_offs) 702 || (MAX_4K - event_data_offs < event_data_len)) { 703 pr_err("invalid event data offs %zu and/or len %zu\n", 704 event_data_offs, event_data_len); 705 ret = -EIO; 706 goto e_free; 707 } 708 709 if ((event_data_offs + event_data_len) > catalog_page_len) { 710 pr_err("event data %zu-%zu does not fit inside catalog 0-%zu\n", 711 event_data_offs, 712 event_data_offs + event_data_len, 713 catalog_page_len); 714 ret = -EIO; 715 goto e_free; 716 } 717 718 if (SIZE_MAX / MAX_EVENTS_PER_EVENT_DATA - 1 < event_entry_count) { 719 pr_err("event_entry_count %zu is invalid\n", 720 event_entry_count); 721 ret = -EIO; 722 goto e_free; 723 } 724 725 event_data_bytes = event_data_len * 4096; 726 727 /* 728 * event data can span several pages, events can cross between these 729 * pages. Use vmalloc to make this easier. 730 */ 731 event_data = vmalloc(event_data_bytes); 732 if (!event_data) { 733 pr_err("could not allocate event data\n"); 734 ret = -ENOMEM; 735 goto e_free; 736 } 737 738 end = event_data + event_data_bytes; 739 740 /* 741 * using vmalloc_to_phys() like this only works if PAGE_SIZE is 742 * divisible by 4096 743 */ 744 BUILD_BUG_ON(PAGE_SIZE % 4096); 745 746 for (i = 0; i < event_data_len; i++) { 747 hret = h_get_24x7_catalog_page_( 748 vmalloc_to_phys(event_data + i * 4096), 749 catalog_version_num, 750 i + event_data_offs); 751 if (hret) { 752 pr_err("failed to get event data in page %zu\n", 753 i + event_data_offs); 754 ret = -EIO; 755 goto e_event_data; 756 } 757 } 758 759 /* 760 * scan the catalog to determine the number of attributes we need, and 761 * verify it at the same time. 762 */ 763 for (junk_events = 0, event = event_data, event_idx = 0, attr_max = 0; 764 ; 765 event_idx++, event = (void *)event + ev_len) { 766 size_t offset = (void *)event - (void *)event_data; 767 char *name; 768 int nl; 769 770 ev_len = catalog_event_len_validate(event, event_idx, 771 event_data_bytes, 772 event_entry_count, 773 offset, end); 774 if (ev_len < 0) 775 break; 776 777 name = event_name(event, &nl); 778 779 if (event->event_group_record_len == 0) { 780 pr_devel("invalid event %zu (%.*s): group_record_len == 0, skipping\n", 781 event_idx, nl, name); 782 junk_events++; 783 continue; 784 } 785 786 if (!catalog_entry_domain_is_valid(event->domain)) { 787 pr_info("event %zu (%.*s) has invalid domain %d\n", 788 event_idx, nl, name, event->domain); 789 junk_events++; 790 continue; 791 } 792 793 attr_max += event_to_attr_ct(event); 794 } 795 796 event_idx_last = event_idx; 797 if (event_idx_last != event_entry_count) 798 pr_warn("event buffer ended before listed # of events were parsed (got %zu, wanted %zu, junk %zu)\n", 799 event_idx_last, event_entry_count, junk_events); 800 801 events = kmalloc_array(attr_max + 1, sizeof(*events), GFP_KERNEL); 802 if (!events) { 803 ret = -ENOMEM; 804 goto e_event_data; 805 } 806 807 event_descs = kmalloc_array(event_idx + 1, sizeof(*event_descs), 808 GFP_KERNEL); 809 if (!event_descs) { 810 ret = -ENOMEM; 811 goto e_event_attrs; 812 } 813 814 event_long_descs = kmalloc_array(event_idx + 1, 815 sizeof(*event_long_descs), GFP_KERNEL); 816 if (!event_long_descs) { 817 ret = -ENOMEM; 818 goto e_event_descs; 819 } 820 821 /* Iterate over the catalog filling in the attribute vector */ 822 for (junk_events = 0, event_attr_ct = 0, desc_ct = 0, long_desc_ct = 0, 823 event = event_data, event_idx = 0; 824 event_idx < event_idx_last; 825 event_idx++, ev_len = be16_to_cpu(event->length), 826 event = (void *)event + ev_len) { 827 char *name; 828 int nl; 829 int nonce; 830 /* 831 * these are the only "bad" events that are intermixed and that 832 * we can ignore without issue. make sure to skip them here 833 */ 834 if (event->event_group_record_len == 0) 835 continue; 836 if (!catalog_entry_domain_is_valid(event->domain)) 837 continue; 838 839 name = event_name(event, &nl); 840 nonce = event_uniq_add(&ev_uniq, name, nl, event->domain); 841 ct = event_data_to_attrs(event_idx, events + event_attr_ct, 842 event, nonce); 843 if (ct <= 0) { 844 pr_warn("event %zu (%.*s) creation failure, skipping\n", 845 event_idx, nl, name); 846 junk_events++; 847 } else { 848 event_attr_ct += ct; 849 event_descs[desc_ct] = event_to_desc_attr(event, nonce); 850 if (event_descs[desc_ct]) 851 desc_ct++; 852 event_long_descs[long_desc_ct] = 853 event_to_long_desc_attr(event, nonce); 854 if (event_long_descs[long_desc_ct]) 855 long_desc_ct++; 856 } 857 } 858 859 pr_info("read %zu catalog entries, created %zu event attrs (%zu failures), %zu descs\n", 860 event_idx, event_attr_ct, junk_events, desc_ct); 861 862 events[event_attr_ct] = NULL; 863 event_descs[desc_ct] = NULL; 864 event_long_descs[long_desc_ct] = NULL; 865 866 event_uniq_destroy(&ev_uniq); 867 vfree(event_data); 868 kmem_cache_free(hv_page_cache, page); 869 870 *events_ = events; 871 *event_descs_ = event_descs; 872 *event_long_descs_ = event_long_descs; 873 return 0; 874 875e_event_descs: 876 kfree(event_descs); 877e_event_attrs: 878 kfree(events); 879e_event_data: 880 vfree(event_data); 881e_free: 882 kmem_cache_free(hv_page_cache, page); 883e_out: 884 *events_ = NULL; 885 *event_descs_ = NULL; 886 *event_long_descs_ = NULL; 887 return ret; 888} 889 890static ssize_t catalog_read(struct file *filp, struct kobject *kobj, 891 struct bin_attribute *bin_attr, char *buf, 892 loff_t offset, size_t count) 893{ 894 unsigned long hret; 895 ssize_t ret = 0; 896 size_t catalog_len = 0, catalog_page_len = 0; 897 loff_t page_offset = 0; 898 loff_t offset_in_page; 899 size_t copy_len; 900 uint64_t catalog_version_num = 0; 901 void *page = kmem_cache_alloc(hv_page_cache, GFP_USER); 902 struct hv_24x7_catalog_page_0 *page_0 = page; 903 904 if (!page) 905 return -ENOMEM; 906 907 hret = h_get_24x7_catalog_page(page, 0, 0); 908 if (hret) { 909 ret = -EIO; 910 goto e_free; 911 } 912 913 catalog_version_num = be64_to_cpu(page_0->version); 914 catalog_page_len = be32_to_cpu(page_0->length); 915 catalog_len = catalog_page_len * 4096; 916 917 page_offset = offset / 4096; 918 offset_in_page = offset % 4096; 919 920 if (page_offset >= catalog_page_len) 921 goto e_free; 922 923 if (page_offset != 0) { 924 hret = h_get_24x7_catalog_page(page, catalog_version_num, 925 page_offset); 926 if (hret) { 927 ret = -EIO; 928 goto e_free; 929 } 930 } 931 932 copy_len = 4096 - offset_in_page; 933 if (copy_len > count) 934 copy_len = count; 935 936 memcpy(buf, page+offset_in_page, copy_len); 937 ret = copy_len; 938 939e_free: 940 if (hret) 941 pr_err("h_get_24x7_catalog_page(ver=%lld, page=%lld) failed:" 942 " rc=%ld\n", 943 catalog_version_num, page_offset, hret); 944 kmem_cache_free(hv_page_cache, page); 945 946 pr_devel("catalog_read: offset=%lld(%lld) count=%zu " 947 "catalog_len=%zu(%zu) => %zd\n", offset, page_offset, 948 count, catalog_len, catalog_page_len, ret); 949 950 return ret; 951} 952 953#define PAGE_0_ATTR(_name, _fmt, _expr) \ 954static ssize_t _name##_show(struct device *dev, \ 955 struct device_attribute *dev_attr, \ 956 char *buf) \ 957{ \ 958 unsigned long hret; \ 959 ssize_t ret = 0; \ 960 void *page = kmem_cache_alloc(hv_page_cache, GFP_USER); \ 961 struct hv_24x7_catalog_page_0 *page_0 = page; \ 962 if (!page) \ 963 return -ENOMEM; \ 964 hret = h_get_24x7_catalog_page(page, 0, 0); \ 965 if (hret) { \ 966 ret = -EIO; \ 967 goto e_free; \ 968 } \ 969 ret = sprintf(buf, _fmt, _expr); \ 970e_free: \ 971 kmem_cache_free(hv_page_cache, page); \ 972 return ret; \ 973} \ 974static DEVICE_ATTR_RO(_name) 975 976PAGE_0_ATTR(catalog_version, "%lld\n", 977 (unsigned long long)be64_to_cpu(page_0->version)); 978PAGE_0_ATTR(catalog_len, "%lld\n", 979 (unsigned long long)be32_to_cpu(page_0->length) * 4096); 980static BIN_ATTR_RO(catalog, 0/* real length varies */); 981 982static struct bin_attribute *if_bin_attrs[] = { 983 &bin_attr_catalog, 984 NULL, 985}; 986 987static struct attribute *if_attrs[] = { 988 &dev_attr_catalog_len.attr, 989 &dev_attr_catalog_version.attr, 990 NULL, 991}; 992 993static struct attribute_group if_group = { 994 .name = "interface", 995 .bin_attrs = if_bin_attrs, 996 .attrs = if_attrs, 997}; 998 999static const struct attribute_group *attr_groups[] = { 1000 &format_group, 1001 &event_group, 1002 &event_desc_group, 1003 &event_long_desc_group, 1004 &if_group, 1005 NULL, 1006}; 1007 1008static void log_24x7_hcall(struct hv_24x7_request_buffer *request_buffer, 1009 struct hv_24x7_data_result_buffer *result_buffer, 1010 unsigned long ret) 1011{ 1012 struct hv_24x7_request *req; 1013 1014 req = &request_buffer->requests[0]; 1015 pr_notice_ratelimited("hcall failed: [%d %#x %#x %d] => " 1016 "ret 0x%lx (%ld) detail=0x%x failing ix=%x\n", 1017 req->performance_domain, req->data_offset, 1018 req->starting_ix, req->starting_lpar_ix, ret, ret, 1019 result_buffer->detailed_rc, 1020 result_buffer->failing_request_ix); 1021} 1022 1023/* 1024 * Start the process for a new H_GET_24x7_DATA hcall. 1025 */ 1026static void init_24x7_request(struct hv_24x7_request_buffer *request_buffer, 1027 struct hv_24x7_data_result_buffer *result_buffer) 1028{ 1029 1030 memset(request_buffer, 0, 4096); 1031 memset(result_buffer, 0, 4096); 1032 1033 request_buffer->interface_version = HV_24X7_IF_VERSION_CURRENT; 1034 /* memset above set request_buffer->num_requests to 0 */ 1035} 1036 1037/* 1038 * Commit (i.e perform) the H_GET_24x7_DATA hcall using the data collected 1039 * by 'init_24x7_request()' and 'add_event_to_24x7_request()'. 1040 */ 1041static int make_24x7_request(struct hv_24x7_request_buffer *request_buffer, 1042 struct hv_24x7_data_result_buffer *result_buffer) 1043{ 1044 unsigned long ret; 1045 1046 /* 1047 * NOTE: Due to variable number of array elements in request and 1048 * result buffer(s), sizeof() is not reliable. Use the actual 1049 * allocated buffer size, H24x7_DATA_BUFFER_SIZE. 1050 */ 1051 ret = plpar_hcall_norets(H_GET_24X7_DATA, 1052 virt_to_phys(request_buffer), H24x7_DATA_BUFFER_SIZE, 1053 virt_to_phys(result_buffer), H24x7_DATA_BUFFER_SIZE); 1054 1055 if (ret) 1056 log_24x7_hcall(request_buffer, result_buffer, ret); 1057 1058 return ret; 1059} 1060 1061/* 1062 * Add the given @event to the next slot in the 24x7 request_buffer. 1063 * 1064 * Note that H_GET_24X7_DATA hcall allows reading several counters' 1065 * values in a single HCALL. We expect the caller to add events to the 1066 * request buffer one by one, make the HCALL and process the results. 1067 */ 1068static int add_event_to_24x7_request(struct perf_event *event, 1069 struct hv_24x7_request_buffer *request_buffer) 1070{ 1071 u16 idx; 1072 int i; 1073 struct hv_24x7_request *req; 1074 1075 if (request_buffer->num_requests > 254) { 1076 pr_devel("Too many requests for 24x7 HCALL %d\n", 1077 request_buffer->num_requests); 1078 return -EINVAL; 1079 } 1080 1081 if (is_physical_domain(event_get_domain(event))) 1082 idx = event_get_core(event); 1083 else 1084 idx = event_get_vcpu(event); 1085 1086 i = request_buffer->num_requests++; 1087 req = &request_buffer->requests[i]; 1088 1089 req->performance_domain = event_get_domain(event); 1090 req->data_size = cpu_to_be16(8); 1091 req->data_offset = cpu_to_be32(event_get_offset(event)); 1092 req->starting_lpar_ix = cpu_to_be16(event_get_lpar(event)), 1093 req->max_num_lpars = cpu_to_be16(1); 1094 req->starting_ix = cpu_to_be16(idx); 1095 req->max_ix = cpu_to_be16(1); 1096 1097 return 0; 1098} 1099 1100static unsigned long single_24x7_request(struct perf_event *event, u64 *count) 1101{ 1102 unsigned long ret; 1103 struct hv_24x7_request_buffer *request_buffer; 1104 struct hv_24x7_data_result_buffer *result_buffer; 1105 struct hv_24x7_result *resb; 1106 1107 BUILD_BUG_ON(sizeof(*request_buffer) > 4096); 1108 BUILD_BUG_ON(sizeof(*result_buffer) > 4096); 1109 1110 request_buffer = (void *)get_cpu_var(hv_24x7_reqb); 1111 result_buffer = (void *)get_cpu_var(hv_24x7_resb); 1112 1113 init_24x7_request(request_buffer, result_buffer); 1114 1115 ret = add_event_to_24x7_request(event, request_buffer); 1116 if (ret) 1117 goto out; 1118 1119 ret = make_24x7_request(request_buffer, result_buffer); 1120 if (ret) { 1121 log_24x7_hcall(request_buffer, result_buffer, ret); 1122 goto out; 1123 } 1124 1125 /* process result from hcall */ 1126 resb = &result_buffer->results[0]; 1127 *count = be64_to_cpu(resb->elements[0].element_data[0]); 1128 1129out: 1130 put_cpu_var(hv_24x7_reqb); 1131 put_cpu_var(hv_24x7_resb); 1132 return ret; 1133} 1134 1135 1136static int h_24x7_event_init(struct perf_event *event) 1137{ 1138 struct hv_perf_caps caps; 1139 unsigned domain; 1140 unsigned long hret; 1141 u64 ct; 1142 1143 /* Not our event */ 1144 if (event->attr.type != event->pmu->type) 1145 return -ENOENT; 1146 1147 /* Unused areas must be 0 */ 1148 if (event_get_reserved1(event) || 1149 event_get_reserved2(event) || 1150 event_get_reserved3(event)) { 1151 pr_devel("reserved set when forbidden 0x%llx(0x%llx) 0x%llx(0x%llx) 0x%llx(0x%llx)\n", 1152 event->attr.config, 1153 event_get_reserved1(event), 1154 event->attr.config1, 1155 event_get_reserved2(event), 1156 event->attr.config2, 1157 event_get_reserved3(event)); 1158 return -EINVAL; 1159 } 1160 1161 /* unsupported modes and filters */ 1162 if (event->attr.exclude_user || 1163 event->attr.exclude_kernel || 1164 event->attr.exclude_hv || 1165 event->attr.exclude_idle || 1166 event->attr.exclude_host || 1167 event->attr.exclude_guest) 1168 return -EINVAL; 1169 1170 /* no branch sampling */ 1171 if (has_branch_stack(event)) 1172 return -EOPNOTSUPP; 1173 1174 /* offset must be 8 byte aligned */ 1175 if (event_get_offset(event) % 8) { 1176 pr_devel("bad alignment\n"); 1177 return -EINVAL; 1178 } 1179 1180 /* Domains above 6 are invalid */ 1181 domain = event_get_domain(event); 1182 if (domain > 6) { 1183 pr_devel("invalid domain %d\n", domain); 1184 return -EINVAL; 1185 } 1186 1187 hret = hv_perf_caps_get(&caps); 1188 if (hret) { 1189 pr_devel("could not get capabilities: rc=%ld\n", hret); 1190 return -EIO; 1191 } 1192 1193 /* Physical domains & other lpars require extra capabilities */ 1194 if (!caps.collect_privileged && (is_physical_domain(domain) || 1195 (event_get_lpar(event) != event_get_lpar_max()))) { 1196 pr_devel("hv permissions disallow: is_physical_domain:%d, lpar=0x%llx\n", 1197 is_physical_domain(domain), 1198 event_get_lpar(event)); 1199 return -EACCES; 1200 } 1201 1202 /* see if the event complains */ 1203 if (single_24x7_request(event, &ct)) { 1204 pr_devel("test hcall failed\n"); 1205 return -EIO; 1206 } 1207 1208 return 0; 1209} 1210 1211static u64 h_24x7_get_value(struct perf_event *event) 1212{ 1213 unsigned long ret; 1214 u64 ct; 1215 ret = single_24x7_request(event, &ct); 1216 if (ret) 1217 /* We checked this in event init, shouldn't fail here... */ 1218 return 0; 1219 1220 return ct; 1221} 1222 1223static void update_event_count(struct perf_event *event, u64 now) 1224{ 1225 s64 prev; 1226 1227 prev = local64_xchg(&event->hw.prev_count, now); 1228 local64_add(now - prev, &event->count); 1229} 1230 1231static void h_24x7_event_read(struct perf_event *event) 1232{ 1233 u64 now; 1234 1235 now = h_24x7_get_value(event); 1236 update_event_count(event, now); 1237} 1238 1239static void h_24x7_event_start(struct perf_event *event, int flags) 1240{ 1241 if (flags & PERF_EF_RELOAD) 1242 local64_set(&event->hw.prev_count, h_24x7_get_value(event)); 1243} 1244 1245static void h_24x7_event_stop(struct perf_event *event, int flags) 1246{ 1247 h_24x7_event_read(event); 1248} 1249 1250static int h_24x7_event_add(struct perf_event *event, int flags) 1251{ 1252 if (flags & PERF_EF_START) 1253 h_24x7_event_start(event, flags); 1254 1255 return 0; 1256} 1257 1258static struct pmu h_24x7_pmu = { 1259 .task_ctx_nr = perf_invalid_context, 1260 1261 .name = "hv_24x7", 1262 .attr_groups = attr_groups, 1263 .event_init = h_24x7_event_init, 1264 .add = h_24x7_event_add, 1265 .del = h_24x7_event_stop, 1266 .start = h_24x7_event_start, 1267 .stop = h_24x7_event_stop, 1268 .read = h_24x7_event_read, 1269}; 1270 1271static int hv_24x7_init(void) 1272{ 1273 int r; 1274 unsigned long hret; 1275 struct hv_perf_caps caps; 1276 1277 if (!firmware_has_feature(FW_FEATURE_LPAR)) { 1278 pr_debug("not a virtualized system, not enabling\n"); 1279 return -ENODEV; 1280 } 1281 1282 hret = hv_perf_caps_get(&caps); 1283 if (hret) { 1284 pr_debug("could not obtain capabilities, not enabling, rc=%ld\n", 1285 hret); 1286 return -ENODEV; 1287 } 1288 1289 hv_page_cache = kmem_cache_create("hv-page-4096", 4096, 4096, 0, NULL); 1290 if (!hv_page_cache) 1291 return -ENOMEM; 1292 1293 /* sampling not supported */ 1294 h_24x7_pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; 1295 1296 r = create_events_from_catalog(&event_group.attrs, 1297 &event_desc_group.attrs, 1298 &event_long_desc_group.attrs); 1299 1300 if (r) 1301 return r; 1302 1303 r = perf_pmu_register(&h_24x7_pmu, h_24x7_pmu.name, -1); 1304 if (r) 1305 return r; 1306 1307 return 0; 1308} 1309 1310device_initcall(hv_24x7_init); 1311