Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 | /*
* User interface for Resource Alloction in Resource Director Technology(RDT)
*
* Copyright (C) 2016 Intel Corporation
*
* Author: Fenghua Yu <fenghua.yu@intel.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* More information about RDT be found in the Intel (R) x86 Architecture
* Software Developer Manual.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/cpu.h>
#include <linux/fs.h>
#include <linux/sysfs.h>
#include <linux/kernfs.h>
#include <linux/seq_buf.h>
#include <linux/seq_file.h>
#include <linux/sched/signal.h>
#include <linux/sched/task.h>
#include <linux/slab.h>
#include <linux/task_work.h>
#include <uapi/linux/magic.h>
#include <asm/intel_rdt_sched.h>
#include "intel_rdt.h"
DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
DEFINE_STATIC_KEY_FALSE(rdt_mon_enable_key);
DEFINE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
static struct kernfs_root *rdt_root;
struct rdtgroup rdtgroup_default;
LIST_HEAD(rdt_all_groups);
/* Kernel fs node for "info" directory under root */
static struct kernfs_node *kn_info;
/* Kernel fs node for "mon_groups" directory under root */
static struct kernfs_node *kn_mongrp;
/* Kernel fs node for "mon_data" directory under root */
static struct kernfs_node *kn_mondata;
static struct seq_buf last_cmd_status;
static char last_cmd_status_buf[512];
void rdt_last_cmd_clear(void)
{
lockdep_assert_held(&rdtgroup_mutex);
seq_buf_clear(&last_cmd_status);
}
void rdt_last_cmd_puts(const char *s)
{
lockdep_assert_held(&rdtgroup_mutex);
seq_buf_puts(&last_cmd_status, s);
}
void rdt_last_cmd_printf(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
lockdep_assert_held(&rdtgroup_mutex);
seq_buf_vprintf(&last_cmd_status, fmt, ap);
va_end(ap);
}
/*
* Trivial allocator for CLOSIDs. Since h/w only supports a small number,
* we can keep a bitmap of free CLOSIDs in a single integer.
*
* Using a global CLOSID across all resources has some advantages and
* some drawbacks:
* + We can simply set "current->closid" to assign a task to a resource
* group.
* + Context switch code can avoid extra memory references deciding which
* CLOSID to load into the PQR_ASSOC MSR
* - We give up some options in configuring resource groups across multi-socket
* systems.
* - Our choices on how to configure each resource become progressively more
* limited as the number of resources grows.
*/
static int closid_free_map;
static void closid_init(void)
{
struct rdt_resource *r;
int rdt_min_closid = 32;
/* Compute rdt_min_closid across all resources */
for_each_alloc_enabled_rdt_resource(r)
rdt_min_closid = min(rdt_min_closid, r->num_closid);
closid_free_map = BIT_MASK(rdt_min_closid) - 1;
/* CLOSID 0 is always reserved for the default group */
closid_free_map &= ~1;
}
static int closid_alloc(void)
{
u32 closid = ffs(closid_free_map);
if (closid == 0)
return -ENOSPC;
closid--;
closid_free_map &= ~(1 << closid);
return closid;
}
static void closid_free(int closid)
{
closid_free_map |= 1 << closid;
}
/* set uid and gid of rdtgroup dirs and files to that of the creator */
static int rdtgroup_kn_set_ugid(struct kernfs_node *kn)
{
struct iattr iattr = { .ia_valid = ATTR_UID | ATTR_GID,
.ia_uid = current_fsuid(),
.ia_gid = current_fsgid(), };
if (uid_eq(iattr.ia_uid, GLOBAL_ROOT_UID) &&
gid_eq(iattr.ia_gid, GLOBAL_ROOT_GID))
return 0;
return kernfs_setattr(kn, &iattr);
}
static int rdtgroup_add_file(struct kernfs_node *parent_kn, struct rftype *rft)
{
struct kernfs_node *kn;
int ret;
kn = __kernfs_create_file(parent_kn, rft->name, rft->mode,
0, rft->kf_ops, rft, NULL, NULL);
if (IS_ERR(kn))
return PTR_ERR(kn);
ret = rdtgroup_kn_set_ugid(kn);
if (ret) {
kernfs_remove(kn);
return ret;
}
return 0;
}
static int rdtgroup_seqfile_show(struct seq_file *m, void *arg)
{
struct kernfs_open_file *of = m->private;
struct rftype *rft = of->kn->priv;
if (rft->seq_show)
return rft->seq_show(of, m, arg);
return 0;
}
static ssize_t rdtgroup_file_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, loff_t off)
{
struct rftype *rft = of->kn->priv;
if (rft->write)
return rft->write(of, buf, nbytes, off);
return -EINVAL;
}
static struct kernfs_ops rdtgroup_kf_single_ops = {
.atomic_write_len = PAGE_SIZE,
.write = rdtgroup_file_write,
.seq_show = rdtgroup_seqfile_show,
};
static struct kernfs_ops kf_mondata_ops = {
.atomic_write_len = PAGE_SIZE,
.seq_show = rdtgroup_mondata_show,
};
static bool is_cpu_list(struct kernfs_open_file *of)
{
struct rftype *rft = of->kn->priv;
return rft->flags & RFTYPE_FLAGS_CPUS_LIST;
}
static int rdtgroup_cpus_show(struct kernfs_open_file *of,
struct seq_file *s, void *v)
{
struct rdtgroup *rdtgrp;
int ret = 0;
rdtgrp = rdtgroup_kn_lock_live(of->kn);
if (rdtgrp) {
seq_printf(s, is_cpu_list(of) ? "%*pbl\n" : "%*pb\n",
cpumask_pr_args(&rdtgrp->cpu_mask));
} else {
ret = -ENOENT;
}
rdtgroup_kn_unlock(of->kn);
return ret;
}
/*
* This is safe against intel_rdt_sched_in() called from __switch_to()
* because __switch_to() is executed with interrupts disabled. A local call
* from update_closid_rmid() is proteced against __switch_to() because
* preemption is disabled.
*/
static void update_cpu_closid_rmid(void *info)
{
struct rdtgroup *r = info;
if (r) {
this_cpu_write(pqr_state.default_closid, r->closid);
this_cpu_write(pqr_state.default_rmid, r->mon.rmid);
}
/*
* We cannot unconditionally write the MSR because the current
* executing task might have its own closid selected. Just reuse
* the context switch code.
*/
intel_rdt_sched_in();
}
/*
* Update the PGR_ASSOC MSR on all cpus in @cpu_mask,
*
* Per task closids/rmids must have been set up before calling this function.
*/
static void
update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r)
{
int cpu = get_cpu();
if (cpumask_test_cpu(cpu, cpu_mask))
update_cpu_closid_rmid(r);
smp_call_function_many(cpu_mask, update_cpu_closid_rmid, r, 1);
put_cpu();
}
static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
cpumask_var_t tmpmask)
{
struct rdtgroup *prgrp = rdtgrp->mon.parent, *crgrp;
struct list_head *head;
/* Check whether cpus belong to parent ctrl group */
cpumask_andnot(tmpmask, newmask, &prgrp->cpu_mask);
if (cpumask_weight(tmpmask)) {
rdt_last_cmd_puts("can only add CPUs to mongroup that belong to parent\n");
return -EINVAL;
}
/* Check whether cpus are dropped from this group */
cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
if (cpumask_weight(tmpmask)) {
/* Give any dropped cpus to parent rdtgroup */
cpumask_or(&prgrp->cpu_mask, &prgrp->cpu_mask, tmpmask);
update_closid_rmid(tmpmask, prgrp);
}
/*
* If we added cpus, remove them from previous group that owned them
* and update per-cpu rmid
*/
cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
if (cpumask_weight(tmpmask)) {
head = &prgrp->mon.crdtgrp_list;
list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
if (crgrp == rdtgrp)
continue;
cpumask_andnot(&crgrp->cpu_mask, &crgrp->cpu_mask,
tmpmask);
}
update_closid_rmid(tmpmask, rdtgrp);
}
/* Done pushing/pulling - update this group with new mask */
cpumask_copy(&rdtgrp->cpu_mask, newmask);
return 0;
}
static void cpumask_rdtgrp_clear(struct rdtgroup *r, struct cpumask *m)
{
struct rdtgroup *crgrp;
cpumask_andnot(&r->cpu_mask, &r->cpu_mask, m);
/* update the child mon group masks as well*/
list_for_each_entry(crgrp, &r->mon.crdtgrp_list, mon.crdtgrp_list)
cpumask_and(&crgrp->cpu_mask, &r->cpu_mask, &crgrp->cpu_mask);
}
static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
cpumask_var_t tmpmask, cpumask_var_t tmpmask1)
{
struct rdtgroup *r, *crgrp;
struct list_head *head;
/* Check whether cpus are dropped from this group */
cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
if (cpumask_weight(tmpmask)) {
/* Can't drop from default group */
if (rdtgrp == &rdtgroup_default) {
rdt_last_cmd_puts("Can't drop CPUs from default group\n");
return -EINVAL;
}
/* Give any dropped cpus to rdtgroup_default */
cpumask_or(&rdtgroup_default.cpu_mask,
&rdtgroup_default.cpu_mask, tmpmask);
update_closid_rmid(tmpmask, &rdtgroup_default);
}
/*
* If we added cpus, remove them from previous group and
* the prev group's child groups that owned them
* and update per-cpu closid/rmid.
*/
cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
if (cpumask_weight(tmpmask)) {
list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) {
if (r == rdtgrp)
continue;
cpumask_and(tmpmask1, &r->cpu_mask, tmpmask);
if (cpumask_weight(tmpmask1))
cpumask_rdtgrp_clear(r, tmpmask1);
}
update_closid_rmid(tmpmask, rdtgrp);
}
/* Done pushing/pulling - update this group with new mask */
cpumask_copy(&rdtgrp->cpu_mask, newmask);
/*
* Clear child mon group masks since there is a new parent mask
* now and update the rmid for the cpus the child lost.
*/
head = &rdtgrp->mon.crdtgrp_list;
list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
cpumask_and(tmpmask, &rdtgrp->cpu_mask, &crgrp->cpu_mask);
update_closid_rmid(tmpmask, rdtgrp);
cpumask_clear(&crgrp->cpu_mask);
}
return 0;
}
static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off)
{
cpumask_var_t tmpmask, newmask, tmpmask1;
struct rdtgroup *rdtgrp;
int ret;
if (!buf)
return -EINVAL;
if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
return -ENOMEM;
if (!zalloc_cpumask_var(&newmask, GFP_KERNEL)) {
free_cpumask_var(tmpmask);
return -ENOMEM;
}
if (!zalloc_cpumask_var(&tmpmask1, GFP_KERNEL)) {
free_cpumask_var(tmpmask);
free_cpumask_var(newmask);
return -ENOMEM;
}
rdtgrp = rdtgroup_kn_lock_live(of->kn);
rdt_last_cmd_clear();
if (!rdtgrp) {
ret = -ENOENT;
rdt_last_cmd_puts("directory was removed\n");
goto unlock;
}
if (is_cpu_list(of))
ret = cpulist_parse(buf, newmask);
else
ret = cpumask_parse(buf, newmask);
if (ret) {
rdt_last_cmd_puts("bad cpu list/mask\n");
goto unlock;
}
/* check that user didn't specify any offline cpus */
cpumask_andnot(tmpmask, newmask, cpu_online_mask);
if (cpumask_weight(tmpmask)) {
ret = -EINVAL;
rdt_last_cmd_puts("can only assign online cpus\n");
goto unlock;
}
if (rdtgrp->type == RDTCTRL_GROUP)
ret = cpus_ctrl_write(rdtgrp, newmask, tmpmask, tmpmask1);
else if (rdtgrp->type == RDTMON_GROUP)
ret = cpus_mon_write(rdtgrp, newmask, tmpmask);
else
ret = -EINVAL;
unlock:
rdtgroup_kn_unlock(of->kn);
free_cpumask_var(tmpmask);
free_cpumask_var(newmask);
free_cpumask_var(tmpmask1);
return ret ?: nbytes;
}
struct task_move_callback {
struct callback_head work;
struct rdtgroup *rdtgrp;
};
static void move_myself(struct callback_head *head)
{
struct task_move_callback *callback;
struct rdtgroup *rdtgrp;
callback = container_of(head, struct task_move_callback, work);
rdtgrp = callback->rdtgrp;
/*
* If resource group was deleted before this task work callback
* was invoked, then assign the task to root group and free the
* resource group.
*/
if (atomic_dec_and_test(&rdtgrp->waitcount) &&
(rdtgrp->flags & RDT_DELETED)) {
current->closid = 0;
current->rmid = 0;
kfree(rdtgrp);
}
preempt_disable();
/* update PQR_ASSOC MSR to make resource group go into effect */
intel_rdt_sched_in();
preempt_enable();
kfree(callback);
}
static int __rdtgroup_move_task(struct task_struct *tsk,
struct rdtgroup *rdtgrp)
{
struct task_move_callback *callback;
int ret;
callback = kzalloc(sizeof(*callback), GFP_KERNEL);
if (!callback)
return -ENOMEM;
callback->work.func = move_myself;
callback->rdtgrp = rdtgrp;
/*
* Take a refcount, so rdtgrp cannot be freed before the
* callback has been invoked.
*/
atomic_inc(&rdtgrp->waitcount);
ret = task_work_add(tsk, &callback->work, true);
if (ret) {
/*
* Task is exiting. Drop the refcount and free the callback.
* No need to check the refcount as the group cannot be
* deleted before the write function unlocks rdtgroup_mutex.
*/
atomic_dec(&rdtgrp->waitcount);
kfree(callback);
rdt_last_cmd_puts("task exited\n");
} else {
/*
* For ctrl_mon groups move both closid and rmid.
* For monitor groups, can move the tasks only from
* their parent CTRL group.
*/
if (rdtgrp->type == RDTCTRL_GROUP) {
tsk->closid = rdtgrp->closid;
tsk->rmid = rdtgrp->mon.rmid;
} else if (rdtgrp->type == RDTMON_GROUP) {
if (rdtgrp->mon.parent->closid == tsk->closid) {
tsk->rmid = rdtgrp->mon.rmid;
} else {
rdt_last_cmd_puts("Can't move task to different control group\n");
ret = -EINVAL;
}
}
}
return ret;
}
static int rdtgroup_task_write_permission(struct task_struct *task,
struct kernfs_open_file *of)
{
const struct cred *tcred = get_task_cred(task);
const struct cred *cred = current_cred();
int ret = 0;
/*
* Even if we're attaching all tasks in the thread group, we only
* need to check permissions on one of them.
*/
if (!uid_eq(cred->euid, GLOBAL_ROOT_UID) &&
!uid_eq(cred->euid, tcred->uid) &&
!uid_eq(cred->euid, tcred->suid)) {
rdt_last_cmd_printf("No permission to move task %d\n", task->pid);
ret = -EPERM;
}
put_cred(tcred);
return ret;
}
static int rdtgroup_move_task(pid_t pid, struct rdtgroup *rdtgrp,
struct kernfs_open_file *of)
{
struct task_struct *tsk;
int ret;
rcu_read_lock();
if (pid) {
tsk = find_task_by_vpid(pid);
if (!tsk) {
rcu_read_unlock();
rdt_last_cmd_printf("No task %d\n", pid);
return -ESRCH;
}
} else {
tsk = current;
}
get_task_struct(tsk);
rcu_read_unlock();
ret = rdtgroup_task_write_permission(tsk, of);
if (!ret)
ret = __rdtgroup_move_task(tsk, rdtgrp);
put_task_struct(tsk);
return ret;
}
static ssize_t rdtgroup_tasks_write(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off)
{
struct rdtgroup *rdtgrp;
int ret = 0;
pid_t pid;
if (kstrtoint(strstrip(buf), 0, &pid) || pid < 0)
return -EINVAL;
rdtgrp = rdtgroup_kn_lock_live(of->kn);
rdt_last_cmd_clear();
if (rdtgrp)
ret = rdtgroup_move_task(pid, rdtgrp, of);
else
ret = -ENOENT;
rdtgroup_kn_unlock(of->kn);
return ret ?: nbytes;
}
static void show_rdt_tasks(struct rdtgroup *r, struct seq_file *s)
{
struct task_struct *p, *t;
rcu_read_lock();
for_each_process_thread(p, t) {
if ((r->type == RDTCTRL_GROUP && t->closid == r->closid) ||
(r->type == RDTMON_GROUP && t->rmid == r->mon.rmid))
seq_printf(s, "%d\n", t->pid);
}
rcu_read_unlock();
}
static int rdtgroup_tasks_show(struct kernfs_open_file *of,
struct seq_file *s, void *v)
{
struct rdtgroup *rdtgrp;
int ret = 0;
rdtgrp = rdtgroup_kn_lock_live(of->kn);
if (rdtgrp)
show_rdt_tasks(rdtgrp, s);
else
ret = -ENOENT;
rdtgroup_kn_unlock(of->kn);
return ret;
}
static int rdt_last_cmd_status_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
int len;
mutex_lock(&rdtgroup_mutex);
len = seq_buf_used(&last_cmd_status);
if (len)
seq_printf(seq, "%.*s", len, last_cmd_status_buf);
else
seq_puts(seq, "ok\n");
mutex_unlock(&rdtgroup_mutex);
return 0;
}
static int rdt_num_closids_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%d\n", r->num_closid);
return 0;
}
static int rdt_default_ctrl_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%x\n", r->default_ctrl);
return 0;
}
static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%u\n", r->cache.min_cbm_bits);
return 0;
}
static int rdt_shareable_bits_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%x\n", r->cache.shareable_bits);
return 0;
}
static int rdt_min_bw_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%u\n", r->membw.min_bw);
return 0;
}
static int rdt_num_rmids_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%d\n", r->num_rmid);
return 0;
}
static int rdt_mon_features_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
struct mon_evt *mevt;
list_for_each_entry(mevt, &r->evt_list, list)
seq_printf(seq, "%s\n", mevt->name);
return 0;
}
static int rdt_bw_gran_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%u\n", r->membw.bw_gran);
return 0;
}
static int rdt_delay_linear_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%u\n", r->membw.delay_linear);
return 0;
}
static int max_threshold_occ_show(struct kernfs_open_file *of,
struct seq_file *seq, void *v)
{
struct rdt_resource *r = of->kn->parent->priv;
seq_printf(seq, "%u\n", intel_cqm_threshold * r->mon_scale);
return 0;
}
static ssize_t max_threshold_occ_write(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off)
{
struct rdt_resource *r = of->kn->parent->priv;
unsigned int bytes;
int ret;
ret = kstrtouint(buf, 0, &bytes);
if (ret)
return ret;
if (bytes > (boot_cpu_data.x86_cache_size * 1024))
return -EINVAL;
intel_cqm_threshold = bytes / r->mon_scale;
return nbytes;
}
/* rdtgroup information files for one cache resource. */
static struct rftype res_common_files[] = {
{
.name = "last_cmd_status",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_last_cmd_status_show,
.fflags = RF_TOP_INFO,
},
{
.name = "num_closids",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_num_closids_show,
.fflags = RF_CTRL_INFO,
},
{
.name = "mon_features",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_mon_features_show,
.fflags = RF_MON_INFO,
},
{
.name = "num_rmids",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_num_rmids_show,
.fflags = RF_MON_INFO,
},
{
.name = "cbm_mask",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_default_ctrl_show,
.fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE,
},
{
.name = "min_cbm_bits",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_min_cbm_bits_show,
.fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE,
},
{
.name = "shareable_bits",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_shareable_bits_show,
.fflags = RF_CTRL_INFO | RFTYPE_RES_CACHE,
},
{
.name = "min_bandwidth",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_min_bw_show,
.fflags = RF_CTRL_INFO | RFTYPE_RES_MB,
},
{
.name = "bandwidth_gran",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_bw_gran_show,
.fflags = RF_CTRL_INFO | RFTYPE_RES_MB,
},
{
.name = "delay_linear",
.mode = 0444,
.kf_ops = &rdtgroup_kf_single_ops,
.seq_show = rdt_delay_linear_show,
.fflags = RF_CTRL_INFO | RFTYPE_RES_MB,
},
{
.name = "max_threshold_occupancy",
.mode = 0644,
.kf_ops = &rdtgroup_kf_single_ops,
.write = max_threshold_occ_write,
.seq_show = max_threshold_occ_show,
.fflags = RF_MON_INFO | RFTYPE_RES_CACHE,
},
{
.name = "cpus",
.mode = 0644,
.kf_ops = &rdtgroup_kf_single_ops,
.write = rdtgroup_cpus_write,
.seq_show = rdtgroup_cpus_show,
.fflags = RFTYPE_BASE,
},
{
.name = "cpus_list",
.mode = 0644,
.kf_ops = &rdtgroup_kf_single_ops,
.write = rdtgroup_cpus_write,
.seq_show = rdtgroup_cpus_show,
.flags = RFTYPE_FLAGS_CPUS_LIST,
.fflags = RFTYPE_BASE,
},
{
.name = "tasks",
.mode = 0644,
.kf_ops = &rdtgroup_kf_single_ops,
.write = rdtgroup_tasks_write,
.seq_show = rdtgroup_tasks_show,
.fflags = RFTYPE_BASE,
},
{
.name = "schemata",
.mode = 0644,
.kf_ops = &rdtgroup_kf_single_ops,
.write = rdtgroup_schemata_write,
.seq_show = rdtgroup_schemata_show,
.fflags = RF_CTRL_BASE,
},
};
static int rdtgroup_add_files(struct kernfs_node *kn, unsigned long fflags)
{
struct rftype *rfts, *rft;
int ret, len;
rfts = res_common_files;
len = ARRAY_SIZE(res_common_files);
lockdep_assert_held(&rdtgroup_mutex);
for (rft = rfts; rft < rfts + len; rft++) {
if ((fflags & rft->fflags) == rft->fflags) {
ret = rdtgroup_add_file(kn, rft);
if (ret)
goto error;
}
}
return 0;
error:
pr_warn("Failed to add %s, err=%d\n", rft->name, ret);
while (--rft >= rfts) {
if ((fflags & rft->fflags) == rft->fflags)
kernfs_remove_by_name(kn, rft->name);
}
return ret;
}
static int rdtgroup_mkdir_info_resdir(struct rdt_resource *r, char *name,
unsigned long fflags)
{
struct kernfs_node *kn_subdir;
int ret;
kn_subdir = kernfs_create_dir(kn_info, name,
kn_info->mode, r);
if (IS_ERR(kn_subdir))
return PTR_ERR(kn_subdir);
kernfs_get(kn_subdir);
ret = rdtgroup_kn_set_ugid(kn_subdir);
if (ret)
return ret;
ret = rdtgroup_add_files(kn_subdir, fflags);
if (!ret)
kernfs_activate(kn_subdir);
return ret;
}
static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
{
struct rdt_resource *r;
unsigned long fflags;
char name[32];
int ret;
/* create the directory */
kn_info = kernfs_create_dir(parent_kn, "info", parent_kn->mode, NULL);
if (IS_ERR(kn_info))
return PTR_ERR(kn_info);
kernfs_get(kn_info);
ret = rdtgroup_add_files(kn_info, RF_TOP_INFO);
if (ret)
goto out_destroy;
for_each_alloc_enabled_rdt_resource(r) {
fflags = r->fflags | RF_CTRL_INFO;
ret = rdtgroup_mkdir_info_resdir(r, r->name, fflags);
if (ret)
goto out_destroy;
}
for_each_mon_enabled_rdt_resource(r) {
fflags = r->fflags | RF_MON_INFO;
sprintf(name, "%s_MON", r->name);
ret = rdtgroup_mkdir_info_resdir(r, name, fflags);
if (ret)
goto out_destroy;
}
/*
* This extra ref will be put in kernfs_remove() and guarantees
* that @rdtgrp->kn is always accessible.
*/
kernfs_get(kn_info);
ret = rdtgroup_kn_set_ugid(kn_info);
if (ret)
goto out_destroy;
kernfs_activate(kn_info);
return 0;
out_destroy:
kernfs_remove(kn_info);
return ret;
}
static int
mongroup_create_dir(struct kernfs_node *parent_kn, struct rdtgroup *prgrp,
char *name, struct kernfs_node **dest_kn)
{
struct kernfs_node *kn;
int ret;
/* create the directory */
kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
if (IS_ERR(kn))
return PTR_ERR(kn);
if (dest_kn)
*dest_kn = kn;
/*
* This extra ref will be put in kernfs_remove() and guarantees
* that @rdtgrp->kn is always accessible.
*/
kernfs_get(kn);
ret = rdtgroup_kn_set_ugid(kn);
if (ret)
goto out_destroy;
kernfs_activate(kn);
return 0;
out_destroy:
kernfs_remove(kn);
return ret;
}
static void l3_qos_cfg_update(void *arg)
{
bool *enable = arg;
wrmsrl(IA32_L3_QOS_CFG, *enable ? L3_QOS_CDP_ENABLE : 0ULL);
}
static void l2_qos_cfg_update(void *arg)
{
bool *enable = arg;
wrmsrl(IA32_L2_QOS_CFG, *enable ? L2_QOS_CDP_ENABLE : 0ULL);
}
static int set_cache_qos_cfg(int level, bool enable)
{
void (*update)(void *arg);
struct rdt_resource *r_l;
cpumask_var_t cpu_mask;
struct rdt_domain *d;
int cpu;
if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
return -ENOMEM;
if (level == RDT_RESOURCE_L3)
update = l3_qos_cfg_update;
else if (level == RDT_RESOURCE_L2)
update = l2_qos_cfg_update;
else
return -EINVAL;
r_l = &rdt_resources_all[level];
list_for_each_entry(d, &r_l->domains, list) {
/* Pick one CPU from each domain instance to update MSR */
cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
}
cpu = get_cpu();
/* Update QOS_CFG MSR on this cpu if it's in cpu_mask. */
if (cpumask_test_cpu(cpu, cpu_mask))
update(&enable);
/* Update QOS_CFG MSR on all other cpus in cpu_mask. */
smp_call_function_many(cpu_mask, update, &enable, 1);
put_cpu();
free_cpumask_var(cpu_mask);
return 0;
}
static int cdp_enable(int level, int data_type, int code_type)
{
struct rdt_resource *r_ldata = &rdt_resources_all[data_type];
struct rdt_resource *r_lcode = &rdt_resources_all[code_type];
struct rdt_resource *r_l = &rdt_resources_all[level];
int ret;
if (!r_l->alloc_capable || !r_ldata->alloc_capable ||
!r_lcode->alloc_capable)
return -EINVAL;
ret = set_cache_qos_cfg(level, true);
if (!ret) {
r_l->alloc_enabled = false;
r_ldata->alloc_enabled = true;
r_lcode->alloc_enabled = true;
}
return ret;
}
static int cdpl3_enable(void)
{
return cdp_enable(RDT_RESOURCE_L3, RDT_RESOURCE_L3DATA,
RDT_RESOURCE_L3CODE);
}
static int cdpl2_enable(void)
{
return cdp_enable(RDT_RESOURCE_L2, RDT_RESOURCE_L2DATA,
RDT_RESOURCE_L2CODE);
}
static void cdp_disable(int level, int data_type, int code_type)
{
struct rdt_resource *r = &rdt_resources_all[level];
r->alloc_enabled = r->alloc_capable;
if (rdt_resources_all[data_type].alloc_enabled) {
rdt_resources_all[data_type].alloc_enabled = false;
rdt_resources_all[code_type].alloc_enabled = false;
set_cache_qos_cfg(level, false);
}
}
static void cdpl3_disable(void)
{
cdp_disable(RDT_RESOURCE_L3, RDT_RESOURCE_L3DATA, RDT_RESOURCE_L3CODE);
}
static void cdpl2_disable(void)
{
cdp_disable(RDT_RESOURCE_L2, RDT_RESOURCE_L2DATA, RDT_RESOURCE_L2CODE);
}
static void cdp_disable_all(void)
{
if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled)
cdpl3_disable();
if (rdt_resources_all[RDT_RESOURCE_L2DATA].alloc_enabled)
cdpl2_disable();
}
static int parse_rdtgroupfs_options(char *data)
{
char *token, *o = data;
int ret = 0;
while ((token = strsep(&o, ",")) != NULL) {
if (!*token) {
ret = -EINVAL;
goto out;
}
if (!strcmp(token, "cdp")) {
ret = cdpl3_enable();
if (ret)
goto out;
} else if (!strcmp(token, "cdpl2")) {
ret = cdpl2_enable();
if (ret)
goto out;
} else {
ret = -EINVAL;
goto out;
}
}
return 0;
out:
pr_err("Invalid mount option \"%s\"\n", token);
return ret;
}
/*
* We don't allow rdtgroup directories to be created anywhere
* except the root directory. Thus when looking for the rdtgroup
* structure for a kernfs node we are either looking at a directory,
* in which case the rdtgroup structure is pointed at by the "priv"
* field, otherwise we have a file, and need only look to the parent
* to find the rdtgroup.
*/
static struct rdtgroup *kernfs_to_rdtgroup(struct kernfs_node *kn)
{
if (kernfs_type(kn) == KERNFS_DIR) {
/*
* All the resource directories use "kn->priv"
* to point to the "struct rdtgroup" for the
* resource. "info" and its subdirectories don't
* have rdtgroup structures, so return NULL here.
*/
if (kn == kn_info || kn->parent == kn_info)
return NULL;
else
return kn->priv;
} else {
return kn->parent->priv;
}
}
struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn)
{
struct rdtgroup *rdtgrp = kernfs_to_rdtgroup(kn);
if (!rdtgrp)
return NULL;
atomic_inc(&rdtgrp->waitcount);
kernfs_break_active_protection(kn);
mutex_lock(&rdtgroup_mutex);
/* Was this group deleted while we waited? */
if (rdtgrp->flags & RDT_DELETED)
return NULL;
return rdtgrp;
}
void rdtgroup_kn_unlock(struct kernfs_node *kn)
{
struct rdtgroup *rdtgrp = kernfs_to_rdtgroup(kn);
if (!rdtgrp)
return;
mutex_unlock(&rdtgroup_mutex);
if (atomic_dec_and_test(&rdtgrp->waitcount) &&
(rdtgrp->flags & RDT_DELETED)) {
kernfs_unbreak_active_protection(kn);
kernfs_put(rdtgrp->kn);
kfree(rdtgrp);
} else {
kernfs_unbreak_active_protection(kn);
}
}
static int mkdir_mondata_all(struct kernfs_node *parent_kn,
struct rdtgroup *prgrp,
struct kernfs_node **mon_data_kn);
static struct dentry *rdt_mount(struct file_system_type *fs_type,
int flags, const char *unused_dev_name,
void *data)
{
struct rdt_domain *dom;
struct rdt_resource *r;
struct dentry *dentry;
int ret;
cpus_read_lock();
mutex_lock(&rdtgroup_mutex);
/*
* resctrl file system can only be mounted once.
*/
if (static_branch_unlikely(&rdt_enable_key)) {
dentry = ERR_PTR(-EBUSY);
goto out;
}
ret = parse_rdtgroupfs_options(data);
if (ret) {
dentry = ERR_PTR(ret);
goto out_cdp;
}
closid_init();
ret = rdtgroup_create_info_dir(rdtgroup_default.kn);
if (ret) {
dentry = ERR_PTR(ret);
goto out_cdp;
}
if (rdt_mon_capable) {
ret = mongroup_create_dir(rdtgroup_default.kn,
NULL, "mon_groups",
&kn_mongrp);
if (ret) {
dentry = ERR_PTR(ret);
goto out_info;
}
kernfs_get(kn_mongrp);
ret = mkdir_mondata_all(rdtgroup_default.kn,
&rdtgroup_default, &kn_mondata);
if (ret) {
dentry = ERR_PTR(ret);
goto out_mongrp;
}
kernfs_get(kn_mondata);
rdtgroup_default.mon.mon_data_kn = kn_mondata;
}
dentry = kernfs_mount(fs_type, flags, rdt_root,
RDTGROUP_SUPER_MAGIC, NULL);
if (IS_ERR(dentry))
goto out_mondata;
if (rdt_alloc_capable)
static_branch_enable_cpuslocked(&rdt_alloc_enable_key);
if (rdt_mon_capable)
static_branch_enable_cpuslocked(&rdt_mon_enable_key);
if (rdt_alloc_capable || rdt_mon_capable)
static_branch_enable_cpuslocked(&rdt_enable_key);
if (is_mbm_enabled()) {
r = &rdt_resources_all[RDT_RESOURCE_L3];
list_for_each_entry(dom, &r->domains, list)
mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL);
}
goto out;
out_mondata:
if (rdt_mon_capable)
kernfs_remove(kn_mondata);
out_mongrp:
if (rdt_mon_capable)
kernfs_remove(kn_mongrp);
out_info:
kernfs_remove(kn_info);
out_cdp:
cdp_disable_all();
out:
rdt_last_cmd_clear();
mutex_unlock(&rdtgroup_mutex);
cpus_read_unlock();
return dentry;
}
static int reset_all_ctrls(struct rdt_resource *r)
{
struct msr_param msr_param;
cpumask_var_t cpu_mask;
struct rdt_domain *d;
int i, cpu;
if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
return -ENOMEM;
msr_param.res = r;
msr_param.low = 0;
msr_param.high = r->num_closid;
/*
* Disable resource control for this resource by setting all
* CBMs in all domains to the maximum mask value. Pick one CPU
* from each domain to update the MSRs below.
*/
list_for_each_entry(d, &r->domains, list) {
cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
for (i = 0; i < r->num_closid; i++)
d->ctrl_val[i] = r->default_ctrl;
}
cpu = get_cpu();
/* Update CBM on this cpu if it's in cpu_mask. */
if (cpumask_test_cpu(cpu, cpu_mask))
rdt_ctrl_update(&msr_param);
/* Update CBM on all other cpus in cpu_mask. */
smp_call_function_many(cpu_mask, rdt_ctrl_update, &msr_param, 1);
put_cpu();
free_cpumask_var(cpu_mask);
return 0;
}
static bool is_closid_match(struct task_struct *t, struct rdtgroup *r)
{
return (rdt_alloc_capable &&
(r->type == RDTCTRL_GROUP) && (t->closid == r->closid));
}
static bool is_rmid_match(struct task_struct *t, struct rdtgroup *r)
{
return (rdt_mon_capable &&
(r->type == RDTMON_GROUP) && (t->rmid == r->mon.rmid));
}
/*
* Move tasks from one to the other group. If @from is NULL, then all tasks
* in the systems are moved unconditionally (used for teardown).
*
* If @mask is not NULL the cpus on which moved tasks are running are set
* in that mask so the update smp function call is restricted to affected
* cpus.
*/
static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
struct cpumask *mask)
{
struct task_struct *p, *t;
read_lock(&tasklist_lock);
for_each_process_thread(p, t) {
if (!from || is_closid_match(t, from) ||
is_rmid_match(t, from)) {
t->closid = to->closid;
t->rmid = to->mon.rmid;
#ifdef CONFIG_SMP
/*
* This is safe on x86 w/o barriers as the ordering
* of writing to task_cpu() and t->on_cpu is
* reverse to the reading here. The detection is
* inaccurate as tasks might move or schedule
* before the smp function call takes place. In
* such a case the function call is pointless, but
* there is no other side effect.
*/
if (mask && t->on_cpu)
cpumask_set_cpu(task_cpu(t), mask);
#endif
}
}
read_unlock(&tasklist_lock);
}
static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
{
struct rdtgroup *sentry, *stmp;
struct list_head *head;
head = &rdtgrp->mon.crdtgrp_list;
list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) {
free_rmid(sentry->mon.rmid);
list_del(&sentry->mon.crdtgrp_list);
kfree(sentry);
}
}
/*
* Forcibly remove all of subdirectories under root.
*/
static void rmdir_all_sub(void)
{
struct rdtgroup *rdtgrp, *tmp;
/* Move all tasks to the default resource group */
rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
/* Free any child rmids */
free_all_child_rdtgrp(rdtgrp);
/* Remove each rdtgroup other than root */
if (rdtgrp == &rdtgroup_default)
continue;
/*
* Give any CPUs back to the default group. We cannot copy
* cpu_online_mask because a CPU might have executed the
* offline callback already, but is still marked online.
*/
cpumask_or(&rdtgroup_default.cpu_mask,
&rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
free_rmid(rdtgrp->mon.rmid);
kernfs_remove(rdtgrp->kn);
list_del(&rdtgrp->rdtgroup_list);
kfree(rdtgrp);
}
/* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */
update_closid_rmid(cpu_online_mask, &rdtgroup_default);
kernfs_remove(kn_info);
kernfs_remove(kn_mongrp);
kernfs_remove(kn_mondata);
}
static void rdt_kill_sb(struct super_block *sb)
{
struct rdt_resource *r;
cpus_read_lock();
mutex_lock(&rdtgroup_mutex);
/*Put everything back to default values. */
for_each_alloc_enabled_rdt_resource(r)
reset_all_ctrls(r);
cdp_disable_all();
rmdir_all_sub();
static_branch_disable_cpuslocked(&rdt_alloc_enable_key);
static_branch_disable_cpuslocked(&rdt_mon_enable_key);
static_branch_disable_cpuslocked(&rdt_enable_key);
kernfs_kill_sb(sb);
mutex_unlock(&rdtgroup_mutex);
cpus_read_unlock();
}
static struct file_system_type rdt_fs_type = {
.name = "resctrl",
.mount = rdt_mount,
.kill_sb = rdt_kill_sb,
};
static int mon_addfile(struct kernfs_node *parent_kn, const char *name,
void *priv)
{
struct kernfs_node *kn;
int ret = 0;
kn = __kernfs_create_file(parent_kn, name, 0444, 0,
&kf_mondata_ops, priv, NULL, NULL);
if (IS_ERR(kn))
return PTR_ERR(kn);
ret = rdtgroup_kn_set_ugid(kn);
if (ret) {
kernfs_remove(kn);
return ret;
}
return ret;
}
/*
* Remove all subdirectories of mon_data of ctrl_mon groups
* and monitor groups with given domain id.
*/
void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r, unsigned int dom_id)
{
struct rdtgroup *prgrp, *crgrp;
char name[32];
if (!r->mon_enabled)
return;
list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
sprintf(name, "mon_%s_%02d", r->name, dom_id);
kernfs_remove_by_name(prgrp->mon.mon_data_kn, name);
list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list)
kernfs_remove_by_name(crgrp->mon.mon_data_kn, name);
}
}
static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
struct rdt_domain *d,
struct rdt_resource *r, struct rdtgroup *prgrp)
{
union mon_data_bits priv;
struct kernfs_node *kn;
struct mon_evt *mevt;
struct rmid_read rr;
char name[32];
int ret;
sprintf(name, "mon_%s_%02d", r->name, d->id);
/* create the directory */
kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
if (IS_ERR(kn))
return PTR_ERR(kn);
/*
* This extra ref will be put in kernfs_remove() and guarantees
* that kn is always accessible.
*/
kernfs_get(kn);
ret = rdtgroup_kn_set_ugid(kn);
if (ret)
goto out_destroy;
if (WARN_ON(list_empty(&r->evt_list))) {
ret = -EPERM;
goto out_destroy;
}
priv.u.rid = r->rid;
priv.u.domid = d->id;
list_for_each_entry(mevt, &r->evt_list, list) {
priv.u.evtid = mevt->evtid;
ret = mon_addfile(kn, mevt->name, priv.priv);
if (ret)
goto out_destroy;
if (is_mbm_event(mevt->evtid))
mon_event_read(&rr, d, prgrp, mevt->evtid, true);
}
kernfs_activate(kn);
return 0;
out_destroy:
kernfs_remove(kn);
return ret;
}
/*
* Add all subdirectories of mon_data for "ctrl_mon" groups
* and "monitor" groups with given domain id.
*/
void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
struct rdt_domain *d)
{
struct kernfs_node *parent_kn;
struct rdtgroup *prgrp, *crgrp;
struct list_head *head;
if (!r->mon_enabled)
return;
list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
parent_kn = prgrp->mon.mon_data_kn;
mkdir_mondata_subdir(parent_kn, d, r, prgrp);
head = &prgrp->mon.crdtgrp_list;
list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
parent_kn = crgrp->mon.mon_data_kn;
mkdir_mondata_subdir(parent_kn, d, r, crgrp);
}
}
}
static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn,
struct rdt_resource *r,
struct rdtgroup *prgrp)
{
struct rdt_domain *dom;
int ret;
list_for_each_entry(dom, &r->domains, list) {
ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp);
if (ret)
return ret;
}
return 0;
}
/*
* This creates a directory mon_data which contains the monitored data.
*
* mon_data has one directory for each domain whic are named
* in the format mon_<domain_name>_<domain_id>. For ex: A mon_data
* with L3 domain looks as below:
* ./mon_data:
* mon_L3_00
* mon_L3_01
* mon_L3_02
* ...
*
* Each domain directory has one file per event:
* ./mon_L3_00/:
* llc_occupancy
*
*/
static int mkdir_mondata_all(struct kernfs_node *parent_kn,
struct rdtgroup *prgrp,
struct kernfs_node **dest_kn)
{
struct rdt_resource *r;
struct kernfs_node *kn;
int ret;
/*
* Create the mon_data directory first.
*/
ret = mongroup_create_dir(parent_kn, NULL, "mon_data", &kn);
if (ret)
return ret;
if (dest_kn)
*dest_kn = kn;
/*
* Create the subdirectories for each domain. Note that all events
* in a domain like L3 are grouped into a resource whose domain is L3
*/
for_each_mon_enabled_rdt_resource(r) {
ret = mkdir_mondata_subdir_alldom(kn, r, prgrp);
if (ret)
goto out_destroy;
}
return 0;
out_destroy:
kernfs_remove(kn);
return ret;
}
static int mkdir_rdt_prepare(struct kernfs_node *parent_kn,
struct kernfs_node *prgrp_kn,
const char *name, umode_t mode,
enum rdt_group_type rtype, struct rdtgroup **r)
{
struct rdtgroup *prdtgrp, *rdtgrp;
struct kernfs_node *kn;
uint files = 0;
int ret;
prdtgrp = rdtgroup_kn_lock_live(prgrp_kn);
rdt_last_cmd_clear();
if (!prdtgrp) {
ret = -ENODEV;
rdt_last_cmd_puts("directory was removed\n");
goto out_unlock;
}
/* allocate the rdtgroup. */
rdtgrp = kzalloc(sizeof(*rdtgrp), GFP_KERNEL);
if (!rdtgrp) {
ret = -ENOSPC;
rdt_last_cmd_puts("kernel out of memory\n");
goto out_unlock;
}
*r = rdtgrp;
rdtgrp->mon.parent = prdtgrp;
rdtgrp->type = rtype;
INIT_LIST_HEAD(&rdtgrp->mon.crdtgrp_list);
/* kernfs creates the directory for rdtgrp */
kn = kernfs_create_dir(parent_kn, name, mode, rdtgrp);
if (IS_ERR(kn)) {
ret = PTR_ERR(kn);
rdt_last_cmd_puts("kernfs create error\n");
goto out_free_rgrp;
}
rdtgrp->kn = kn;
/*
* kernfs_remove() will drop the reference count on "kn" which
* will free it. But we still need it to stick around for the
* rdtgroup_kn_unlock(kn} call below. Take one extra reference
* here, which will be dropped inside rdtgroup_kn_unlock().
*/
kernfs_get(kn);
ret = rdtgroup_kn_set_ugid(kn);
if (ret) {
rdt_last_cmd_puts("kernfs perm error\n");
goto out_destroy;
}
files = RFTYPE_BASE | BIT(RF_CTRLSHIFT + rtype);
ret = rdtgroup_add_files(kn, files);
if (ret) {
rdt_last_cmd_puts("kernfs fill error\n");
goto out_destroy;
}
if (rdt_mon_capable) {
ret = alloc_rmid();
if (ret < 0) {
rdt_last_cmd_puts("out of RMIDs\n");
goto out_destroy;
}
rdtgrp->mon.rmid = ret;
ret = mkdir_mondata_all(kn, rdtgrp, &rdtgrp->mon.mon_data_kn);
if (ret) {
rdt_last_cmd_puts("kernfs subdir error\n");
goto out_idfree;
}
}
kernfs_activate(kn);
/*
* The caller unlocks the prgrp_kn upon success.
*/
return 0;
out_idfree:
free_rmid(rdtgrp->mon.rmid);
out_destroy:
kernfs_remove(rdtgrp->kn);
out_free_rgrp:
kfree(rdtgrp);
out_unlock:
rdtgroup_kn_unlock(prgrp_kn);
return ret;
}
static void mkdir_rdt_prepare_clean(struct rdtgroup *rgrp)
{
kernfs_remove(rgrp->kn);
free_rmid(rgrp->mon.rmid);
kfree(rgrp);
}
/*
* Create a monitor group under "mon_groups" directory of a control
* and monitor group(ctrl_mon). This is a resource group
* to monitor a subset of tasks and cpus in its parent ctrl_mon group.
*/
static int rdtgroup_mkdir_mon(struct kernfs_node *parent_kn,
struct kernfs_node *prgrp_kn,
const char *name,
umode_t mode)
{
struct rdtgroup *rdtgrp, *prgrp;
int ret;
ret = mkdir_rdt_prepare(parent_kn, prgrp_kn, name, mode, RDTMON_GROUP,
&rdtgrp);
if (ret)
return ret;
prgrp = rdtgrp->mon.parent;
rdtgrp->closid = prgrp->closid;
/*
* Add the rdtgrp to the list of rdtgrps the parent
* ctrl_mon group has to track.
*/
list_add_tail(&rdtgrp->mon.crdtgrp_list, &prgrp->mon.crdtgrp_list);
rdtgroup_kn_unlock(prgrp_kn);
return ret;
}
/*
* These are rdtgroups created under the root directory. Can be used
* to allocate and monitor resources.
*/
static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
struct kernfs_node *prgrp_kn,
const char *name, umode_t mode)
{
struct rdtgroup *rdtgrp;
struct kernfs_node *kn;
u32 closid;
int ret;
ret = mkdir_rdt_prepare(parent_kn, prgrp_kn, name, mode, RDTCTRL_GROUP,
&rdtgrp);
if (ret)
return ret;
kn = rdtgrp->kn;
ret = closid_alloc();
if (ret < 0) {
rdt_last_cmd_puts("out of CLOSIDs\n");
goto out_common_fail;
}
closid = ret;
rdtgrp->closid = closid;
list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
if (rdt_mon_capable) {
/*
* Create an empty mon_groups directory to hold the subset
* of tasks and cpus to monitor.
*/
ret = mongroup_create_dir(kn, NULL, "mon_groups", NULL);
if (ret) {
rdt_last_cmd_puts("kernfs subdir error\n");
goto out_id_free;
}
}
goto out_unlock;
out_id_free:
closid_free(closid);
list_del(&rdtgrp->rdtgroup_list);
out_common_fail:
mkdir_rdt_prepare_clean(rdtgrp);
out_unlock:
rdtgroup_kn_unlock(prgrp_kn);
return ret;
}
/*
* We allow creating mon groups only with in a directory called "mon_groups"
* which is present in every ctrl_mon group. Check if this is a valid
* "mon_groups" directory.
*
* 1. The directory should be named "mon_groups".
* 2. The mon group itself should "not" be named "mon_groups".
* This makes sure "mon_groups" directory always has a ctrl_mon group
* as parent.
*/
static bool is_mon_groups(struct kernfs_node *kn, const char *name)
{
return (!strcmp(kn->name, "mon_groups") &&
strcmp(name, "mon_groups"));
}
static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
umode_t mode)
{
/* Do not accept '\n' to avoid unparsable situation. */
if (strchr(name, '\n'))
return -EINVAL;
/*
* If the parent directory is the root directory and RDT
* allocation is supported, add a control and monitoring
* subdirectory
*/
if (rdt_alloc_capable && parent_kn == rdtgroup_default.kn)
return rdtgroup_mkdir_ctrl_mon(parent_kn, parent_kn, name, mode);
/*
* If RDT monitoring is supported and the parent directory is a valid
* "mon_groups" directory, add a monitoring subdirectory.
*/
if (rdt_mon_capable && is_mon_groups(parent_kn, name))
return rdtgroup_mkdir_mon(parent_kn, parent_kn->parent, name, mode);
return -EPERM;
}
static int rdtgroup_rmdir_mon(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
cpumask_var_t tmpmask)
{
struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
int cpu;
/* Give any tasks back to the parent group */
rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
/* Update per cpu rmid of the moved CPUs first */
for_each_cpu(cpu, &rdtgrp->cpu_mask)
per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid;
/*
* Update the MSR on moved CPUs and CPUs which have moved
* task running on them.
*/
cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
update_closid_rmid(tmpmask, NULL);
rdtgrp->flags = RDT_DELETED;
free_rmid(rdtgrp->mon.rmid);
/*
* Remove the rdtgrp from the parent ctrl_mon group's list
*/
WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
list_del(&rdtgrp->mon.crdtgrp_list);
/*
* one extra hold on this, will drop when we kfree(rdtgrp)
* in rdtgroup_kn_unlock()
*/
kernfs_get(kn);
kernfs_remove(rdtgrp->kn);
return 0;
}
static int rdtgroup_rmdir_ctrl(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
cpumask_var_t tmpmask)
{
int cpu;
/* Give any tasks back to the default group */
rdt_move_group_tasks(rdtgrp, &rdtgroup_default, tmpmask);
/* Give any CPUs back to the default group */
cpumask_or(&rdtgroup_default.cpu_mask,
&rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
/* Update per cpu closid and rmid of the moved CPUs first */
for_each_cpu(cpu, &rdtgrp->cpu_mask) {
per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid;
per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid;
}
/*
* Update the MSR on moved CPUs and CPUs which have moved
* task running on them.
*/
cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
update_closid_rmid(tmpmask, NULL);
rdtgrp->flags = RDT_DELETED;
closid_free(rdtgrp->closid);
free_rmid(rdtgrp->mon.rmid);
/*
* Free all the child monitor group rmids.
*/
free_all_child_rdtgrp(rdtgrp);
list_del(&rdtgrp->rdtgroup_list);
/*
* one extra hold on this, will drop when we kfree(rdtgrp)
* in rdtgroup_kn_unlock()
*/
kernfs_get(kn);
kernfs_remove(rdtgrp->kn);
return 0;
}
static int rdtgroup_rmdir(struct kernfs_node *kn)
{
struct kernfs_node *parent_kn = kn->parent;
struct rdtgroup *rdtgrp;
cpumask_var_t tmpmask;
int ret = 0;
if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
return -ENOMEM;
rdtgrp = rdtgroup_kn_lock_live(kn);
if (!rdtgrp) {
ret = -EPERM;
goto out;
}
/*
* If the rdtgroup is a ctrl_mon group and parent directory
* is the root directory, remove the ctrl_mon group.
*
* If the rdtgroup is a mon group and parent directory
* is a valid "mon_groups" directory, remove the mon group.
*/
if (rdtgrp->type == RDTCTRL_GROUP && parent_kn == rdtgroup_default.kn)
ret = rdtgroup_rmdir_ctrl(kn, rdtgrp, tmpmask);
else if (rdtgrp->type == RDTMON_GROUP &&
is_mon_groups(parent_kn, kn->name))
ret = rdtgroup_rmdir_mon(kn, rdtgrp, tmpmask);
else
ret = -EPERM;
out:
rdtgroup_kn_unlock(kn);
free_cpumask_var(tmpmask);
return ret;
}
static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
{
if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled)
seq_puts(seq, ",cdp");
return 0;
}
static struct kernfs_syscall_ops rdtgroup_kf_syscall_ops = {
.mkdir = rdtgroup_mkdir,
.rmdir = rdtgroup_rmdir,
.show_options = rdtgroup_show_options,
};
static int __init rdtgroup_setup_root(void)
{
int ret;
rdt_root = kernfs_create_root(&rdtgroup_kf_syscall_ops,
KERNFS_ROOT_CREATE_DEACTIVATED,
&rdtgroup_default);
if (IS_ERR(rdt_root))
return PTR_ERR(rdt_root);
mutex_lock(&rdtgroup_mutex);
rdtgroup_default.closid = 0;
rdtgroup_default.mon.rmid = 0;
rdtgroup_default.type = RDTCTRL_GROUP;
INIT_LIST_HEAD(&rdtgroup_default.mon.crdtgrp_list);
list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups);
ret = rdtgroup_add_files(rdt_root->kn, RF_CTRL_BASE);
if (ret) {
kernfs_destroy_root(rdt_root);
goto out;
}
rdtgroup_default.kn = rdt_root->kn;
kernfs_activate(rdtgroup_default.kn);
out:
mutex_unlock(&rdtgroup_mutex);
return ret;
}
/*
* rdtgroup_init - rdtgroup initialization
*
* Setup resctrl file system including set up root, create mount point,
* register rdtgroup filesystem, and initialize files under root directory.
*
* Return: 0 on success or -errno
*/
int __init rdtgroup_init(void)
{
int ret = 0;
seq_buf_init(&last_cmd_status, last_cmd_status_buf,
sizeof(last_cmd_status_buf));
ret = rdtgroup_setup_root();
if (ret)
return ret;
ret = sysfs_create_mount_point(fs_kobj, "resctrl");
if (ret)
goto cleanup_root;
ret = register_filesystem(&rdt_fs_type);
if (ret)
goto cleanup_mountpoint;
return 0;
cleanup_mountpoint:
sysfs_remove_mount_point(fs_kobj, "resctrl");
cleanup_root:
kernfs_destroy_root(rdt_root);
return ret;
}
|