arch/x86/oprofile/op_model_amd.c

   1 /*
   2  * @file op_model_amd.c
   3  * athlon / K7 / K8 / Family 10h model-specific MSR operations
   4  *
   5  * @remark Copyright 2002-2009 OProfile authors
   6  * @remark Read the file COPYING
   7  *
   8  * @author John Levon
   9  * @author Philippe Elie
  10  * @author Graydon Hoare
  11  * @author Robert Richter <robert.richter@amd.com>
  12  * @author Barry Kasindorf <barry.kasindorf@amd.com>
  13  * @author Jason Yeh <jason.yeh@amd.com>
  14  * @author Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
  15  */
  16
  17 #include <linux/oprofile.h>
  18 #include <linux/device.h>
  19 #include <linux/pci.h>
  20 #include <linux/percpu.h>
  21
  22 #include <asm/ptrace.h>
  23 #include <asm/msr.h>
  24 #include <asm/nmi.h>
  25 #include <asm/apic.h>
  26 #include <asm/processor.h>
  27 #include <asm/cpufeature.h>
  28
  29 #include "op_x86_model.h"
  30 #include "op_counter.h"
  31
  32 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
  33 #define NUM_VIRT_COUNTERS       32
  34 #else
  35 #define NUM_VIRT_COUNTERS       0
  36 #endif
  37
  38 #define OP_EVENT_MASK                   0x0FFF
  39 #define OP_CTR_OVERFLOW                 (1ULL<<31)
  40
  41 #define MSR_AMD_EVENTSEL_RESERVED       ((0xFFFFFCF0ULL<<32)|(1ULL<<21))
  42
  43 static int num_counters;
  44 static unsigned long reset_value[OP_MAX_COUNTER];
  45
  46 #define IBS_FETCH_SIZE                  6
  47 #define IBS_OP_SIZE                     12
  48
  49 static u32 ibs_caps;
  50
  51 struct ibs_config {
  52         unsigned long op_enabled;
  53         unsigned long fetch_enabled;
  54         unsigned long max_cnt_fetch;
  55         unsigned long max_cnt_op;
  56         unsigned long rand_en;
  57         unsigned long dispatched_ops;
  58         unsigned long branch_target;
  59 };
  60
  61 struct ibs_state {
  62         u64             ibs_op_ctl;
  63         int             branch_target;
  64         unsigned long   sample_size;
  65 };
  66
  67 static struct ibs_config ibs_config;
  68 static struct ibs_state ibs_state;
  69
  70 /*
  71  * IBS randomization macros
  72  */
  73 #define IBS_RANDOM_BITS                 12
  74 #define IBS_RANDOM_MASK                 ((1ULL << IBS_RANDOM_BITS) - 1)
  75 #define IBS_RANDOM_MAXCNT_OFFSET        (1ULL << (IBS_RANDOM_BITS - 5))
  76
  77 /*
  78  * 16-bit Linear Feedback Shift Register (LFSR)
  79  *
  80  *                       16   14   13    11
  81  * Feedback polynomial = X  + X  + X  +  X  + 1
  82  */
  83 static unsigned int lfsr_random(void)
  84 {
  85         static unsigned int lfsr_value = 0xF00D;
  86         unsigned int bit;
  87
  88         /* Compute next bit to shift in */
  89         bit = ((lfsr_value >> 0) ^
  90                (lfsr_value >> 2) ^
  91                (lfsr_value >> 3) ^
  92                (lfsr_value >> 5)) & 0x0001;
  93
  94         /* Advance to next register value */
  95         lfsr_value = (lfsr_value >> 1) | (bit << 15);
  96
  97         return lfsr_value;
  98 }
  99
 100 /*
 101  * IBS software randomization
 102  *
 103  * The IBS periodic op counter is randomized in software. The lower 12
 104  * bits of the 20 bit counter are randomized. IbsOpCurCnt is
 105  * initialized with a 12 bit random value.
 106  */
 107 static inline u64 op_amd_randomize_ibs_op(u64 val)
 108 {
 109         unsigned int random = lfsr_random();
 110
 111         if (!(ibs_caps & IBS_CAPS_RDWROPCNT))
 112                 /*
 113                  * Work around if the hw can not write to IbsOpCurCnt
 114                  *
 115                  * Randomize the lower 8 bits of the 16 bit
 116                  * IbsOpMaxCnt [15:0] value in the range of -128 to
 117                  * +127 by adding/subtracting an offset to the
 118                  * maximum count (IbsOpMaxCnt).
 119                  *
 120                  * To avoid over or underflows and protect upper bits
 121                  * starting at bit 16, the initial value for
 122                  * IbsOpMaxCnt must fit in the range from 0x0081 to
 123                  * 0xff80.
 124                  */
 125                 val += (s8)(random >> 4);
 126         else
 127                 val |= (u64)(random & IBS_RANDOM_MASK) << 32;
 128
 129         return val;
 130 }
 131
 132 static inline void
 133 op_amd_handle_ibs(struct pt_regs * const regs,
 134                   struct op_msrs const * const msrs)
 135 {
 136         u64 val, ctl;
 137         struct op_entry entry;
 138
 139         if (!ibs_caps)
 140                 return;
 141
 142         if (ibs_config.fetch_enabled) {
 143                 rdmsrl(MSR_AMD64_IBSFETCHCTL, ctl);
 144                 if (ctl & IBS_FETCH_VAL) {
 145                         rdmsrl(MSR_AMD64_IBSFETCHLINAD, val);
 146                         oprofile_write_reserve(&entry, regs, val,
 147                                                IBS_FETCH_CODE, IBS_FETCH_SIZE);
 148                         oprofile_add_data64(&entry, val);
 149                         oprofile_add_data64(&entry, ctl);
 150                         rdmsrl(MSR_AMD64_IBSFETCHPHYSAD, val);
 151                         oprofile_add_data64(&entry, val);
 152                         oprofile_write_commit(&entry);
 153
 154                         /* reenable the IRQ */
 155                         ctl &= ~(IBS_FETCH_VAL | IBS_FETCH_CNT);
 156                         ctl |= IBS_FETCH_ENABLE;
 157                         wrmsrl(MSR_AMD64_IBSFETCHCTL, ctl);
 158                 }
 159         }
 160
 161         if (ibs_config.op_enabled) {
 162                 rdmsrl(MSR_AMD64_IBSOPCTL, ctl);
 163                 if (ctl & IBS_OP_VAL) {
 164                         rdmsrl(MSR_AMD64_IBSOPRIP, val);
 165                         oprofile_write_reserve(&entry, regs, val, IBS_OP_CODE,
 166                                                ibs_state.sample_size);
 167                         oprofile_add_data64(&entry, val);
 168                         rdmsrl(MSR_AMD64_IBSOPDATA, val);
 169                         oprofile_add_data64(&entry, val);
 170                         rdmsrl(MSR_AMD64_IBSOPDATA2, val);
 171                         oprofile_add_data64(&entry, val);
 172                         rdmsrl(MSR_AMD64_IBSOPDATA3, val);
 173                         oprofile_add_data64(&entry, val);
 174                         rdmsrl(MSR_AMD64_IBSDCLINAD, val);
 175                         oprofile_add_data64(&entry, val);
 176                         rdmsrl(MSR_AMD64_IBSDCPHYSAD, val);
 177                         oprofile_add_data64(&entry, val);
 178                         if (ibs_state.branch_target) {
 179                                 rdmsrl(MSR_AMD64_IBSBRTARGET, val);
 180                                 oprofile_add_data(&entry, (unsigned long)val);
 181                         }
 182                         oprofile_write_commit(&entry);
 183
 184                         /* reenable the IRQ */
 185                         ctl = op_amd_randomize_ibs_op(ibs_state.ibs_op_ctl);
 186                         wrmsrl(MSR_AMD64_IBSOPCTL, ctl);
 187                 }
 188         }
 189 }
 190
 191 static inline void op_amd_start_ibs(void)
 192 {
 193         u64 val;
 194
 195         if (!ibs_caps)
 196                 return;
 197
 198         memset(&ibs_state, 0, sizeof(ibs_state));
 199
 200         /*
 201          * Note: Since the max count settings may out of range we
 202          * write back the actual used values so that userland can read
 203          * it.
 204          */
 205
 206         if (ibs_config.fetch_enabled) {
 207                 val = ibs_config.max_cnt_fetch >> 4;
 208                 val = min(val, IBS_FETCH_MAX_CNT);
 209                 ibs_config.max_cnt_fetch = val << 4;
 210                 val |= ibs_config.rand_en ? IBS_FETCH_RAND_EN : 0;
 211                 val |= IBS_FETCH_ENABLE;
 212                 wrmsrl(MSR_AMD64_IBSFETCHCTL, val);
 213         }
 214
 215         if (ibs_config.op_enabled) {
 216                 val = ibs_config.max_cnt_op >> 4;
 217                 if (!(ibs_caps & IBS_CAPS_RDWROPCNT)) {
 218                         /*
 219                          * IbsOpCurCnt not supported.  See
 220                          * op_amd_randomize_ibs_op() for details.
 221                          */
 222                         val = clamp(val, 0x0081ULL, 0xFF80ULL);
 223                         ibs_config.max_cnt_op = val << 4;
 224                 } else {
 225                         /*
 226                          * The start value is randomized with a
 227                          * positive offset, we need to compensate it
 228                          * with the half of the randomized range. Also
 229                          * avoid underflows.
 230                          */
 231                         val += IBS_RANDOM_MAXCNT_OFFSET;
 232                         if (ibs_caps & IBS_CAPS_OPCNTEXT)
 233                                 val = min(val, IBS_OP_MAX_CNT_EXT);
 234                         else
 235                                 val = min(val, IBS_OP_MAX_CNT);
 236                         ibs_config.max_cnt_op =
 237                                 (val - IBS_RANDOM_MAXCNT_OFFSET) << 4;
 238                 }
 239                 val = ((val & ~IBS_OP_MAX_CNT) << 4) | (val & IBS_OP_MAX_CNT);
 240                 val |= ibs_config.dispatched_ops ? IBS_OP_CNT_CTL : 0;
 241                 val |= IBS_OP_ENABLE;
 242                 ibs_state.ibs_op_ctl = val;
 243                 ibs_state.sample_size = IBS_OP_SIZE;
 244                 if (ibs_config.branch_target) {
 245                         ibs_state.branch_target = 1;
 246                         ibs_state.sample_size++;
 247                 }
 248                 val = op_amd_randomize_ibs_op(ibs_state.ibs_op_ctl);
 249                 wrmsrl(MSR_AMD64_IBSOPCTL, val);
 250         }
 251 }
 252
 253 static void op_amd_stop_ibs(void)
 254 {
 255         if (!ibs_caps)
 256                 return;
 257
 258         if (ibs_config.fetch_enabled)
 259                 /* clear max count and enable */
 260                 wrmsrl(MSR_AMD64_IBSFETCHCTL, 0);
 261
 262         if (ibs_config.op_enabled)
 263                 /* clear max count and enable */
 264                 wrmsrl(MSR_AMD64_IBSOPCTL, 0);
 265 }
 266
 267 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
 268
 269 static void op_mux_switch_ctrl(struct op_x86_model_spec const *model,
 270                                struct op_msrs const * const msrs)
 271 {
 272         u64 val;
 273         int i;
 274
 275         /* enable active counters */
 276         for (i = 0; i < num_counters; ++i) {
 277                 int virt = op_x86_phys_to_virt(i);
 278                 if (!reset_value[virt])
 279                         continue;
 280                 rdmsrl(msrs->controls[i].addr, val);
 281                 val &= model->reserved;
 282                 val |= op_x86_get_ctrl(model, &counter_config[virt]);
 283                 wrmsrl(msrs->controls[i].addr, val);
 284         }
 285 }
 286
 287 #endif
 288
 289 /* functions for op_amd_spec */
 290
 291 static void op_amd_shutdown(struct op_msrs const * const msrs)
 292 {
 293         int i;
 294
 295         for (i = 0; i < num_counters; ++i) {
 296                 if (!msrs->counters[i].addr)
 297                         continue;
 298                 release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
 299                 release_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
 300         }
 301 }
 302
 303 static int op_amd_fill_in_addresses(struct op_msrs * const msrs)
 304 {
 305         int i;
 306
 307         for (i = 0; i < num_counters; i++) {
 308                 if (!reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i))
 309                         goto fail;
 310                 if (!reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i)) {
 311                         release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
 312                         goto fail;
 313                 }
 314                 /* both registers must be reserved */
 315                 if (num_counters == AMD64_NUM_COUNTERS_F15H) {
 316                         msrs->counters[i].addr = MSR_F15H_PERF_CTR + (i << 1);
 317                         msrs->controls[i].addr = MSR_F15H_PERF_CTL + (i << 1);
 318                 } else {
 319                         msrs->controls[i].addr = MSR_K7_EVNTSEL0 + i;
 320                         msrs->counters[i].addr = MSR_K7_PERFCTR0 + i;
 321                 }
 322                 continue;
 323         fail:
 324                 if (!counter_config[i].enabled)
 325                         continue;
 326                 op_x86_warn_reserved(i);
 327                 op_amd_shutdown(msrs);
 328                 return -EBUSY;
 329         }
 330
 331         return 0;
 332 }
 333
 334 static void op_amd_setup_ctrs(struct op_x86_model_spec const *model,
 335                               struct op_msrs const * const msrs)
 336 {
 337         u64 val;
 338         int i;
 339
 340         /* setup reset_value */
 341         for (i = 0; i < OP_MAX_COUNTER; ++i) {
 342                 if (counter_config[i].enabled
 343                     && msrs->counters[op_x86_virt_to_phys(i)].addr)
 344                         reset_value[i] = counter_config[i].count;
 345                 else
 346                         reset_value[i] = 0;
 347         }
 348
 349         /* clear all counters */
 350         for (i = 0; i < num_counters; ++i) {
 351                 if (!msrs->controls[i].addr)
 352                         continue;
 353                 rdmsrl(msrs->controls[i].addr, val);
 354                 if (val & ARCH_PERFMON_EVENTSEL_ENABLE)
 355                         op_x86_warn_in_use(i);
 356                 val &= model->reserved;
 357                 wrmsrl(msrs->controls[i].addr, val);
 358                 /*
 359                  * avoid a false detection of ctr overflows in NMI
 360                  * handler
 361                  */
 362                 wrmsrl(msrs->counters[i].addr, -1LL);
 363         }
 364
 365         /* enable active counters */
 366         for (i = 0; i < num_counters; ++i) {
 367                 int virt = op_x86_phys_to_virt(i);
 368                 if (!reset_value[virt])
 369                         continue;
 370
 371                 /* setup counter registers */
 372                 wrmsrl(msrs->counters[i].addr, -(u64)reset_value[virt]);
 373
 374                 /* setup control registers */
 375                 rdmsrl(msrs->controls[i].addr, val);
 376                 val &= model->reserved;
 377                 val |= op_x86_get_ctrl(model, &counter_config[virt]);
 378                 wrmsrl(msrs->controls[i].addr, val);
 379         }
 380 }
 381
 382 static int op_amd_check_ctrs(struct pt_regs * const regs,
 383                              struct op_msrs const * const msrs)
 384 {
 385         u64 val;
 386         int i;
 387
 388         for (i = 0; i < num_counters; ++i) {
 389                 int virt = op_x86_phys_to_virt(i);
 390                 if (!reset_value[virt])
 391                         continue;
 392                 rdmsrl(msrs->counters[i].addr, val);
 393                 /* bit is clear if overflowed: */
 394                 if (val & OP_CTR_OVERFLOW)
 395                         continue;
 396                 oprofile_add_sample(regs, virt);
 397                 wrmsrl(msrs->counters[i].addr, -(u64)reset_value[virt]);
 398         }
 399
 400         op_amd_handle_ibs(regs, msrs);
 401
 402         /* See op_model_ppro.c */
 403         return 1;
 404 }
 405
 406 static void op_amd_start(struct op_msrs const * const msrs)
 407 {
 408         u64 val;
 409         int i;
 410
 411         for (i = 0; i < num_counters; ++i) {
 412                 if (!reset_value[op_x86_phys_to_virt(i)])
 413                         continue;
 414                 rdmsrl(msrs->controls[i].addr, val);
 415                 val |= ARCH_PERFMON_EVENTSEL_ENABLE;
 416                 wrmsrl(msrs->controls[i].addr, val);
 417         }
 418
 419         op_amd_start_ibs();
 420 }
 421
 422 static void op_amd_stop(struct op_msrs const * const msrs)
 423 {
 424         u64 val;
 425         int i;
 426
 427         /*
 428          * Subtle: stop on all counters to avoid race with setting our
 429          * pm callback
 430          */
 431         for (i = 0; i < num_counters; ++i) {
 432                 if (!reset_value[op_x86_phys_to_virt(i)])
 433                         continue;
 434                 rdmsrl(msrs->controls[i].addr, val);
 435                 val &= ~ARCH_PERFMON_EVENTSEL_ENABLE;
 436                 wrmsrl(msrs->controls[i].addr, val);
 437         }
 438
 439         op_amd_stop_ibs();
 440 }
 441
 442 /*
 443  * check and reserve APIC extended interrupt LVT offset for IBS if
 444  * available
 445  */
 446
 447 static void init_ibs(void)
 448 {
 449         ibs_caps = get_ibs_caps();
 450
 451         if (!ibs_caps)
 452                 return;
 453
 454         printk(KERN_INFO "oprofile: AMD IBS detected (0x%08x)\n", ibs_caps);
 455 }
 456
 457 static int (*create_arch_files)(struct super_block *sb, struct dentry *root);
 458
 459 static int setup_ibs_files(struct super_block *sb, struct dentry *root)
 460 {
 461         struct dentry *dir;
 462         int ret = 0;
 463
 464         /* architecture specific files */
 465         if (create_arch_files)
 466                 ret = create_arch_files(sb, root);
 467
 468         if (ret)
 469                 return ret;
 470
 471         if (!ibs_caps)
 472                 return ret;
 473
 474         /* model specific files */
 475
 476         /* setup some reasonable defaults */
 477         memset(&ibs_config, 0, sizeof(ibs_config));
 478         ibs_config.max_cnt_fetch = 250000;
 479         ibs_config.max_cnt_op = 250000;
 480
 481         if (ibs_caps & IBS_CAPS_FETCHSAM) {
 482                 dir = oprofilefs_mkdir(sb, root, "ibs_fetch");
 483                 oprofilefs_create_ulong(sb, dir, "enable",
 484                                         &ibs_config.fetch_enabled);
 485                 oprofilefs_create_ulong(sb, dir, "max_count",
 486                                         &ibs_config.max_cnt_fetch);
 487                 oprofilefs_create_ulong(sb, dir, "rand_enable",
 488                                         &ibs_config.rand_en);
 489         }
 490
 491         if (ibs_caps & IBS_CAPS_OPSAM) {
 492                 dir = oprofilefs_mkdir(sb, root, "ibs_op");
 493                 oprofilefs_create_ulong(sb, dir, "enable",
 494                                         &ibs_config.op_enabled);
 495                 oprofilefs_create_ulong(sb, dir, "max_count",
 496                                         &ibs_config.max_cnt_op);
 497                 if (ibs_caps & IBS_CAPS_OPCNT)
 498                         oprofilefs_create_ulong(sb, dir, "dispatched_ops",
 499                                                 &ibs_config.dispatched_ops);
 500                 if (ibs_caps & IBS_CAPS_BRNTRGT)
 501                         oprofilefs_create_ulong(sb, dir, "branch_target",
 502                                                 &ibs_config.branch_target);
 503         }
 504
 505         return 0;
 506 }
 507
 508 struct op_x86_model_spec op_amd_spec;
 509
 510 static int op_amd_init(struct oprofile_operations *ops)
 511 {
 512         init_ibs();
 513         create_arch_files = ops->create_files;
 514         ops->create_files = setup_ibs_files;
 515
 516         if (boot_cpu_data.x86 == 0x15) {
 517                 num_counters = AMD64_NUM_COUNTERS_F15H;
 518         } else {
 519                 num_counters = AMD64_NUM_COUNTERS;
 520         }
 521
 522         op_amd_spec.num_counters = num_counters;
 523         op_amd_spec.num_controls = num_counters;
 524         op_amd_spec.num_virt_counters = max(num_counters, NUM_VIRT_COUNTERS);
 525
 526         return 0;
 527 }
 528
 529 struct op_x86_model_spec op_amd_spec = {
 530         /* num_counters/num_controls filled in at runtime */
 531         .reserved               = MSR_AMD_EVENTSEL_RESERVED,
 532         .event_mask             = OP_EVENT_MASK,
 533         .init                   = op_amd_init,
 534         .fill_in_addresses      = &op_amd_fill_in_addresses,
 535         .setup_ctrs             = &op_amd_setup_ctrs,
 536         .check_ctrs             = &op_amd_check_ctrs,
 537         .start                  = &op_amd_start,
 538         .stop                   = &op_amd_stop,
 539         .shutdown               = &op_amd_shutdown,
 540 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
 541         .switch_ctrl            = &op_mux_switch_ctrl,
 542 #endif
 543 };