sys/dev/hwpmc/hwpmc_tsc.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2008 Joseph Koshy
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/param.h>
  33 #include <sys/pmc.h>
  34 #include <sys/pmckern.h>
  35 #include <sys/systm.h>
  36
  37 #include <machine/specialreg.h>
  38
  39 /*
  40  * TSC support.
  41  */
  42
  43 #define TSC_CAPS        PMC_CAP_READ
  44
  45 struct tsc_descr {
  46         struct pmc_descr pm_descr;  /* "base class" */
  47 };
  48
  49 static struct tsc_descr tsc_pmcdesc[TSC_NPMCS] =
  50 {
  51     {
  52         .pm_descr =
  53         {
  54                 .pd_name  = "TSC",
  55                 .pd_class = PMC_CLASS_TSC,
  56                 .pd_caps  = TSC_CAPS,
  57                 .pd_width = 64
  58         }
  59     }
  60 };
  61
  62 /*
  63  * Per-CPU data structure for TSCs.
  64  */
  65
  66 struct tsc_cpu {
  67         struct pmc_hw   tc_hw;
  68 };
  69
  70 static struct tsc_cpu **tsc_pcpu;
  71
  72 static int
  73 tsc_allocate_pmc(int cpu, int ri, struct pmc *pm,
  74     const struct pmc_op_pmcallocate *a)
  75 {
  76         (void) cpu;
  77
  78         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
  79             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
  80         KASSERT(ri >= 0 && ri < TSC_NPMCS,
  81             ("[tsc,%d] illegal row index %d", __LINE__, ri));
  82
  83         if (a->pm_class != PMC_CLASS_TSC)
  84                 return (EINVAL);
  85
  86         if ((pm->pm_caps & TSC_CAPS) == 0)
  87                 return (EINVAL);
  88
  89         if ((pm->pm_caps & ~TSC_CAPS) != 0)
  90                 return (EPERM);
  91
  92         if (a->pm_ev != PMC_EV_TSC_TSC ||
  93             a->pm_mode != PMC_MODE_SC)
  94                 return (EINVAL);
  95
  96         return (0);
  97 }
  98
  99 static int
 100 tsc_config_pmc(int cpu, int ri, struct pmc *pm)
 101 {
 102         struct pmc_hw *phw;
 103
 104         PMCDBG3(MDP,CFG,1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
 105
 106         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 107             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 108         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 109
 110         phw = &tsc_pcpu[cpu]->tc_hw;
 111
 112         KASSERT(pm == NULL || phw->phw_pmc == NULL,
 113             ("[tsc,%d] pm=%p phw->pm=%p hwpmc not unconfigured", __LINE__,
 114             pm, phw->phw_pmc));
 115
 116         phw->phw_pmc = pm;
 117
 118         return (0);
 119 }
 120
 121 static int
 122 tsc_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
 123 {
 124         int error;
 125         size_t copied;
 126         const struct tsc_descr *pd;
 127         struct pmc_hw *phw;
 128
 129         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 130             ("[tsc,%d] illegal CPU %d", __LINE__, cpu));
 131         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 132
 133         phw = &tsc_pcpu[cpu]->tc_hw;
 134         pd  = &tsc_pmcdesc[ri];
 135
 136         if ((error = copystr(pd->pm_descr.pd_name, pi->pm_name,
 137             PMC_NAME_MAX, &copied)) != 0)
 138                 return (error);
 139
 140         pi->pm_class = pd->pm_descr.pd_class;
 141
 142         if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
 143                 pi->pm_enabled = TRUE;
 144                 *ppmc          = phw->phw_pmc;
 145         } else {
 146                 pi->pm_enabled = FALSE;
 147                 *ppmc          = NULL;
 148         }
 149
 150         return (0);
 151 }
 152
 153 static int
 154 tsc_get_config(int cpu, int ri, struct pmc **ppm)
 155 {
 156         (void) ri;
 157
 158         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 159             ("[tsc,%d] illegal CPU %d", __LINE__, cpu));
 160         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 161
 162         *ppm = tsc_pcpu[cpu]->tc_hw.phw_pmc;
 163
 164         return (0);
 165 }
 166
 167 static int
 168 tsc_get_msr(int ri, uint32_t *msr)
 169 {
 170         (void) ri;
 171
 172         KASSERT(ri >= 0 && ri < TSC_NPMCS,
 173             ("[tsc,%d] ri %d out of range", __LINE__, ri));
 174
 175         *msr = MSR_TSC;
 176
 177         return (0);
 178 }
 179
 180 static int
 181 tsc_pcpu_fini(struct pmc_mdep *md, int cpu)
 182 {
 183         int ri;
 184         struct pmc_cpu *pc;
 185
 186         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 187             ("[tsc,%d] illegal cpu %d", __LINE__, cpu));
 188         KASSERT(tsc_pcpu[cpu] != NULL, ("[tsc,%d] null pcpu", __LINE__));
 189
 190         free(tsc_pcpu[cpu], M_PMC);
 191         tsc_pcpu[cpu] = NULL;
 192
 193         ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC].pcd_ri;
 194
 195         pc = pmc_pcpu[cpu];
 196         pc->pc_hwpmcs[ri] = NULL;
 197
 198         return (0);
 199 }
 200
 201 static int
 202 tsc_pcpu_init(struct pmc_mdep *md, int cpu)
 203 {
 204         int ri;
 205         struct pmc_cpu *pc;
 206         struct tsc_cpu *tsc_pc;
 207
 208
 209         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 210             ("[tsc,%d] illegal cpu %d", __LINE__, cpu));
 211         KASSERT(tsc_pcpu, ("[tsc,%d] null pcpu", __LINE__));
 212         KASSERT(tsc_pcpu[cpu] == NULL, ("[tsc,%d] non-null per-cpu",
 213             __LINE__));
 214
 215         tsc_pc = malloc(sizeof(struct tsc_cpu), M_PMC, M_WAITOK|M_ZERO);
 216
 217         tsc_pc->tc_hw.phw_state = PMC_PHW_FLAG_IS_ENABLED |
 218             PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(0) |
 219             PMC_PHW_FLAG_IS_SHAREABLE;
 220
 221         tsc_pcpu[cpu] = tsc_pc;
 222
 223         ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC].pcd_ri;
 224
 225         KASSERT(pmc_pcpu, ("[tsc,%d] null generic pcpu", __LINE__));
 226
 227         pc = pmc_pcpu[cpu];
 228
 229         KASSERT(pc, ("[tsc,%d] null generic per-cpu", __LINE__));
 230
 231         pc->pc_hwpmcs[ri] = &tsc_pc->tc_hw;
 232
 233         return (0);
 234 }
 235
 236 static int
 237 tsc_read_pmc(int cpu, int ri, pmc_value_t *v)
 238 {
 239         struct pmc *pm;
 240         enum pmc_mode mode;
 241         const struct pmc_hw *phw;
 242
 243         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 244             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 245         KASSERT(ri == 0, ("[tsc,%d] illegal ri %d", __LINE__, ri));
 246
 247         phw = &tsc_pcpu[cpu]->tc_hw;
 248         pm  = phw->phw_pmc;
 249
 250         KASSERT(pm != NULL,
 251             ("[tsc,%d] no owner for PHW [cpu%d,pmc%d]", __LINE__, cpu, ri));
 252
 253         mode = PMC_TO_MODE(pm);
 254
 255         KASSERT(mode == PMC_MODE_SC,
 256             ("[tsc,%d] illegal pmc mode %d", __LINE__, mode));
 257
 258         PMCDBG1(MDP,REA,1,"tsc-read id=%d", ri);
 259
 260         *v = rdtsc();
 261
 262         return (0);
 263 }
 264
 265 static int
 266 tsc_release_pmc(int cpu, int ri, struct pmc *pmc)
 267 {
 268         struct pmc_hw *phw;
 269
 270         (void) pmc;
 271
 272         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 273             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 274         KASSERT(ri == 0,
 275             ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 276
 277         phw = &tsc_pcpu[cpu]->tc_hw;
 278
 279         KASSERT(phw->phw_pmc == NULL,
 280             ("[tsc,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
 281
 282         /*
 283          * Nothing to do.
 284          */
 285         return (0);
 286 }
 287
 288 static int
 289 tsc_start_pmc(int cpu, int ri)
 290 {
 291         (void) cpu;
 292
 293         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 294             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 295         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 296
 297         return (0);     /* TSCs are always running. */
 298 }
 299
 300 static int
 301 tsc_stop_pmc(int cpu, int ri)
 302 {
 303         (void) cpu; (void) ri;
 304
 305         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 306             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 307         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 308
 309         return (0);     /* Cannot actually stop a TSC. */
 310 }
 311
 312 static int
 313 tsc_write_pmc(int cpu, int ri, pmc_value_t v)
 314 {
 315         (void) cpu; (void) ri; (void) v;
 316
 317         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 318             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 319         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 320
 321         /*
 322          * The TSCs are used as timecounters by the kernel, so even
 323          * though some i386 CPUs support writeable TSCs, we don't
 324          * support writing changing TSC values through the HWPMC API.
 325          */
 326         return (0);
 327 }
 328
 329 int
 330 pmc_tsc_initialize(struct pmc_mdep *md, int maxcpu)
 331 {
 332         struct pmc_classdep *pcd;
 333
 334         KASSERT(md != NULL, ("[tsc,%d] md is NULL", __LINE__));
 335         KASSERT(md->pmd_nclass >= 1, ("[tsc,%d] dubious md->nclass %d",
 336             __LINE__, md->pmd_nclass));
 337
 338         tsc_pcpu = malloc(sizeof(struct tsc_cpu *) * maxcpu, M_PMC,
 339             M_ZERO|M_WAITOK);
 340
 341         pcd = &md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC];
 342
 343         pcd->pcd_caps   = PMC_CAP_READ;
 344         pcd->pcd_class  = PMC_CLASS_TSC;
 345         pcd->pcd_num    = TSC_NPMCS;
 346         pcd->pcd_ri     = md->pmd_npmc;
 347         pcd->pcd_width  = 64;
 348
 349         pcd->pcd_allocate_pmc = tsc_allocate_pmc;
 350         pcd->pcd_config_pmc   = tsc_config_pmc;
 351         pcd->pcd_describe     = tsc_describe;
 352         pcd->pcd_get_config   = tsc_get_config;
 353         pcd->pcd_get_msr      = tsc_get_msr;
 354         pcd->pcd_pcpu_init    = tsc_pcpu_init;
 355         pcd->pcd_pcpu_fini    = tsc_pcpu_fini;
 356         pcd->pcd_read_pmc     = tsc_read_pmc;
 357         pcd->pcd_release_pmc  = tsc_release_pmc;
 358         pcd->pcd_start_pmc    = tsc_start_pmc;
 359         pcd->pcd_stop_pmc     = tsc_stop_pmc;
 360         pcd->pcd_write_pmc    = tsc_write_pmc;
 361
 362         md->pmd_npmc += TSC_NPMCS;
 363
 364         return (0);
 365 }
 366
 367 void
 368 pmc_tsc_finalize(struct pmc_mdep *md)
 369 {
 370 #ifdef  INVARIANTS
 371         int i, ncpus;
 372
 373         ncpus = pmc_cpu_max();
 374         for (i = 0; i < ncpus; i++)
 375                 KASSERT(tsc_pcpu[i] == NULL, ("[tsc,%d] non-null pcpu cpu %d",
 376                     __LINE__, i));
 377
 378         KASSERT(md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC].pcd_class ==
 379             PMC_CLASS_TSC, ("[tsc,%d] class mismatch", __LINE__));
 380
 381 #else
 382         (void) md;
 383 #endif
 384
 385         free(tsc_pcpu, M_PMC);
 386         tsc_pcpu = NULL;
 387 }