sys/dev/hwpmc/hwpmc_tsc.c

   1 /*-
   2  * Copyright (c) 2008 Joseph Koshy
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include <sys/param.h>
  31 #include <sys/pmc.h>
  32 #include <sys/pmckern.h>
  33 #include <sys/systm.h>
  34
  35 #include <machine/specialreg.h>
  36
  37 /*
  38  * TSC support.
  39  */
  40
  41 #define TSC_CAPS        PMC_CAP_READ
  42
  43 struct tsc_descr {
  44         struct pmc_descr pm_descr;  /* "base class" */
  45 };
  46
  47 static struct tsc_descr tsc_pmcdesc[TSC_NPMCS] =
  48 {
  49     {
  50         .pm_descr =
  51         {
  52                 .pd_name  = "TSC",
  53                 .pd_class = PMC_CLASS_TSC,
  54                 .pd_caps  = TSC_CAPS,
  55                 .pd_width = 64
  56         }
  57     }
  58 };
  59
  60 /*
  61  * Per-CPU data structure for TSCs.
  62  */
  63
  64 struct tsc_cpu {
  65         struct pmc_hw   tc_hw;
  66 };
  67
  68 static struct tsc_cpu **tsc_pcpu;
  69
  70 static int
  71 tsc_allocate_pmc(int cpu, int ri, struct pmc *pm,
  72     const struct pmc_op_pmcallocate *a)
  73 {
  74         (void) cpu;
  75
  76         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
  77             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
  78         KASSERT(ri >= 0 && ri < TSC_NPMCS,
  79             ("[tsc,%d] illegal row index %d", __LINE__, ri));
  80
  81         if (a->pm_class != PMC_CLASS_TSC)
  82                 return (EINVAL);
  83
  84         if ((pm->pm_caps & TSC_CAPS) == 0)
  85                 return (EINVAL);
  86
  87         if ((pm->pm_caps & ~TSC_CAPS) != 0)
  88                 return (EPERM);
  89
  90         if (a->pm_ev != PMC_EV_TSC_TSC ||
  91             a->pm_mode != PMC_MODE_SC)
  92                 return (EINVAL);
  93
  94         return (0);
  95 }
  96
  97 static int
  98 tsc_config_pmc(int cpu, int ri, struct pmc *pm)
  99 {
 100         struct pmc_hw *phw;
 101
 102         PMCDBG(MDP,CFG,1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
 103
 104         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 105             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 106         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 107
 108         phw = &tsc_pcpu[cpu]->tc_hw;
 109
 110         KASSERT(pm == NULL || phw->phw_pmc == NULL,
 111             ("[tsc,%d] pm=%p phw->pm=%p hwpmc not unconfigured", __LINE__,
 112             pm, phw->phw_pmc));
 113
 114         phw->phw_pmc = pm;
 115
 116         return (0);
 117 }
 118
 119 static int
 120 tsc_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
 121 {
 122         int error;
 123         size_t copied;
 124         const struct tsc_descr *pd;
 125         struct pmc_hw *phw;
 126
 127         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 128             ("[tsc,%d] illegal CPU %d", __LINE__, cpu));
 129         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 130
 131         phw = &tsc_pcpu[cpu]->tc_hw;
 132         pd  = &tsc_pmcdesc[ri];
 133
 134         if ((error = copystr(pd->pm_descr.pd_name, pi->pm_name,
 135             PMC_NAME_MAX, &copied)) != 0)
 136                 return (error);
 137
 138         pi->pm_class = pd->pm_descr.pd_class;
 139
 140         if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
 141                 pi->pm_enabled = TRUE;
 142                 *ppmc          = phw->phw_pmc;
 143         } else {
 144                 pi->pm_enabled = FALSE;
 145                 *ppmc          = NULL;
 146         }
 147
 148         return (0);
 149 }
 150
 151 static int
 152 tsc_get_config(int cpu, int ri, struct pmc **ppm)
 153 {
 154         (void) ri;
 155
 156         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 157             ("[tsc,%d] illegal CPU %d", __LINE__, cpu));
 158         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 159
 160         *ppm = tsc_pcpu[cpu]->tc_hw.phw_pmc;
 161
 162         return (0);
 163 }
 164
 165 static int
 166 tsc_get_msr(int ri, uint32_t *msr)
 167 {
 168         (void) ri;
 169
 170         KASSERT(ri >= 0 && ri < TSC_NPMCS,
 171             ("[tsc,%d] ri %d out of range", __LINE__, ri));
 172
 173         *msr = MSR_TSC;
 174
 175         return (0);
 176 }
 177
 178 static int
 179 tsc_pcpu_fini(struct pmc_mdep *md, int cpu)
 180 {
 181         int ri;
 182         struct pmc_cpu *pc;
 183
 184         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 185             ("[tsc,%d] illegal cpu %d", __LINE__, cpu));
 186         KASSERT(tsc_pcpu[cpu] != NULL, ("[tsc,%d] null pcpu", __LINE__));
 187
 188         free(tsc_pcpu[cpu], M_PMC);
 189         tsc_pcpu[cpu] = NULL;
 190
 191         ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC].pcd_ri;
 192
 193         KASSERT(ri == 0 && ri < TSC_NPMCS, ("[tsc,%d] ri=%d", __LINE__,
 194             ri));
 195
 196         pc = pmc_pcpu[cpu];
 197         pc->pc_hwpmcs[ri] = NULL;
 198
 199         return (0);
 200 }
 201
 202 static int
 203 tsc_pcpu_init(struct pmc_mdep *md, int cpu)
 204 {
 205         int ri;
 206         struct pmc_cpu *pc;
 207         struct tsc_cpu *tsc_pc;
 208
 209
 210         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 211             ("[tsc,%d] illegal cpu %d", __LINE__, cpu));
 212         KASSERT(tsc_pcpu, ("[tsc,%d] null pcpu", __LINE__));
 213         KASSERT(tsc_pcpu[cpu] == NULL, ("[tsc,%d] non-null per-cpu",
 214             __LINE__));
 215
 216         tsc_pc = malloc(sizeof(struct tsc_cpu), M_PMC, M_WAITOK|M_ZERO);
 217
 218         tsc_pc->tc_hw.phw_state = PMC_PHW_FLAG_IS_ENABLED |
 219             PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(0) |
 220             PMC_PHW_FLAG_IS_SHAREABLE;
 221
 222         tsc_pcpu[cpu] = tsc_pc;
 223
 224         ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC].pcd_ri;
 225
 226         KASSERT(pmc_pcpu, ("[tsc,%d] null generic pcpu", __LINE__));
 227
 228         pc = pmc_pcpu[cpu];
 229
 230         KASSERT(pc, ("[tsc,%d] null generic per-cpu", __LINE__));
 231
 232         pc->pc_hwpmcs[ri] = &tsc_pc->tc_hw;
 233
 234         return (0);
 235 }
 236
 237 static int
 238 tsc_read_pmc(int cpu, int ri, pmc_value_t *v)
 239 {
 240         struct pmc *pm;
 241         enum pmc_mode mode;
 242         const struct pmc_hw *phw;
 243
 244         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 245             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 246         KASSERT(ri == 0, ("[tsc,%d] illegal ri %d", __LINE__, ri));
 247
 248         phw = &tsc_pcpu[cpu]->tc_hw;
 249         pm  = phw->phw_pmc;
 250
 251         KASSERT(pm != NULL,
 252             ("[tsc,%d] no owner for PHW [cpu%d,pmc%d]", __LINE__, cpu, ri));
 253
 254         mode = PMC_TO_MODE(pm);
 255
 256         KASSERT(mode == PMC_MODE_SC,
 257             ("[tsc,%d] illegal pmc mode %d", __LINE__, mode));
 258
 259         PMCDBG(MDP,REA,1,"tsc-read id=%d", ri);
 260
 261         *v = rdtsc();
 262
 263         return (0);
 264 }
 265
 266 static int
 267 tsc_release_pmc(int cpu, int ri, struct pmc *pmc)
 268 {
 269         struct pmc_hw *phw;
 270
 271         (void) pmc;
 272
 273         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 274             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 275         KASSERT(ri == 0,
 276             ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 277
 278         phw = &tsc_pcpu[cpu]->tc_hw;
 279
 280         KASSERT(phw->phw_pmc == NULL,
 281             ("[tsc,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
 282
 283         /*
 284          * Nothing to do.
 285          */
 286         return (0);
 287 }
 288
 289 static int
 290 tsc_start_pmc(int cpu, int ri)
 291 {
 292         (void) cpu;
 293
 294         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 295             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 296         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 297
 298         return (0);     /* TSCs are always running. */
 299 }
 300
 301 static int
 302 tsc_stop_pmc(int cpu, int ri)
 303 {
 304         (void) cpu; (void) ri;
 305
 306         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 307             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 308         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 309
 310         return (0);     /* Cannot actually stop a TSC. */
 311 }
 312
 313 static int
 314 tsc_write_pmc(int cpu, int ri, pmc_value_t v)
 315 {
 316         (void) cpu; (void) ri; (void) v;
 317
 318         KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
 319             ("[tsc,%d] illegal CPU value %d", __LINE__, cpu));
 320         KASSERT(ri == 0, ("[tsc,%d] illegal row-index %d", __LINE__, ri));
 321
 322         /*
 323          * The TSCs are used as timecounters by the kernel, so even
 324          * though some i386 CPUs support writeable TSCs, we don't
 325          * support writing changing TSC values through the HWPMC API.
 326          */
 327         return (0);
 328 }
 329
 330 int
 331 pmc_tsc_initialize(struct pmc_mdep *md, int maxcpu)
 332 {
 333         struct pmc_classdep *pcd;
 334
 335         KASSERT(md != NULL, ("[tsc,%d] md is NULL", __LINE__));
 336         KASSERT(md->pmd_nclass >= 1, ("[tsc,%d] dubious md->nclass %d",
 337             __LINE__, md->pmd_nclass));
 338
 339         tsc_pcpu = malloc(sizeof(struct tsc_cpu *) * maxcpu, M_PMC,
 340             M_ZERO|M_WAITOK);
 341
 342         pcd = &md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC];
 343
 344         pcd->pcd_caps   = PMC_CAP_READ;
 345         pcd->pcd_class  = PMC_CLASS_TSC;
 346         pcd->pcd_num    = TSC_NPMCS;
 347         pcd->pcd_ri     = md->pmd_npmc;
 348         pcd->pcd_width  = 64;
 349
 350         pcd->pcd_allocate_pmc = tsc_allocate_pmc;
 351         pcd->pcd_config_pmc   = tsc_config_pmc;
 352         pcd->pcd_describe     = tsc_describe;
 353         pcd->pcd_get_config   = tsc_get_config;
 354         pcd->pcd_get_msr      = tsc_get_msr;
 355         pcd->pcd_pcpu_init    = tsc_pcpu_init;
 356         pcd->pcd_pcpu_fini    = tsc_pcpu_fini;
 357         pcd->pcd_read_pmc     = tsc_read_pmc;
 358         pcd->pcd_release_pmc  = tsc_release_pmc;
 359         pcd->pcd_start_pmc    = tsc_start_pmc;
 360         pcd->pcd_stop_pmc     = tsc_stop_pmc;
 361         pcd->pcd_write_pmc    = tsc_write_pmc;
 362
 363         md->pmd_npmc += TSC_NPMCS;
 364
 365         return (0);
 366 }
 367
 368 void
 369 pmc_tsc_finalize(struct pmc_mdep *md)
 370 {
 371 #ifdef  INVARIANTS
 372         int i, ncpus;
 373
 374         ncpus = pmc_cpu_max();
 375         for (i = 0; i < ncpus; i++)
 376                 KASSERT(tsc_pcpu[i] == NULL, ("[tsc,%d] non-null pcpu cpu %d",
 377                     __LINE__, i));
 378
 379         KASSERT(md->pmd_classdep[PMC_MDEP_CLASS_INDEX_TSC].pcd_class ==
 380             PMC_CLASS_TSC, ("[tsc,%d] class mismatch", __LINE__));
 381
 382 #else
 383         (void) md;
 384 #endif
 385
 386         free(tsc_pcpu, M_PMC);
 387         tsc_pcpu = NULL;
 388 }