1/*- 2 * Copyright (c) 1996 Bruce D. Evans. 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#ifdef GUPROF 31#if 0 32#include "opt_i586_guprof.h" 33#include "opt_perfmon.h" 34#endif 35 36#include <sys/param.h> 37#include <sys/systm.h> 38#include <sys/bus.h> 39#include <sys/cpu.h> 40#include <sys/eventhandler.h> 41#include <sys/gmon.h> 42#include <sys/kernel.h> 43#include <sys/smp.h> 44#include <sys/sysctl.h> 45 46#include <machine/clock.h> 47#if 0 48#include <machine/perfmon.h> 49#endif 50#include <machine/timerreg.h> 51 52#define CPUTIME_CLOCK_UNINITIALIZED 0 53#define CPUTIME_CLOCK_I8254 1 54#define CPUTIME_CLOCK_TSC 2 55#define CPUTIME_CLOCK_I586_PMC 3 56#define CPUTIME_CLOCK_I8254_SHIFT 7 57 58int cputime_bias = 1; /* initialize for locality of reference */ 59 60static int cputime_clock = CPUTIME_CLOCK_UNINITIALIZED; 61#if defined(PERFMON) && defined(I586_PMC_GUPROF) 62static u_int cputime_clock_pmc_conf = I586_PMC_GUPROF; 63static int cputime_clock_pmc_init; 64static struct gmonparam saved_gmp; 65#endif 66static int cputime_prof_active; 67#endif /* GUPROF */ 68 69#ifdef __GNUCLIKE_ASM 70__asm(" \n\ 71GM_STATE = 0 \n\ 72GMON_PROF_OFF = 3 \n\ 73 \n\ 74 .text \n\ 75 .p2align 4,0x90 \n\ 76 .globl __mcount \n\ 77 .type __mcount,@function \n\ 78__mcount: \n\ 79 # \n\ 80 # Check that we are profiling. Do it early for speed. \n\ 81 # \n\ 82 cmpl $GMON_PROF_OFF,_gmonparam+GM_STATE \n\ 83 je .mcount_exit \n\ 84 # \n\ 85 # __mcount is the same as [.]mcount except the caller \n\ 86 # hasn't changed the stack except to call here, so the \n\ 87 # caller's raddr is above our raddr. \n\ 88 # \n\ 89 pushq %rax \n\ 90 pushq %rdx \n\ 91 pushq %rcx \n\ 92 pushq %rsi \n\ 93 pushq %rdi \n\ 94 pushq %r8 \n\ 95 pushq %r9 \n\ 96 movq 7*8+8(%rsp),%rdi \n\ 97 jmp .got_frompc \n\ 98 \n\ 99 .p2align 4,0x90 \n\ 100 .globl .mcount \n\ 101.mcount: \n\ 102 cmpl $GMON_PROF_OFF,_gmonparam+GM_STATE \n\ 103 je .mcount_exit \n\ 104 # \n\ 105 # The caller's stack frame has already been built, so \n\ 106 # %rbp is the caller's frame pointer. The caller's \n\ 107 # raddr is in the caller's frame following the caller's \n\ 108 # caller's frame pointer. \n\ 109 # \n\ 110 pushq %rax \n\ 111 pushq %rdx \n\ 112 pushq %rcx \n\ 113 pushq %rsi \n\ 114 pushq %rdi \n\ 115 pushq %r8 \n\ 116 pushq %r9 \n\ 117 movq 8(%rbp),%rdi \n\ 118.got_frompc: \n\ 119 # \n\ 120 # Our raddr is the caller's pc. \n\ 121 # \n\ 122 movq 7*8(%rsp),%rsi \n\ 123 \n\ 124 pushfq \n\ 125 cli \n\ 126 call mcount \n\ 127 popfq \n\ 128 popq %r9 \n\ 129 popq %r8 \n\ 130 popq %rdi \n\ 131 popq %rsi \n\ 132 popq %rcx \n\ 133 popq %rdx \n\ 134 popq %rax \n\ 135.mcount_exit: \n\ 136 ret $0 \n\ 137"); 138#else /* !__GNUCLIKE_ASM */ 139#error "this file needs to be ported to your compiler" 140#endif /* __GNUCLIKE_ASM */ 141 142#ifdef GUPROF 143/* 144 * [.]mexitcount saves the return register(s), loads selfpc and calls 145 * mexitcount(selfpc) to do the work. Someday it should be in a machine 146 * dependent file together with cputime(), __mcount and [.]mcount. cputime() 147 * can't just be put in machdep.c because it has to be compiled without -pg. 148 */ 149#ifdef __GNUCLIKE_ASM 150__asm(" \n\ 151 .text \n\ 152# \n\ 153# Dummy label to be seen when gprof -u hides [.]mexitcount. \n\ 154# \n\ 155 .p2align 4,0x90 \n\ 156 .globl __mexitcount \n\ 157 .type __mexitcount,@function \n\ 158__mexitcount: \n\ 159 nop \n\ 160 \n\ 161GMON_PROF_HIRES = 4 \n\ 162 \n\ 163 .p2align 4,0x90 \n\ 164 .globl .mexitcount \n\ 165.mexitcount: \n\ 166 cmpl $GMON_PROF_HIRES,_gmonparam+GM_STATE \n\ 167 jne .mexitcount_exit \n\ 168 pushq %rax \n\ 169 pushq %rdx \n\ 170 pushq %rcx \n\ 171 pushq %rsi \n\ 172 pushq %rdi \n\ 173 pushq %r8 \n\ 174 pushq %r9 \n\ 175 movq 7*8(%rsp),%rdi \n\ 176 pushfq \n\ 177 cli \n\ 178 call mexitcount \n\ 179 popfq \n\ 180 popq %r9 \n\ 181 popq %r8 \n\ 182 popq %rdi \n\ 183 popq %rsi \n\ 184 popq %rcx \n\ 185 popq %rdx \n\ 186 popq %rax \n\ 187.mexitcount_exit: \n\ 188 ret $0 \n\ 189"); 190#endif /* __GNUCLIKE_ASM */ 191 192/* 193 * Return the time elapsed since the last call. The units are machine- 194 * dependent. 195 */ 196int 197cputime() 198{ 199 u_int count; 200 int delta; 201#if defined(PERFMON) && defined(I586_PMC_GUPROF) && !defined(SMP) 202 u_quad_t event_count; 203#endif 204 u_char high, low; 205 static u_int prev_count; 206 207 if (cputime_clock == CPUTIME_CLOCK_TSC) { 208 /* 209 * Scale the TSC a little to make cputime()'s frequency 210 * fit in an int, assuming that the TSC frequency fits 211 * in a u_int. Use a fixed scale since dynamic scaling 212 * would be slower and we can't really use the low bit 213 * of precision. 214 */ 215 count = (u_int)rdtsc() & ~1u; 216 delta = (int)(count - prev_count) >> 1; 217 prev_count = count; 218 return (delta); 219 } 220#if defined(PERFMON) && defined(I586_PMC_GUPROF) && !defined(SMP) 221 if (cputime_clock == CPUTIME_CLOCK_I586_PMC) { 222 /* 223 * XXX permon_read() should be inlined so that the 224 * perfmon module doesn't need to be compiled with 225 * profiling disabled and so that it is fast. 226 */ 227 perfmon_read(0, &event_count); 228 229 count = (u_int)event_count; 230 delta = (int)(count - prev_count); 231 prev_count = count; 232 return (delta); 233 } 234#endif /* PERFMON && I586_PMC_GUPROF && !SMP */ 235 236 /* 237 * Read the current value of the 8254 timer counter 0. 238 */ 239 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH); 240 low = inb(TIMER_CNTR0); 241 high = inb(TIMER_CNTR0); 242 count = ((high << 8) | low) << CPUTIME_CLOCK_I8254_SHIFT; 243 244 /* 245 * The timer counts down from TIMER_CNTR0_MAX to 0 and then resets. 246 * While profiling is enabled, this routine is called at least twice 247 * per timer reset (for mcounting and mexitcounting hardclock()), 248 * so at most one reset has occurred since the last call, and one 249 * has occurred iff the current count is larger than the previous 250 * count. This allows counter underflow to be detected faster 251 * than in microtime(). 252 */ 253 delta = prev_count - count; 254 prev_count = count; 255 if ((int) delta <= 0) 256 return (delta + (i8254_max_count << CPUTIME_CLOCK_I8254_SHIFT)); 257 return (delta); 258} 259 260static int 261sysctl_machdep_cputime_clock(SYSCTL_HANDLER_ARGS) 262{ 263 int clock; 264 int error; 265#if defined(PERFMON) && defined(I586_PMC_GUPROF) 266 int event; 267 struct pmc pmc; 268#endif 269 270 clock = cputime_clock; 271#if defined(PERFMON) && defined(I586_PMC_GUPROF) 272 if (clock == CPUTIME_CLOCK_I586_PMC) { 273 pmc.pmc_val = cputime_clock_pmc_conf; 274 clock += pmc.pmc_event; 275 } 276#endif 277 error = sysctl_handle_opaque(oidp, &clock, sizeof clock, req); 278 if (error == 0 && req->newptr != NULL) { 279#if defined(PERFMON) && defined(I586_PMC_GUPROF) 280 if (clock >= CPUTIME_CLOCK_I586_PMC) { 281 event = clock - CPUTIME_CLOCK_I586_PMC; 282 if (event >= 256) 283 return (EINVAL); 284 pmc.pmc_num = 0; 285 pmc.pmc_event = event; 286 pmc.pmc_unit = 0; 287 pmc.pmc_flags = PMCF_E | PMCF_OS | PMCF_USR; 288 pmc.pmc_mask = 0; 289 cputime_clock_pmc_conf = pmc.pmc_val; 290 cputime_clock = CPUTIME_CLOCK_I586_PMC; 291 } else 292#endif 293 { 294 if (clock < 0 || clock >= CPUTIME_CLOCK_I586_PMC) 295 return (EINVAL); 296 cputime_clock = clock; 297 } 298 } 299 return (error); 300} 301 302SYSCTL_PROC(_machdep, OID_AUTO, cputime_clock, CTLTYPE_INT | CTLFLAG_RW, 303 0, sizeof(u_int), sysctl_machdep_cputime_clock, "I", ""); 304 305/* 306 * The start and stop routines need not be here since we turn off profiling 307 * before calling them. They are here for convenience. 308 */ 309 310void 311startguprof(gp) 312 struct gmonparam *gp; 313{ 314 uint64_t freq; 315 316 freq = atomic_load_acq_64(&tsc_freq); 317 if (cputime_clock == CPUTIME_CLOCK_UNINITIALIZED) { 318 if (freq != 0 && mp_ncpus == 1) 319 cputime_clock = CPUTIME_CLOCK_TSC; 320 else 321 cputime_clock = CPUTIME_CLOCK_I8254; 322 } 323 if (cputime_clock == CPUTIME_CLOCK_TSC) { 324 gp->profrate = freq >> 1; 325 cputime_prof_active = 1; 326 } else 327 gp->profrate = i8254_freq << CPUTIME_CLOCK_I8254_SHIFT; 328#if defined(PERFMON) && defined(I586_PMC_GUPROF) 329 if (cputime_clock == CPUTIME_CLOCK_I586_PMC) { 330 if (perfmon_avail() && 331 perfmon_setup(0, cputime_clock_pmc_conf) == 0) { 332 if (perfmon_start(0) != 0) 333 perfmon_fini(0); 334 else { 335 /* XXX 1 event == 1 us. */ 336 gp->profrate = 1000000; 337 338 saved_gmp = *gp; 339 340 /* Zap overheads. They are invalid. */ 341 gp->cputime_overhead = 0; 342 gp->mcount_overhead = 0; 343 gp->mcount_post_overhead = 0; 344 gp->mcount_pre_overhead = 0; 345 gp->mexitcount_overhead = 0; 346 gp->mexitcount_post_overhead = 0; 347 gp->mexitcount_pre_overhead = 0; 348 349 cputime_clock_pmc_init = TRUE; 350 } 351 } 352 } 353#endif /* PERFMON && I586_PMC_GUPROF */ 354 cputime_bias = 0; 355 cputime(); 356} 357 358void 359stopguprof(gp) 360 struct gmonparam *gp; 361{ 362#if defined(PERFMON) && defined(I586_PMC_GUPROF) 363 if (cputime_clock_pmc_init) { 364 *gp = saved_gmp; 365 perfmon_fini(0); 366 cputime_clock_pmc_init = FALSE; 367 } 368#endif 369 if (cputime_clock == CPUTIME_CLOCK_TSC) 370 cputime_prof_active = 0; 371} 372 373/* If the cpu frequency changed while profiling, report a warning. */ 374static void 375tsc_freq_changed(void *arg, const struct cf_level *level, int status) 376{ 377 378 /* 379 * If there was an error during the transition or 380 * TSC is P-state invariant, don't do anything. 381 */ 382 if (status != 0 || tsc_is_invariant) 383 return; 384 if (cputime_prof_active && cputime_clock == CPUTIME_CLOCK_TSC) 385 printf("warning: cpu freq changed while profiling active\n"); 386} 387 388EVENTHANDLER_DEFINE(cpufreq_post_change, tsc_freq_changed, NULL, 389 EVENTHANDLER_PRI_ANY); 390 391#endif /* GUPROF */ 392