2 * Copyright (c) 1996 Bruce D. Evans.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
32 #include "opt_i586_guprof.h"
33 #include "opt_perfmon.h"
36 #include <sys/param.h>
37 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/sysctl.h>
42 #include <machine/clock.h>
44 #include <machine/perfmon.h>
46 #include <machine/profile.h>
50 #include <machine/asmacros.h>
51 #include <machine/timerreg.h>
54 #define CPUTIME_CLOCK_UNINITIALIZED 0
55 #define CPUTIME_CLOCK_I8254 1
56 #define CPUTIME_CLOCK_TSC 2
57 #define CPUTIME_CLOCK_I586_PMC 3
58 #define CPUTIME_CLOCK_I8254_SHIFT 7
60 int cputime_bias = 1; /* initialize for locality of reference */
62 static int cputime_clock = CPUTIME_CLOCK_UNINITIALIZED;
63 #ifdef I586_PMC_GUPROF
64 static u_int cputime_clock_pmc_conf = I586_PMC_GUPROF;
65 static int cputime_clock_pmc_init;
66 static struct gmonparam saved_gmp;
78 .type __mcount,@function \n\
81 # Check that we are profiling. Do it early for speed. \n\
83 cmpl $GMON_PROF_OFF," __XSTRING(CNAME(_gmonparam)) "+GM_STATE \n\
86 # __mcount is the same as [.]mcount except the caller \n\
87 # hasn't changed the stack except to call here, so the \n\
88 # caller's raddr is above our raddr. \n\
97 movq 7*8+8(%rsp),%rdi \n\
101 .globl " __XSTRING(HIDENAME(mcount)) " \n\
102 " __XSTRING(HIDENAME(mcount)) ": \n\
103 .globl __cyg_profile_func_enter \n\
104 __cyg_profile_func_enter: \n\
105 cmpl $GMON_PROF_OFF," __XSTRING(CNAME(_gmonparam)) "+GM_STATE \n\
108 # The caller's stack frame has already been built, so \n\
109 # %rbp is the caller's frame pointer. The caller's \n\
110 # raddr is in the caller's frame following the caller's \n\
111 # caller's frame pointer. \n\
120 movq 8(%rbp),%rdi \n\
123 # Our raddr is the caller's pc. \n\
125 movq 7*8(%rsp),%rsi \n\
129 call " __XSTRING(CNAME(mcount)) " \n\
141 #else /* !__GNUCLIKE_ASM */
142 #error this file needs to be ported to your compiler
143 #endif /* __GNUCLIKE_ASM */
147 * [.]mexitcount saves the return register(s), loads selfpc and calls
148 * mexitcount(selfpc) to do the work. Someday it should be in a machine
149 * dependent file together with cputime(), __mcount and [.]mcount. cputime()
150 * can't just be put in machdep.c because it has to be compiled without -pg.
152 #ifdef __GNUCLIKE_ASM
156 # Dummy label to be seen when gprof -u hides [.]mexitcount. \n\
159 .globl __mexitcount \n\
160 .type __mexitcount,@function \n\
164 GMON_PROF_HIRES = 4 \n\
167 .globl " __XSTRING(HIDENAME(mexitcount)) " \n\
168 " __XSTRING(HIDENAME(mexitcount)) ": \n\
169 .globl __cyg_profile_func_exit \n\
170 __cyg_profile_func_exit: \n\
171 cmpl $GMON_PROF_HIRES," __XSTRING(CNAME(_gmonparam)) "+GM_STATE \n\
172 jne .mexitcount_exit \n\
180 movq 7*8(%rsp),%rdi \n\
183 call " __XSTRING(CNAME(mexitcount)) " \n\
192 .mexitcount_exit: \n\
195 #else /* !__GNUCLIKE_ASM */
196 #error this file needs to be ported to your compiler
197 #endif /* __GNUCLIKE_ASM */
200 * Return the time elapsed since the last call. The units are machine-
208 #if (defined(I586_CPU) || defined(I686_CPU)) && !defined(SMP) && \
209 defined(PERFMON) && defined(I586_PMC_GUPROF)
210 u_quad_t event_count;
213 static u_int prev_count;
216 if (cputime_clock == CPUTIME_CLOCK_TSC) {
218 * Scale the TSC a little to make cputime()'s frequency
219 * fit in an int, assuming that the TSC frequency fits
220 * in a u_int. Use a fixed scale since dynamic scaling
221 * would be slower and we can't really use the low bit
224 count = (u_int)rdtsc() & ~1u;
225 delta = (int)(count - prev_count) >> 1;
229 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
230 if (cputime_clock == CPUTIME_CLOCK_I586_PMC) {
232 * XXX permon_read() should be inlined so that the
233 * perfmon module doesn't need to be compiled with
234 * profiling disabled and so that it is fast.
236 perfmon_read(0, &event_count);
238 count = (u_int)event_count;
239 delta = (int)(count - prev_count);
243 #endif /* PERFMON && I586_PMC_GUPROF */
247 * Read the current value of the 8254 timer counter 0.
249 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
250 low = inb(TIMER_CNTR0);
251 high = inb(TIMER_CNTR0);
252 count = ((high << 8) | low) << CPUTIME_CLOCK_I8254_SHIFT;
255 * The timer counts down from TIMER_CNTR0_MAX to 0 and then resets.
256 * While profiling is enabled, this routine is called at least twice
257 * per timer reset (for mcounting and mexitcounting hardclock()),
258 * so at most one reset has occurred since the last call, and one
259 * has occurred iff the current count is larger than the previous
260 * count. This allows counter underflow to be detected faster
261 * than in microtime().
263 delta = prev_count - count;
265 if ((int) delta <= 0)
266 return (delta + (timer0_max_count << CPUTIME_CLOCK_I8254_SHIFT));
271 sysctl_machdep_cputime_clock(SYSCTL_HANDLER_ARGS)
275 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
280 clock = cputime_clock;
281 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
282 if (clock == CPUTIME_CLOCK_I586_PMC) {
283 pmc.pmc_val = cputime_clock_pmc_conf;
284 clock += pmc.pmc_event;
287 error = sysctl_handle_opaque(oidp, &clock, sizeof clock, req);
288 if (error == 0 && req->newptr != NULL) {
289 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
290 if (clock >= CPUTIME_CLOCK_I586_PMC) {
291 event = clock - CPUTIME_CLOCK_I586_PMC;
295 pmc.pmc_event = event;
297 pmc.pmc_flags = PMCF_E | PMCF_OS | PMCF_USR;
299 cputime_clock_pmc_conf = pmc.pmc_val;
300 cputime_clock = CPUTIME_CLOCK_I586_PMC;
304 if (clock < 0 || clock >= CPUTIME_CLOCK_I586_PMC)
306 cputime_clock = clock;
312 SYSCTL_PROC(_machdep, OID_AUTO, cputime_clock, CTLTYPE_INT | CTLFLAG_RW,
313 0, sizeof(u_int), sysctl_machdep_cputime_clock, "I", "");
316 * The start and stop routines need not be here since we turn off profiling
317 * before calling them. They are here for convenience.
322 struct gmonparam *gp;
324 if (cputime_clock == CPUTIME_CLOCK_UNINITIALIZED) {
325 cputime_clock = CPUTIME_CLOCK_I8254;
328 cputime_clock = CPUTIME_CLOCK_TSC;
331 gp->profrate = timer_freq << CPUTIME_CLOCK_I8254_SHIFT;
333 if (cputime_clock == CPUTIME_CLOCK_TSC)
334 gp->profrate = tsc_freq >> 1;
335 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
336 else if (cputime_clock == CPUTIME_CLOCK_I586_PMC) {
337 if (perfmon_avail() &&
338 perfmon_setup(0, cputime_clock_pmc_conf) == 0) {
339 if (perfmon_start(0) != 0)
342 /* XXX 1 event == 1 us. */
343 gp->profrate = 1000000;
347 /* Zap overheads. They are invalid. */
348 gp->cputime_overhead = 0;
349 gp->mcount_overhead = 0;
350 gp->mcount_post_overhead = 0;
351 gp->mcount_pre_overhead = 0;
352 gp->mexitcount_overhead = 0;
353 gp->mexitcount_post_overhead = 0;
354 gp->mexitcount_pre_overhead = 0;
356 cputime_clock_pmc_init = TRUE;
360 #endif /* PERFMON && I586_PMC_GUPROF */
368 struct gmonparam *gp;
370 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
371 if (cputime_clock_pmc_init) {
374 cputime_clock_pmc_init = FALSE;
380 #ifdef __GNUCLIKE_ASM
384 .globl " __XSTRING(HIDENAME(mexitcount)) " \n\
385 " __XSTRING(HIDENAME(mexitcount)) ": \n\
388 #else /* !__GNUCLIKE_ASM */
389 #error this file needs to be ported to your compiler
390 #endif /* __GNUCLIKE_ASM */