The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/prof_machdep.c

Version: -  FREEBSD  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-2  -  FREEBSD-11-1  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-4  -  FREEBSD-10-3  -  FREEBSD-10-2  -  FREEBSD-10-1  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-3  -  FREEBSD-9-2  -  FREEBSD-9-1  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-4  -  FREEBSD-8-3  -  FREEBSD-8-2  -  FREEBSD-8-1  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-4  -  FREEBSD-7-3  -  FREEBSD-7-2  -  FREEBSD-7-1  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-4  -  FREEBSD-6-3  -  FREEBSD-6-2  -  FREEBSD-6-1  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-5  -  FREEBSD-5-4  -  FREEBSD-5-3  -  FREEBSD-5-2  -  FREEBSD-5-1  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    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: stable/11/sys/amd64/amd64/prof_machdep.c 331722 2018-03-29 02:50:57Z eadler $");
   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 
   58 int     cputime_bias = 1;       /* initialize for locality of reference */
   59 
   60 static int      cputime_clock = CPUTIME_CLOCK_UNINITIALIZED;
   61 #if defined(PERFMON) && defined(I586_PMC_GUPROF)
   62 static u_int    cputime_clock_pmc_conf = I586_PMC_GUPROF;
   63 static int      cputime_clock_pmc_init;
   64 static struct gmonparam saved_gmp;
   65 #endif
   66 static int      cputime_prof_active;
   67 #endif /* GUPROF */
   68 
   69 #ifdef __GNUCLIKE_ASM
   70 __asm("                                                         \n\
   71 GM_STATE        =       0                                       \n\
   72 GMON_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\
  161 GMON_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  */
  196 int
  197 cputime()
  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 
  260 static int
  261 sysctl_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 
  302 SYSCTL_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 
  310 void
  311 startguprof(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 
  358 void
  359 stopguprof(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. */
  374 static void
  375 tsc_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 
  388 EVENTHANDLER_DEFINE(cpufreq_post_change, tsc_freq_changed, NULL,
  389     EVENTHANDLER_PRI_ANY);
  390 
  391 #endif /* GUPROF */

Cache object: ca331d1eec5339fd67d810ee4dbb3556


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.