osfmk/kern/mach_clock.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * Mach Operating System
  27  * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
  28  * All Rights Reserved.
  29  *
  30  * Permission to use, copy, modify and distribute this software and its
  31  * documentation is hereby granted, provided that both the copyright
  32  * notice and this permission notice appear in all copies of the
  33  * software, derivative works or modified versions, and any portions
  34  * thereof, and that both notices appear in supporting documentation.
  35  *
  36  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39  *
  40  * Carnegie Mellon requests users of this software to return to
  41  *
  42  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43  *  School of Computer Science
  44  *  Carnegie Mellon University
  45  *  Pittsburgh PA 15213-3890
  46  *
  47  * any improvements or extensions that they make and grant Carnegie Mellon
  48  * the rights to redistribute these changes.
  49  */
  50 /*
  51  */
  52 /*
  53  *      File:   clock_prim.c
  54  *      Author: Avadis Tevanian, Jr.
  55  *      Date:   1986
  56  *
  57  *      Clock primitives.
  58  */
  59 #include <cpus.h>
  60 #include <stat_time.h>
  61 #include <mach_prof.h>
  62 #include <gprof.h>
  63
  64 #include <mach/boolean.h>
  65 #include <mach/machine.h>
  66 #include <mach/time_value.h>
  67 #include <mach/vm_param.h>
  68 #include <mach/vm_prot.h>
  69 #include <kern/clock.h>
  70 #include <kern/counters.h>
  71 #include <kern/cpu_number.h>
  72 #include <kern/host.h>
  73 #include <kern/lock.h>
  74 #include <kern/mach_param.h>
  75 #include <kern/misc_protos.h>
  76 #include <kern/processor.h>
  77 #include <kern/profile.h>
  78 #include <kern/sched.h>
  79 #include <kern/sched_prim.h>
  80 #include <kern/spl.h>
  81 #include <kern/thread.h>
  82 #include <kern/thread_swap.h>
  83 #include <kern/time_out.h>
  84 #include <vm/vm_kern.h>                                 /* kernel_map */
  85 #include <machine/mach_param.h>                 /* HZ */
  86
  87 #include <mach/clock_server.h>
  88 #include <mach/clock_priv_server.h>
  89 #include <mach/mach_host_server.h>
  90
  91 #include <profiling/profile-mk.h>
  92
  93 #if     STAT_TIME
  94 #define TICKBUMP(t)     timer_bump(t, (1000000/HZ))
  95 #else
  96 #define TICKBUMP(t)
  97 #endif
  98
  99 boolean_t       profile_kernel_services = TRUE; /* Indicates wether or not we
 100                                                                                          * account kernel services
 101                                                                                          * samples for user task */
 102
 103 /*
 104  * Hertz rate clock interrupt servicing. Primarily used to
 105  * update CPU statistics, recompute thread priority, and to
 106  * do profiling
 107  */
 108 void
 109 hertz_tick(
 110         boolean_t                       usermode,       /* executing user code */
 111         natural_t                       pc)
 112 {
 113         thread_act_t            thr_act;
 114         register int            my_cpu;
 115         register thread_t       thread = current_thread();
 116         int                                     state;
 117 #if             MACH_PROF
 118 #ifdef  __MACHO__
 119 #define ETEXT                   etext
 120         extern long                     etext;
 121 #else
 122 #define ETEXT                   &etext
 123         extern char                     etext;
 124 #endif
 125         boolean_t                       inkernel;
 126 #endif  /* MACH_PROF */
 127 #if GPROF
 128         struct profile_vars     *pv;
 129         prof_uptrint_t          s;
 130 #endif
 131
 132 #ifdef  lint
 133         pc++;
 134 #endif  /* lint */
 135
 136         mp_disable_preemption();
 137         my_cpu = cpu_number();
 138
 139         /*
 140          *      The system startup sequence initializes the clock
 141          *      before kicking off threads.   So it's possible,
 142          *      especially when debugging, to wind up here with
 143          *      no thread to bill against.  So ignore the tick.
 144          */
 145         if (thread == THREAD_NULL) {
 146                 mp_enable_preemption();
 147                 return;
 148         }
 149
 150 #if             MACH_PROF
 151         inkernel = !usermode && (pc < (unsigned int)ETEXT);
 152 #endif  /* MACH_PROF */
 153
 154         /*
 155          * Hertz processing performed by all processors
 156          * includes statistics gathering, state tracking,
 157          * and quantum updating.
 158          */
 159         counter(c_clock_ticks++);
 160
 161 #if     GPROF
 162         pv = PROFILE_VARS(my_cpu);
 163 #endif
 164
 165         if (usermode) {
 166                 TICKBUMP(&thread->user_timer);
 167 #if 0
 168                 if (thread->priority < BASEPRI_DEFAULT)
 169                         state = CPU_STATE_NICE;
 170                 else
 171 #endif
 172                         state = CPU_STATE_USER;
 173 #if GPROF
 174                         if (pv->active)
 175                             PROF_CNT_INC(pv->stats.user_ticks);
 176 #endif
 177         }
 178         else {
 179                 switch(processor_ptr[my_cpu]->state) {
 180
 181                 case PROCESSOR_IDLE:
 182                         TICKBUMP(&thread->system_timer);
 183                         state = CPU_STATE_IDLE;
 184                         break;
 185
 186                 default:
 187                         TICKBUMP(&thread->system_timer);
 188                         state = CPU_STATE_SYSTEM;
 189                         break;
 190                 }
 191 #if GPROF
 192                 if (pv->active) {
 193                         if (state == CPU_STATE_SYSTEM)
 194                                 PROF_CNT_INC(pv->stats.kernel_ticks);
 195                         else
 196                                 PROF_CNT_INC(pv->stats.idle_ticks);
 197
 198                         if ((prof_uptrint_t)pc < _profile_vars.profil_info.lowpc)
 199                                 PROF_CNT_INC(pv->stats.too_low);
 200                         else {
 201                                 s = (prof_uptrint_t)pc - _profile_vars.profil_info.lowpc;
 202                                 if (s < pv->profil_info.text_len) {
 203                                         LHISTCOUNTER *ptr = (LHISTCOUNTER *) pv->profil_buf;
 204                                         LPROF_CNT_INC(ptr[s / HISTFRACTION]);
 205                                 }
 206                                 else
 207                                         PROF_CNT_INC(pv->stats.too_high);
 208                         }
 209                 }
 210 #endif
 211         }
 212
 213         machine_slot[my_cpu].cpu_ticks[state]++;
 214         thread_quantum_update(my_cpu, thread, 1, state);
 215
 216         /*
 217          * Hertz processing performed by the master-cpu
 218          * exclusively.
 219          */
 220         if (my_cpu == master_cpu) {
 221 #ifdef MACH_BSD
 222                 {
 223                         extern void     bsd_hardclock(
 224                                                                 boolean_t       usermode,
 225                                                                 natural_t       pc,
 226                                                                 int                     ticks);
 227
 228                         bsd_hardclock(usermode, pc, 1);
 229                 }
 230 #endif /* MACH_BSD */
 231         }
 232
 233 #if     MACH_PROF
 234         thr_act = thread->top_act;
 235         if (thr_act->act_profiled) {
 236                 if (inkernel && thr_act->map != kernel_map) {
 237                         /*
 238                          * Non-kernel thread running in kernel
 239                          * Register user pc (mach_msg, vm_allocate ...)
 240                          */
 241                         if (profile_kernel_services)
 242                                 profile(user_pc(thr_act), thr_act->profil_buffer);
 243                 }
 244                 else
 245                         /*
 246                          * User thread and user mode or
 247                          * user (server) thread in kernel-loaded server or
 248                          * kernel thread and kernel mode
 249                          * register interrupted pc
 250                          */
 251                         profile(pc, thr_act->profil_buffer);
 252         }
 253         if (kernel_task->task_profiled) {
 254                 if (inkernel && thr_act->map != kernel_map)
 255                         /*
 256                          * User thread not profiled in kernel mode,
 257                          * kernel task profiled, register kernel pc
 258                          * for kernel task
 259                          */
 260                         profile(pc, kernel_task->profil_buffer);
 261         }
 262 #endif  /* MACH_PROF */
 263         mp_enable_preemption();
 264 }