osfmk/kern/mach_clock.c

   1 /*
   2  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  */
  58 /*
  59  *      File:   clock_prim.c
  60  *      Author: Avadis Tevanian, Jr.
  61  *      Date:   1986
  62  *
  63  *      Clock primitives.
  64  */
  65 #include <mach_prof.h>
  66 #include <gprof.h>
  67
  68 #include <mach/boolean.h>
  69 #include <mach/machine.h>
  70 #include <mach/time_value.h>
  71 #include <mach/vm_param.h>
  72 #include <mach/vm_prot.h>
  73 #include <kern/clock.h>
  74 #include <kern/counters.h>
  75 #include <kern/cpu_number.h>
  76 #include <kern/host.h>
  77 #include <kern/lock.h>
  78 #include <kern/mach_param.h>
  79 #include <kern/misc_protos.h>
  80 #include <kern/processor.h>
  81 #include <kern/profile.h>
  82 #include <kern/sched.h>
  83 #include <kern/sched_prim.h>
  84 #include <kern/spl.h>
  85 #include <kern/thread.h>
  86 #include <vm/vm_kern.h>                                 /* kernel_map */
  87
  88 #include <mach/clock_server.h>
  89 #include <mach/clock_priv_server.h>
  90 #include <mach/mach_host_server.h>
  91
  92 #include <profiling/profile-mk.h>
  93
  94 boolean_t       profile_kernel_services = TRUE; /* Indicates wether or not we
  95                                                                                          * account kernel services
  96
  97                                                                                          * samples for user task */
  98 #ifdef MACH_BSD
  99 extern void     bsd_hardclock(
 100                         boolean_t       usermode,
 101                         natural_t       pc,
 102                         int             numticks);
 103 #endif /* MACH_BSD */
 104
 105 /*
 106  * Hertz rate clock interrupt servicing. Primarily used to
 107  * update CPU statistics, recompute thread priority, and to
 108  * do profiling
 109  */
 110 void
 111 hertz_tick(
 112 #if     STAT_TIME
 113         natural_t               ticks,
 114 #endif  /* STAT_TIME */
 115         boolean_t               usermode,
 116         natural_t               pc)
 117 {
 118         processor_t             processor = current_processor();
 119         thread_t                thread = current_thread();
 120         int                             state;
 121 #if             MACH_PROF
 122 #ifdef  __MACHO__
 123 #define ETEXT           etext
 124         extern long             etext;
 125 #else
 126 #define ETEXT           &etext
 127         extern char             etext;
 128 #endif
 129         boolean_t               inkernel;
 130 #endif  /* MACH_PROF */
 131 #if GPROF
 132         struct profile_vars     *pv;
 133         prof_uptrint_t          s;
 134 #endif
 135
 136 #ifdef  lint
 137         pc++;
 138 #endif  /* lint */
 139
 140         /*
 141          *      The system startup sequence initializes the clock
 142          *      before kicking off threads.   So it's possible,
 143          *      especially when debugging, to wind up here with
 144          *      no thread to bill against.  So ignore the tick.
 145          */
 146         if (thread == THREAD_NULL)
 147                 return;
 148
 149 #if             MACH_PROF
 150         inkernel = !usermode && (pc < (unsigned int)ETEXT);
 151 #endif  /* MACH_PROF */
 152
 153         /*
 154          * Hertz processing performed by all processors
 155          * includes statistics gathering, state tracking,
 156          * and quantum updating.
 157          */
 158         counter(c_clock_ticks++);
 159
 160 #if     GPROF
 161         pv = PROFILE_VARS(cpu_number());
 162 #endif
 163
 164         if (usermode) {
 165                 TIMER_BUMP(&thread->user_timer, ticks);
 166                 if (thread->priority < BASEPRI_DEFAULT)
 167                         state = CPU_STATE_NICE;
 168                 else
 169                         state = CPU_STATE_USER;
 170 #if GPROF
 171                         if (pv->active)
 172                             PROF_CNT_INC(pv->stats.user_ticks);
 173 #endif
 174         }
 175         else {
 176                 TIMER_BUMP(&thread->system_timer, ticks);
 177
 178                 state = processor->state;
 179                 if (    state == PROCESSOR_IDLE                 ||
 180                                 state == PROCESSOR_DISPATCHING)
 181                         state = CPU_STATE_IDLE;
 182                 else
 183                 if (thread->options & TH_OPT_DELAYIDLE)
 184                         state = CPU_STATE_IDLE;
 185                 else
 186                         state = CPU_STATE_SYSTEM;
 187 #if GPROF
 188                 if (pv->active) {
 189                         if (state == CPU_STATE_SYSTEM)
 190                                 PROF_CNT_INC(pv->stats.kernel_ticks);
 191                         else
 192                                 PROF_CNT_INC(pv->stats.idle_ticks);
 193
 194                         if ((prof_uptrint_t)pc < _profile_vars.profil_info.lowpc)
 195                                 PROF_CNT_INC(pv->stats.too_low);
 196                         else {
 197                                 s = (prof_uptrint_t)pc - _profile_vars.profil_info.lowpc;
 198                                 if (s < pv->profil_info.text_len) {
 199                                         LHISTCOUNTER *ptr = (LHISTCOUNTER *) pv->profil_buf;
 200                                         LPROF_CNT_INC(ptr[s / HISTFRACTION]);
 201                                 }
 202                                 else
 203                                         PROF_CNT_INC(pv->stats.too_high);
 204                         }
 205                 }
 206 #endif
 207         }
 208
 209         PROCESSOR_DATA(processor, cpu_ticks[state]++);
 210
 211 #ifdef MACH_BSD
 212         /*XXX*/
 213         if (processor == master_processor) {
 214                 bsd_hardclock(usermode, pc, 1);
 215         }
 216         /*XXX*/
 217 #endif /* MACH_BSD */
 218
 219 #if     MACH_PROF
 220         if (thread->act_profiled) {
 221                 if (inkernel && thread->map != kernel_map) {
 222                         /*
 223                          * Non-kernel thread running in kernel
 224                          * Register user pc (mach_msg, vm_allocate ...)
 225                          */
 226                         if (profile_kernel_services)
 227                                 profile(user_pc(thread), thread->profil_buffer);
 228                 }
 229                 else
 230                         /*
 231                          * User thread and user mode or
 232                          * user (server) thread in kernel-loaded server or
 233                          * kernel thread and kernel mode
 234                          * register interrupted pc
 235                          */
 236                         profile(pc, thread->profil_buffer);
 237         }
 238         if (kernel_task->task_profiled) {
 239                 if (inkernel && thread->map != kernel_map)
 240                         /*
 241                          * User thread not profiled in kernel mode,
 242                          * kernel task profiled, register kernel pc
 243                          * for kernel task
 244                          */
 245                         profile(pc, kernel_task->profil_buffer);
 246         }
 247 #endif  /* MACH_PROF */
 248 }