osfmk/kern/etimer.c

   1 /*
   2  * Copyright (c) 2000-2005 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  * @APPLE_FREE_COPYRIGHT@
  33  */
  34 /*
  35  *      File:           etimer.c
  36  *      Purpose:        Routines for handling the machine independent
  37  *                              event timer.
  38  */
  39
  40 #include <mach/mach_types.h>
  41
  42 #include <kern/clock.h>
  43 #include <kern/thread.h>
  44 #include <kern/processor.h>
  45 #include <kern/macro_help.h>
  46 #include <kern/spl.h>
  47 #include <kern/etimer.h>
  48 #include <kern/pms.h>
  49
  50 #include <machine/commpage.h>
  51 #include <machine/machine_routines.h>
  52
  53 #include <sys/kdebug.h>
  54
  55 #ifdef __ppc__
  56 #include <ppc/exception.h>
  57 #else
  58 #include <i386/cpu_data.h>
  59 #endif
  60
  61 #include <sys/kdebug.h>
  62
  63
  64 /* XXX from <arch>/rtclock.c */
  65 uint32_t                        rtclock_tick_interval;
  66 clock_timer_func_t              rtclock_timer_expire;
  67
  68 #ifdef __ppc__
  69 # define PER_PROC_INFO          struct per_proc_info
  70 # define GET_PER_PROC_INFO()    getPerProc()
  71 #else
  72 # define PER_PROC_INFO          cpu_data_t
  73 # define GET_PER_PROC_INFO()    current_cpu_datap()
  74 #endif
  75
  76 /*
  77  *      Event timer interrupt.
  78  *
  79  * XXX a drawback of this implementation is that events serviced earlier must not set deadlines
  80  *     that occur before the entire chain completes.
  81  *
  82  * XXX a better implementation would use a set of generic callouts and iterate over them
  83  */
  84 void etimer_intr(int inuser, uint64_t iaddr) {
  85
  86         uint64_t                abstime;
  87         rtclock_timer_t         *mytimer;
  88         PER_PROC_INFO           *pp;
  89
  90         pp = GET_PER_PROC_INFO();
  91
  92         mytimer = &pp->rtclock_timer;                           /* Point to the event timer */
  93
  94         abstime = mach_absolute_time();                         /* Get the time now */
  95
  96         /* is it time for power management state change? */
  97         if (pp->pms.pmsPop <= abstime) {
  98
  99                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 3) | DBG_FUNC_START, 0, 0, 0, 0, 0);
 100                 pmsStep(1);                                     /* Yes, advance step */
 101                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 3) | DBG_FUNC_END, 0, 0, 0, 0, 0);
 102
 103                 abstime = mach_absolute_time();                 /* Get the time again since we ran a bit */
 104         }
 105
 106         /* have we passed the rtclock pop time? */
 107         if (pp->rtclock_intr_deadline <= abstime) {
 108
 109                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 4) | DBG_FUNC_START, (int)rtclock_tick_interval, 0, 0, 0, 0);
 110
 111                 clock_deadline_for_periodic_event(rtclock_tick_interval,
 112                     abstime,
 113                     &pp->rtclock_intr_deadline);
 114
 115                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 4) | DBG_FUNC_END, 0, 0, 0, 0, 0);
 116 #if STAT_TIME
 117                 hertz_tick(NSEC_PER_HZ, inuser, iaddr);         /* Accumulate hertz */
 118 #else
 119                 hertz_tick(inuser, iaddr);                      /* Accumulate hertz */
 120 #endif
 121
 122                 abstime = mach_absolute_time();                 /* Refresh the current time since we went away */
 123         }
 124
 125         /* has a pending clock timer expired? */
 126         if (mytimer->deadline <= abstime) {                     /* Have we expired the deadline? */
 127                 mytimer->has_expired = TRUE;                    /* Remember that we popped */
 128                 mytimer->deadline = EndOfAllTime;               /* Set timer request to the end of all time in case we have no more events */
 129                 (*rtclock_timer_expire)(abstime);               /* Process pop */
 130                 mytimer->has_expired = FALSE;
 131         }
 132
 133         /* schedule our next deadline */
 134         pp->rtcPop = EndOfAllTime;                              /* any real deadline will be earlier */
 135         etimer_resync_deadlines();
 136 }
 137
 138 /*
 139  * Set the clock deadline; called by the thread scheduler.
 140  */
 141 void etimer_set_deadline(uint64_t deadline)
 142 {
 143         rtclock_timer_t         *mytimer;
 144         spl_t                   s;
 145         PER_PROC_INFO           *pp;
 146
 147         s = splclock();                                 /* no interruptions */
 148         pp = GET_PER_PROC_INFO();
 149
 150         mytimer = &pp->rtclock_timer;                   /* Point to the timer itself */
 151         mytimer->deadline = deadline;                   /* Set the new expiration time */
 152
 153         etimer_resync_deadlines();
 154
 155         splx(s);
 156 }
 157
 158 /*
 159  * Re-evaluate the outstanding deadlines and select the most proximate.
 160  *
 161  * Should be called at splclock.
 162  */
 163 void
 164 etimer_resync_deadlines(void)
 165 {
 166         uint64_t                deadline;
 167         rtclock_timer_t         *mytimer;
 168         spl_t                   s = splclock();         /* No interruptions please */
 169         PER_PROC_INFO           *pp;
 170
 171         pp = GET_PER_PROC_INFO();
 172
 173         deadline = 0;
 174
 175         /* next rtclock interrupt? */
 176         if (pp->rtclock_intr_deadline > 0)
 177                 deadline = pp->rtclock_intr_deadline;
 178
 179         /* if we have a clock timer set sooner, pop on that */
 180         mytimer = &pp->rtclock_timer;                   /* Point to the timer itself */
 181         if ((!mytimer->has_expired) && (mytimer->deadline > 0) && (mytimer->deadline < deadline))
 182                 deadline = mytimer->deadline;
 183
 184         /* if we have a power management event coming up, how about that? */
 185         if ((pp->pms.pmsPop > 0) && (pp->pms.pmsPop < deadline))
 186                 deadline = pp->pms.pmsPop;
 187
 188 #ifdef __ppc__
 189 #endif
 190
 191         if ((deadline > 0) && (deadline < pp->rtcPop)) {
 192                 int     decr;
 193
 194                 pp->rtcPop = deadline;
 195                 decr = setPop(deadline);
 196
 197                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 1) | DBG_FUNC_NONE, decr, 2, 0, 0, 0);
 198         }
 199         splx(s);
 200 }