osfmk/kern/etimer.c

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * @OSF_COPYRIGHT@
  32  */
  33 /*
  34  * @APPLE_FREE_COPYRIGHT@
  35  */
  36 /*
  37  *      File:           etimer.c
  38  *      Purpose:        Routines for handling the machine independent
  39  *                              event timer.
  40  */
  41
  42 #include <mach/mach_types.h>
  43
  44 #include <kern/clock.h>
  45 #include <kern/thread.h>
  46 #include <kern/processor.h>
  47 #include <kern/macro_help.h>
  48 #include <kern/spl.h>
  49 #include <kern/etimer.h>
  50 #include <kern/pms.h>
  51
  52 #include <machine/commpage.h>
  53 #include <machine/machine_routines.h>
  54
  55 #include <sys/kdebug.h>
  56
  57 #ifdef __ppc__
  58 #include <ppc/exception.h>
  59 #else
  60 #include <i386/cpu_data.h>
  61 #endif
  62
  63 #include <sys/kdebug.h>
  64
  65
  66 /* XXX from <arch>/rtclock.c */
  67 uint32_t                        rtclock_tick_interval;
  68 clock_timer_func_t              rtclock_timer_expire;
  69
  70 #ifdef __ppc__
  71 # define PER_PROC_INFO          struct per_proc_info
  72 # define GET_PER_PROC_INFO()    getPerProc()
  73 #else
  74 # define PER_PROC_INFO          cpu_data_t
  75 # define GET_PER_PROC_INFO()    current_cpu_datap()
  76 #endif
  77
  78 /*
  79  *      Event timer interrupt.
  80  *
  81  * XXX a drawback of this implementation is that events serviced earlier must not set deadlines
  82  *     that occur before the entire chain completes.
  83  *
  84  * XXX a better implementation would use a set of generic callouts and iterate over them
  85  */
  86 void etimer_intr(int inuser, uint64_t iaddr) {
  87
  88         uint64_t                abstime;
  89         rtclock_timer_t         *mytimer;
  90         PER_PROC_INFO           *pp;
  91
  92         pp = GET_PER_PROC_INFO();
  93
  94         mytimer = &pp->rtclock_timer;                           /* Point to the event timer */
  95
  96         abstime = mach_absolute_time();                         /* Get the time now */
  97
  98         /* is it time for power management state change? */
  99         if (pp->pms.pmsPop <= abstime) {
 100
 101                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 3) | DBG_FUNC_START, 0, 0, 0, 0, 0);
 102                 pmsStep(1);                                     /* Yes, advance step */
 103                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 3) | DBG_FUNC_END, 0, 0, 0, 0, 0);
 104
 105                 abstime = mach_absolute_time();                 /* Get the time again since we ran a bit */
 106         }
 107
 108         /* have we passed the rtclock pop time? */
 109         if (pp->rtclock_intr_deadline <= abstime) {
 110
 111                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 4) | DBG_FUNC_START, (int)rtclock_tick_interval, 0, 0, 0, 0);
 112
 113                 clock_deadline_for_periodic_event(rtclock_tick_interval,
 114                     abstime,
 115                     &pp->rtclock_intr_deadline);
 116
 117                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 4) | DBG_FUNC_END, 0, 0, 0, 0, 0);
 118 #if STAT_TIME
 119                 hertz_tick(NSEC_PER_HZ, inuser, iaddr);         /* Accumulate hertz */
 120 #else
 121                 hertz_tick(inuser, iaddr);                      /* Accumulate hertz */
 122 #endif
 123
 124                 abstime = mach_absolute_time();                 /* Refresh the current time since we went away */
 125         }
 126
 127         /* has a pending clock timer expired? */
 128         if (mytimer->deadline <= abstime) {                     /* Have we expired the deadline? */
 129                 mytimer->has_expired = TRUE;                    /* Remember that we popped */
 130                 mytimer->deadline = EndOfAllTime;               /* Set timer request to the end of all time in case we have no more events */
 131                 (*rtclock_timer_expire)(abstime);               /* Process pop */
 132                 mytimer->has_expired = FALSE;
 133         }
 134
 135         /* schedule our next deadline */
 136         pp->rtcPop = EndOfAllTime;                              /* any real deadline will be earlier */
 137         etimer_resync_deadlines();
 138 }
 139
 140 /*
 141  * Set the clock deadline; called by the thread scheduler.
 142  */
 143 void etimer_set_deadline(uint64_t deadline)
 144 {
 145         rtclock_timer_t         *mytimer;
 146         spl_t                   s;
 147         PER_PROC_INFO           *pp;
 148
 149         s = splclock();                                 /* no interruptions */
 150         pp = GET_PER_PROC_INFO();
 151
 152         mytimer = &pp->rtclock_timer;                   /* Point to the timer itself */
 153         mytimer->deadline = deadline;                   /* Set the new expiration time */
 154
 155         etimer_resync_deadlines();
 156
 157         splx(s);
 158 }
 159
 160 /*
 161  * Re-evaluate the outstanding deadlines and select the most proximate.
 162  *
 163  * Should be called at splclock.
 164  */
 165 void
 166 etimer_resync_deadlines(void)
 167 {
 168         uint64_t                deadline;
 169         rtclock_timer_t         *mytimer;
 170         spl_t                   s = splclock();         /* No interruptions please */
 171         PER_PROC_INFO           *pp;
 172
 173         pp = GET_PER_PROC_INFO();
 174
 175         deadline = 0;
 176
 177         /* next rtclock interrupt? */
 178         if (pp->rtclock_intr_deadline > 0)
 179                 deadline = pp->rtclock_intr_deadline;
 180
 181         /* if we have a clock timer set sooner, pop on that */
 182         mytimer = &pp->rtclock_timer;                   /* Point to the timer itself */
 183         if ((!mytimer->has_expired) && (mytimer->deadline > 0) && (mytimer->deadline < deadline))
 184                 deadline = mytimer->deadline;
 185
 186         /* if we have a power management event coming up, how about that? */
 187         if ((pp->pms.pmsPop > 0) && (pp->pms.pmsPop < deadline))
 188                 deadline = pp->pms.pmsPop;
 189
 190 #ifdef __ppc__
 191 #endif
 192
 193         if ((deadline > 0) && (deadline < pp->rtcPop)) {
 194                 int     decr;
 195
 196                 pp->rtcPop = deadline;
 197                 decr = setPop(deadline);
 198
 199                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 1) | DBG_FUNC_NONE, decr, 2, 0, 0, 0);
 200         }
 201         splx(s);
 202 }