xnu-792.6.56.tar.gz

[apple/xnu.git] / osfmk / kern / timer.c

diff --git a/osfmk/kern/timer.c b/osfmk/kern/timer.c
index 996bc6fe6d2419b152a1e26469b6e8a38bcc4d0e..845314fbf7c32b97cbbdb7756d2b074d60d66d63 100644 (file)
--- a/osfmk/kern/timer.c
+++ b/osfmk/kern/timer.c
@@ -3,19 +3,20 @@
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
  *
  * @APPLE_LICENSE_HEADER_START@
  * 

- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.

  * 
  * 

- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER

  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.

  * 
  * @APPLE_LICENSE_HEADER_END@
  */
  * 
  * @APPLE_LICENSE_HEADER_END@
  */


@@ -50,542 +51,129 @@
 /* 
  */
 
 /* 
  */
 

-#include <cpus.h>

 #include <stat_time.h>
 #include <stat_time.h>

+#include <machine_timer_routines.h>

 
 #include <mach/kern_return.h>
 #include <mach/port.h>
 #include <kern/queue.h>
 
 #include <mach/kern_return.h>
 #include <mach/port.h>
 #include <kern/queue.h>

+#include <kern/processor.h>

 #include <kern/thread.h>
 #include <kern/sched_prim.h>
 #include <kern/thread.h>
 #include <kern/sched_prim.h>

-#include <mach/time_value.h>

 #include <kern/timer.h>
 #include <kern/timer.h>

-#include <kern/cpu_number.h>
-
-#include <kern/assert.h>
-#include <kern/macro_help.h>
-
-timer_t                current_timer[NCPUS];
-timer_data_t   kernel_timer[NCPUS];
-
-/* Forwards */
-void           timer_grab(
-                       timer_t         timer,
-                       timer_save_t    save);
-
-void           db_timer_grab(
-                       timer_t         timer,
-                       timer_save_t    save);
-
-void           db_thread_read_times(
-                       thread_t        thread,
-                       time_value_t    *user_time_p,
-                       time_value_t    *system_time_p);

 
 /*
 
 /*

- *     init_timers initializes all non-thread timers and puts the
- *     service routine on the callout queue.  All timers must be
- *     serviced by the callout routine once an hour.
- */
-void
-init_timers(void)
-{
-       register int    i;
-       register timer_t        this_timer;
-
-       /*
-        *      Initialize all the kernel timers and start the one
-        *      for this cpu (master) slaves start theirs later.
-        */
-       this_timer = &kernel_timer[0];
-       for ( i=0 ; i<NCPUS ; i++, this_timer++) {
-               timer_init(this_timer);
-               current_timer[i] = (timer_t) 0;
-       }
-
-       mp_disable_preemption();
-       start_timer(&kernel_timer[cpu_number()]);
-       mp_enable_preemption();
-}
-
-/*
- *     timer_init initializes a single timer.
+ *     timer_init initializes a timer.

  */
 void
 timer_init(
  */
 void
 timer_init(

-       register timer_t        this_timer)
+       timer_t         timer)

 {
 {

-       this_timer->low_bits = 0;
-       this_timer->high_bits = 0;
-       this_timer->tstamp = 0;
-       this_timer->high_bits_check = 0;
-}
-
-#if    STAT_TIME
-#else  /* STAT_TIME */
-
-#ifdef MACHINE_TIMER_ROUTINES
-
-/*
- *     Machine-dependent code implements the timer routines.
- */
-
-#else  /* MACHINE_TIMER_ROUTINES */
-
-/*
- *     start_timer starts the given timer for this cpu. It is called
- *     exactly once for each cpu during the boot sequence.
- */
-void
-start_timer(
-       register timer_t        timer)
-{
-       timer->tstamp = get_timestamp();
-       mp_disable_preemption();
-       current_timer[cpu_number()] = timer;
-       mp_enable_preemption();
-}
-
-/*
- *     time_trap_uentry does trap entry timing.  Caller must lock out
- *     interrupts and take a timestamp.  ts is a timestamp taken after
- *     interrupts were locked out. Must only be called if trap was
- *     from user mode.
- */
-void
-time_trap_uentry(
-       unsigned        ts)
-{
-       int     elapsed;
-       int     mycpu;
-       timer_t mytimer;
-
-       mp_disable_preemption();
-
-       /*
-        *      Calculate elapsed time.
-        */
-       mycpu = cpu_number();
-       mytimer = current_timer[mycpu];
-       elapsed = ts - mytimer->tstamp;
-#ifdef TIMER_MAX
-       if (elapsed < 0) elapsed += TIMER_MAX;
-#endif /* TIMER_MAX */
-
-       /*
-        *      Update current timer.
-        */
-       mytimer->low_bits += elapsed;
-       mytimer->tstamp = 0;
-
-       if (mytimer->low_bits & TIMER_LOW_FULL) {
-               timer_normalize(mytimer);
-       }
-
-       /*
-        *      Record new timer.
-        */
-       mytimer = &(current_thread()->system_timer);
-       current_timer[mycpu] = mytimer;
-       mytimer->tstamp = ts;
-
-       mp_enable_preemption();
-}
-
-/*
- *     time_trap_uexit does trap exit timing.  Caller must lock out
- *     interrupts and take a timestamp.  ts is a timestamp taken after
- *     interrupts were locked out.  Must only be called if returning to
- *     user mode.
- */
-void
-time_trap_uexit(
-       unsigned        ts)
-{
-       int     elapsed;
-       int     mycpu;
-       timer_t mytimer;
-
-       mp_disable_preemption();
-
-       /*
-        *      Calculate elapsed time.
-        */
-       mycpu = cpu_number();
-       mytimer = current_timer[mycpu];
-       elapsed = ts - mytimer->tstamp;
-#ifdef TIMER_MAX
-       if (elapsed < 0) elapsed += TIMER_MAX;
-#endif /* TIMER_MAX */
-
-       /*
-        *      Update current timer.
-        */
-       mytimer->low_bits += elapsed;
-       mytimer->tstamp = 0;
-
-       if (mytimer->low_bits & TIMER_LOW_FULL) {
-               timer_normalize(mytimer);       /* SYSTEMMODE */
-       }
-
-       mytimer = &(current_thread()->user_timer);
-
-       /*
-        *      Record new timer.
-        */
-       current_timer[mycpu] = mytimer;
-       mytimer->tstamp = ts;
-
-       mp_enable_preemption();
+       timer->low_bits = 0;
+       timer->high_bits = 0;
+       timer->high_bits_check = 0;
+#if    !STAT_TIME
+       timer->tstamp = 0;
+#endif /* STAT_TIME */

 }
 
 /*
 }
 
 /*

- *     time_int_entry does interrupt entry timing.  Caller must lock out
- *     interrupts and take a timestamp. ts is a timestamp taken after
- *     interrupts were locked out.  new_timer is the new timer to
- *     switch to.  This routine returns the currently running timer,
- *     which MUST be pushed onto the stack by the caller, or otherwise
- *     saved for time_int_exit.
+ *     Calculate the difference between a timer
+ *     and saved value, and update the saved value.

  */
  */

-timer_t
-time_int_entry(
-       unsigned        ts,
-       timer_t         new_timer)
+uint64_t
+timer_delta(
+       timer_t         timer,
+       uint64_t        *save)

 {
 {

-       int     elapsed;
-       int     mycpu;
-       timer_t mytimer;
-
-       mp_disable_preemption();
-
-       /*
-        *      Calculate elapsed time.
-        */
-       mycpu = cpu_number();
-       mytimer = current_timer[mycpu];
-
-       elapsed = ts - mytimer->tstamp;
-#ifdef TIMER_MAX
-       if (elapsed < 0) elapsed += TIMER_MAX;
-#endif /* TIMER_MAX */
+       uint64_t        new, old = *save;

 
 

-       /*
-        *      Update current timer.
-        */
-       mytimer->low_bits += elapsed;
-       mytimer->tstamp = 0;
-
-       /*
-        *      Switch to new timer, and save old one on stack.
-        */
-       new_timer->tstamp = ts;
-       current_timer[mycpu] = new_timer;
+       *save = new = timer_grab(timer);

 
 

-       mp_enable_preemption();
-
-       return(mytimer);
+       return (new - old);

 }
 
 }
 

-/*
- *     time_int_exit does interrupt exit timing.  Caller must lock out
- *     interrupts and take a timestamp.  ts is a timestamp taken after
- *     interrupts were locked out.  old_timer is the timer value pushed
- *     onto the stack or otherwise saved after time_int_entry returned
- *     it.
- */
-void
-time_int_exit(
-       unsigned        ts,
-       timer_t         old_timer)
-{
-       int     elapsed;
-       int     mycpu;
-       timer_t mytimer;
-
-       mp_disable_preemption();
-
-       /*
-        *      Calculate elapsed time.
-        */
-       mycpu = cpu_number();
-       mytimer = current_timer[mycpu];
-       elapsed = ts - mytimer->tstamp;
-#ifdef TIMER_MAX
-       if (elapsed < 0) elapsed += TIMER_MAX;
-#endif /* TIMER_MAX */
-
-       /*
-        *      Update current timer.
-        */
-       mytimer->low_bits += elapsed;
-       mytimer->tstamp = 0;
-
-       /*
-        *      If normalization requested, do it.
-        */
-       if (mytimer->low_bits & TIMER_LOW_FULL) {
-               timer_normalize(mytimer);
-       }
-       if (old_timer->low_bits & TIMER_LOW_FULL) {
-               timer_normalize(old_timer);
-       }
-
-       /*
-        *      Start timer that was running before interrupt.
-        */
-       old_timer->tstamp = ts;
-       current_timer[mycpu] = old_timer;
-
-       mp_enable_preemption();
-}
+#if    !STAT_TIME

 
 /*
 
 /*

- *     timer_switch switches to a new timer.  The machine
- *     dependent routine/macro get_timestamp must return a timestamp.
- *     Caller must lock out interrupts.
+ *     Update the current timer (if any)
+ *     and start the new timer, which
+ *     could be either the same or NULL.
+ *
+ *     Called with interrupts disabled.

  */
 void
 timer_switch(
  */
 void
 timer_switch(

-       timer_t new_timer)
+       uint32_t                tstamp,
+       timer_t                 new_timer)

 {
 {

-       int             elapsed;
-       int             mycpu;
-       timer_t         mytimer;
-       unsigned        ts;
-
-       mp_disable_preemption();
-
-       /*
-        *      Calculate elapsed time.
-        */
-       mycpu = cpu_number();
-       mytimer = current_timer[mycpu];
-       ts = get_timestamp();
-       elapsed = ts - mytimer->tstamp;
-#ifdef TIMER_MAX
-       if (elapsed < 0) elapsed += TIMER_MAX;
-#endif /* TIMER_MAX */
+       processor_t             processor = current_processor();
+       timer_t                 timer;
+       uint32_t                old_low, low;

 
        /*
         *      Update current timer.
         */
 
        /*
         *      Update current timer.
         */

-       mytimer->low_bits += elapsed;
-       mytimer->tstamp = 0;
-
-       /*
-        *      Normalization check
-        */
-       if (mytimer->low_bits & TIMER_LOW_FULL) {
-               timer_normalize(mytimer);
+       timer = PROCESSOR_DATA(processor, current_timer);
+       if (timer != NULL) {
+               old_low = timer->low_bits;
+               low = old_low + tstamp - timer->tstamp;
+               if (low < old_low)
+                       timer_update(timer, timer->high_bits + 1, low);
+               else
+                       timer->low_bits = low;

        }
 
        /*
        }
 
        /*

-        *      Record new timer.
+        *      Start new timer.

         */
         */

-       current_timer[mycpu] = new_timer;
-       new_timer->tstamp = ts;
-
-       mp_enable_preemption();
+       PROCESSOR_DATA(processor, current_timer) = new_timer;
+       if (new_timer != NULL)
+               new_timer->tstamp = tstamp;

 }
 
 }
 

-#endif /* MACHINE_TIMER_ROUTINES */
-#endif /* STAT_TIME */
+#if    MACHINE_TIMER_ROUTINES

 
 /*
 
 /*

- *     timer_normalize normalizes the value of a timer.  It is
- *     called only rarely, to make sure low_bits never overflows.
+ *     Machine-dependent code implements the timer event routine.

  */
 
  */
 

-void
-timer_normalize(
-       register timer_t        timer)
-{
-       unsigned int    high_increment;
-
-       /*
-        *      Calculate high_increment, then write high check field first
-        *      followed by low and high.  timer_grab() reads these fields in
-        *      reverse order so if high and high check match, we know
-        *      that the values read are ok.
-        */
-
-       high_increment = timer->low_bits/TIMER_HIGH_UNIT;
-       timer->high_bits_check += high_increment;
-       timer->low_bits %= TIMER_HIGH_UNIT;
-       timer->high_bits += high_increment;
-}
+#else  /* MACHINE_TIMER_ROUTINES */

 
 /*
 
 /*

- *     timer_grab() retrieves the value of a timer.
+ *     Update the current timer and start
+ *     the new timer.  Requires a current
+ *     and new timer.

  *
  *

- *     Critical scheduling code uses TIMER_DELTA macro in timer.h
- *     (called from thread_timer_delta in sched.h).
- *    
- *      Keep coherent with db_time_grab below.
+ *     Called with interrupts disabled.

  */
  */

-

 void
 void

-timer_grab(
-       timer_t         timer,
-       timer_save_t    save)
+timer_event(
+       uint32_t                tstamp,
+       timer_t                 new_timer)

 {
 {

-#if MACH_ASSERT
-       unsigned int passes=0;
-#endif
-       do {
-               (save)->high = (timer)->high_bits;
-               (save)->low = (timer)->low_bits;
+       processor_t             processor = current_processor();
+       timer_t                 timer;
+       uint32_t                old_low, low;
+

        /*
        /*

-        *      If the timer was normalized while we were doing this,
-        *      the high_bits value read above and the high_bits check
-        *      value will not match because high_bits_check is the first
-        *      field touched by the normalization procedure, and
-        *      high_bits is the last.
-        *
-        *      Additions to timer only touch low bits and
-        *      are therefore atomic with respect to this.
+        *      Update current timer.

         */
         */

-#if MACH_ASSERT
-               passes++;
-               assert(passes < 10000);
-#endif         
-       } while ( (save)->high != (timer)->high_bits_check);
-}
+       timer = PROCESSOR_DATA(processor, current_timer);
+       old_low = timer->low_bits;
+       low = old_low + tstamp - timer->tstamp;
+       if (low < old_low)
+               timer_update(timer, timer->high_bits + 1, low);
+       else
+               timer->low_bits = low;

 
 

-/*
- *
- *     Db_timer_grab(): used by db_thread_read_times. An nonblocking
- *      version of db_thread_get_times. Keep coherent with timer_grab
- *      above.
- *
- */
-void
-db_timer_grab(
-       timer_t         timer,
-       timer_save_t    save)
-{
-  /* Don't worry about coherency */
-
-  (save)->high = (timer)->high_bits;
-  (save)->low = (timer)->low_bits;
-}
-
-
-/*
- *     timer_read reads the value of a timer into a time_value_t.  If the
- *     timer was modified during the read, retry.  The value returned
- *     is accurate to the last update; time accumulated by a running
- *     timer since its last timestamp is not included.
- */
-
-void
-timer_read(
-       timer_t timer,
-       register time_value_t *tv)
-{
-       timer_save_data_t       temp;
-
-       timer_grab(timer,&temp);

        /*
        /*

-        *      Normalize the result
+        *      Start new timer.

         */
         */

-#ifdef TIMER_ADJUST
-       TIMER_ADJUST(&temp);
-#endif /* TIMER_ADJUST */
-       tv->seconds = temp.high + temp.low/1000000;
-       tv->microseconds = temp.low%1000000;
-}
-
-/*
- *     thread_read_times reads the user and system times from a thread.
- *     Time accumulated since last timestamp is not included.  Should
- *     be called at splsched() to avoid having user and system times
- *     be out of step.  Doesn't care if caller locked thread.
- *
- *      Needs to be kept coherent with thread_read_times ahead.
- */
-void
-thread_read_times(
-       thread_t        thread,
-       time_value_t    *user_time_p,
-       time_value_t    *system_time_p)
-{
-       timer_save_data_t       temp;
-       register timer_t        timer;
-
-       timer = &thread->user_timer;
-       timer_grab(timer, &temp);
-
-#ifdef TIMER_ADJUST
-       TIMER_ADJUST(&temp);
-#endif /* TIMER_ADJUST */
-       user_time_p->seconds = temp.high + temp.low/1000000;
-       user_time_p->microseconds = temp.low % 1000000;
-
-       timer = &thread->system_timer;
-       timer_grab(timer, &temp);
-
-#ifdef TIMER_ADJUST
-       TIMER_ADJUST(&temp);
-#endif /* TIMER_ADJUST */
-       system_time_p->seconds = temp.high + temp.low/1000000;
-       system_time_p->microseconds = temp.low % 1000000;
-}
-
-/*
- *      Db_thread_read_times: A version of thread_read_times that
- *      can be called by the debugger. This version does not call
- *      timer_grab, which can block. Please keep it up to date with
- *      thread_read_times above.
- *
- */
-void
-db_thread_read_times(
-       thread_t        thread,
-       time_value_t    *user_time_p,
-       time_value_t    *system_time_p)
-{
-       timer_save_data_t       temp;
-       register timer_t        timer;
-
-       timer = &thread->user_timer;
-       db_timer_grab(timer, &temp);
-
-#ifdef TIMER_ADJUST
-       TIMER_ADJUST(&temp);
-#endif /* TIMER_ADJUST */
-       user_time_p->seconds = temp.high + temp.low/1000000;
-       user_time_p->microseconds = temp.low % 1000000;
-
-       timer = &thread->system_timer;
-       timer_grab(timer, &temp);
-
-#ifdef TIMER_ADJUST
-       TIMER_ADJUST(&temp);
-#endif /* TIMER_ADJUST */
-       system_time_p->seconds = temp.high + temp.low/1000000;
-       system_time_p->microseconds = temp.low % 1000000;
+       PROCESSOR_DATA(processor, current_timer) = new_timer;
+       new_timer->tstamp = tstamp;

 }
 
 }
 

-/*
- *     timer_delta takes the difference of a saved timer value
- *     and the current one, and updates the saved value to current.
- *     The difference is returned as a function value.  See
- *     TIMER_DELTA macro (timer.h) for optimization to this.
- */
-
-unsigned
-timer_delta(
-       register timer_t timer,
-       timer_save_t    save)
-{
-       timer_save_data_t       new_save;
-       register unsigned       result;
+#endif /* MACHINE_TIMER_ROUTINES */

 
 

-       timer_grab(timer,&new_save);
-       result = (new_save.high - save->high) * TIMER_HIGH_UNIT +
-               new_save.low - save->low;
-       save->high = new_save.high;
-       save->low = new_save.low;
-       return(result);
-}
+#endif /* STAT_TIME */