xnu-6153.81.5.tar.gz

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

diff --git a/osfmk/kern/timer.c b/osfmk/kern/timer.c
index 3540b1ef7839e042ed8d32aaec02d0a26e297afa..4be4464cba479ba4f5c35f57e7751738ba4244e3 100644 (file)
--- a/osfmk/kern/timer.c
+++ b/osfmk/kern/timer.c
@@ -1,17 +1,20 @@
 /*
 /*

- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  *
  *

- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
- * 

  * 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
  * 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.
- * 
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *

  * 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,
  * 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,


@@ -19,576 +22,127 @@
  * 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.
  * 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_OSREFERENCE_LICENSE_HEADER_END@

  */
 /*
  * @OSF_COPYRIGHT@
  */
  */
 /*
  * @OSF_COPYRIGHT@
  */

-/* 
+/*

  * Mach Operating System
  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
  * All Rights Reserved.
  * Mach Operating System
  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
  * All Rights Reserved.

- * 
+ *

  * Permission to use, copy, modify and distribute this software and its
  * documentation is hereby granted, provided that both the copyright
  * notice and this permission notice appear in all copies of the
  * software, derivative works or modified versions, and any portions
  * thereof, and that both notices appear in supporting documentation.
  * Permission to use, copy, modify and distribute this software and its
  * documentation is hereby granted, provided that both the copyright
  * notice and this permission notice appear in all copies of the
  * software, derivative works or modified versions, and any portions
  * thereof, and that both notices appear in supporting documentation.

- * 
+ *

  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.

- * 
+ *

  * Carnegie Mellon requests users of this software to return to
  * Carnegie Mellon requests users of this software to return to

- * 
+ *

  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  *  School of Computer Science
  *  Carnegie Mellon University
  *  Pittsburgh PA 15213-3890
  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  *  School of Computer Science
  *  Carnegie Mellon University
  *  Pittsburgh PA 15213-3890

- * 
+ *

  * any improvements or extensions that they make and grant Carnegie Mellon
  * the rights to redistribute these changes.
  */
  * any improvements or extensions that they make and grant Carnegie Mellon
  * the rights to redistribute these changes.
  */

-/* 
- */
-
-#include <cpus.h>
-#include <stat_time.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.
- */
-void
-timer_init(
-       register timer_t        this_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();
-}
+#if CONFIG_EMBEDDED
+int precise_user_kernel_time = 0;
+#else
+int precise_user_kernel_time = 1;
+#endif

 
 

-/*
- *     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
 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();
-}
-
-/*
- *     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.
- */
-timer_t
-time_int_entry(
-       unsigned        ts,
-       timer_t         new_timer)
+timer_init(timer_t 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;
-
-       /*
-        *      Switch to new timer, and save old one on stack.
-        */
-       new_timer->tstamp = ts;
-       current_timer[mycpu] = new_timer;
-
-       mp_enable_preemption();
-
-       return(mytimer);
+       memset(timer, 0, sizeof(*timer));

 }
 
 }
 

-/*
- *     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)
+uint64_t
+timer_delta(timer_t timer, uint64_t *prev_in_cur_out)

 {
 {

-       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();
+       uint64_t old = *prev_in_cur_out;
+       uint64_t new = *prev_in_cur_out = timer_grab(timer);
+       return new - old;

 }
 
 }
 

-/*
- *     timer_switch switches to a new timer.  The machine
- *     dependent routine/macro get_timestamp must return a timestamp.
- *     Caller must lock out interrupts.
- */
-void
-timer_switch(
-       timer_t new_timer)
+static void
+timer_advance(timer_t timer, uint64_t delta)

 {
 {

-       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 */
-
-       /*
-        *      Update current timer.
-        */
-       mytimer->low_bits += elapsed;
-       mytimer->tstamp = 0;
-
-       /*
-        *      Normalization check
-        */
-       if (mytimer->low_bits & TIMER_LOW_FULL) {
-               timer_normalize(mytimer);
+#if defined(__LP64__)
+       timer->all_bits += delta;
+#else /* defined(__LP64__) */
+       extern void timer_advance_internal_32(timer_t timer, uint32_t high,
+           uint32_t low);
+       uint64_t low = delta + timer->low_bits;
+       if (low >> 32) {
+               timer_advance_internal_32(timer,
+                   (uint32_t)(timer->high_bits + (low >> 32)), (uint32_t)low);
+       } else {
+               timer->low_bits = (uint32_t)low;

        }
        }

-
-       /*
-        *      Record new timer.
-        */
-       current_timer[mycpu] = new_timer;
-       new_timer->tstamp = ts;
-
-       mp_enable_preemption();
-}
-
-#endif /* MACHINE_TIMER_ROUTINES */
-#endif /* STAT_TIME */
-
-/*
- *     timer_normalize normalizes the value of a timer.  It is
- *     called only rarely, to make sure low_bits never overflows.
- */
-
-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;
+#endif /* defined(__LP64__) */

 }
 
 }
 

-/*
- *     timer_grab() retrieves the value of a 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.
- */
-

 void
 void

-timer_grab(
-       timer_t         timer,
-       timer_save_t    save)
+timer_start(timer_t timer, uint64_t tstamp)

 {
 {

-#if MACH_ASSERT
-       unsigned int passes=0;
-#endif
-       do {
-               (save)->high = (timer)->high_bits;
-               (save)->low = (timer)->low_bits;
-       /*
-        *      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.
-        */
-#if MACH_ASSERT
-               passes++;
-               assert(passes < 10000);
-#endif         
-       } while ( (save)->high != (timer)->high_bits_check);
+       timer->tstamp = tstamp;

 }
 
 }
 

-/*
- *
- *     Db_timer_grab(): used by db_thread_read_times. An nonblocking
- *      version of db_thread_get_times. Keep coherent with timer_grab
- *      above.
- *
- */

 void
 void

-db_timer_grab(
-       timer_t         timer,
-       timer_save_t    save)
+timer_stop(timer_t timer, uint64_t tstamp)

 {
 {

-  /* Don't worry about coherency */
-
-  (save)->high = (timer)->high_bits;
-  (save)->low = (timer)->low_bits;
+       timer_advance(timer, tstamp - timer->tstamp);

 }
 
 }
 

-
-/*
- *     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
 void

-timer_read(
-       timer_t timer,
-       register time_value_t *tv)
+timer_update(timer_t timer, uint64_t tstamp)

 {
 {

-       timer_save_data_t       temp;
-
-       timer_grab(timer,&temp);
-       /*
-        *      Normalize the result
-        */
-#ifdef TIMER_ADJUST
-       TIMER_ADJUST(&temp);
-#endif /* TIMER_ADJUST */
-       tv->seconds = temp.high + temp.low/1000000;
-       tv->microseconds = temp.low%1000000;
+       timer_advance(timer, tstamp - timer->tstamp);
+       timer->tstamp = tstamp;

 }
 
 }
 

-/*
- *     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
 void

-thread_read_times(
-       thread_t        thread,
-       time_value_t    *user_time_p,
-       time_value_t    *system_time_p)
+timer_switch(timer_t timer, uint64_t tstamp, timer_t new_timer)

 {
 {

-       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;
+       timer_advance(timer, tstamp - timer->tstamp);
+       new_timer->tstamp = tstamp;

 }
 
 /*
 }
 
 /*

- *      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.
+ * Update the current processor's thread timer with `tstamp` and switch the
+ * processor's thread timer to `new_timer`.

  *
  *

+ * Called with interrupts disabled.

  */
 void
  */
 void

-db_thread_read_times(
-       thread_t        thread,
-       time_value_t    *user_time_p,
-       time_value_t    *system_time_p)
+processor_timer_switch_thread(uint64_t tstamp, timer_t new_timer)

 {
 {

-       timer_save_data_t       temp;
-       register timer_t        timer;
-
-       timer = &thread->user_timer;
-       db_timer_grab(timer, &temp);
+       processor_t processor = current_processor();
+       timer_t timer;

 
 

-#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;
-}
-
-/*
- *     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;
+       /* Update current timer. */
+       timer = PROCESSOR_DATA(processor, thread_timer);
+       timer_advance(timer, tstamp - timer->tstamp);

 
 

-       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);
+       /* Start new timer. */
+       PROCESSOR_DATA(processor, thread_timer) = new_timer;
+       new_timer->tstamp = tstamp;

 }
 }