X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/43866e378188c25dd1e2208016ab3cbeb086ae6c..8ad349bb6ed4a0be06e34c92be0d98b92e078db4:/osfmk/kern/priority.c diff --git a/osfmk/kern/priority.c b/osfmk/kern/priority.c index 23f5e43f0..a74ff74d4 100644 --- a/osfmk/kern/priority.c +++ b/osfmk/kern/priority.c @@ -1,26 +1,31 @@ /* - * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved. * - * @APPLE_LICENSE_HEADER_START@ + * @APPLE_LICENSE_OSREFERENCE_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 - * compliance with the License. Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this + * 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. 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, - * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. - * Please see the License for the specific language governing rights and + * + * 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, + * 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_OSREFERENCE_HEADER_END@ */ /* * @OSF_COPYRIGHT@ @@ -60,8 +65,6 @@ * Clock primitives. */ -#include - #include #include #include @@ -95,14 +98,12 @@ thread_quantum_expire( * Check for fail-safe trip. */ if (!(thread->sched_mode & TH_MODE_TIMESHARE)) { - extern uint64_t max_unsafe_computation; uint64_t new_computation; new_computation = myprocessor->quantum_end; new_computation -= thread->computation_epoch; if (new_computation + thread->computation_metered > max_unsafe_computation) { - extern uint32_t sched_safe_duration; if (thread->sched_mode & TH_MODE_REALTIME) { thread->priority = DEPRESSPRI; @@ -111,6 +112,8 @@ thread_quantum_expire( thread->sched_mode &= ~TH_MODE_REALTIME; } + pset_share_incr(thread->processor_set); + thread->safe_release = sched_tick + sched_safe_duration; thread->sched_mode |= (TH_MODE_FAILSAFE|TH_MODE_TIMESHARE); thread->sched_mode &= ~TH_MODE_PREEMPT; @@ -124,9 +127,19 @@ thread_quantum_expire( update_priority(thread); else if (thread->sched_mode & TH_MODE_TIMESHARE) { - thread_timer_delta(thread); - thread->sched_usage += thread->sched_delta; - thread->sched_delta = 0; + register uint32_t delta; + + thread_timer_delta(thread, delta); + + /* + * Accumulate timesharing usage only + * during contention for processor + * resources. + */ + if (thread->pri_shift < INT8_MAX) + thread->sched_usage += delta; + + thread->cpu_delta += delta; /* * Adjust the scheduled priority if @@ -141,11 +154,10 @@ thread_quantum_expire( /* * This quantum is up, give this thread another. */ - if (first_quantum(myprocessor)) - myprocessor->slice_quanta--; + if (first_timeslice(myprocessor)) + myprocessor->timeslice--; - thread->current_quantum = (thread->sched_mode & TH_MODE_REALTIME)? - thread->realtime.computation: std_quantum; + thread_quantum_init(thread); myprocessor->quantum_end += thread->current_quantum; timer_call_enter1(&myprocessor->quantum_timer, thread, myprocessor->quantum_end); @@ -159,3 +171,211 @@ thread_quantum_expire( splx(s); } + +/* + * Define shifts for simulating (5/8) ** n + * + * Shift structures for holding update shifts. Actual computation + * is usage = (usage >> shift1) +/- (usage >> abs(shift2)) where the + * +/- is determined by the sign of shift 2. + */ +struct shift_data { + int shift1; + int shift2; +}; + +#define SCHED_DECAY_TICKS 32 +static struct shift_data sched_decay_shifts[SCHED_DECAY_TICKS] = { + {1,1},{1,3},{1,-3},{2,-7},{3,5},{3,-5},{4,-8},{5,7}, + {5,-7},{6,-10},{7,10},{7,-9},{8,-11},{9,12},{9,-11},{10,-13}, + {11,14},{11,-13},{12,-15},{13,17},{13,-15},{14,-17},{15,19},{16,18}, + {16,-19},{17,22},{18,20},{18,-20},{19,26},{20,22},{20,-22},{21,-27} +}; + +/* + * do_priority_computation: + * + * Calculate the timesharing priority based upon usage and load. + */ +#define do_priority_computation(thread, pri) \ + MACRO_BEGIN \ + (pri) = (thread)->priority /* start with base priority */ \ + - ((thread)->sched_usage >> (thread)->pri_shift); \ + if ((pri) < MINPRI_USER) \ + (pri) = MINPRI_USER; \ + else \ + if ((pri) > MAXPRI_KERNEL) \ + (pri) = MAXPRI_KERNEL; \ + MACRO_END + +/* + * set_priority: + * + * Set the base priority of the thread + * and reset its scheduled priority. + * + * Called with the thread locked. + */ +void +set_priority( + register thread_t thread, + register int priority) +{ + thread->priority = priority; + compute_priority(thread, FALSE); +} + +/* + * compute_priority: + * + * Reset the scheduled priority of the thread + * according to its base priority if the + * thread has not been promoted or depressed. + * + * Called with the thread locked. + */ +void +compute_priority( + register thread_t thread, + boolean_t override_depress) +{ + register int priority; + + if ( !(thread->sched_mode & TH_MODE_PROMOTED) && + (!(thread->sched_mode & TH_MODE_ISDEPRESSED) || + override_depress ) ) { + if (thread->sched_mode & TH_MODE_TIMESHARE) + do_priority_computation(thread, priority); + else + priority = thread->priority; + + set_sched_pri(thread, priority); + } +} + +/* + * compute_my_priority: + * + * Reset the scheduled priority for + * a timesharing thread. + * + * Only for use on the current thread + * if timesharing and not depressed. + * + * Called with the thread locked. + */ +void +compute_my_priority( + register thread_t thread) +{ + register int priority; + + do_priority_computation(thread, priority); + assert(thread->runq == RUN_QUEUE_NULL); + thread->sched_pri = priority; +} + +/* + * update_priority + * + * Perform housekeeping operations driven by scheduler tick. + * + * Called with the thread locked. + */ +void +update_priority( + register thread_t thread) +{ + register unsigned ticks; + register uint32_t delta; + + ticks = sched_tick - thread->sched_stamp; + assert(ticks != 0); + thread->sched_stamp += ticks; + thread->pri_shift = thread->processor_set->pri_shift; + + /* + * Gather cpu usage data. + */ + thread_timer_delta(thread, delta); + if (ticks < SCHED_DECAY_TICKS) { + register struct shift_data *shiftp; + + /* + * Accumulate timesharing usage only + * during contention for processor + * resources. + */ + if (thread->pri_shift < INT8_MAX) + thread->sched_usage += delta; + + thread->cpu_usage += delta + thread->cpu_delta; + thread->cpu_delta = 0; + + shiftp = &sched_decay_shifts[ticks]; + if (shiftp->shift2 > 0) { + thread->cpu_usage = + (thread->cpu_usage >> shiftp->shift1) + + (thread->cpu_usage >> shiftp->shift2); + thread->sched_usage = + (thread->sched_usage >> shiftp->shift1) + + (thread->sched_usage >> shiftp->shift2); + } + else { + thread->cpu_usage = + (thread->cpu_usage >> shiftp->shift1) - + (thread->cpu_usage >> -(shiftp->shift2)); + thread->sched_usage = + (thread->sched_usage >> shiftp->shift1) - + (thread->sched_usage >> -(shiftp->shift2)); + } + } + else { + thread->cpu_usage = thread->cpu_delta = 0; + thread->sched_usage = 0; + } + + /* + * Check for fail-safe release. + */ + if ( (thread->sched_mode & TH_MODE_FAILSAFE) && + thread->sched_stamp >= thread->safe_release ) { + if (!(thread->safe_mode & TH_MODE_TIMESHARE)) { + if (thread->safe_mode & TH_MODE_REALTIME) { + thread->priority = BASEPRI_RTQUEUES; + + thread->sched_mode |= TH_MODE_REALTIME; + } + + thread->sched_mode &= ~TH_MODE_TIMESHARE; + + if (thread->state & TH_RUN) + pset_share_decr(thread->processor_set); + + if (!(thread->sched_mode & TH_MODE_ISDEPRESSED)) + set_sched_pri(thread, thread->priority); + } + + thread->safe_mode = 0; + thread->sched_mode &= ~TH_MODE_FAILSAFE; + } + + /* + * Recompute scheduled priority if appropriate. + */ + if ( (thread->sched_mode & TH_MODE_TIMESHARE) && + !(thread->sched_mode & TH_MODE_PROMOTED) && + !(thread->sched_mode & TH_MODE_ISDEPRESSED) ) { + register int new_pri; + + do_priority_computation(thread, new_pri); + if (new_pri != thread->sched_pri) { + run_queue_t runq; + + runq = run_queue_remove(thread); + thread->sched_pri = new_pri; + if (runq != RUN_QUEUE_NULL) + thread_setrun(thread, SCHED_TAILQ); + } + } +}