X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/490019cf9519204c5fb36b2fba54ceb983bb6b72..743345f9a4b36f7e2f9ba37691e70c50baecb56e:/osfmk/kern/priority.c?ds=inline diff --git a/osfmk/kern/priority.c b/osfmk/kern/priority.c index f50696079..f4f5b1cc8 100644 --- a/osfmk/kern/priority.c +++ b/osfmk/kern/priority.c @@ -81,6 +81,8 @@ #include /* for commpage_update_mach_approximate_time */ #endif +static void sched_update_thread_bucket(thread_t thread); + /* * thread_quantum_expire: * @@ -114,6 +116,9 @@ thread_quantum_expire( * Because this balance adjustment could potentially attempt to wake this very * thread, we must credit the ledger before taking the thread lock. The ledger * pointers are only manipulated by the thread itself at the ast boundary. + * + * TODO: This fails to account for the time between when the timer was armed and when it fired. + * It should be based on the system_timer and running a thread_timer_event operation here. */ ledger_credit(thread->t_ledger, task_ledgers.cpu_time, thread->quantum_remaining); ledger_credit(thread->t_threadledger, thread_ledgers.cpu_time, thread->quantum_remaining); @@ -235,15 +240,16 @@ thread_quantum_expire( void sched_set_thread_base_priority(thread_t thread, int priority) { - int old_priority = thread->base_pri; + assert(priority >= MINPRI); + + if (thread->sched_mode == TH_MODE_REALTIME) + assert(priority <= BASEPRI_RTQUEUES); + else + assert(priority < BASEPRI_RTQUEUES); + thread->base_pri = priority; - /* A thread is 'throttled' when its base priority is at or below MAXPRI_THROTTLE */ - if ((priority > MAXPRI_THROTTLE) && (old_priority <= MAXPRI_THROTTLE)) { - sched_set_thread_throttled(thread, FALSE); - } else if ((priority <= MAXPRI_THROTTLE) && (old_priority > MAXPRI_THROTTLE)) { - sched_set_thread_throttled(thread, TRUE); - } + sched_update_thread_bucket(thread); thread_recompute_sched_pri(thread, FALSE); } @@ -413,20 +419,16 @@ can_update_priority( */ void update_priority( - register thread_t thread) + thread_t thread) { - register unsigned ticks; - register uint32_t delta; + uint32_t ticks, delta; ticks = sched_tick - thread->sched_stamp; assert(ticks != 0); + thread->sched_stamp += ticks; - if (sched_use_combined_fgbg_decay) - thread->pri_shift = sched_combined_fgbg_pri_shift; - else if (thread->sched_flags & TH_SFLAG_THROTTLED) - thread->pri_shift = sched_background_pri_shift; - else - thread->pri_shift = sched_pri_shift; + + thread->pri_shift = sched_pri_shifts[thread->th_sched_bucket]; /* If requested, accelerate aging of sched_usage */ if (sched_decay_usage_age_factor > 1) @@ -437,8 +439,6 @@ update_priority( */ thread_timer_delta(thread, delta); if (ticks < SCHED_DECAY_TICKS) { - register struct shift_data *shiftp; - /* * Accumulate timesharing usage only * during contention for processor @@ -450,25 +450,20 @@ update_priority( thread->cpu_usage += delta + thread->cpu_delta; thread->cpu_delta = 0; - shiftp = &sched_decay_shifts[ticks]; + struct shift_data *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)); + 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 { + } else { thread->cpu_usage = thread->cpu_delta = 0; thread->sched_usage = 0; } @@ -516,86 +511,96 @@ update_priority( #endif /* CONFIG_SCHED_TIMESHARE_CORE */ -#if MACH_ASSERT -/* sched_mode == TH_MODE_TIMESHARE controls whether a thread has a timeshare count when it has a run count */ -void sched_share_incr(thread_t thread) { - assert((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN); - assert(thread->sched_mode == TH_MODE_TIMESHARE); - assert(thread->SHARE_COUNT == 0); - thread->SHARE_COUNT++; - (void)hw_atomic_add(&sched_share_count, 1); +/* + * TH_BUCKET_RUN is a count of *all* runnable non-idle threads. + * Each other bucket is a count of the runnable non-idle threads + * with that property. + */ +volatile uint32_t sched_run_buckets[TH_BUCKET_MAX]; + +static void +sched_incr_bucket(sched_bucket_t bucket) +{ + assert(bucket >= TH_BUCKET_FIXPRI && + bucket <= TH_BUCKET_SHARE_BG); + + hw_atomic_add(&sched_run_buckets[bucket], 1); } -void sched_share_decr(thread_t thread) { - assert((thread->state & (TH_RUN|TH_IDLE)) != TH_RUN || thread->sched_mode != TH_MODE_TIMESHARE); - assert(thread->SHARE_COUNT == 1); - (void)hw_atomic_sub(&sched_share_count, 1); - thread->SHARE_COUNT--; +static void +sched_decr_bucket(sched_bucket_t bucket) +{ + assert(bucket >= TH_BUCKET_FIXPRI && + bucket <= TH_BUCKET_SHARE_BG); + + assert(sched_run_buckets[bucket] > 0); + + hw_atomic_sub(&sched_run_buckets[bucket], 1); } -/* TH_SFLAG_THROTTLED controls whether a thread has a background count when it has a run count and a share count */ +/* TH_RUN & !TH_IDLE controls whether a thread has a run count */ -void sched_background_incr(thread_t thread) { +uint32_t +sched_run_incr(thread_t thread) +{ assert((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN); - assert(thread->sched_mode == TH_MODE_TIMESHARE); - assert((thread->sched_flags & TH_SFLAG_THROTTLED) == TH_SFLAG_THROTTLED); - assert(thread->BG_COUNT == 0); - thread->BG_COUNT++; - int val = hw_atomic_add(&sched_background_count, 1); - assert(val >= 0); + uint32_t new_count = hw_atomic_add(&sched_run_buckets[TH_BUCKET_RUN], 1); - /* Always do the background change while holding a share count */ - assert(thread->SHARE_COUNT == 1); -} + sched_incr_bucket(thread->th_sched_bucket); -void sched_background_decr(thread_t thread) { - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN && thread->sched_mode == TH_MODE_TIMESHARE) - assert((thread->sched_flags & TH_SFLAG_THROTTLED) != TH_SFLAG_THROTTLED); - assert(thread->BG_COUNT == 1); - int val = hw_atomic_sub(&sched_background_count, 1); - thread->BG_COUNT--; - assert(val >= 0); - assert(thread->BG_COUNT == 0); - - /* Always do the background change while holding a share count */ - assert(thread->SHARE_COUNT == 1); + return new_count; } +uint32_t +sched_run_decr(thread_t thread) +{ + assert((thread->state & (TH_RUN|TH_IDLE)) != TH_RUN); -void -assert_thread_sched_count(thread_t thread) { - /* Only 0 or 1 are acceptable values */ - assert(thread->BG_COUNT == 0 || thread->BG_COUNT == 1); - assert(thread->SHARE_COUNT == 0 || thread->SHARE_COUNT == 1); - - /* BG is only allowed when you already have a share count */ - if (thread->BG_COUNT == 1) - assert(thread->SHARE_COUNT == 1); - if (thread->SHARE_COUNT == 0) - assert(thread->BG_COUNT == 0); - - if ((thread->state & (TH_RUN|TH_IDLE)) != TH_RUN || - (thread->sched_mode != TH_MODE_TIMESHARE)) - assert(thread->SHARE_COUNT == 0); - - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN && - (thread->sched_mode == TH_MODE_TIMESHARE)) - assert(thread->SHARE_COUNT == 1); - - if ((thread->state & (TH_RUN|TH_IDLE)) != TH_RUN || - (thread->sched_mode != TH_MODE_TIMESHARE) || - !(thread->sched_flags & TH_SFLAG_THROTTLED)) - assert(thread->BG_COUNT == 0); - - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN && - (thread->sched_mode == TH_MODE_TIMESHARE) && - (thread->sched_flags & TH_SFLAG_THROTTLED)) - assert(thread->BG_COUNT == 1); + sched_decr_bucket(thread->th_sched_bucket); + + uint32_t new_count = hw_atomic_sub(&sched_run_buckets[TH_BUCKET_RUN], 1); + + return new_count; } -#endif /* MACH_ASSERT */ +static void +sched_update_thread_bucket(thread_t thread) +{ + sched_bucket_t old_bucket = thread->th_sched_bucket; + sched_bucket_t new_bucket = TH_BUCKET_RUN; + + switch (thread->sched_mode) { + case TH_MODE_FIXED: + case TH_MODE_REALTIME: + new_bucket = TH_BUCKET_FIXPRI; + break; + + case TH_MODE_TIMESHARE: + if (thread->base_pri > BASEPRI_UTILITY) + new_bucket = TH_BUCKET_SHARE_FG; + else if (thread->base_pri > MAXPRI_THROTTLE) + new_bucket = TH_BUCKET_SHARE_UT; + else + new_bucket = TH_BUCKET_SHARE_BG; + break; + + default: + panic("unexpected mode: %d", thread->sched_mode); + break; + } + + if (old_bucket != new_bucket) { + thread->th_sched_bucket = new_bucket; + thread->pri_shift = sched_pri_shifts[new_bucket]; + + if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN) { + sched_decr_bucket(old_bucket); + sched_incr_bucket(new_bucket); + } + } +} /* * Set the thread's true scheduling mode @@ -607,43 +612,22 @@ assert_thread_sched_count(thread_t thread) { void sched_set_thread_mode(thread_t thread, sched_mode_t new_mode) { - assert_thread_sched_count(thread); assert(thread->runq == PROCESSOR_NULL); - sched_mode_t old_mode = thread->sched_mode; - - thread->sched_mode = new_mode; - switch (new_mode) { - case TH_MODE_FIXED: - case TH_MODE_REALTIME: - if (old_mode == TH_MODE_TIMESHARE) { - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN) { - if (thread->sched_flags & TH_SFLAG_THROTTLED) - sched_background_decr(thread); - - sched_share_decr(thread); - } - } - break; - - case TH_MODE_TIMESHARE: - if (old_mode != TH_MODE_TIMESHARE) { - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN) { - sched_share_incr(thread); - - if (thread->sched_flags & TH_SFLAG_THROTTLED) - sched_background_incr(thread); - } - } - break; - - default: - panic("unexpected mode: %d", new_mode); - break; + case TH_MODE_FIXED: + case TH_MODE_REALTIME: + case TH_MODE_TIMESHARE: + break; + + default: + panic("unexpected mode: %d", new_mode); + break; } - assert_thread_sched_count(thread); + thread->sched_mode = new_mode; + + sched_update_thread_bucket(thread); } /* @@ -654,7 +638,6 @@ sched_thread_mode_demote(thread_t thread, uint32_t reason) { assert(reason & TH_SFLAG_DEMOTED_MASK); assert((thread->sched_flags & reason) != reason); - assert_thread_sched_count(thread); if (thread->policy_reset) return; @@ -679,8 +662,6 @@ sched_thread_mode_demote(thread_t thread, uint32_t reason) if (removed) thread_run_queue_reinsert(thread, SCHED_TAILQ); - - assert_thread_sched_count(thread); } /* @@ -695,8 +676,6 @@ sched_thread_mode_undemote(thread_t thread, uint32_t reason) assert(thread->sched_mode == TH_MODE_TIMESHARE); assert(thread->policy_reset == 0); - assert_thread_sched_count(thread); - thread->sched_flags &= ~reason; if (thread->sched_flags & TH_SFLAG_DEMOTED_MASK) { @@ -716,34 +695,4 @@ sched_thread_mode_undemote(thread_t thread, uint32_t reason) thread_run_queue_reinsert(thread, SCHED_TAILQ); } -/* - * Set the thread to be categorized as 'background' - * Called with thread mutex and thread lock held - * - * TODO: Eventually, 'background' should be a true sched_mode. - */ -void -sched_set_thread_throttled(thread_t thread, boolean_t wants_throttle) -{ - if (thread->policy_reset) - return; - - assert(((thread->sched_flags & TH_SFLAG_THROTTLED) ? TRUE : FALSE) != wants_throttle); - - assert_thread_sched_count(thread); - - if (wants_throttle) { - thread->sched_flags |= TH_SFLAG_THROTTLED; - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN && thread->sched_mode == TH_MODE_TIMESHARE) { - sched_background_incr(thread); - } - } else { - thread->sched_flags &= ~TH_SFLAG_THROTTLED; - if ((thread->state & (TH_RUN|TH_IDLE)) == TH_RUN && thread->sched_mode == TH_MODE_TIMESHARE) { - sched_background_decr(thread); - } - } - - assert_thread_sched_count(thread); -}