X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/39236c6e673c41db228275375ab7fdb0f837b292..c6bf4f310a33a9262d455ea4d3f0630b1255e3fe:/osfmk/kern/timer_call.c diff --git a/osfmk/kern/timer_call.c b/osfmk/kern/timer_call.c index a382c8607..06918edf5 100644 --- a/osfmk/kern/timer_call.c +++ b/osfmk/kern/timer_call.c @@ -2,7 +2,7 @@ * Copyright (c) 1993-2008 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ - * + * * 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 @@ -11,10 +11,10 @@ * 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, @@ -22,7 +22,7 @@ * 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_OSREFERENCE_LICENSE_HEADER_END@ */ /* @@ -32,11 +32,13 @@ #include #include +#include #include #include #include #include #include +#include #include @@ -46,7 +48,7 @@ #if DEBUG -#define TIMER_ASSERT 1 +#define TIMER_ASSERT 1 #endif //#define TIMER_ASSERT 1 @@ -59,7 +61,7 @@ #endif #if TIMER_TRACE -#define TIMER_KDEBUG_TRACE KERNEL_DEBUG_CONSTANT_IST +#define TIMER_KDEBUG_TRACE KERNEL_DEBUG_CONSTANT_IST #else #define TIMER_KDEBUG_TRACE(x...) #endif @@ -73,78 +75,106 @@ lck_grp_t timer_longterm_lck_grp; lck_attr_t timer_longterm_lck_attr; lck_grp_attr_t timer_longterm_lck_grp_attr; - -#define timer_queue_lock_spin(queue) \ +/* Timer queue lock must be acquired with interrupts disabled (under splclock()) */ +#if __SMP__ +#define timer_queue_lock_spin(queue) \ lck_mtx_lock_spin_always(&queue->lock_data) -#define timer_queue_unlock(queue) \ +#define timer_queue_unlock(queue) \ lck_mtx_unlock_always(&queue->lock_data) +#else +#define timer_queue_lock_spin(queue) (void)1 +#define timer_queue_unlock(queue) (void)1 +#endif - -#define QUEUE(x) ((queue_t)(x)) -#define MPQUEUE(x) ((mpqueue_head_t *)(x)) -#define TIMER_CALL(x) ((timer_call_t)(x)) - +#define QUEUE(x) ((queue_t)(x)) +#define MPQUEUE(x) ((mpqueue_head_t *)(x)) +#define TIMER_CALL(x) ((timer_call_t)(x)) +#define TCE(x) (&(x->call_entry)) /* * The longterm timer object is a global structure holding all timers * beyond the short-term, local timer queue threshold. The boot processor * is responsible for moving each timer to its local timer queue * if and when that timer becomes due within the threshold. */ -#define TIMER_LONGTERM_NONE EndOfAllTime + +/* Sentinel for "no time set": */ +#define TIMER_LONGTERM_NONE EndOfAllTime +/* The default threadhold is the delta above which a timer is "long-term" */ #if defined(__x86_64__) -#define TIMER_LONGTERM_THRESHOLD (1ULL * NSEC_PER_SEC) +#define TIMER_LONGTERM_THRESHOLD (1ULL * NSEC_PER_SEC) /* 1 sec */ #else -#define TIMER_LONGTERM_THRESHOLD TIMER_LONGTERM_NONE +#define TIMER_LONGTERM_THRESHOLD TIMER_LONGTERM_NONE /* disabled */ #endif +/* + * The scan_limit throttles processing of the longterm queue. + * If the scan time exceeds this limit, we terminate, unlock + * and defer for scan_interval. This prevents unbounded holding of + * timer queue locks with interrupts masked. + */ +#define TIMER_LONGTERM_SCAN_LIMIT (100ULL * NSEC_PER_USEC) /* 100 us */ +#define TIMER_LONGTERM_SCAN_INTERVAL (100ULL * NSEC_PER_USEC) /* 100 us */ +/* Sentinel for "scan limit exceeded": */ +#define TIMER_LONGTERM_SCAN_AGAIN 0 + typedef struct { - uint64_t interval; /* longterm timer interval */ - uint64_t margin; /* fudge factor (10% of interval */ - uint64_t deadline; /* first/soonest longterm deadline */ - uint64_t preempted; /* sooner timer has pre-empted */ - timer_call_t call; /* first/soonest longterm timer call */ - uint64_t deadline_set; /* next timer set */ - timer_call_data_t timer; /* timer used by threshold management */ - /* Stats: */ - uint64_t scans; /* num threshold timer scans */ - uint64_t preempts; /* num threshold reductions */ - uint64_t latency; /* average threshold latency */ - uint64_t latency_min; /* minimum threshold latency */ - uint64_t latency_max; /* maximum threshold latency */ + uint64_t interval; /* longterm timer interval */ + uint64_t margin; /* fudge factor (10% of interval */ + uint64_t deadline; /* first/soonest longterm deadline */ + uint64_t preempted; /* sooner timer has pre-empted */ + timer_call_t call; /* first/soonest longterm timer call */ + uint64_t deadline_set; /* next timer set */ + timer_call_data_t timer; /* timer used by threshold management */ + /* Stats: */ + uint64_t scans; /* num threshold timer scans */ + uint64_t preempts; /* num threshold reductions */ + uint64_t latency; /* average threshold latency */ + uint64_t latency_min; /* minimum threshold latency */ + uint64_t latency_max; /* maximum threshold latency */ } threshold_t; typedef struct { - mpqueue_head_t queue; /* longterm timer list */ - uint64_t enqueues; /* num timers queued */ - uint64_t dequeues; /* num timers dequeued */ - uint64_t escalates; /* num timers becoming shortterm */ - uint64_t scan_time; /* last time the list was scanned */ - threshold_t threshold; /* longterm timer threshold */ + mpqueue_head_t queue; /* longterm timer list */ + uint64_t enqueues; /* num timers queued */ + uint64_t dequeues; /* num timers dequeued */ + uint64_t escalates; /* num timers becoming shortterm */ + uint64_t scan_time; /* last time the list was scanned */ + threshold_t threshold; /* longterm timer threshold */ + uint64_t scan_limit; /* maximum scan time */ + uint64_t scan_interval; /* interval between LT "escalation" scans */ + uint64_t scan_pauses; /* num scans exceeding time limit */ } timer_longterm_t; -timer_longterm_t timer_longterm; - -static mpqueue_head_t *timer_longterm_queue = NULL; - -static void timer_longterm_init(void); -static void timer_longterm_callout( - timer_call_param_t p0, - timer_call_param_t p1); -extern void timer_longterm_scan( - timer_longterm_t *tlp, - uint64_t now); -static void timer_longterm_update( - timer_longterm_t *tlp); -static void timer_longterm_update_locked( - timer_longterm_t *tlp); -static mpqueue_head_t * timer_longterm_enqueue_unlocked( - timer_call_t call, - uint64_t now, - uint64_t deadline, - mpqueue_head_t ** old_queue); -static void timer_longterm_dequeued_locked( - timer_call_t call); +timer_longterm_t timer_longterm = { + .scan_limit = TIMER_LONGTERM_SCAN_LIMIT, + .scan_interval = TIMER_LONGTERM_SCAN_INTERVAL, +}; + +static mpqueue_head_t *timer_longterm_queue = NULL; + +static void timer_longterm_init(void); +static void timer_longterm_callout( + timer_call_param_t p0, + timer_call_param_t p1); +extern void timer_longterm_scan( + timer_longterm_t *tlp, + uint64_t now); +static void timer_longterm_update( + timer_longterm_t *tlp); +static void timer_longterm_update_locked( + timer_longterm_t *tlp); +static mpqueue_head_t * timer_longterm_enqueue_unlocked( + timer_call_t call, + uint64_t now, + uint64_t deadline, + mpqueue_head_t ** old_queue, + uint64_t soft_deadline, + uint64_t ttd, + timer_call_param_t param1, + uint32_t callout_flags); +static void timer_longterm_dequeued_locked( + timer_call_t call); uint64_t past_deadline_timers; uint64_t past_deadline_deltas; @@ -155,15 +185,66 @@ enum {PAST_DEADLINE_TIMER_ADJUSTMENT_NS = 10 * 1000}; uint64_t past_deadline_timer_adjustment; static boolean_t timer_call_enter_internal(timer_call_t call, timer_call_param_t param1, uint64_t deadline, uint64_t leeway, uint32_t flags, boolean_t ratelimited); -boolean_t mach_timer_coalescing_enabled = TRUE; +boolean_t mach_timer_coalescing_enabled = TRUE; -mpqueue_head_t *timer_call_enqueue_deadline_unlocked( - timer_call_t call, - mpqueue_head_t *queue, - uint64_t deadline); +mpqueue_head_t *timer_call_enqueue_deadline_unlocked( + timer_call_t call, + mpqueue_head_t *queue, + uint64_t deadline, + uint64_t soft_deadline, + uint64_t ttd, + timer_call_param_t param1, + uint32_t flags); + +mpqueue_head_t *timer_call_dequeue_unlocked( + timer_call_t call); + +timer_coalescing_priority_params_t tcoal_prio_params; + +#if TCOAL_PRIO_STATS +int32_t nc_tcl, rt_tcl, bg_tcl, kt_tcl, fp_tcl, ts_tcl, qos_tcl; +#define TCOAL_PRIO_STAT(x) (x++) +#else +#define TCOAL_PRIO_STAT(x) +#endif -mpqueue_head_t *timer_call_dequeue_unlocked( - timer_call_t call); +static void +timer_call_init_abstime(void) +{ + int i; + uint64_t result; + timer_coalescing_priority_params_ns_t * tcoal_prio_params_init = timer_call_get_priority_params(); + nanoseconds_to_absolutetime(PAST_DEADLINE_TIMER_ADJUSTMENT_NS, &past_deadline_timer_adjustment); + nanoseconds_to_absolutetime(tcoal_prio_params_init->idle_entry_timer_processing_hdeadline_threshold_ns, &result); + tcoal_prio_params.idle_entry_timer_processing_hdeadline_threshold_abstime = (uint32_t)result; + nanoseconds_to_absolutetime(tcoal_prio_params_init->interrupt_timer_coalescing_ilat_threshold_ns, &result); + tcoal_prio_params.interrupt_timer_coalescing_ilat_threshold_abstime = (uint32_t)result; + nanoseconds_to_absolutetime(tcoal_prio_params_init->timer_resort_threshold_ns, &result); + tcoal_prio_params.timer_resort_threshold_abstime = (uint32_t)result; + tcoal_prio_params.timer_coalesce_rt_shift = tcoal_prio_params_init->timer_coalesce_rt_shift; + tcoal_prio_params.timer_coalesce_bg_shift = tcoal_prio_params_init->timer_coalesce_bg_shift; + tcoal_prio_params.timer_coalesce_kt_shift = tcoal_prio_params_init->timer_coalesce_kt_shift; + tcoal_prio_params.timer_coalesce_fp_shift = tcoal_prio_params_init->timer_coalesce_fp_shift; + tcoal_prio_params.timer_coalesce_ts_shift = tcoal_prio_params_init->timer_coalesce_ts_shift; + + nanoseconds_to_absolutetime(tcoal_prio_params_init->timer_coalesce_rt_ns_max, + &tcoal_prio_params.timer_coalesce_rt_abstime_max); + nanoseconds_to_absolutetime(tcoal_prio_params_init->timer_coalesce_bg_ns_max, + &tcoal_prio_params.timer_coalesce_bg_abstime_max); + nanoseconds_to_absolutetime(tcoal_prio_params_init->timer_coalesce_kt_ns_max, + &tcoal_prio_params.timer_coalesce_kt_abstime_max); + nanoseconds_to_absolutetime(tcoal_prio_params_init->timer_coalesce_fp_ns_max, + &tcoal_prio_params.timer_coalesce_fp_abstime_max); + nanoseconds_to_absolutetime(tcoal_prio_params_init->timer_coalesce_ts_ns_max, + &tcoal_prio_params.timer_coalesce_ts_abstime_max); + + for (i = 0; i < NUM_LATENCY_QOS_TIERS; i++) { + tcoal_prio_params.latency_qos_scale[i] = tcoal_prio_params_init->latency_qos_scale[i]; + nanoseconds_to_absolutetime(tcoal_prio_params_init->latency_qos_ns_max[i], + &tcoal_prio_params.latency_qos_abstime_max[i]); + tcoal_prio_params.latency_tier_rate_limited[i] = tcoal_prio_params_init->latency_tier_rate_limited[i]; + } +} void @@ -172,9 +253,9 @@ timer_call_init(void) lck_attr_setdefault(&timer_call_lck_attr); lck_grp_attr_setdefault(&timer_call_lck_grp_attr); lck_grp_init(&timer_call_lck_grp, "timer_call", &timer_call_lck_grp_attr); - nanotime_to_absolutetime(0, PAST_DEADLINE_TIMER_ADJUSTMENT_NS, &past_deadline_timer_adjustment); timer_longterm_init(); + timer_call_init_abstime(); } @@ -188,122 +269,90 @@ timer_call_queue_init(mpqueue_head_t *queue) void timer_call_setup( - timer_call_t call, - timer_call_func_t func, - timer_call_param_t param0) + timer_call_t call, + timer_call_func_t func, + timer_call_param_t param0) { DBG("timer_call_setup(%p,%p,%p)\n", call, func, param0); - call_entry_setup(CE(call), func, param0); + call_entry_setup(TCE(call), func, param0); simple_lock_init(&(call)->lock, 0); call->async_dequeue = FALSE; } - -/* - * Timer call entry locking model - * ============================== - * - * Timer call entries are linked on per-cpu timer queues which are protected - * by the queue lock and the call entry lock. The locking protocol is: - * - * 0) The canonical locking order is timer call entry followed by queue. - * - * 1) With only the entry lock held, entry.queue is valid: - * 1a) NULL: the entry is not queued, or - * 1b) non-NULL: this queue must be locked before the entry is modified. - * After locking the queue, the call.async_dequeue flag must be checked: - * 1c) TRUE: the entry was removed from the queue by another thread - * and we must NULL the entry.queue and reset this flag, or - * 1d) FALSE: (ie. queued), the entry can be manipulated. - * - * 2) If a queue lock is obtained first, the queue is stable: - * 2a) If a try-lock of a queued entry succeeds, the call can be operated on - * and dequeued. - * 2b) If a try-lock fails, it indicates that another thread is attempting - * to change the entry and move it to a different position in this queue - * or to different queue. The entry can be dequeued but it should not be - * operated upon since it is being changed. Furthermore, we don't null - * the entry.queue pointer (protected by the entry lock we don't own). - * Instead, we set the async_dequeue flag -- see (1c). - * 2c) Same as 2b but occurring when a longterm timer is matured. - */ - -/* - * Inlines timer_call_entry_dequeue() and timer_call_entry_enqueue_deadline() - * cast between pointer types (mpqueue_head_t *) and (queue_t) so that - * we can use the call_entry_dequeue() and call_entry_enqueue_deadline() - * methods to operate on timer_call structs as if they are call_entry structs. - * These structures are identical except for their queue head pointer fields. - * - * In the debug case, we assert that the timer call locking protocol - * is being obeyed. - */ #if TIMER_ASSERT static __inline__ mpqueue_head_t * timer_call_entry_dequeue( - timer_call_t entry) + timer_call_t entry) { - mpqueue_head_t *old_queue = MPQUEUE(CE(entry)->queue); + mpqueue_head_t *old_queue = MPQUEUE(TCE(entry)->queue); - if (!hw_lock_held((hw_lock_t)&entry->lock)) + if (!hw_lock_held((hw_lock_t)&entry->lock)) { panic("_call_entry_dequeue() " - "entry %p is not locked\n", entry); + "entry %p is not locked\n", entry); + } /* * XXX The queue lock is actually a mutex in spin mode * but there's no way to test for it being held * so we pretend it's a spinlock! */ - if (!hw_lock_held((hw_lock_t)&old_queue->lock_data)) + if (!hw_lock_held((hw_lock_t)&old_queue->lock_data)) { panic("_call_entry_dequeue() " - "queue %p is not locked\n", old_queue); + "queue %p is not locked\n", old_queue); + } - call_entry_dequeue(CE(entry)); + call_entry_dequeue(TCE(entry)); old_queue->count--; - return (old_queue); + return old_queue; } static __inline__ mpqueue_head_t * timer_call_entry_enqueue_deadline( - timer_call_t entry, - mpqueue_head_t *queue, - uint64_t deadline) + timer_call_t entry, + mpqueue_head_t *queue, + uint64_t deadline) { - mpqueue_head_t *old_queue = MPQUEUE(CE(entry)->queue); + mpqueue_head_t *old_queue = MPQUEUE(TCE(entry)->queue); - if (!hw_lock_held((hw_lock_t)&entry->lock)) + if (!hw_lock_held((hw_lock_t)&entry->lock)) { panic("_call_entry_enqueue_deadline() " - "entry %p is not locked\n", entry); + "entry %p is not locked\n", entry); + } /* XXX More lock pretense: */ - if (!hw_lock_held((hw_lock_t)&queue->lock_data)) + if (!hw_lock_held((hw_lock_t)&queue->lock_data)) { panic("_call_entry_enqueue_deadline() " - "queue %p is not locked\n", queue); - if (old_queue != NULL && old_queue != queue) + "queue %p is not locked\n", queue); + } + if (old_queue != NULL && old_queue != queue) { panic("_call_entry_enqueue_deadline() " - "old_queue %p != queue", old_queue); + "old_queue %p != queue", old_queue); + } - call_entry_enqueue_deadline(CE(entry), QUEUE(queue), deadline); + call_entry_enqueue_deadline(TCE(entry), QUEUE(queue), deadline); /* For efficiency, track the earliest soft deadline on the queue, so that * fuzzy decisions can be made without lock acquisitions. */ - queue->earliest_soft_deadline = ((timer_call_t)queue_first(&queue->head))->soft_deadline; + timer_call_t thead = (timer_call_t)queue_first(&queue->head); - if (old_queue) + queue->earliest_soft_deadline = thead->flags & TIMER_CALL_RATELIMITED ? TCE(thead)->deadline : thead->soft_deadline; + + if (old_queue) { old_queue->count--; + } queue->count++; - return (old_queue); + return old_queue; } #else static __inline__ mpqueue_head_t * timer_call_entry_dequeue( - timer_call_t entry) + timer_call_t entry) { - mpqueue_head_t *old_queue = MPQUEUE(CE(entry)->queue); + mpqueue_head_t *old_queue = MPQUEUE(TCE(entry)->queue); - call_entry_dequeue(CE(entry)); + call_entry_dequeue(TCE(entry)); old_queue->count--; return old_queue; @@ -311,21 +360,24 @@ timer_call_entry_dequeue( static __inline__ mpqueue_head_t * timer_call_entry_enqueue_deadline( - timer_call_t entry, - mpqueue_head_t *queue, - uint64_t deadline) + timer_call_t entry, + mpqueue_head_t *queue, + uint64_t deadline) { - mpqueue_head_t *old_queue = MPQUEUE(CE(entry)->queue); + mpqueue_head_t *old_queue = MPQUEUE(TCE(entry)->queue); - call_entry_enqueue_deadline(CE(entry), QUEUE(queue), deadline); + call_entry_enqueue_deadline(TCE(entry), QUEUE(queue), deadline); /* For efficiency, track the earliest soft deadline on the queue, * so that fuzzy decisions can be made without lock acquisitions. */ - queue->earliest_soft_deadline = ((timer_call_t)queue_first(&queue->head))->soft_deadline; - if (old_queue) + timer_call_t thead = (timer_call_t)queue_first(&queue->head); + queue->earliest_soft_deadline = thead->flags & TIMER_CALL_RATELIMITED ? TCE(thead)->deadline : thead->soft_deadline; + + if (old_queue) { old_queue->count--; + } queue->count++; return old_queue; @@ -335,10 +387,10 @@ timer_call_entry_enqueue_deadline( static __inline__ void timer_call_entry_enqueue_tail( - timer_call_t entry, - mpqueue_head_t *queue) + timer_call_t entry, + mpqueue_head_t *queue) { - call_entry_enqueue_tail(CE(entry), QUEUE(queue)); + call_entry_enqueue_tail(TCE(entry), QUEUE(queue)); queue->count++; return; } @@ -349,9 +401,9 @@ timer_call_entry_enqueue_tail( */ static __inline__ void timer_call_entry_dequeue_async( - timer_call_t entry) + timer_call_t entry) { - mpqueue_head_t *old_queue = MPQUEUE(CE(entry)->queue); + mpqueue_head_t *old_queue = MPQUEUE(TCE(entry)->queue); if (old_queue) { old_queue->count--; (void) remque(qe(entry)); @@ -369,28 +421,34 @@ unsigned timer_call_enqueue_deadline_unlocked_async2; */ __inline__ mpqueue_head_t * timer_call_enqueue_deadline_unlocked( - timer_call_t call, - mpqueue_head_t *queue, - uint64_t deadline) + timer_call_t call, + mpqueue_head_t *queue, + uint64_t deadline, + uint64_t soft_deadline, + uint64_t ttd, + timer_call_param_t param1, + uint32_t callout_flags) { - call_entry_t entry = CE(call); - mpqueue_head_t *old_queue; + call_entry_t entry = TCE(call); + mpqueue_head_t *old_queue; DBG("timer_call_enqueue_deadline_unlocked(%p,%p,)\n", call, queue); - simple_lock(&call->lock); + simple_lock(&call->lock, LCK_GRP_NULL); + old_queue = MPQUEUE(entry->queue); + if (old_queue != NULL) { timer_queue_lock_spin(old_queue); if (call->async_dequeue) { /* collision (1c): timer already dequeued, clear flag */ #if TIMER_ASSERT - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, - call, - call->async_dequeue, - CE(call)->queue, - 0x1c, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + call->async_dequeue, + VM_KERNEL_UNSLIDE_OR_PERM(TCE(call)->queue), + 0x1c, 0); timer_call_enqueue_deadline_unlocked_async1++; #endif call->async_dequeue = FALSE; @@ -401,8 +459,9 @@ timer_call_enqueue_deadline_unlocked( timer_call_enqueue_deadline_unlocked_async2++; #endif } - if (old_queue == timer_longterm_queue) + if (old_queue == timer_longterm_queue) { timer_longterm_dequeued_locked(call); + } if (old_queue != queue) { timer_queue_unlock(old_queue); timer_queue_lock_spin(queue); @@ -411,11 +470,16 @@ timer_call_enqueue_deadline_unlocked( timer_queue_lock_spin(queue); } + call->soft_deadline = soft_deadline; + call->flags = callout_flags; + TCE(call)->param1 = param1; + call->ttd = ttd; + timer_call_entry_enqueue_deadline(call, queue, deadline); timer_queue_unlock(queue); simple_unlock(&call->lock); - return (old_queue); + return old_queue; } #if TIMER_ASSERT @@ -424,34 +488,34 @@ unsigned timer_call_dequeue_unlocked_async2; #endif mpqueue_head_t * timer_call_dequeue_unlocked( - timer_call_t call) + timer_call_t call) { - call_entry_t entry = CE(call); - mpqueue_head_t *old_queue; + call_entry_t entry = TCE(call); + mpqueue_head_t *old_queue; DBG("timer_call_dequeue_unlocked(%p)\n", call); - simple_lock(&call->lock); + simple_lock(&call->lock, LCK_GRP_NULL); old_queue = MPQUEUE(entry->queue); #if TIMER_ASSERT - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, - call, - call->async_dequeue, - CE(call)->queue, - 0, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + call->async_dequeue, + VM_KERNEL_UNSLIDE_OR_PERM(TCE(call)->queue), + 0, 0); #endif if (old_queue != NULL) { timer_queue_lock_spin(old_queue); if (call->async_dequeue) { /* collision (1c): timer already dequeued, clear flag */ #if TIMER_ASSERT - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, - call, - call->async_dequeue, - CE(call)->queue, - 0x1c, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + call->async_dequeue, + VM_KERNEL_UNSLIDE_OR_PERM(TCE(call)->queue), + 0x1c, 0); timer_call_dequeue_unlocked_async1++; #endif call->async_dequeue = FALSE; @@ -459,48 +523,111 @@ timer_call_dequeue_unlocked( } else { timer_call_entry_dequeue(call); } - if (old_queue == timer_longterm_queue) + if (old_queue == timer_longterm_queue) { timer_longterm_dequeued_locked(call); + } timer_queue_unlock(old_queue); } simple_unlock(&call->lock); - return (old_queue); + return old_queue; } -static boolean_t -timer_call_enter_internal( - timer_call_t call, - timer_call_param_t param1, - uint64_t deadline, - uint64_t leeway, - uint32_t flags, - boolean_t ratelimited) +static uint64_t +past_deadline_timer_handle(uint64_t deadline, uint64_t ctime) { - mpqueue_head_t *queue = NULL; - mpqueue_head_t *old_queue; - spl_t s; - uint64_t slop; - uint32_t urgency; + uint64_t delta = (ctime - deadline); - s = splclock(); + past_deadline_timers++; + past_deadline_deltas += delta; + if (delta > past_deadline_longest) { + past_deadline_longest = deadline; + } + if (delta < past_deadline_shortest) { + past_deadline_shortest = delta; + } - call->soft_deadline = deadline; - call->flags = flags; + return ctime + past_deadline_timer_adjustment; +} +/* + * Timer call entry locking model + * ============================== + * + * Timer call entries are linked on per-cpu timer queues which are protected + * by the queue lock and the call entry lock. The locking protocol is: + * + * 0) The canonical locking order is timer call entry followed by queue. + * + * 1) With only the entry lock held, entry.queue is valid: + * 1a) NULL: the entry is not queued, or + * 1b) non-NULL: this queue must be locked before the entry is modified. + * After locking the queue, the call.async_dequeue flag must be checked: + * 1c) TRUE: the entry was removed from the queue by another thread + * and we must NULL the entry.queue and reset this flag, or + * 1d) FALSE: (ie. queued), the entry can be manipulated. + * + * 2) If a queue lock is obtained first, the queue is stable: + * 2a) If a try-lock of a queued entry succeeds, the call can be operated on + * and dequeued. + * 2b) If a try-lock fails, it indicates that another thread is attempting + * to change the entry and move it to a different position in this queue + * or to different queue. The entry can be dequeued but it should not be + * operated upon since it is being changed. Furthermore, we don't null + * the entry.queue pointer (protected by the entry lock we don't own). + * Instead, we set the async_dequeue flag -- see (1c). + * 2c) Same as 2b but occurring when a longterm timer is matured. + * 3) A callout's parameters (deadline, flags, parameters, soft deadline &c.) + * should be manipulated with the appropriate timer queue lock held, + * to prevent queue traversal observations from observing inconsistent + * updates to an in-flight callout. + */ + +/* + * Inlines timer_call_entry_dequeue() and timer_call_entry_enqueue_deadline() + * cast between pointer types (mpqueue_head_t *) and (queue_t) so that + * we can use the call_entry_dequeue() and call_entry_enqueue_deadline() + * methods to operate on timer_call structs as if they are call_entry structs. + * These structures are identical except for their queue head pointer fields. + * + * In the debug case, we assert that the timer call locking protocol + * is being obeyed. + */ + +static boolean_t +timer_call_enter_internal( + timer_call_t call, + timer_call_param_t param1, + uint64_t deadline, + uint64_t leeway, + uint32_t flags, + boolean_t ratelimited) +{ + mpqueue_head_t *queue = NULL; + mpqueue_head_t *old_queue; + spl_t s; + uint64_t slop; + uint32_t urgency; + uint64_t sdeadline, ttd; + + assert(call->call_entry.func != NULL); + s = splclock(); + + sdeadline = deadline; uint64_t ctime = mach_absolute_time(); TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ENTER | DBG_FUNC_START, - call, - param1, deadline, flags, 0); + DECR_TIMER_ENTER | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(call), + VM_KERNEL_ADDRHIDE(param1), deadline, flags, 0); urgency = (flags & TIMER_CALL_URGENCY_MASK); boolean_t slop_ratelimited = FALSE; slop = timer_call_slop(deadline, ctime, urgency, current_thread(), &slop_ratelimited); - if ((flags & TIMER_CALL_LEEWAY) != 0 && leeway > slop) + if ((flags & TIMER_CALL_LEEWAY) != 0 && leeway > slop) { slop = leeway; + } if (UINT64_MAX - deadline <= slop) { deadline = UINT64_MAX; @@ -509,63 +636,49 @@ timer_call_enter_internal( } if (__improbable(deadline < ctime)) { - uint64_t delta = (ctime - deadline); - - past_deadline_timers++; - past_deadline_deltas += delta; - if (delta > past_deadline_longest) - past_deadline_longest = deadline; - if (delta < past_deadline_shortest) - past_deadline_shortest = delta; - - deadline = ctime + past_deadline_timer_adjustment; - call->soft_deadline = deadline; + deadline = past_deadline_timer_handle(deadline, ctime); + sdeadline = deadline; } - /* Bit 0 of the "soft" deadline indicates that - * this particular timer call requires rate-limiting - * behaviour. Maintain the invariant deadline >= soft_deadline by - * setting bit 0 of "deadline". - */ - - deadline |= 1; if (ratelimited || slop_ratelimited) { - call->soft_deadline |= 1ULL; + flags |= TIMER_CALL_RATELIMITED; } else { - call->soft_deadline &= ~0x1ULL; + flags &= ~TIMER_CALL_RATELIMITED; } - call->ttd = call->soft_deadline - ctime; - + ttd = sdeadline - ctime; #if CONFIG_DTRACE - DTRACE_TMR7(callout__create, timer_call_func_t, CE(call)->func, - timer_call_param_t, CE(call)->param0, uint32_t, call->flags, - (deadline - call->soft_deadline), - (call->ttd >> 32), (unsigned) (call->ttd & 0xFFFFFFFF), call); + DTRACE_TMR7(callout__create, timer_call_func_t, TCE(call)->func, + timer_call_param_t, TCE(call)->param0, uint32_t, flags, + (deadline - sdeadline), + (ttd >> 32), (unsigned) (ttd & 0xFFFFFFFF), call); #endif + /* Program timer callout parameters under the appropriate per-CPU or + * longterm queue lock. The callout may have been previously enqueued + * and in-flight on this or another timer queue. + */ if (!ratelimited && !slop_ratelimited) { - queue = timer_longterm_enqueue_unlocked(call, ctime, deadline, &old_queue); + queue = timer_longterm_enqueue_unlocked(call, ctime, deadline, &old_queue, sdeadline, ttd, param1, flags); } if (queue == NULL) { queue = timer_queue_assign(deadline); - old_queue = timer_call_enqueue_deadline_unlocked(call, queue, deadline); + old_queue = timer_call_enqueue_deadline_unlocked(call, queue, deadline, sdeadline, ttd, param1, flags); } - CE(call)->param1 = param1; #if TIMER_TRACE - CE(call)->entry_time = ctime; + TCE(call)->entry_time = ctime; #endif TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ENTER | DBG_FUNC_END, - call, - (old_queue != NULL), call->soft_deadline, queue->count, 0); + DECR_TIMER_ENTER | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(call), + (old_queue != NULL), deadline, queue->count, 0); splx(s); - return (old_queue != NULL); + return old_queue != NULL; } /* @@ -574,97 +687,176 @@ timer_call_enter_internal( */ boolean_t timer_call_enter( - timer_call_t call, - uint64_t deadline, - uint32_t flags) + timer_call_t call, + uint64_t deadline, + uint32_t flags) { return timer_call_enter_internal(call, NULL, deadline, 0, flags, FALSE); } boolean_t timer_call_enter1( - timer_call_t call, - timer_call_param_t param1, - uint64_t deadline, - uint32_t flags) + timer_call_t call, + timer_call_param_t param1, + uint64_t deadline, + uint32_t flags) { return timer_call_enter_internal(call, param1, deadline, 0, flags, FALSE); } boolean_t timer_call_enter_with_leeway( - timer_call_t call, - timer_call_param_t param1, - uint64_t deadline, - uint64_t leeway, - uint32_t flags, - boolean_t ratelimited) + timer_call_t call, + timer_call_param_t param1, + uint64_t deadline, + uint64_t leeway, + uint32_t flags, + boolean_t ratelimited) { return timer_call_enter_internal(call, param1, deadline, leeway, flags, ratelimited); } +boolean_t +timer_call_quantum_timer_enter( + timer_call_t call, + timer_call_param_t param1, + uint64_t deadline, + uint64_t ctime) +{ + assert(call->call_entry.func != NULL); + assert(ml_get_interrupts_enabled() == FALSE); + + uint32_t flags = TIMER_CALL_SYS_CRITICAL | TIMER_CALL_LOCAL; + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, DECR_TIMER_ENTER | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(call), + VM_KERNEL_ADDRHIDE(param1), deadline, + flags, 0); + + if (__improbable(deadline < ctime)) { + deadline = past_deadline_timer_handle(deadline, ctime); + } + + uint64_t ttd = deadline - ctime; +#if CONFIG_DTRACE + DTRACE_TMR7(callout__create, timer_call_func_t, TCE(call)->func, + timer_call_param_t, TCE(call)->param0, uint32_t, flags, 0, + (ttd >> 32), (unsigned) (ttd & 0xFFFFFFFF), call); +#endif + + quantum_timer_set_deadline(deadline); + TCE(call)->deadline = deadline; + TCE(call)->param1 = param1; + call->ttd = ttd; + call->flags = flags; + +#if TIMER_TRACE + TCE(call)->entry_time = ctime; +#endif + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, DECR_TIMER_ENTER | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(call), + 1, deadline, 0, 0); + + return true; +} + + +boolean_t +timer_call_quantum_timer_cancel( + timer_call_t call) +{ + assert(ml_get_interrupts_enabled() == FALSE); + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_CANCEL | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(call), TCE(call)->deadline, + 0, call->flags, 0); + + TCE(call)->deadline = 0; + quantum_timer_set_deadline(0); + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_CANCEL | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(call), 0, + TCE(call)->deadline - mach_absolute_time(), + TCE(call)->deadline - TCE(call)->entry_time, 0); + +#if CONFIG_DTRACE + DTRACE_TMR6(callout__cancel, timer_call_func_t, TCE(call)->func, + timer_call_param_t, TCE(call)->param0, uint32_t, call->flags, 0, + (call->ttd >> 32), (unsigned) (call->ttd & 0xFFFFFFFF)); +#endif + + return true; +} + boolean_t timer_call_cancel( - timer_call_t call) + timer_call_t call) { - mpqueue_head_t *old_queue; - spl_t s; + mpqueue_head_t *old_queue; + spl_t s; s = splclock(); TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_CANCEL | DBG_FUNC_START, - call, - CE(call)->deadline, call->soft_deadline, call->flags, 0); + DECR_TIMER_CANCEL | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(call), + TCE(call)->deadline, call->soft_deadline, call->flags, 0); old_queue = timer_call_dequeue_unlocked(call); if (old_queue != NULL) { timer_queue_lock_spin(old_queue); if (!queue_empty(&old_queue->head)) { - timer_queue_cancel(old_queue, CE(call)->deadline, CE(queue_first(&old_queue->head))->deadline); - old_queue->earliest_soft_deadline = ((timer_call_t)queue_first(&old_queue->head))->soft_deadline; - } - else { - timer_queue_cancel(old_queue, CE(call)->deadline, UINT64_MAX); + timer_queue_cancel(old_queue, TCE(call)->deadline, CE(queue_first(&old_queue->head))->deadline); + timer_call_t thead = (timer_call_t)queue_first(&old_queue->head); + old_queue->earliest_soft_deadline = thead->flags & TIMER_CALL_RATELIMITED ? TCE(thead)->deadline : thead->soft_deadline; + } else { + timer_queue_cancel(old_queue, TCE(call)->deadline, UINT64_MAX); old_queue->earliest_soft_deadline = UINT64_MAX; } timer_queue_unlock(old_queue); } TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_CANCEL | DBG_FUNC_END, - call, - old_queue, - CE(call)->deadline - mach_absolute_time(), - CE(call)->deadline - CE(call)->entry_time, 0); + DECR_TIMER_CANCEL | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(call), + VM_KERNEL_UNSLIDE_OR_PERM(old_queue), + TCE(call)->deadline - mach_absolute_time(), + TCE(call)->deadline - TCE(call)->entry_time, 0); splx(s); #if CONFIG_DTRACE - DTRACE_TMR6(callout__cancel, timer_call_func_t, CE(call)->func, - timer_call_param_t, CE(call)->param0, uint32_t, call->flags, 0, + DTRACE_TMR6(callout__cancel, timer_call_func_t, TCE(call)->func, + timer_call_param_t, TCE(call)->param0, uint32_t, call->flags, 0, (call->ttd >> 32), (unsigned) (call->ttd & 0xFFFFFFFF)); #endif - return (old_queue != NULL); + return old_queue != NULL; } -uint32_t timer_queue_shutdown_lock_skips; +static uint32_t timer_queue_shutdown_lock_skips; +static uint32_t timer_queue_shutdown_discarded; + void timer_queue_shutdown( - mpqueue_head_t *queue) + mpqueue_head_t *queue) { - timer_call_t call; - mpqueue_head_t *new_queue; - spl_t s; + timer_call_t call; + mpqueue_head_t *new_queue; + spl_t s; + DBG("timer_queue_shutdown(%p)\n", queue); s = splclock(); /* Note comma operator in while expression re-locking each iteration */ - while (timer_queue_lock_spin(queue), !queue_empty(&queue->head)) { + while ((void)timer_queue_lock_spin(queue), !queue_empty(&queue->head)) { call = TIMER_CALL(queue_first(&queue->head)); - if (!simple_lock_try(&call->lock)) { + + if (!simple_lock_try(&call->lock, LCK_GRP_NULL)) { /* * case (2b) lock order inversion, dequeue and skip * Don't change the call_entry queue back-pointer @@ -673,28 +865,35 @@ timer_queue_shutdown( timer_queue_shutdown_lock_skips++; timer_call_entry_dequeue_async(call); #if TIMER_ASSERT - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, - call, - call->async_dequeue, - CE(call)->queue, - 0x2b, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + call->async_dequeue, + VM_KERNEL_UNSLIDE_OR_PERM(TCE(call)->queue), + 0x2b, 0); #endif timer_queue_unlock(queue); continue; } + boolean_t call_local = ((call->flags & TIMER_CALL_LOCAL) != 0); + /* remove entry from old queue */ timer_call_entry_dequeue(call); timer_queue_unlock(queue); - /* and queue it on new */ - new_queue = timer_queue_assign(CE(call)->deadline); - timer_queue_lock_spin(new_queue); - timer_call_entry_enqueue_deadline( - call, new_queue, CE(call)->deadline); - timer_queue_unlock(new_queue); + if (call_local == FALSE) { + /* and queue it on new, discarding LOCAL timers */ + new_queue = timer_queue_assign(TCE(call)->deadline); + timer_queue_lock_spin(new_queue); + timer_call_entry_enqueue_deadline( + call, new_queue, TCE(call)->deadline); + timer_queue_unlock(new_queue); + } else { + timer_queue_shutdown_discarded++; + } + assert(call_local == FALSE); simple_unlock(&call->lock); } @@ -702,14 +901,60 @@ timer_queue_shutdown( splx(s); } -uint32_t timer_queue_expire_lock_skips; + +void +quantum_timer_expire( + uint64_t deadline) +{ + processor_t processor = current_processor(); + timer_call_t call = TIMER_CALL(&(processor->quantum_timer)); + + if (__improbable(TCE(call)->deadline > deadline)) { + panic("CPU quantum timer deadlin out of sync with timer call deadline"); + } + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_EXPIRE | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + TCE(call)->deadline, + TCE(call)->deadline, + TCE(call)->entry_time, 0); + + timer_call_func_t func = TCE(call)->func; + timer_call_param_t param0 = TCE(call)->param0; + timer_call_param_t param1 = TCE(call)->param1; + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_CALLOUT | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(call), VM_KERNEL_UNSLIDE(func), + VM_KERNEL_ADDRHIDE(param0), + VM_KERNEL_ADDRHIDE(param1), + 0); + +#if CONFIG_DTRACE + DTRACE_TMR7(callout__start, timer_call_func_t, func, + timer_call_param_t, param0, unsigned, call->flags, + 0, (call->ttd >> 32), + (unsigned) (call->ttd & 0xFFFFFFFF), call); +#endif + (*func)(param0, param1); + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_CALLOUT | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(call), VM_KERNEL_UNSLIDE(func), + VM_KERNEL_ADDRHIDE(param0), + VM_KERNEL_ADDRHIDE(param1), + 0); +} + +static uint32_t timer_queue_expire_lock_skips; uint64_t timer_queue_expire_with_options( - mpqueue_head_t *queue, - uint64_t deadline, - boolean_t rescan) + mpqueue_head_t *queue, + uint64_t deadline, + boolean_t rescan) { - timer_call_t call = NULL; + timer_call_t call = NULL; uint32_t tc_iterations = 0; DBG("timer_queue_expire(%p,)\n", queue); @@ -720,36 +965,34 @@ timer_queue_expire_with_options( /* Upon processing one or more timer calls, refresh the * deadline to account for time elapsed in the callout */ - if (++tc_iterations > 1) + if (++tc_iterations > 1) { cur_deadline = mach_absolute_time(); + } - if (call == NULL) + if (call == NULL) { call = TIMER_CALL(queue_first(&queue->head)); + } if (call->soft_deadline <= cur_deadline) { - timer_call_func_t func; - timer_call_param_t param0, param1; + timer_call_func_t func; + timer_call_param_t param0, param1; TCOAL_DEBUG(0xDDDD0000, queue->earliest_soft_deadline, call->soft_deadline, 0, 0, 0); - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_EXPIRE | DBG_FUNC_NONE, - call, - call->soft_deadline, - CE(call)->deadline, - CE(call)->entry_time, 0); - - /* Bit 0 of the "soft" deadline indicates that - * this particular timer call is rate-limited - * and hence shouldn't be processed before its - * hard deadline. - */ - if ((call->soft_deadline & 0x1) && - (CE(call)->deadline > cur_deadline)) { - if (rescan == FALSE) + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_EXPIRE | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + call->soft_deadline, + TCE(call)->deadline, + TCE(call)->entry_time, 0); + + if ((call->flags & TIMER_CALL_RATELIMITED) && + (TCE(call)->deadline > cur_deadline)) { + if (rescan == FALSE) { break; + } } - if (!simple_lock_try(&call->lock)) { + if (!simple_lock_try(&call->lock, LCK_GRP_NULL)) { /* case (2b) lock inversion, dequeue and skip */ timer_queue_expire_lock_skips++; timer_call_entry_dequeue_async(call); @@ -759,16 +1002,19 @@ timer_queue_expire_with_options( timer_call_entry_dequeue(call); - func = CE(call)->func; - param0 = CE(call)->param0; - param1 = CE(call)->param1; + func = TCE(call)->func; + param0 = TCE(call)->param0; + param1 = TCE(call)->param1; simple_unlock(&call->lock); timer_queue_unlock(queue); - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_CALLOUT | DBG_FUNC_START, - call, VM_KERNEL_UNSLIDE(func), param0, param1, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_CALLOUT | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(call), VM_KERNEL_UNSLIDE(func), + VM_KERNEL_ADDRHIDE(param0), + VM_KERNEL_ADDRHIDE(param1), + 0); #if CONFIG_DTRACE DTRACE_TMR7(callout__start, timer_call_func_t, func, @@ -788,17 +1034,20 @@ timer_queue_expire_with_options( param0, param1, call); #endif - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_CALLOUT | DBG_FUNC_END, - call, VM_KERNEL_UNSLIDE(func), param0, param1, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_CALLOUT | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(call), VM_KERNEL_UNSLIDE(func), + VM_KERNEL_ADDRHIDE(param0), + VM_KERNEL_ADDRHIDE(param1), + 0); call = NULL; timer_queue_lock_spin(queue); } else { if (__probable(rescan == FALSE)) { break; } else { - int64_t skew = CE(call)->deadline - call->soft_deadline; - assert(CE(call)->deadline >= call->soft_deadline); + int64_t skew = TCE(call)->deadline - call->soft_deadline; + assert(TCE(call)->deadline >= call->soft_deadline); /* DRK: On a latency quality-of-service level change, * re-sort potentially rate-limited timers. The platform @@ -809,9 +1058,9 @@ timer_queue_expire_with_options( * annuls all timer adjustments, i.e. the "soft * deadline" is the sort key. */ - + if (timer_resort_threshold(skew)) { - if (__probable(simple_lock_try(&call->lock))) { + if (__probable(simple_lock_try(&call->lock, LCK_GRP_NULL))) { timer_call_entry_dequeue(call); timer_call_entry_enqueue_deadline(call, queue, call->soft_deadline); simple_unlock(&call->lock); @@ -820,8 +1069,9 @@ timer_queue_expire_with_options( } if (call) { call = TIMER_CALL(queue_next(qe(call))); - if (queue_end(&queue->head, qe(call))) + if (queue_end(&queue->head, qe(call))) { break; + } } } } @@ -829,27 +1079,27 @@ timer_queue_expire_with_options( if (!queue_empty(&queue->head)) { call = TIMER_CALL(queue_first(&queue->head)); - cur_deadline = CE(call)->deadline; - queue->earliest_soft_deadline = call->soft_deadline; + cur_deadline = TCE(call)->deadline; + queue->earliest_soft_deadline = (call->flags & TIMER_CALL_RATELIMITED) ? TCE(call)->deadline: call->soft_deadline; } else { queue->earliest_soft_deadline = cur_deadline = UINT64_MAX; } timer_queue_unlock(queue); - return (cur_deadline); + return cur_deadline; } uint64_t timer_queue_expire( - mpqueue_head_t *queue, - uint64_t deadline) + mpqueue_head_t *queue, + uint64_t deadline) { return timer_queue_expire_with_options(queue, deadline, FALSE); } extern int serverperfmode; -uint32_t timer_queue_migrate_lock_skips; +static uint32_t timer_queue_migrate_lock_skips; /* * timer_queue_migrate() is called by timer_queue_migrate_cpu() * to move timer requests from the local processor (queue_from) @@ -858,9 +1108,9 @@ uint32_t timer_queue_migrate_lock_skips; int timer_queue_migrate(mpqueue_head_t *queue_from, mpqueue_head_t *queue_to) { - timer_call_t call; - timer_call_t head_to; - int timers_migrated = 0; + timer_call_t call; + timer_call_t head_to; + int timers_migrated = 0; DBG("timer_queue_migrate(%p,%p)\n", queue_from, queue_to); @@ -889,7 +1139,7 @@ timer_queue_migrate(mpqueue_head_t *queue_from, mpqueue_head_t *queue_to) * so that we need not have the target resync. */ - timer_queue_lock_spin(queue_to); + timer_queue_lock_spin(queue_to); head_to = TIMER_CALL(queue_first(&queue_to->head)); if (queue_empty(&queue_to->head)) { @@ -897,7 +1147,7 @@ timer_queue_migrate(mpqueue_head_t *queue_from, mpqueue_head_t *queue_to) goto abort1; } - timer_queue_lock_spin(queue_from); + timer_queue_lock_spin(queue_from); if (queue_empty(&queue_from->head)) { timers_migrated = -2; @@ -905,7 +1155,7 @@ timer_queue_migrate(mpqueue_head_t *queue_from, mpqueue_head_t *queue_to) } call = TIMER_CALL(queue_first(&queue_from->head)); - if (CE(call)->deadline < CE(head_to)->deadline) { + if (TCE(call)->deadline < TCE(head_to)->deadline) { timers_migrated = 0; goto abort2; } @@ -922,15 +1172,15 @@ timer_queue_migrate(mpqueue_head_t *queue_from, mpqueue_head_t *queue_to) /* migration loop itself -- both queues are locked */ while (!queue_empty(&queue_from->head)) { call = TIMER_CALL(queue_first(&queue_from->head)); - if (!simple_lock_try(&call->lock)) { + if (!simple_lock_try(&call->lock, LCK_GRP_NULL)) { /* case (2b) lock order inversion, dequeue only */ #ifdef TIMER_ASSERT - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, - call, - CE(call)->queue, - call->lock.interlock.lock_data, - 0x2b, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + VM_KERNEL_UNSLIDE_OR_PERM(TCE(call)->queue), + VM_KERNEL_UNSLIDE_OR_PERM(call->lock.interlock.lock_data), + 0x2b, 0); #endif timer_queue_migrate_lock_skips++; timer_call_entry_dequeue_async(call); @@ -938,15 +1188,15 @@ timer_queue_migrate(mpqueue_head_t *queue_from, mpqueue_head_t *queue_to) } timer_call_entry_dequeue(call); timer_call_entry_enqueue_deadline( - call, queue_to, CE(call)->deadline); + call, queue_to, TCE(call)->deadline); timers_migrated++; simple_unlock(&call->lock); } queue_from->earliest_soft_deadline = UINT64_MAX; abort2: - timer_queue_unlock(queue_from); + timer_queue_unlock(queue_from); abort1: - timer_queue_unlock(queue_to); + timer_queue_unlock(queue_to); return timers_migrated; } @@ -956,44 +1206,45 @@ timer_queue_trace_cpu(int ncpu) { timer_call_nosync_cpu( ncpu, - (void(*)())timer_queue_trace, + (void (*)(void *))timer_queue_trace, (void*) timer_queue_cpu(ncpu)); } void timer_queue_trace( - mpqueue_head_t *queue) + mpqueue_head_t *queue) { - timer_call_t call; - spl_t s; + timer_call_t call; + spl_t s; - if (!kdebug_enable) + if (!kdebug_enable) { return; + } s = splclock(); timer_queue_lock_spin(queue); TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_QUEUE | DBG_FUNC_START, - queue->count, mach_absolute_time(), 0, 0, 0); + DECR_TIMER_QUEUE | DBG_FUNC_START, + queue->count, mach_absolute_time(), 0, 0, 0); if (!queue_empty(&queue->head)) { call = TIMER_CALL(queue_first(&queue->head)); do { TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_QUEUE | DBG_FUNC_NONE, - call->soft_deadline, - CE(call)->deadline, - CE(call)->entry_time, - CE(call)->func, - 0); + DECR_TIMER_QUEUE | DBG_FUNC_NONE, + call->soft_deadline, + TCE(call)->deadline, + TCE(call)->entry_time, + VM_KERNEL_UNSLIDE(TCE(call)->func), + 0); call = TIMER_CALL(queue_next(qe(call))); } while (!queue_end(&queue->head, qe(call))); } TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_QUEUE | DBG_FUNC_END, - queue->count, mach_absolute_time(), 0, 0, 0); + DECR_TIMER_QUEUE | DBG_FUNC_END, + queue->count, mach_absolute_time(), 0, 0, 0); timer_queue_unlock(queue); splx(s); @@ -1002,11 +1253,12 @@ timer_queue_trace( void timer_longterm_dequeued_locked(timer_call_t call) { - timer_longterm_t *tlp = &timer_longterm; + timer_longterm_t *tlp = &timer_longterm; tlp->dequeues++; - if (call == tlp->threshold.call) + if (call == tlp->threshold.call) { tlp->threshold.call = NULL; + } } /* @@ -1014,14 +1266,18 @@ timer_longterm_dequeued_locked(timer_call_t call) * and adjust the next timer callout deadline if the new timer is first. */ mpqueue_head_t * -timer_longterm_enqueue_unlocked(timer_call_t call, - uint64_t now, - uint64_t deadline, - mpqueue_head_t **old_queue) +timer_longterm_enqueue_unlocked(timer_call_t call, + uint64_t now, + uint64_t deadline, + mpqueue_head_t **old_queue, + uint64_t soft_deadline, + uint64_t ttd, + timer_call_param_t param1, + uint32_t callout_flags) { - timer_longterm_t *tlp = &timer_longterm; - boolean_t update_required = FALSE; - uint64_t longterm_threshold; + timer_longterm_t *tlp = &timer_longterm; + boolean_t update_required = FALSE; + uint64_t longterm_threshold; longterm_threshold = now + tlp->threshold.interval; @@ -1031,13 +1287,14 @@ timer_longterm_enqueue_unlocked(timer_call_t call, * - the longterm mechanism is disabled, or * - this deadline is too short. */ - if (__probable((call->flags & TIMER_CALL_LOCAL) != 0 || + if ((callout_flags & TIMER_CALL_LOCAL) != 0 || (tlp->threshold.interval == TIMER_LONGTERM_NONE) || - (deadline <= longterm_threshold))) + (deadline <= longterm_threshold)) { return NULL; + } /* - * Remove timer from its current queue, if any. + * Remove timer from its current queue, if any. */ *old_queue = timer_call_dequeue_unlocked(call); @@ -1046,17 +1303,21 @@ timer_longterm_enqueue_unlocked(timer_call_t call, * whether an update is necessary. */ assert(!ml_get_interrupts_enabled()); - simple_lock(&call->lock); + simple_lock(&call->lock, LCK_GRP_NULL); timer_queue_lock_spin(timer_longterm_queue); + TCE(call)->deadline = deadline; + TCE(call)->param1 = param1; + call->ttd = ttd; + call->soft_deadline = soft_deadline; + call->flags = callout_flags; timer_call_entry_enqueue_tail(call, timer_longterm_queue); - CE(call)->deadline = deadline; - + tlp->enqueues++; /* * We'll need to update the currently set threshold timer * if the new deadline is sooner and no sooner update is in flight. - */ + */ if (deadline < tlp->threshold.deadline && deadline < tlp->threshold.preempted) { tlp->threshold.preempted = deadline; @@ -1065,11 +1326,15 @@ timer_longterm_enqueue_unlocked(timer_call_t call, } timer_queue_unlock(timer_longterm_queue); simple_unlock(&call->lock); - + if (update_required) { + /* + * Note: this call expects that calling the master cpu + * alone does not involve locking the topo lock. + */ timer_call_nosync_cpu( master_cpu, - (void (*)(void *)) timer_longterm_update, + (void (*)(void *))timer_longterm_update, (void *)tlp); } @@ -1084,33 +1349,37 @@ timer_longterm_enqueue_unlocked(timer_call_t call, * The scan is similar to the timer migrate sequence but is performed by * successively examining each timer on the longterm queue: * - if within the short-term threshold - * - enter on the local queue (unless being deleted), + * - enter on the local queue (unless being deleted), * - otherwise: * - if sooner, deadline becomes the next threshold deadline. + * The total scan time is limited to TIMER_LONGTERM_SCAN_LIMIT. Should this be + * exceeded, we abort and reschedule again so that we don't shut others from + * the timer queues. Longterm timers firing late is not critical. */ void -timer_longterm_scan(timer_longterm_t *tlp, - uint64_t now) +timer_longterm_scan(timer_longterm_t *tlp, + uint64_t time_start) { - queue_entry_t qe; - timer_call_t call; - uint64_t threshold; - uint64_t deadline; - mpqueue_head_t *timer_master_queue; + queue_entry_t qe; + timer_call_t call; + uint64_t threshold; + uint64_t deadline; + uint64_t time_limit = time_start + tlp->scan_limit; + mpqueue_head_t *timer_master_queue; assert(!ml_get_interrupts_enabled()); assert(cpu_number() == master_cpu); - if (tlp->threshold.interval != TIMER_LONGTERM_NONE) - threshold = now + tlp->threshold.interval; - else - threshold = TIMER_LONGTERM_NONE; + if (tlp->threshold.interval != TIMER_LONGTERM_NONE) { + threshold = time_start + tlp->threshold.interval; + } tlp->threshold.deadline = TIMER_LONGTERM_NONE; tlp->threshold.call = NULL; - if (queue_empty(&timer_longterm_queue->head)) + if (queue_empty(&timer_longterm_queue->head)) { return; + } timer_master_queue = timer_queue_cpu(master_cpu); timer_queue_lock_spin(timer_master_queue); @@ -1120,15 +1389,15 @@ timer_longterm_scan(timer_longterm_t *tlp, call = TIMER_CALL(qe); deadline = call->soft_deadline; qe = queue_next(qe); - if (!simple_lock_try(&call->lock)) { + if (!simple_lock_try(&call->lock, LCK_GRP_NULL)) { /* case (2c) lock order inversion, dequeue only */ #ifdef TIMER_ASSERT TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, - call, - CE(call)->queue, - call->lock.interlock.lock_data, - 0x2c, 0); + DECR_TIMER_ASYNC_DEQ | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + VM_KERNEL_UNSLIDE_OR_PERM(TCE(call)->queue), + VM_KERNEL_UNSLIDE_OR_PERM(call->lock.interlock.lock_data), + 0x2c, 0); #endif timer_call_entry_dequeue_async(call); continue; @@ -1139,26 +1408,27 @@ timer_longterm_scan(timer_longterm_t *tlp, * to the local (boot) processor's queue. */ #ifdef TIMER_ASSERT - if (deadline < now) + if (deadline < time_start) { TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_OVERDUE | DBG_FUNC_NONE, - call, - deadline, - now, - threshold, - 0); + DECR_TIMER_OVERDUE | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + deadline, + time_start, + threshold, + 0); + } #endif TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_ESCALATE | DBG_FUNC_NONE, - call, - CE(call)->deadline, - CE(call)->entry_time, - CE(call)->func, - 0); + DECR_TIMER_ESCALATE | DBG_FUNC_NONE, + VM_KERNEL_UNSLIDE_OR_PERM(call), + TCE(call)->deadline, + TCE(call)->entry_time, + VM_KERNEL_UNSLIDE(TCE(call)->func), + 0); tlp->escalates++; timer_call_entry_dequeue(call); timer_call_entry_enqueue_deadline( - call, timer_master_queue, CE(call)->deadline); + call, timer_master_queue, TCE(call)->deadline); /* * A side-effect of the following call is to update * the actual hardware deadline if required. @@ -1171,6 +1441,15 @@ timer_longterm_scan(timer_longterm_t *tlp, } } simple_unlock(&call->lock); + + /* Abort scan if we're taking too long. */ + if (mach_absolute_time() > time_limit) { + tlp->threshold.deadline = TIMER_LONGTERM_SCAN_AGAIN; + tlp->scan_pauses++; + DBG("timer_longterm_scan() paused %llu, qlen: %llu\n", + time_limit, tlp->queue.count); + break; + } } timer_queue_unlock(timer_master_queue); @@ -1179,7 +1458,7 @@ timer_longterm_scan(timer_longterm_t *tlp, void timer_longterm_callout(timer_call_param_t p0, __unused timer_call_param_t p1) { - timer_longterm_t *tlp = (timer_longterm_t *) p0; + timer_longterm_t *tlp = (timer_longterm_t *) p0; timer_longterm_update(tlp); } @@ -1187,14 +1466,14 @@ timer_longterm_callout(timer_call_param_t p0, __unused timer_call_param_t p1) void timer_longterm_update_locked(timer_longterm_t *tlp) { - uint64_t latency; + uint64_t latency; - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_UPDATE | DBG_FUNC_START, - &tlp->queue, - tlp->threshold.deadline, - tlp->threshold.preempted, - tlp->queue.count, 0); + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_UPDATE | DBG_FUNC_START, + VM_KERNEL_UNSLIDE_OR_PERM(&tlp->queue), + tlp->threshold.deadline, + tlp->threshold.preempted, + tlp->queue.count, 0); tlp->scan_time = mach_absolute_time(); if (tlp->threshold.preempted != TIMER_LONGTERM_NONE) { @@ -1213,55 +1492,65 @@ timer_longterm_update_locked(timer_longterm_t *tlp) * Maintain a moving average of our wakeup latency. * Clamp latency to 0 and ignore above threshold interval. */ - if (tlp->scan_time > tlp->threshold.deadline_set) + if (tlp->scan_time > tlp->threshold.deadline_set) { latency = tlp->scan_time - tlp->threshold.deadline_set; - else + } else { latency = 0; + } if (latency < tlp->threshold.interval) { tlp->threshold.latency_min = - MIN(tlp->threshold.latency_min, latency); + MIN(tlp->threshold.latency_min, latency); tlp->threshold.latency_max = - MAX(tlp->threshold.latency_max, latency); + MAX(tlp->threshold.latency_max, latency); tlp->threshold.latency = - (tlp->threshold.latency*99 + latency) / 100; + (tlp->threshold.latency * 99 + latency) / 100; } - timer_longterm_scan(tlp, tlp->scan_time); + timer_longterm_scan(tlp, tlp->scan_time); } tlp->threshold.deadline_set = tlp->threshold.deadline; /* The next deadline timer to be set is adjusted */ - if (tlp->threshold.deadline != TIMER_LONGTERM_NONE) { + if (tlp->threshold.deadline != TIMER_LONGTERM_NONE && + tlp->threshold.deadline != TIMER_LONGTERM_SCAN_AGAIN) { tlp->threshold.deadline_set -= tlp->threshold.margin; tlp->threshold.deadline_set -= tlp->threshold.latency; } - TIMER_KDEBUG_TRACE(KDEBUG_TRACE, - DECR_TIMER_UPDATE | DBG_FUNC_END, - &tlp->queue, - tlp->threshold.deadline, - tlp->threshold.scans, - tlp->queue.count, 0); + /* Throttle next scan time */ + uint64_t scan_clamp = mach_absolute_time() + tlp->scan_interval; + if (tlp->threshold.deadline_set < scan_clamp) { + tlp->threshold.deadline_set = scan_clamp; + } + + TIMER_KDEBUG_TRACE(KDEBUG_TRACE, + DECR_TIMER_UPDATE | DBG_FUNC_END, + VM_KERNEL_UNSLIDE_OR_PERM(&tlp->queue), + tlp->threshold.deadline, + tlp->threshold.scans, + tlp->queue.count, 0); } void timer_longterm_update(timer_longterm_t *tlp) { - spl_t s = splclock(); + spl_t s = splclock(); timer_queue_lock_spin(timer_longterm_queue); - if (cpu_number() != master_cpu) + if (cpu_number() != master_cpu) { panic("timer_longterm_update_master() on non-boot cpu"); + } timer_longterm_update_locked(tlp); - if (tlp->threshold.deadline != TIMER_LONGTERM_NONE) + if (tlp->threshold.deadline != TIMER_LONGTERM_NONE) { timer_call_enter( &tlp->threshold.timer, tlp->threshold.deadline_set, TIMER_CALL_LOCAL | TIMER_CALL_SYS_CRITICAL); - + } + timer_queue_unlock(timer_longterm_queue); splx(s); } @@ -1269,28 +1558,30 @@ timer_longterm_update(timer_longterm_t *tlp) void timer_longterm_init(void) { - uint32_t longterm; - timer_longterm_t *tlp = &timer_longterm; + uint32_t longterm; + timer_longterm_t *tlp = &timer_longterm; DBG("timer_longterm_init() tlp: %p, queue: %p\n", tlp, &tlp->queue); /* - * Set the longterm timer threshold. - * Defaults to TIMER_LONGTERM_THRESHOLD; overridden longterm boot-arg + * Set the longterm timer threshold. Defaults to TIMER_LONGTERM_THRESHOLD + * or TIMER_LONGTERM_NONE (disabled) for server; + * overridden longterm boot-arg */ - tlp->threshold.interval = TIMER_LONGTERM_THRESHOLD; - if (PE_parse_boot_argn("longterm", &longterm, sizeof (longterm))) { + tlp->threshold.interval = serverperfmode ? TIMER_LONGTERM_NONE + : TIMER_LONGTERM_THRESHOLD; + if (PE_parse_boot_argn("longterm", &longterm, sizeof(longterm))) { tlp->threshold.interval = (longterm == 0) ? - TIMER_LONGTERM_NONE : - longterm * NSEC_PER_MSEC; + TIMER_LONGTERM_NONE : + longterm * NSEC_PER_MSEC; } if (tlp->threshold.interval != TIMER_LONGTERM_NONE) { printf("Longterm timer threshold: %llu ms\n", - tlp->threshold.interval / NSEC_PER_MSEC); + tlp->threshold.interval / NSEC_PER_MSEC); kprintf("Longterm timer threshold: %llu ms\n", - tlp->threshold.interval / NSEC_PER_MSEC); + tlp->threshold.interval / NSEC_PER_MSEC); nanoseconds_to_absolutetime(tlp->threshold.interval, - &tlp->threshold.interval); + &tlp->threshold.interval); tlp->threshold.margin = tlp->threshold.interval / 10; tlp->threshold.latency_min = EndOfAllTime; tlp->threshold.latency_max = 0; @@ -1302,12 +1593,12 @@ timer_longterm_init(void) lck_attr_setdefault(&timer_longterm_lck_attr); lck_grp_attr_setdefault(&timer_longterm_lck_grp_attr); lck_grp_init(&timer_longterm_lck_grp, - "timer_longterm", &timer_longterm_lck_grp_attr); + "timer_longterm", &timer_longterm_lck_grp_attr); mpqueue_init(&tlp->queue, - &timer_longterm_lck_grp, &timer_longterm_lck_attr); + &timer_longterm_lck_grp, &timer_longterm_lck_attr); timer_call_setup(&tlp->threshold.timer, - timer_longterm_callout, (timer_call_param_t) tlp); + timer_longterm_callout, (timer_call_param_t) tlp); timer_longterm_queue = &tlp->queue; } @@ -1315,17 +1606,17 @@ timer_longterm_init(void) enum { THRESHOLD, QCOUNT, ENQUEUES, DEQUEUES, ESCALATES, SCANS, PREEMPTS, - LATENCY, LATENCY_MIN, LATENCY_MAX + LATENCY, LATENCY_MIN, LATENCY_MAX, SCAN_LIMIT, SCAN_INTERVAL, PAUSES }; uint64_t timer_sysctl_get(int oid) { - timer_longterm_t *tlp = &timer_longterm; + timer_longterm_t *tlp = &timer_longterm; switch (oid) { case THRESHOLD: return (tlp->threshold.interval == TIMER_LONGTERM_NONE) ? - 0 : tlp->threshold.interval / NSEC_PER_MSEC; + 0 : tlp->threshold.interval / NSEC_PER_MSEC; case QCOUNT: return tlp->queue.count; case ENQUEUES: @@ -1344,6 +1635,12 @@ timer_sysctl_get(int oid) return tlp->threshold.latency_min; case LATENCY_MAX: return tlp->threshold.latency_max; + case SCAN_LIMIT: + return tlp->scan_limit; + case SCAN_INTERVAL: + return tlp->scan_interval; + case PAUSES: + return tlp->scan_pauses; default: return 0; } @@ -1354,19 +1651,20 @@ timer_sysctl_get(int oid) * since it un-escalates timers to the longterm queue. */ static void -timer_master_scan(timer_longterm_t *tlp, - uint64_t now) +timer_master_scan(timer_longterm_t *tlp, + uint64_t now) { - queue_entry_t qe; - timer_call_t call; - uint64_t threshold; - uint64_t deadline; - mpqueue_head_t *timer_master_queue; + queue_entry_t qe; + timer_call_t call; + uint64_t threshold; + uint64_t deadline; + mpqueue_head_t *timer_master_queue; - if (tlp->threshold.interval != TIMER_LONGTERM_NONE) + if (tlp->threshold.interval != TIMER_LONGTERM_NONE) { threshold = now + tlp->threshold.interval; - else + } else { threshold = TIMER_LONGTERM_NONE; + } timer_master_queue = timer_queue_cpu(master_cpu); timer_queue_lock_spin(timer_master_queue); @@ -1374,11 +1672,12 @@ timer_master_scan(timer_longterm_t *tlp, qe = queue_first(&timer_master_queue->head); while (!queue_end(&timer_master_queue->head, qe)) { call = TIMER_CALL(qe); - deadline = CE(call)->deadline; + deadline = TCE(call)->deadline; qe = queue_next(qe); - if ((call->flags & TIMER_CALL_LOCAL) != 0) + if ((call->flags & TIMER_CALL_LOCAL) != 0) { continue; - if (!simple_lock_try(&call->lock)) { + } + if (!simple_lock_try(&call->lock, LCK_GRP_NULL)) { /* case (2c) lock order inversion, dequeue only */ timer_call_entry_dequeue_async(call); continue; @@ -1400,9 +1699,9 @@ timer_master_scan(timer_longterm_t *tlp, static void timer_sysctl_set_threshold(uint64_t value) { - timer_longterm_t *tlp = &timer_longterm; - spl_t s = splclock(); - boolean_t threshold_increase; + timer_longterm_t *tlp = &timer_longterm; + spl_t s = splclock(); + boolean_t threshold_increase; timer_queue_lock_spin(timer_longterm_queue); @@ -1416,21 +1715,22 @@ timer_sysctl_set_threshold(uint64_t value) threshold_increase = TRUE; timer_call_cancel(&tlp->threshold.timer); } else { - uint64_t old_interval = tlp->threshold.interval; + uint64_t old_interval = tlp->threshold.interval; tlp->threshold.interval = value * NSEC_PER_MSEC; nanoseconds_to_absolutetime(tlp->threshold.interval, - &tlp->threshold.interval); + &tlp->threshold.interval); tlp->threshold.margin = tlp->threshold.interval / 10; - if (old_interval == TIMER_LONGTERM_NONE) + if (old_interval == TIMER_LONGTERM_NONE) { threshold_increase = FALSE; - else + } else { threshold_increase = (tlp->threshold.interval > old_interval); + } } if (threshold_increase /* or removal */) { /* Escalate timers from the longterm queue */ timer_longterm_scan(tlp, mach_absolute_time()); - } else /* decrease or addition */ { + } else { /* decrease or addition */ /* * We scan the local/master queue for timers now longterm. * To be strictly correct, we should scan all processor queues @@ -1455,6 +1755,7 @@ timer_sysctl_set_threshold(uint64_t value) tlp->enqueues = 0; tlp->dequeues = 0; tlp->escalates = 0; + tlp->scan_pauses = 0; tlp->threshold.scans = 0; tlp->threshold.preempts = 0; tlp->threshold.latency = 0; @@ -1472,10 +1773,155 @@ timer_sysctl_set(int oid, uint64_t value) case THRESHOLD: timer_call_cpu( master_cpu, - (void (*)(void *)) timer_sysctl_set_threshold, + (void (*)(void *))timer_sysctl_set_threshold, (void *) value); return KERN_SUCCESS; + case SCAN_LIMIT: + timer_longterm.scan_limit = value; + return KERN_SUCCESS; + case SCAN_INTERVAL: + timer_longterm.scan_interval = value; + return KERN_SUCCESS; default: return KERN_INVALID_ARGUMENT; } } + + +/* Select timer coalescing window based on per-task quality-of-service hints */ +static boolean_t +tcoal_qos_adjust(thread_t t, int32_t *tshift, uint64_t *tmax_abstime, boolean_t *pratelimited) +{ + uint32_t latency_qos; + boolean_t adjusted = FALSE; + task_t ctask = t->task; + + if (ctask) { + latency_qos = proc_get_effective_thread_policy(t, TASK_POLICY_LATENCY_QOS); + + assert(latency_qos <= NUM_LATENCY_QOS_TIERS); + + if (latency_qos) { + *tshift = tcoal_prio_params.latency_qos_scale[latency_qos - 1]; + *tmax_abstime = tcoal_prio_params.latency_qos_abstime_max[latency_qos - 1]; + *pratelimited = tcoal_prio_params.latency_tier_rate_limited[latency_qos - 1]; + adjusted = TRUE; + } + } + return adjusted; +} + + +/* Adjust timer deadlines based on priority of the thread and the + * urgency value provided at timeout establishment. With this mechanism, + * timers are no longer necessarily sorted in order of soft deadline + * on a given timer queue, i.e. they may be differentially skewed. + * In the current scheme, this could lead to fewer pending timers + * processed than is technically possible when the HW deadline arrives. + */ +static void +timer_compute_leeway(thread_t cthread, int32_t urgency, int32_t *tshift, uint64_t *tmax_abstime, boolean_t *pratelimited) +{ + int16_t tpri = cthread->sched_pri; + if ((urgency & TIMER_CALL_USER_MASK) != 0) { + if (tpri >= BASEPRI_RTQUEUES || + urgency == TIMER_CALL_USER_CRITICAL) { + *tshift = tcoal_prio_params.timer_coalesce_rt_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_rt_abstime_max; + TCOAL_PRIO_STAT(rt_tcl); + } else if (proc_get_effective_thread_policy(cthread, TASK_POLICY_DARWIN_BG) || + (urgency == TIMER_CALL_USER_BACKGROUND)) { + /* Determine if timer should be subjected to a lower QoS */ + if (tcoal_qos_adjust(cthread, tshift, tmax_abstime, pratelimited)) { + if (*tmax_abstime > tcoal_prio_params.timer_coalesce_bg_abstime_max) { + return; + } else { + *pratelimited = FALSE; + } + } + *tshift = tcoal_prio_params.timer_coalesce_bg_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_bg_abstime_max; + TCOAL_PRIO_STAT(bg_tcl); + } else if (tpri >= MINPRI_KERNEL) { + *tshift = tcoal_prio_params.timer_coalesce_kt_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_kt_abstime_max; + TCOAL_PRIO_STAT(kt_tcl); + } else if (cthread->sched_mode == TH_MODE_FIXED) { + *tshift = tcoal_prio_params.timer_coalesce_fp_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_fp_abstime_max; + TCOAL_PRIO_STAT(fp_tcl); + } else if (tcoal_qos_adjust(cthread, tshift, tmax_abstime, pratelimited)) { + TCOAL_PRIO_STAT(qos_tcl); + } else if (cthread->sched_mode == TH_MODE_TIMESHARE) { + *tshift = tcoal_prio_params.timer_coalesce_ts_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_ts_abstime_max; + TCOAL_PRIO_STAT(ts_tcl); + } else { + TCOAL_PRIO_STAT(nc_tcl); + } + } else if (urgency == TIMER_CALL_SYS_BACKGROUND) { + *tshift = tcoal_prio_params.timer_coalesce_bg_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_bg_abstime_max; + TCOAL_PRIO_STAT(bg_tcl); + } else { + *tshift = tcoal_prio_params.timer_coalesce_kt_shift; + *tmax_abstime = tcoal_prio_params.timer_coalesce_kt_abstime_max; + TCOAL_PRIO_STAT(kt_tcl); + } +} + + +int timer_user_idle_level; + +uint64_t +timer_call_slop(uint64_t deadline, uint64_t now, uint32_t flags, thread_t cthread, boolean_t *pratelimited) +{ + int32_t tcs_shift = 0; + uint64_t tcs_max_abstime = 0; + uint64_t adjval; + uint32_t urgency = (flags & TIMER_CALL_URGENCY_MASK); + + if (mach_timer_coalescing_enabled && + (deadline > now) && (urgency != TIMER_CALL_SYS_CRITICAL)) { + timer_compute_leeway(cthread, urgency, &tcs_shift, &tcs_max_abstime, pratelimited); + + if (tcs_shift >= 0) { + adjval = MIN((deadline - now) >> tcs_shift, tcs_max_abstime); + } else { + adjval = MIN((deadline - now) << (-tcs_shift), tcs_max_abstime); + } + /* Apply adjustments derived from "user idle level" heuristic */ + adjval += (adjval * timer_user_idle_level) >> 7; + return adjval; + } else { + return 0; + } +} + +int +timer_get_user_idle_level(void) +{ + return timer_user_idle_level; +} + +kern_return_t +timer_set_user_idle_level(int ilevel) +{ + boolean_t do_reeval = FALSE; + + if ((ilevel < 0) || (ilevel > 128)) { + return KERN_INVALID_ARGUMENT; + } + + if (ilevel < timer_user_idle_level) { + do_reeval = TRUE; + } + + timer_user_idle_level = ilevel; + + if (do_reeval) { + ml_timer_evaluate(); + } + + return KERN_SUCCESS; +}