X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/b7266188b87f3620ec3f9f717e57194a7dd989fe..15129b1c8dbb3650c63b70adb1cad9af601c6c17:/osfmk/kern/processor.c

diff --git a/osfmk/kern/processor.c b/osfmk/kern/processor.c
index ca65ceca6..709019b9f 100644
--- a/osfmk/kern/processor.c
+++ b/osfmk/kern/processor.c
@@ -89,7 +89,9 @@ struct pset_node		pset_node0;
 decl_simple_lock_data(static,pset_node_lock)
 
 queue_head_t			tasks;
+queue_head_t			terminated_tasks;	/* To be used ONLY for stackshot. */
 int						tasks_count;
+int						terminated_tasks_count;
 queue_head_t			threads;
 int						threads_count;
 decl_lck_mtx_data(,tasks_threads_lock)
@@ -103,6 +105,7 @@ uint32_t				processor_avail_count;
 
 processor_t		master_processor;
 int 			master_cpu = 0;
+boolean_t		sched_stats_active = FALSE;
 
 /* Forwards */
 kern_return_t	processor_set_things(
@@ -120,6 +123,7 @@ processor_bootstrap(void)
 	simple_lock_init(&pset_node_lock, 0);
 
 	queue_init(&tasks);
+	queue_init(&terminated_tasks);
 	queue_init(&threads);
 
 	simple_lock_init(&processor_list_lock, 0);
@@ -140,12 +144,18 @@ processor_init(
 	int					cpu_id,
 	processor_set_t		pset)
 {
-	run_queue_init(&processor->runq);
+	spl_t		s;
+
+	if (processor != master_processor) {
+		/* Scheduler state deferred until sched_init() */
+		SCHED(processor_init)(processor);
+	}
 
 	processor->state = PROCESSOR_OFF_LINE;
 	processor->active_thread = processor->next_thread = processor->idle_thread = THREAD_NULL;
 	processor->processor_set = pset;
 	processor->current_pri = MINPRI;
+	processor->current_thmode = TH_MODE_NONE;
 	processor->cpu_id = cpu_id;
 	timer_call_setup(&processor->quantum_timer, thread_quantum_expire, processor);
 	processor->deadline = UINT64_MAX;
@@ -155,6 +165,7 @@ processor_init(
 	processor_data_init(processor);
 	processor->processor_list = NULL;
 
+	s = splsched();
 	pset_lock(pset);
 	if (pset->cpu_set_count++ == 0)
 		pset->cpu_set_low = pset->cpu_set_hi = cpu_id;
@@ -163,6 +174,7 @@ processor_init(
 		pset->cpu_set_hi = (cpu_id > pset->cpu_set_hi)? cpu_id: pset->cpu_set_hi;
 	}
 	pset_unlock(pset);
+	splx(s);
 
 	simple_lock(&processor_list_lock);
 	if (processor_list == NULL)
@@ -236,12 +248,19 @@ pset_init(
 	processor_set_t		pset,
 	pset_node_t			node)
 {
+	if (pset != &pset0) {
+		/* Scheduler state deferred until sched_init() */
+		SCHED(pset_init)(pset);
+	}
+
 	queue_init(&pset->active_queue);
 	queue_init(&pset->idle_queue);
-	pset->processor_count = 0;
-	pset->low_pri = pset->low_count = PROCESSOR_NULL;
+	pset->online_processor_count = 0;
+	pset_pri_init_hint(pset, PROCESSOR_NULL);
+	pset_count_init_hint(pset, PROCESSOR_NULL);
 	pset->cpu_set_low = pset->cpu_set_hi = 0;
 	pset->cpu_set_count = 0;
+	pset->pending_AST_cpu_mask = 0;
 	pset_lock_init(pset);
 	pset->pset_self = IP_NULL;
 	pset->pset_name_self = IP_NULL;
@@ -319,18 +338,71 @@ processor_info(
 
 	case PROCESSOR_CPU_LOAD_INFO:
 	{
-		register processor_cpu_load_info_t	cpu_load_info;
-
-	    if (*count < PROCESSOR_CPU_LOAD_INFO_COUNT)
+		processor_cpu_load_info_t	cpu_load_info;
+		timer_t		idle_state;
+		uint64_t	idle_time_snapshot1, idle_time_snapshot2;
+		uint64_t	idle_time_tstamp1, idle_time_tstamp2;
+
+		/*
+		 * We capture the accumulated idle time twice over
+		 * the course of this function, as well as the timestamps
+		 * when each were last updated. Since these are
+		 * all done using non-atomic racy mechanisms, the
+		 * most we can infer is whether values are stable.
+		 * timer_grab() is the only function that can be
+		 * used reliably on another processor's per-processor
+		 * data.
+		 */
+
+		if (*count < PROCESSOR_CPU_LOAD_INFO_COUNT)
 			return (KERN_FAILURE);
 
-	    cpu_load_info = (processor_cpu_load_info_t) info;
-		cpu_load_info->cpu_ticks[CPU_STATE_USER] =
+		cpu_load_info = (processor_cpu_load_info_t) info;
+		if (precise_user_kernel_time) {
+			cpu_load_info->cpu_ticks[CPU_STATE_USER] =
 							(uint32_t)(timer_grab(&PROCESSOR_DATA(processor, user_state)) / hz_tick_interval);
-		cpu_load_info->cpu_ticks[CPU_STATE_SYSTEM] =
+			cpu_load_info->cpu_ticks[CPU_STATE_SYSTEM] =
 							(uint32_t)(timer_grab(&PROCESSOR_DATA(processor, system_state)) / hz_tick_interval);
-		cpu_load_info->cpu_ticks[CPU_STATE_IDLE] =
-							(uint32_t)(timer_grab(&PROCESSOR_DATA(processor, idle_state)) / hz_tick_interval);
+		} else {
+			uint64_t tval = timer_grab(&PROCESSOR_DATA(processor, user_state)) +
+				timer_grab(&PROCESSOR_DATA(processor, system_state));
+
+			cpu_load_info->cpu_ticks[CPU_STATE_USER] = (uint32_t)(tval / hz_tick_interval);
+			cpu_load_info->cpu_ticks[CPU_STATE_SYSTEM] = 0;
+		}
+
+		idle_state = &PROCESSOR_DATA(processor, idle_state);
+		idle_time_snapshot1 = timer_grab(idle_state);
+		idle_time_tstamp1 = idle_state->tstamp;
+
+		/*
+		 * Idle processors are not continually updating their
+		 * per-processor idle timer, so it may be extremely
+		 * out of date, resulting in an over-representation
+		 * of non-idle time between two measurement
+		 * intervals by e.g. top(1). If we are non-idle, or
+		 * have evidence that the timer is being updated
+		 * concurrently, we consider its value up-to-date.
+		 */
+		if (PROCESSOR_DATA(processor, current_state) != idle_state) {
+			cpu_load_info->cpu_ticks[CPU_STATE_IDLE] =
+							(uint32_t)(idle_time_snapshot1 / hz_tick_interval);
+		} else if ((idle_time_snapshot1 != (idle_time_snapshot2 = timer_grab(idle_state))) ||
+				   (idle_time_tstamp1 != (idle_time_tstamp2 = idle_state->tstamp))){
+			/* Idle timer is being updated concurrently, second stamp is good enough */
+			cpu_load_info->cpu_ticks[CPU_STATE_IDLE] =
+							(uint32_t)(idle_time_snapshot2 / hz_tick_interval);
+		} else {
+			/*
+			 * Idle timer may be very stale. Fortunately we have established
+			 * that idle_time_snapshot1 and idle_time_tstamp1 are unchanging
+			 */
+			idle_time_snapshot1 += mach_absolute_time() - idle_time_tstamp1;
+				
+			cpu_load_info->cpu_ticks[CPU_STATE_IDLE] =
+				(uint32_t)(idle_time_snapshot1 / hz_tick_interval);
+		}
+
 		cpu_load_info->cpu_ticks[CPU_STATE_NICE] = 0;
 
 	    *count = PROCESSOR_CPU_LOAD_INFO_COUNT;
@@ -496,6 +568,9 @@ processor_get_assignment(
 {
 	int state;
 
+	if (processor == PROCESSOR_NULL)
+		return(KERN_INVALID_ARGUMENT);
+
 	state = processor->state;
 	if (state == PROCESSOR_SHUTDOWN || state == PROCESSOR_OFF_LINE)
 		return(KERN_FAILURE);
@@ -912,15 +987,6 @@ processor_set_threads(
 {
     return KERN_FAILURE;
 }
-#elif defined(CONFIG_EMBEDDED)
-kern_return_t
-processor_set_threads(
-	__unused processor_set_t		pset,
-	__unused thread_array_t		*thread_list,
-	__unused mach_msg_type_number_t	*count)
-{
-    return KERN_NOT_SUPPORTED;
-}
 #else
 kern_return_t
 processor_set_threads(