Wed Aug 20 16:05:19 1997 Thomas Bushnell, n/BSG <thomas@gnu.ai.mit.edu>

	* kern/thread.h (struct thread): New member `creation_time'.
	* include/mach/thread_info.h: New member `creation_time'.
	* kern/thread.c (thread_create): Set creation time stamp.
	(thread_info) [THREAD_BASIC_INFO]: Fill in new creation time
	field.  Carefully preserve compatibility with old callers.

	* kern/task.h (struct task): New member `creation_time'.
	* include/mach/task_info.h: New member `creation_time'.
	* kern/task.c (task_create): Set creation time stamp.
	(task_info) [TASK_BASIC_INFO]: Fill in new creation time field.
	Carefully preserve compatibility with old callers.

	* kern/mach_clock.c (record_time_stamp): New function.
	* kern/time_out.h (record_time_stamp): Add prototype.

6 files changed, 41 insertions, 4 deletions

diff --git a/kern/mach_clock.c b/kern/mach_clock.c
index 9076ef4..ee9896a 100644
--- a/kern/mach_clock.c
+++ b/kern/mach_clock.c
@@ -369,6 +369,19 @@ void init_timeout()
 }
 
 /*
+ * Record a timestamp in STAMP. 
+ */
+void
+record_time_stamp (time_value_t *stamp)
+{
+	do {
+		stamp->seconds = mtime->seconds;
+		stamp->microseconds = mtime->microseconds;
+	} while (stamp->seconds != mtime->check_seconds);
+}
+
+
+/*
  * Read the time.
  */
 kern_return_t
diff --git a/kern/task.c b/kern/task.c
index f72bb0f..9302e6a 100644
--- a/kern/task.c
+++ b/kern/task.c
@@ -166,6 +166,8 @@ kern_return_t task_create(
 	new_task->total_system_time.seconds = 0;
 	new_task->total_system_time.microseconds = 0;
 
+	record_time_stamp (&new_task->creation_time);
+
 	if (parent_task != TASK_NULL) {
 		task_lock(parent_task);
 		pset = parent_task->processor_set;
@@ -774,7 +776,11 @@ kern_return_t task_info(
 	    {
 		register task_basic_info_t	basic_info;
 
-		if (*task_info_count < TASK_BASIC_INFO_COUNT) {
+		/* Allow *task_info_count to be one smaller than
+		   the usual amount, because creation_time is a new member
+		   that some callers might not know about. */
+		  
+		if (*task_info_count < TASK_BASIC_INFO_COUNT - 1) {
 		    return KERN_INVALID_ARGUMENT;
 		}
 
@@ -797,9 +803,11 @@ kern_return_t task_info(
 				= task->total_system_time.seconds;
 		basic_info->system_time.microseconds 
 				= task->total_system_time.microseconds;
+		basic_info->creation_time = task->creation_time;
 		task_unlock(task);
 
-		*task_info_count = TASK_BASIC_INFO_COUNT;
+		if (*task_info_count > TASK_BASIC_INFO_COUNT)
+		  *task_info_count = TASK_BASIC_INFO_COUNT;
 		break;
 	    }
 
diff --git a/kern/task.h b/kern/task.h
index 52733b9..ec80058 100644
--- a/kern/task.h
+++ b/kern/task.h
@@ -86,6 +86,8 @@ struct task {
 	time_value_t	total_system_time;
 				/* total system time for dead threads */
 
+	time_value_t	creation_time; /* time stamp at creation */
+
 	/* IPC structures */
 	decl_simple_lock_data(, itk_lock_data)
 	struct ipc_port *itk_self;	/* not a right, doesn't hold ref */
diff --git a/kern/thread.c b/kern/thread.c
index 1d7a378..d186298 100644
--- a/kern/thread.c
+++ b/kern/thread.c
@@ -429,6 +429,8 @@ kern_return_t thread_create(
 
 	*new_thread = thread_template;
 
+	record_time_stamp (&new_thread->creation_time);
+
 	/*
 	 *	Initialize runtime-dependent fields
 	 */
@@ -1473,7 +1475,11 @@ kern_return_t thread_info(
 	if (flavor == THREAD_BASIC_INFO) {
 	    register thread_basic_info_t	basic_info;
 
-	    if (*thread_info_count < THREAD_BASIC_INFO_COUNT) {
+	    /* Allow *thread_info_count to be one smaller than the
+	       usual amount, because creation_time is a new member
+	       that some callers might not know about. */
+
+	    if (*thread_info_count < THREAD_BASIC_INFO_COUNT - 1) {
 		return KERN_INVALID_ARGUMENT;
 	    }
 
@@ -1496,6 +1502,7 @@ kern_return_t thread_info(
 			&basic_info->system_time);
 	    basic_info->base_priority	= thread->priority;
 	    basic_info->cur_priority	= thread->sched_pri;
+	    basic_info->creation_time  = thread->creation_time;
 
 	    /*
 	     *	To calculate cpu_usage, first correct for timer rate,
@@ -1547,7 +1554,8 @@ kern_return_t thread_info(
 	    thread_unlock(thread);
 	    splx(s);
 
-	    *thread_info_count = THREAD_BASIC_INFO_COUNT;
+	    if (*thread_info_count > THREAD_BASIC_INFO_COUNT)
+	      *thread_info_count = THREAD_BASIC_INFO_COUNT;
 	    return KERN_SUCCESS;
 	}
 	else if (flavor == THREAD_SCHED_INFO) {
diff --git a/kern/thread.h b/kern/thread.h
index 07b7463..9958e2b 100644
--- a/kern/thread.h
+++ b/kern/thread.h
@@ -195,6 +195,9 @@ struct thread {
 	unsigned int	cpu_delta;	/* cpu usage since last update */
 	unsigned int	sched_delta;	/* weighted cpu usage since update */
 
+	/* Creation time stamp */
+	time_value_t	creation_time;
+
 	/* Time-outs */
 	timer_elt_data_t timer;		/* timer for thread */
 	timer_elt_data_t depress_timer;	/* timer for priority depression */
diff --git a/kern/time_out.h b/kern/time_out.h
index 4dff7df..5fbf4e3 100644
--- a/kern/time_out.h
+++ b/kern/time_out.h
@@ -43,6 +43,9 @@ extern unsigned long elapsed_ticks; /* number of ticks elapsed since bootup */
 extern int	hz;		/* number of ticks per second */
 extern int	tick;		/* number of usec per tick */
 
+/* Read the current time into STAMP */
+void record_time_stamp (time_value_t *stamp);
+
 /*
  *	Time-out element.
  */