* Increased the maximum profiling caller stack depth significantly.

* Extended the profiling API by an option to record a variable number of
  samples per tick. The stack depth is used as a maximum.
* Added new option "-f" to the "profile" tool. When specified it
  increments the hit counts of all symbols in the full available caller
  stack. I.e. the resulting hit counts will approximate the total time
  spent in each function or any function directly or indirectly called
  by it. Thus "_start" and "main" will usually get 100% and leaf
  functions only what time has actually been spent in them.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27699 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/user_debugger.h

@@ -16,7 +16,7 @@
 
 // limits
 #define B_DEBUG_MIN_PROFILE_INTERVAL			10			/* in us */
-#define B_DEBUG_STACK_TRACE_DEPTH				20
+#define B_DEBUG_STACK_TRACE_DEPTH				128
 #define	B_DEBUG_PROFILE_BUFFER_FLUSH_THRESHOLD	70			/* in % */
 
 
@@ -96,6 +96,8 @@ struct thread_debug_info {
 		int32			image_event;
 			// number of the image event when the first sample was written into
 			// the buffer
+		bool			variable_stack_depth;
+			// record a variable number of samples per hit
 		bool			buffer_full;
 			// indicates that the sample buffer is full
 		union {