PERFORCE change 131409 for review

[John Birrell]

http://perforce.freebsd.org/chv.cgi?CH=131409

Change 131409 by jb at jb_freebsd1 on 2007/12/22 04:32:34

	Add the cyclic timer hook.

Affected files ...

.. //depot/projects/dtrace/src/sys/amd64/amd64/local_apic.c#11 edit

Differences ...

==== //depot/projects/dtrace/src/sys/amd64/amd64/local_apic.c#11 (text+ko) ====

@@ -35,6 +35,7 @@
 __FBSDID("$FreeBSD: src/sys/amd64/amd64/local_apic.c,v 1.43 2007/10/27 13:34:53 jhb Exp $");
 
 #include "opt_hwpmc_hooks.h"
+#include "opt_kdtrace.h"
 
 #include "opt_ddb.h"
 
@@ -65,6 +66,11 @@
 #include <ddb/ddb.h>
 #endif
 
+#ifdef KDTRACE_HOOKS
+#include <sys/dtrace_bsd.h>
+cyclic_clock_func_t	lapic_cyclic_clock_func;
+#endif
+
 /* Sanity checks on IDT vectors. */
 CTASSERT(APIC_IO_INTS + APIC_NUM_IOINTS == APIC_TIMER_INT);
 CTASSERT(APIC_TIMER_INT < APIC_LOCAL_INTS);
@@ -676,6 +682,19 @@
 			hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
 		else
 			hardclock_cpu(TRAPF_USERMODE(frame));
+
+#ifdef KDTRACE_HOOKS
+		/*
+		 * If the DTrace hooks are configured and a callback
+		 * function has been registered, then call it to process
+		 * the high speed timers. If this function is registered
+		 * here, then there mustn't be a High Performance Event
+		 * Timer (HPET) on the CPU. A HPET provides higher
+		 * performance timer interrupts.
+		 */
+		if (lapic_cyclic_clock_func != NULL)
+			(*lapic_cyclic_clock_func)();
+#endif
 	}
 
 	/* Fire statclock at stathz. */