PERFORCE change 92932 for review

[John Baldwin]

http://perforce.freebsd.org/chv.cgi?CH=92932

Change 92932 by jhb at jhb_twclab on 2006/03/07 19:45:31

	Don't try to catch rollovers during clock ticks.  This seems
	to be unnecessary in practice (though sadly it means we are
	doing a lot of context switches, even when sitting idle in
	single user).

Affected files ...

.. //depot/projects/smpng/sys/alpha/alpha/clock.c#25 edit
.. //depot/projects/smpng/sys/alpha/alpha/interrupt.c#39 edit
.. //depot/projects/smpng/sys/alpha/include/md_var.h#10 edit
.. //depot/projects/smpng/sys/kern/kern_tc.c#36 edit

Differences ...

==== //depot/projects/smpng/sys/alpha/alpha/clock.c#25 (text+ko) ====

@@ -137,6 +137,7 @@
 static void calibrate_clocks(u_int32_t firmware_freq, u_int32_t *pcc,
     u_int32_t *timer);
 static void set_timer_freq(u_int freq, int intr_freq);
+static uint64_t read_cycle_count(void);
 
 void
 clockattach(device_t dev)

==== //depot/projects/smpng/sys/alpha/alpha/interrupt.c#39 (text+ko) ====

@@ -483,9 +483,6 @@
 #endif
 	if (platform.clockintr) {
 		critical_enter();
-
-		/* Check for PCC roll-over. */
-		(void)read_cycle_count();
 #ifdef SMP
 		/*
 		 * Only one processor drives the actual timer.

==== //depot/projects/smpng/sys/alpha/include/md_var.h#10 (text+ko) ====

@@ -84,7 +84,6 @@
 int	is_physical_memory(vm_offset_t addr);
 void	machine_check(unsigned long, struct trapframe *, unsigned long,
 	    unsigned long);
-uint64_t read_cycle_count(void);
 void	regdump(struct trapframe *);
 void	regtoframe(struct reg *, struct trapframe *);
 void	set_iointr(void (*)(void *, unsigned long));

==== //depot/projects/smpng/sys/kern/kern_tc.c#36 (text+ko) ====

@@ -115,7 +115,6 @@
 
 #undef TC_STATS
 
-static uint64_t tc_cpu_ticks(void);
 static void tc_windup(void);
 static void cpu_tick_calibrate(int);
 
@@ -760,7 +759,6 @@
 		return;
 	count = 0;
 	tc_windup();
-	(void)tc_cpu_ticks();
 	if (time_uptime != last_calib && !(time_uptime & 0xf)) {
 		cpu_tick_calibrate(0);
 		last_calib = time_uptime;