Added args to lock() and unlock() to tell them apart, for use

when lock timing is enabled in minix/config.h.

Added phys_zero() routine to klib386.s that zeroes a range of memory, and
added corresponding system call.

kernel/system/debugging.c

@@ -7,6 +7,102 @@
 #include "../kernel.h"
 #include "../system.h"
 #include "../proc.h"
+#include "../glo.h"
+#include <limits.h>
+
+#if ENABLE_LOCK_TIMING
+
+static unsigned long starttimes[TIMING_CATEGORIES][2];
+
+#define HIGHCOUNT	0
+#define LOWCOUNT	1
+
+void timer_start(int cat, char *name)
+{
+	static int init = 0;
+	unsigned long h, l;
+	int i;
+
+	if(cat < 0 || cat >= TIMING_CATEGORIES) return;
+
+	for(i = 0; i < sizeof(timingdata[0].names) && *name; i++)
+		timingdata[cat].names[i] = *name++;
+	timingdata[0].names[sizeof(timingdata[0].names)-1] = '\0';
+
+	if(starttimes[cat][HIGHCOUNT]) {  return; }
+
+	if(!init) {
+		int t, f;
+		init = 1;
+		for(t = 0; t < TIMING_CATEGORIES; t++) {
+			timingdata[t].lock_timings_range[0] = 0;
+			timingdata[t].resets = timingdata[t].misses = 
+				timingdata[t].measurements = 0;
+		}
+	}
+
+	read_tsc(&starttimes[cat][HIGHCOUNT], &starttimes[cat][LOWCOUNT]);
+
+	return;
+}
+
+void timer_end(int cat)
+{
+	unsigned long h, l, d = 0, binsize;
+	int bin;
+
+	read_tsc(&h, &l);
+	if(cat < 0 || cat >= TIMING_CATEGORIES) return;
+	if(!starttimes[cat][HIGHCOUNT]) {
+		timingdata[cat].misses++;
+		return;
+	}
+	if(starttimes[cat][HIGHCOUNT] == h) {
+		d = (l - starttimes[cat][1]);
+	} else if(starttimes[cat][HIGHCOUNT] == h-1 &&
+		starttimes[cat][LOWCOUNT] > l) {
+		d = ((ULONG_MAX - starttimes[cat][LOWCOUNT]) + l);
+	} else {
+		timingdata[cat].misses++;
+		return;
+	}
+	starttimes[cat][HIGHCOUNT] = 0;
+	if(!timingdata[cat].lock_timings_range[0] ||
+		d < timingdata[cat].lock_timings_range[0] ||
+		d > timingdata[cat].lock_timings_range[1]) {
+		int t;
+		if(!timingdata[cat].lock_timings_range[0] ||
+			d < timingdata[cat].lock_timings_range[0])
+			timingdata[cat].lock_timings_range[0] = d;
+		if(!timingdata[cat].lock_timings_range[1] ||
+			d > timingdata[cat].lock_timings_range[1])
+			timingdata[cat].lock_timings_range[1] = d;
+		for(t = 0; t < TIMING_POINTS; t++)
+			timingdata[cat].lock_timings[t] = 0;
+		timingdata[cat].binsize =
+			(timingdata[cat].lock_timings_range[1] -
+			timingdata[cat].lock_timings_range[0])/(TIMING_POINTS+1);
+		if(timingdata[cat].binsize < 1)
+		  timingdata[cat].binsize = 1;
+		timingdata[cat].resets++;
+	}
+	bin = (d-timingdata[cat].lock_timings_range[0]) /
+		timingdata[cat].binsize;
+	if(bin < 0 || bin >= TIMING_POINTS) {
+		int t;
+		/* this indicates a bug, but isn't really serious */
+		for(t = 0; t < TIMING_POINTS; t++)
+			timingdata[cat].lock_timings[t] = 0;
+		timingdata[cat].misses++;
+	} else {
+		timingdata[cat].lock_timings[bin]++;
+		timingdata[cat].measurements++;
+	}
+
+	return;
+}
+
+#endif
 
 #if ENABLE_K_DEBUGGING		/* only include code if enabled */