905 want llquantize() support in DTrace

Reviewed by: Robert Mustacchi <robert.mustacchi@joyent.com>
Reviewed by: David Pacheco <dap@joyent.com>
Approved by: Garrett D'Amore <garrett@nexenta.com>

1 files changed, 88 insertions, 1 deletions

diff --git a/usr/src/lib/libdtrace/common/dt_aggregate.c b/usr/src/lib/libdtrace/common/dt_aggregate.c
index 2e66250b88..bb766f71c4 100644
--- a/usr/src/lib/libdtrace/common/dt_aggregate.c
+++ b/usr/src/lib/libdtrace/common/dt_aggregate.c
@@ -24,7 +24,9 @@
  * Use is subject to license terms.
  */
 
-#pragma ident	"%Z%%M%	%I%	%E% SMI"
+/*
+ * Copyright (c) 2011, Joyent, Inc. All rights reserved.
+ */
 
 #include <stdlib.h>
 #include <strings.h>
@@ -204,6 +206,83 @@ dt_aggregate_lquantizedcmp(int64_t *lhs, int64_t *rhs)
 	return (0);
 }
 
+static void
+dt_aggregate_llquantize(int64_t *existing, int64_t *new, size_t size)
+{
+	int i;
+
+	for (i = 1; i < size / sizeof (int64_t); i++)
+		existing[i] = existing[i] + new[i];
+}
+
+static long double
+dt_aggregate_llquantizedsum(int64_t *llquanta)
+{
+	int64_t arg = *llquanta++;
+	uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg);
+	uint16_t low = DTRACE_LLQUANTIZE_LOW(arg);
+	uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg);
+	uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg);
+	int bin = 0, order;
+	int64_t value = 1, next, step;
+	long double total;
+
+	assert(nsteps >= factor);
+	assert(nsteps % factor == 0);
+
+	for (order = 0; order < low; order++)
+		value *= factor;
+
+	total = (long double)llquanta[bin++] * (long double)(value - 1);
+
+	next = value * factor;
+	step = next > nsteps ? next / nsteps : 1;
+
+	while (order <= high) {
+		assert(value < next);
+		total += (long double)llquanta[bin++] * (long double)(value);
+
+		if ((value += step) != next)
+			continue;
+
+		next = value * factor;
+		step = next > nsteps ? next / nsteps : 1;
+		order++;
+	}
+
+	return (total + (long double)llquanta[bin] * (long double)value);
+}
+
+static int
+dt_aggregate_llquantizedcmp(int64_t *lhs, int64_t *rhs)
+{
+	long double lsum = dt_aggregate_llquantizedsum(lhs);
+	long double rsum = dt_aggregate_llquantizedsum(rhs);
+	int64_t lzero, rzero;
+
+	if (lsum < rsum)
+		return (DT_LESSTHAN);
+
+	if (lsum > rsum)
+		return (DT_GREATERTHAN);
+
+	/*
+	 * If they're both equal, then we will compare based on the weights at
+	 * zero.  If the weights at zero are equal, then this will be judged a
+	 * tie and will be resolved based on the key comparison.
+	 */
+	lzero = lhs[1];
+	rzero = rhs[1];
+
+	if (lzero < rzero)
+		return (DT_LESSTHAN);
+
+	if (lzero > rzero)
+		return (DT_GREATERTHAN);
+
+	return (0);
+}
+
 static int
 dt_aggregate_quantizedcmp(int64_t *lhs, int64_t *rhs)
 {
@@ -582,6 +661,10 @@ hashnext:
 			h->dtahe_aggregate = dt_aggregate_lquantize;
 			break;
 
+		case DTRACEAGG_LLQUANTIZE:
+			h->dtahe_aggregate = dt_aggregate_llquantize;
+			break;
+
 		case DTRACEAGG_COUNT:
 		case DTRACEAGG_SUM:
 		case DTRACEAGG_AVG:
@@ -849,6 +932,10 @@ dt_aggregate_valcmp(const void *lhs, const void *rhs)
 		rval = dt_aggregate_lquantizedcmp(laddr, raddr);
 		break;
 
+	case DTRACEAGG_LLQUANTIZE:
+		rval = dt_aggregate_llquantizedcmp(laddr, raddr);
+		break;
+
 	case DTRACEAGG_COUNT:
 	case DTRACEAGG_SUM:
 	case DTRACEAGG_MIN: