From ab19351c394ed830184e61e8c97f6253f3f3eb21 Mon Sep 17 00:00:00 2001
From: Nate Lawson <njl@FreeBSD.org>
Date: Sun, 10 Apr 2005 19:02:29 +0000
Subject: [PATCH] Add support for recording the total energy used (in joules)
 when in verbose mode.  This is useful for profiling new adaptive algorithms
 in performance (via time(1)) and total energy consumed for a given workload.

---
 usr.sbin/powerd/powerd.c | 53 +++++++++++++++++++++++++++++++++++-----
 1 file changed, 47 insertions(+), 6 deletions(-)

diff --git a/usr.sbin/powerd/powerd.c b/usr.sbin/powerd/powerd.c
index 18566d2ffec4..a2ecb48cfb20 100644
--- a/usr.sbin/powerd/powerd.c
+++ b/usr.sbin/powerd/powerd.c
@@ -30,6 +30,7 @@ __FBSDID("$FreeBSD$");
 
 #include <err.h>
 #include <fcntl.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -69,10 +70,11 @@ const char *modes[] = {
 #define APMDEV		"/dev/apm"
 
 static int	read_usage_times(long *idle, long *total);
-static int	read_freqs(int *numfreqs, int **freqs);
+static int	read_freqs(int *numfreqs, int **freqs, int **power);
 static int	set_freq(int freq);
 static void	acline_init(void);
 static int	acline_read(void);
+static void	handle_sigs(int sig);
 static void	parse_mode(char *arg, int *mode, int ch);
 static void	usage(void);
 
@@ -88,6 +90,7 @@ static int	cpu_idle_mark;
 static int	poll_ival;
 
 static int	apm_fd;
+static int	exit_requested;
 
 static int
 read_usage_times(long *idle, long *total)
@@ -116,7 +119,7 @@ read_usage_times(long *idle, long *total)
 }
 
 static int
-read_freqs(int *numfreqs, int **freqs)
+read_freqs(int *numfreqs, int **freqs, int **power)
 {
 	char *freqstr, *p, *q;
 	int i;
@@ -138,13 +141,19 @@ read_freqs(int *numfreqs, int **freqs)
 		free(freqstr);
 		return (-1);
 	}
+	if ((*power = malloc(*numfreqs * sizeof(int))) == NULL) {
+		free(freqstr);
+		free(*freqs);
+		return (-1);
+	}
 	for (i = 0, p = freqstr; i < *numfreqs; i++) {
 		q = strchr(p, ' ');
 		if (q != NULL)
 			*q = '\0';
-		if (sscanf(p, "%d/%*d", &(*freqs)[i]) != 1) {
+		if (sscanf(p, "%d/%d", &(*freqs)[i], &(*power)[i]) != 2) {
 			free(freqstr);
 			free(*freqs);
+			free(*power);
 			return (-1);
 		}
 		p = q + 1;
@@ -224,6 +233,12 @@ parse_mode(char *arg, int *mode, int ch)
 		errx(1, "bad option: -%c %s", (char)ch, optarg);
 }
 
+static void
+handle_sigs(int __unused sig)
+{
+	exit_requested = 1;
+}
+
 static void
 usage(void)
 {
@@ -237,8 +252,9 @@ int
 main(int argc, char * argv[])
 {
 	long idle, total;
-	int curfreq, *freqs, i, numfreqs;
+	int curfreq, *freqs, i, *mwatts, numfreqs;
 	int ch, mode_ac, mode_battery, mode_none, acline, mode, vflag;
+	uint64_t mjoules_used;
 	size_t len;
 
 	/* Default mode for all AC states is adaptive. */
@@ -246,6 +262,7 @@ main(int argc, char * argv[])
 	cpu_running_mark = DEFAULT_ACTIVE_PERCENT;
 	cpu_idle_mark = DEFAULT_IDLE_PERCENT;
 	poll_ival = DEFAULT_POLL_INTERVAL;
+	mjoules_used = 0;
 	vflag = 0;
 	apm_fd = -1;
 
@@ -307,7 +324,7 @@ main(int argc, char * argv[])
 	/* Check if we can read the idle time and supported freqs. */
 	if (read_usage_times(NULL, NULL))
 		err(1, "read_usage_times");
-	if (read_freqs(&numfreqs, &freqs))
+	if (read_freqs(&numfreqs, &freqs, &mwatts))
 		err(1, "error reading supported CPU frequencies");
 
 	/* Decide whether to use ACPI or APM to read the AC line status. */
@@ -316,12 +333,23 @@ main(int argc, char * argv[])
 	/* Run in the background unless in verbose mode. */
 	if (!vflag)
 		daemon(0, 0);
+	signal(SIGINT, handle_sigs);
+	signal(SIGTERM, handle_sigs);
 
 	/* Main loop. */
 	for (;;) {
 		/* Check status every few milliseconds. */
 		usleep(poll_ival);
 
+		/* If the user requested we quit, print some statistics. */
+		if (exit_requested) {
+			if (vflag && mjoules_used != 0)
+				printf("total joules used: %u.%03u\n",
+				    (u_int)(mjoules_used / 1000),
+				    (int)mjoules_used % 1000);
+			break;
+		}
+
 		/* Read the current AC status and record the mode. */
 		acline = acline_read();
 		switch (acline) {
@@ -343,6 +371,18 @@ main(int argc, char * argv[])
 		if (sysctl(freq_mib, 4, &curfreq, &len, NULL, 0))
 			err(1, "error reading current CPU frequency");
 
+		if (vflag) {
+			for (i = 0; i < numfreqs; i++) {
+				if (freqs[i] == curfreq)
+					break;
+			}
+
+			/* Keep a sum of all power actually used. */
+			if (i < numfreqs && mwatts[i] != -1)
+				mjoules_used +=
+				    (mwatts[i] * (poll_ival / 1000)) / 1000;
+		}
+
 		/* Always switch to the lowest frequency in min mode. */
 		if (mode == MODE_MIN) {
 			if (curfreq != freqs[numfreqs - 1]) {
@@ -409,7 +449,8 @@ main(int argc, char * argv[])
 				    freqs[i]);
 		}
 	}
-	/* NOTREACHED */
+	free(freqs);
+	free(mwatts);
 
 	exit(0);
 }