Add -m and -M options to control the minimum and maximum frequency.

PR:	bin/145063
Submitted by:	Boris Kochergin <spawk at acm.poly.edu>
Reviewed by:	cperciva
Approved by:	rrs (mentor)
MFC after: 2 weeks

usr.sbin/powerd/powerd.8

@@ -35,6 +35,8 @@
 .Op Fl a Ar mode
 .Op Fl b Ar mode
 .Op Fl i Ar percent
+.Op Fl m Ar freq
+.Op Fl M Ar freq
 .Op Fl n Ar mode
 .Op Fl p Ar ival
 .Op Fl P Ar pidfile
@@ -79,6 +81,10 @@ to use while on battery power.
 Specifies the CPU load percent level when adaptive
 mode should begin to degrade performance to save power.
 The default is 50% or lower.
+.It Fl m Ar freq
+Specifies the minimum frequency to throttle down to.
+.It Fl M Ar freq
+Specifies the maximum frequency to throttle up to.
 .It Fl n Ar mode
 Selects the
 .Ar mode

usr.sbin/powerd/powerd.c

@@ -84,7 +84,8 @@ const char *modes[] = {
 #define DEVCTL_MAXBUF	1024
 
 static int	read_usage_times(int *load);
-static int	read_freqs(int *numfreqs, int **freqs, int **power);
+static int	read_freqs(int *numfreqs, int **freqs, int **power,
+		    int minfreq, int maxfreq);
 static int	set_freq(int freq);
 static void	acline_init(void);
 static void	acline_read(void);
@@ -174,10 +175,10 @@ read_usage_times(int *load)
 }
 
 static int
-read_freqs(int *numfreqs, int **freqs, int **power)
+read_freqs(int *numfreqs, int **freqs, int **power, int minfreq, int maxfreq)
 {
 	char *freqstr, *p, *q;
-	int i;
+	int i, j;
 	size_t len = 0;
 
 	if (sysctl(levels_mib, 4, NULL, &len, NULL, 0))
@@ -201,19 +202,30 @@ read_freqs(int *numfreqs, int **freqs, int **power)
 		free(*freqs);
 		return (-1);
 	}
-	for (i = 0, p = freqstr; i < *numfreqs; i++) {
+	for (i = 0, j = 0, p = freqstr; i < *numfreqs; i++) {
 		q = strchr(p, ' ');
 		if (q != NULL)
 			*q = '\0';
-		if (sscanf(p, "%d/%d", &(*freqs)[i], &(*power)[i]) != 2) {
+		if (sscanf(p, "%d/%d", &(*freqs)[j], &(*power)[i]) != 2) {
 			free(freqstr);
 			free(*freqs);
 			free(*power);
 			return (-1);
 		}
+		if (((*freqs)[j] >= minfreq || minfreq == -1) &&
+		    ((*freqs)[j] <= maxfreq || maxfreq == -1))
+			j++;
 		p = q + 1;
 	}
 
+	*numfreqs = j;
+	if ((*freqs = realloc(*freqs, *numfreqs * sizeof(int))) == NULL) {
+		free(freqstr);
+		free(*freqs);
+		free(*power);
+		return (-1);
+	}
+
 	free(freqstr);
 	return (0);
 }
@@ -422,7 +434,7 @@ usage(void)
 {
 
 	fprintf(stderr,
-"usage: powerd [-v] [-a mode] [-b mode] [-i %%] [-n mode] [-p ival] [-r %%] [-P pidfile]\n");
+"usage: powerd [-v] [-a mode] [-b mode] [-i %%] [-m freq] [-M freq] [-n mode] [-p ival] [-r %%] [-P pidfile]\n");
 	exit(1);
 }
 
@@ -435,6 +447,7 @@ main(int argc, char * argv[])
 	struct pidfh *pfh = NULL;
 	const char *pidfile = NULL;
 	int freq, curfreq, initfreq, *freqs, i, j, *mwatts, numfreqs, load;
+	int minfreq = -1, maxfreq = -1;
 	int ch, mode, mode_ac, mode_battery, mode_none, idle, to;
 	uint64_t mjoules_used;
 	size_t len;
@@ -452,7 +465,7 @@ main(int argc, char * argv[])
 	if (geteuid() != 0)
 		errx(1, "must be root to run");
 
-	while ((ch = getopt(argc, argv, "a:b:i:n:p:P:r:v")) != -1)
+	while ((ch = getopt(argc, argv, "a:b:i:m:M:n:p:P:r:v")) != -1)
 		switch (ch) {
 		case 'a':
 			parse_mode(optarg, &mode_ac, ch);
@@ -468,6 +481,22 @@ main(int argc, char * argv[])
 				usage();
 			}
 			break;
+		case 'm':
+			minfreq = atoi(optarg);
+			if (minfreq < 0) {
+				warnx("%d is not a valid CPU frequency",
+				    minfreq);
+				usage();
+			}
+			break;
+		case 'M':
+			maxfreq = atoi(optarg);
+			if (maxfreq < 0) {
+				warnx("%d is not a valid CPU frequency",
+				    maxfreq);
+				usage();
+			}
+			break;
 		case 'n':
 			parse_mode(optarg, &mode_none, ch);
 			break;
@@ -515,8 +544,10 @@ main(int argc, char * argv[])
 	/* Check if we can read the load and supported freqs. */
 	if (read_usage_times(NULL))
 		err(1, "read_usage_times");
-	if (read_freqs(&numfreqs, &freqs, &mwatts))
+	if (read_freqs(&numfreqs, &freqs, &mwatts, minfreq, maxfreq))
 		err(1, "error reading supported CPU frequencies");
+	if (numfreqs == 0)
+		errx(1, "no CPU frequencies in user-specified range");
 
 	/* Run in the background unless in verbose mode. */
 	if (!vflag) {
@@ -552,6 +583,49 @@ main(int argc, char * argv[])
 	i = get_freq_id(curfreq, freqs, numfreqs);
 	if (freq < 1)
 		freq = 1;
+
+	/*
+	 * If we are in adaptive mode and the current frequency is outside the
+	 * user-defined range, adjust it to be within the user-defined range.
+	 */
+	acline_read();
+	if (acline_status > SRC_UNKNOWN)
+		errx(1, "invalid AC line status %d", acline_status);
+	if ((acline_status == SRC_AC &&
+	    (mode_ac == MODE_ADAPTIVE || mode_ac == MODE_HIADAPTIVE)) ||
+	    (acline_status == SRC_BATTERY &&
+	    (mode_battery == MODE_ADAPTIVE || mode_battery == MODE_HIADAPTIVE)) ||
+	    (acline_status == SRC_UNKNOWN &&
+	    (mode_none == MODE_ADAPTIVE || mode_none == MODE_HIADAPTIVE))) {
+		/* Read the current frequency. */
+		len = sizeof(curfreq);
+		if (sysctl(freq_mib, 4, &curfreq, &len, NULL, 0) != 0) {
+			if (vflag)
+				warn("error reading current CPU frequency");
+		}
+		if (curfreq < freqs[numfreqs - 1]) {
+			if (vflag) {
+				printf("CPU frequency is below user-defined "
+				    "minimum; changing frequency to %d "
+				    "MHz\n", freqs[numfreqs - 1]);
+			}
+			if (set_freq(freqs[numfreqs - 1]) != 0) {
+				warn("error setting CPU freq %d",
+				    freqs[numfreqs - 1]);
+			}
+		} else if (curfreq > freqs[0]) {
+			if (vflag) {
+				printf("CPU frequency is above user-defined "
+				    "maximum; changing frequency to %d "
+				    "MHz\n", freqs[0]);
+			}
+			if (set_freq(freqs[0]) != 0) {
+				warn("error setting CPU freq %d",
+				    freqs[0]);
+			}
+		}
+	}
+
 	idle = 0;
 	/* Main loop. */
 	for (;;) {