misc/104689: add support for limiting cpu frequency on adaptive mode

[redchrom at gmail.com]

>Number:         104689
>Category:       misc
>Synopsis:       add support for limiting cpu frequency on adaptive mode
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Sun Oct 22 22:10:14 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Stepan Zastupov (RedChrom)
>Release:        FreeBSD 7.0-CURRENT i386
>Organization:
ISPSystem
>Environment:
System: FreeBSD stepan.ispsystem.net 7.0-CURRENT FreeBSD 7.0-CURRENT #5: Fri Oct 20 11:51:51 IRKST 2006 root at stepan.ispsystem.net:/usr/obj/usr/src/sys/LILITH i386


	
>Description:
	Adaptive mode really helps to prolong life of battery but with low idle it sets maximum frequency. I think limit maximum frequency on adaptive mode it's good idea. I know patch is very dirty but I hope you'll like my idea.
>How-To-Repeat:
	
	Apply the patch and run powerd:
	powerd -a maximum -b adaptive -m 558
	Where 558 is maximum frequency on adaptive mode
>Fix:

	

--- powerd.c.diff begins here ---
--- powerd.c.orig	Mon Oct 23 06:08:17 2006
+++ powerd.c	Mon Oct 23 06:54:31 2006
@@ -370,7 +370,7 @@
 	struct pidfh *pfh = NULL;
 	const char *pidfile = NULL;
 	long idle, total;
-	int curfreq, *freqs, i, *mwatts, numfreqs;
+	int curfreq, *freqs, i, *mwatts, numfreqs, maxfreq;
 	int ch, mode, mode_ac, mode_battery, mode_none;
 	uint64_t mjoules_used;
 	size_t len;
@@ -382,12 +382,13 @@
 	poll_ival = DEFAULT_POLL_INTERVAL;
 	mjoules_used = 0;
 	vflag = 0;
+	maxfreq = 0;
 
 	/* User must be root to control frequencies. */
 	if (geteuid() != 0)
 		errx(1, "must be root to run");
 
-	while ((ch = getopt(argc, argv, "a:b:i:n:p:P:r:v")) != EOF)
+	while ((ch = getopt(argc, argv, "a:b:i:n:p:P:r:m:v")) != EOF)
 		switch (ch) {
 		case 'a':
 			parse_mode(optarg, &mode_ac, ch);
@@ -424,6 +425,9 @@
 				usage();
 			}
 			break;
+		case 'm':
+			maxfreq = atoi(optarg);
+			break;
 		case 'v':
 			vflag = 1;
 			break;
@@ -592,9 +596,19 @@
 			if (freqs[i] == curfreq)
 				break;
 		}
+
+		if (maxfreq == 0)
+			maxfreq = freqs[0];
+
 		if (idle < (total * cpu_running_mark) / 100 &&
-		    curfreq < freqs[0]) {
-			i -= 2;
+			curfreq < maxfreq) {
+			/*
+			 * I know, next three lines is dirty
+			 */
+			i -= 1;
+			if (freqs[i] < maxfreq)
+				i -= 1;
+
 			if (i < 0)
 				i = 0;
 			if (vflag) {
--- powerd.c.diff ends here ---


>Release-Note:
>Audit-Trail:
>Unformatted: