xref: /OK3568_Linux_fs/kernel/Documentation/scheduler/sched-pelt.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * The following program is used to generate the constants for
3*4882a593Smuzhiyun  * computing sched averages.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * ==============================================================
6*4882a593Smuzhiyun  *		C program (compile with -lm)
7*4882a593Smuzhiyun  * ==============================================================
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <math.h>
11*4882a593Smuzhiyun #include <stdio.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #define HALFLIFE 32
14*4882a593Smuzhiyun #define SHIFT 32
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun double y;
17*4882a593Smuzhiyun 
calc_runnable_avg_yN_inv(void)18*4882a593Smuzhiyun void calc_runnable_avg_yN_inv(void)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun 	int i;
21*4882a593Smuzhiyun 	unsigned int x;
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun 	/* To silence -Wunused-but-set-variable warnings. */
24*4882a593Smuzhiyun 	printf("static const u32 runnable_avg_yN_inv[] __maybe_unused = {");
25*4882a593Smuzhiyun 	for (i = 0; i < HALFLIFE; i++) {
26*4882a593Smuzhiyun 		x = ((1UL<<32)-1)*pow(y, i);
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 		if (i % 6 == 0) printf("\n\t");
29*4882a593Smuzhiyun 		printf("0x%8x, ", x);
30*4882a593Smuzhiyun 	}
31*4882a593Smuzhiyun 	printf("\n};\n\n");
32*4882a593Smuzhiyun }
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun int sum = 1024;
35*4882a593Smuzhiyun 
calc_runnable_avg_yN_sum(void)36*4882a593Smuzhiyun void calc_runnable_avg_yN_sum(void)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun 	int i;
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun 	printf("static const u32 runnable_avg_yN_sum[] = {\n\t    0,");
41*4882a593Smuzhiyun 	for (i = 1; i <= HALFLIFE; i++) {
42*4882a593Smuzhiyun 		if (i == 1)
43*4882a593Smuzhiyun 			sum *= y;
44*4882a593Smuzhiyun 		else
45*4882a593Smuzhiyun 			sum = sum*y + 1024*y;
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 		if (i % 11 == 0)
48*4882a593Smuzhiyun 			printf("\n\t");
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 		printf("%5d,", sum);
51*4882a593Smuzhiyun 	}
52*4882a593Smuzhiyun 	printf("\n};\n\n");
53*4882a593Smuzhiyun }
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun int n = -1;
56*4882a593Smuzhiyun /* first period */
57*4882a593Smuzhiyun long max = 1024;
58*4882a593Smuzhiyun 
calc_converged_max(void)59*4882a593Smuzhiyun void calc_converged_max(void)
60*4882a593Smuzhiyun {
61*4882a593Smuzhiyun 	long last = 0, y_inv = ((1UL<<32)-1)*y;
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun 	for (; ; n++) {
64*4882a593Smuzhiyun 		if (n > -1)
65*4882a593Smuzhiyun 			max = ((max*y_inv)>>SHIFT) + 1024;
66*4882a593Smuzhiyun 			/*
67*4882a593Smuzhiyun 			 * This is the same as:
68*4882a593Smuzhiyun 			 * max = max*y + 1024;
69*4882a593Smuzhiyun 			 */
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun 		if (last == max)
72*4882a593Smuzhiyun 			break;
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun 		last = max;
75*4882a593Smuzhiyun 	}
76*4882a593Smuzhiyun 	n--;
77*4882a593Smuzhiyun 	printf("#define LOAD_AVG_PERIOD %d\n", HALFLIFE);
78*4882a593Smuzhiyun 	printf("#define LOAD_AVG_MAX %ld\n", max);
79*4882a593Smuzhiyun //	printf("#define LOAD_AVG_MAX_N %d\n\n", n);
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun 
calc_accumulated_sum_32(void)82*4882a593Smuzhiyun void calc_accumulated_sum_32(void)
83*4882a593Smuzhiyun {
84*4882a593Smuzhiyun 	int i, x = sum;
85*4882a593Smuzhiyun 
86*4882a593Smuzhiyun 	printf("static const u32 __accumulated_sum_N32[] = {\n\t     0,");
87*4882a593Smuzhiyun 	for (i = 1; i <= n/HALFLIFE+1; i++) {
88*4882a593Smuzhiyun 		if (i > 1)
89*4882a593Smuzhiyun 			x = x/2 + sum;
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun 		if (i % 6 == 0)
92*4882a593Smuzhiyun 			printf("\n\t");
93*4882a593Smuzhiyun 
94*4882a593Smuzhiyun 		printf("%6d,", x);
95*4882a593Smuzhiyun 	}
96*4882a593Smuzhiyun 	printf("\n};\n\n");
97*4882a593Smuzhiyun }
98*4882a593Smuzhiyun 
main(void)99*4882a593Smuzhiyun void main(void)
100*4882a593Smuzhiyun {
101*4882a593Smuzhiyun 	printf("/* Generated by Documentation/scheduler/sched-pelt; do not modify. */\n\n");
102*4882a593Smuzhiyun 
103*4882a593Smuzhiyun 	y = pow(0.5, 1/(double)HALFLIFE);
104*4882a593Smuzhiyun 
105*4882a593Smuzhiyun 	calc_runnable_avg_yN_inv();
106*4882a593Smuzhiyun //	calc_runnable_avg_yN_sum();
107*4882a593Smuzhiyun 	calc_converged_max();
108*4882a593Smuzhiyun //	calc_accumulated_sum_32();
109*4882a593Smuzhiyun }
110