lineage_kernel_xcoverpro/Documentation/scheduler/sched-pelt.c

127 lines
2.4 KiB
C
Executable File

/*
* The following program is used to generate the constants for
* computing sched averages.
*
* ==============================================================
* C program (compile with -lm)
* ==============================================================
*/
#include <math.h>
#include <stdio.h>
#define HALFLIFE { 32, 16, 8 }
#define SHIFT 32
double y;
void calc_runnable_avg_yN_inv(const int halflife)
{
int i;
unsigned int x;
printf("static const u32 runnable_avg_yN_inv[] = {");
for (i = 0; i < halflife; i++) {
x = ((1UL<<32)-1)*pow(y, i);
if (i % 4 == 0) printf("\n\t");
printf("0x%8x,", x);
}
printf("\n};\n\n");
}
int sum;
void calc_runnable_avg_yN_sum(const int halflife)
{
int i;
printf("static const u32 runnable_avg_yN_sum[] = {\n\t 0,");
for (i = 1; i <= halflife; i++) {
if (i == 1)
sum *= y;
else
sum = sum*y + 1024*y;
if (i % 11 == 0)
printf("\n\t");
printf("%5d,", sum);
}
printf("\n};\n\n");
}
int n;
long max;
void calc_converged_max(const int halflife)
{
long last = 0, y_inv = ((1UL<<32)-1)*y;
for (; ; n++) {
if (n > -1)
max = ((max*y_inv)>>SHIFT) + 1024;
/*
* This is the same as:
* max = max*y + 1024;
*/
if (last == max)
break;
last = max;
}
n--;
printf("#define LOAD_AVG_PERIOD %d\n", halflife);
printf("#define LOAD_AVG_MAX %ld\n", max);
printf("#define LOAD_AVG_MAX_N %d\n\n", n);
}
void calc_accumulated_sum_32(const int halflife)
{
int i, x = sum;
printf("static const u32 __accumulated_sum_N32[] = {\n\t 0,");
for (i = 1; i <= n/halflife+1; i++) {
if (i > 1)
x = x/2 + sum;
if (i % 6 == 0)
printf("\n\t");
printf("%6d,", x);
}
printf("\n};\n\n");
}
void main(void)
{
int hl_value[] = HALFLIFE;
int hl_count = sizeof(hl_value) / sizeof(int);
int hl_idx, halflife;
printf("/* SPDX-License-Identifier: GPL-2.0 */\n");
printf("/* Generated by Documentation/scheduler/sched-pelt; do not modify. */\n");
for (hl_idx = 0; hl_idx < hl_count; ++hl_idx) {
halflife = hl_value[hl_idx];
y = pow(0.5, 1/(double)halflife);
sum = 1024;
/* first period */
max = 1024;
n = -1;
printf("\n#ifdef CONFIG_PELT_UTIL_HALFLIFE_%d\n", halflife);
calc_runnable_avg_yN_inv(halflife);
calc_runnable_avg_yN_sum(halflife);
calc_converged_max(halflife);
/*
* calc_accumulated_sum_32(halflife) precomputed load sum table of half-life,
* not used yet.
*/
printf("#endif\n");
}
}