litmus-rt.git - The LITMUS^RT kernel.

diff options

Diffstat (limited to 'lib/genalloc.c')

0 files changed, 0 insertions, 0 deletions

#include <sys/time.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <time.h> #include <string.h> #include "litmus.h" #include "common.h" static double cputime() { struct timespec ts; int err; err = clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts); if (err != 0) perror("clock_gettime"); return (ts.tv_sec + 1E-9 * ts.tv_nsec); } static double wctime() { struct timeval tv; gettimeofday(&tv, NULL); return (tv.tv_sec + 1E-6 * tv.tv_usec); } void usage(char *error) { fprintf(stderr, "Error: %s\n", error); fprintf(stderr, "Usage: rt_spin [-w] task_parameters_file duration\n" " rt_spin -l\n"); exit(1); } #define NUMS 4096 static int num[NUMS]; static double loop_length = 1.0; static char* progname; static int loop_once(void) { int i, j = 0; for (i = 0; i < NUMS; i++) j += num[i]++; return j; } static int loop_for(double exec_time) { double t = 0; int tmp = 0; /* while (t + loop_length < exec_time) { tmp += loop_once(); t += loop_length; } */ double start = cputime(); double now = cputime(); while (now + loop_length < start + exec_time) { tmp += loop_once(); t += loop_length; now = cputime(); } return tmp; } static void fine_tune(double interval) { double start, end, delta; start = wctime(); loop_for(interval); end = wctime(); delta = (end - start - interval) / interval; if (delta != 0) loop_length = loop_length / (1 - delta); } static void configure_loop(void) { double start; /* prime cache */ loop_once(); loop_once(); loop_once(); /* measure */ start = wctime(); loop_once(); /* hope we didn't get preempted */ loop_length = wctime(); loop_length -= start; /* fine tune */ fine_tune(0.1); fine_tune(0.1); fine_tune(0.1); } static void show_loop_length(void) { printf("%s/%d: loop_length=%f (%ldus)\n", progname, getpid(), loop_length, (long) (loop_length * 1000000)); } static void debug_delay_loop(void) { double start, end, delay; show_loop_length(); while (1) { for (delay = 0.5; delay > 0.01; delay -= 0.01) { start = wctime(); loop_for(delay); end = wctime(); printf("%6.4fs: looped for %10.8fs, delta=%11.8fs, error=%7.4f%%\n", delay, end - start, end - start - delay, 100 * (end - start - delay) / delay); } } } static int job(double exec_time) { loop_for(exec_time); sleep_next_period(); return 0; } #define fms_to_ns(x) (lt_t)(((x) * __NS_PER_MS)) /* * <task_id, cpu, deadline (from job release), budget, offset> . */ int parse_edfwm_slice(FILE *ts, int slices_no, int task_id, struct edf_wm_params *wm) { int i, tid; unsigned int cpu; double deadline, budget, offset; for (i = 0; i < slices_no; i++) { if (fscanf(ts, "%d %u %lf %lf %lf\n", &tid, &cpu, &deadline, &budget, &offset) != EOF) { printf("slice(tid, cpu, d, e, ph) = (%d, %u, %lf, %lf, %lf)\n", tid, cpu, deadline, budget, offset); if (task_id != tid) { fprintf(stderr, "task_id %d != tid %d\n", task_id, tid); return -1; } wm->slices[i].deadline = fms_to_ns(deadline); wm->slices[i].budget = fms_to_ns(budget); wm->slices[i].offset = fms_to_ns(offset); } if (ferror(ts)) { fprintf(stderr, "Cannot read file\n"); return -1; } } return 1; } /* Custom format to read parameters for tasks from a plain text file: * <task_id, execution_cost, period, phase, cpu, slices_number> . * If the task is split on multiple slices, slices_number is non 0 * and we scan a list of slice parameters up to slices_number: * <task_id, cpu, deadline (from job release), budget, offset> . * The offset is the start time for the slice relative to the job release. * * FIXME: this function should go in a separate file where all the parsing * funtions for the semi-part plugins are. It will help in later testing with * "tasks" programs. */ int parse_edfwm_ts_file(FILE *ts, struct rt_task *rt) { int task_id, ret = 1; unsigned int cpu, sliceno; double fwcet, fperiod, fphase; ret = fscanf(ts, "%d %lf %lf %lf %d %d\n", &task_id, &fwcet, &fperiod, &fphase, &cpu, &sliceno); if (ret != EOF) { printf("(tid, wcet, period, ph, cpu, slices) = " "(%d, %.2f, %.2f, %.2f, %u, %u)\n", task_id, fwcet, fperiod, fphase, cpu, sliceno); rt->exec_cost = fms_to_ns(fwcet); rt->period = fms_to_ns(fperiod); rt->phase = fms_to_ns(fphase); rt->cpu = cpu; rt->cls = RT_CLASS_HARD; rt->budget_policy = PRECISE_ENFORCEMENT; if (sliceno > 0) { ret = parse_edfwm_slice(ts, sliceno, task_id, (struct edf_wm_params*) &rt->semi_part); if (ret < 0) goto err; } } if (ferror(ts)) goto err; return EOF; err: fprintf(stderr, "Error parsing file\n"); return -1; }


context:
space:
mode: