/**
* @brief Timer handler procedure
*
* This is not a realistic workload and it is a demonstration code only.
*
* It runs couple thousand of iterations and each iteration is randomizing
* memory locations to run a number of arithmetic operations on them.
*
* @param sig UNUSED
* @param si UNUSED
* @param uc UNUSED
*/
static void timer_handler(int sig, siginfo_t *si, void *uc)
{
const int num_iterations = 5000;
int *p = (int *) timer_data_ptr;
const size_t sz = timer_data_size / sizeof(int);
int m;
(void) (sig);
(void) (si);
(void) (uc);
tsc_start(&timer_prof);
/* START - "latency sensitive" code */
for (m = 0; m < num_iterations; m++) {
const size_t stride = 5;
const int idx0 = timer_rand() % (sz - stride);
const int idx1 = timer_rand() % (sz - stride);
size_t n;
for (n = 0; n < stride; n++)
p[idx0 + n] = 2 * p[idx1 + n] + p[idx0 + n];
}
/* END - "latency sensitive" code */
tsc_end(&timer_prof, 1);
}
int main(void) {
const long iterations = 1000000000;
struct timespec ts;
uint64_t tsc;
clock_start (&ts);
tsc_start(&tsc);
volatile int asignto = 0;
for (long i = 0; i < iterations; i++) {
asignto = function_call(i);
}
const long long unsigned delta = clock_end(&ts);
const long long unsigned delta_tsc = tsc_end(&tsc);
(void) asignto;
printf("%ld spins in %lluns (%.1fns/spin, %.1f clocks/spin)\n",
iterations, delta, (delta / (double) iterations),delta_tsc / (double)iterations);
return 0;
}
