source: benchmark/readyQ/cycle.cfa@ b35ab2d

#include "rq_bench.hfa"

thread Partner {
        Partner * partner;
        unsigned long long count;
        bool first;
};

void ?{}( Partner & this ) {
        ((thread&)this){ bench_cluster };
}

void main( Partner & this ) {
        thread_loop {
                park();
                unpark( *this.partner );
        }

        __atomic_fetch_add(&threads_left, -1, __ATOMIC_SEQ_CST);

        if(this.first) park();
}

int main(int argc, char * argv[]) {
        unsigned ring_size = 2;
        cfa_option opt[] = {
                BENCH_OPT,
                { 'r', "ringsize", "Number of threads in a cycle", ring_size }
        };
        BENCH_OPT_PARSE("cforall cycle benchmark");

        {
                unsigned long long global_counter = 0;
                unsigned tthreads = nthreads * ring_size;
                Time start, end;
                BenchCluster bc = { nprocs };
                {
                        threads_left = tthreads;
                        Partner threads[tthreads];
                        for(i; tthreads) {
                                unsigned pi = (i + nthreads) % tthreads;
                                threads[i].partner = &threads[pi];
                                threads[i].first = i < nthreads;
                        }
                        printf("Starting\n");

                        bool is_tty = isatty(STDOUT_FILENO);
                        start = getTimeNsec();

                        for(i; nthreads) {
                                unpark( threads[i] );
                        }
                        wait(start, end, is_tty);

                        stop = true;
                        end = getTimeNsec();
                        printf("\nDone\n");

                        for(i; tthreads) {
                                global_counter += join( threads[i] ).count;
                        }
                }

                printf("Took %'ld ms\n", (end - start)`ms);
                printf("Yields per second   : %'18.2lf\n", ((double)global_counter) / (end - start)`s);
                printf("ns per yields       : %'18.2lf\n", ((double)(end - start)`ns) / global_counter);
                printf("Total yields        : %'15llu\n", global_counter);
                printf("Yields per threads  : %'15llu\n", global_counter / tthreads);
                printf("Yields per procs    : %'15llu\n", global_counter / nprocs);
                printf("Yields/sec/procs    : %'18.2lf\n", (((double)global_counter) / nprocs) / (end - start)`s);
                printf("ns per yields/procs : %'18.2lf\n", ((double)(end - start)`ns) / (global_counter / nprocs));
                fflush(stdout);
        }

        return 0;
}