/* -*- mode: C; c-basic-offset: 4 -*- */
#include <stdio.h>
#include <errno.h>

#include "toku_portability.h"
#include "toku_assert.h"
#include "toku_os.h"
#include "toku_pthread.h"
#include "workqueue.h"
#include "threadpool.h"
#include "toku_worker.h"

// Create fixed number of worker threads, all waiting on a single queue
// of work items (WORKQUEUE).

void toku_init_workers(WORKQUEUE wq, THREADPOOL *tpptr) {
    workqueue_init(wq);
    int nprocs = toku_os_get_number_active_processors();
    threadpool_create(tpptr, nprocs);
    int i;
    for (i=0; i<nprocs; i++)
        threadpool_maybe_add(*tpptr, toku_worker, wq);
}

void toku_destroy_workers(WORKQUEUE wq, THREADPOOL *tpptr) {
    workqueue_set_closed(wq, 1);       // close the work queue and [see "A" in toku_worker()]
    threadpool_destroy(tpptr);         // wait for all of the worker threads to exit
    workqueue_destroy(wq);    
}

void *toku_worker(void *arg) {
    // printf("%lu:%s:start %p\n", toku_pthread_self(), __FUNCTION__, arg);
    WORKQUEUE wq = arg;
    int r;
    while (1) {
        WORKITEM wi = 0;
        r = workqueue_deq(wq, &wi, 1); // get work from the queue, block if empty
        if (r != 0)                    // shut down worker threads when work queue is closed 
            break;                     // [see "A" in toku_destroy_workers() ]
        wi->f(wi);                     // call the work handler function
    }
    // printf("%lu:%s:exit %p\n", toku_pthread_self(), __FUNCTION__, arg);
    return arg;
}