examples/performance-thread/pthread_shim/pthread_shim.c

/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2015 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <errno.h>
#define __USE_GNU
#include <sched.h>
#include <dlfcn.h>

#include <rte_log.h>

#include "lthread_api.h"
#include "pthread_shim.h"

#define RTE_LOGTYPE_PTHREAD_SHIM RTE_LOGTYPE_USER3

#define POSIX_ERRNO(x)  (x)

/* some releases of FreeBSD 10, e.g. 10.0, don't have CPU_COUNT macro */
#ifndef CPU_COUNT
#define CPU_COUNT(x) __cpu_count(x)

static inline unsigned int
__cpu_count(const rte_cpuset_t *cpuset)
{
    unsigned int i, count = 0;
    for (i = 0; i < RTE_MAX_LCORE; i++)
        if (CPU_ISSET(i, cpuset))
            count++;
    return count;
}
#endif

/*
 * this flag determines at run time if we override pthread
 * calls and map then to equivalent lthread calls
 * or of we call the standard pthread function
 */
static __thread int override;


/*
 * this structures contains function pointers that will be
 * initialised to the loaded address of the real
 * pthread library API functions
 */
struct pthread_lib_funcs {
int (*f_pthread_barrier_destroy)
    (pthread_barrier_t *);
int (*f_pthread_barrier_init)
    (pthread_barrier_t *, const pthread_barrierattr_t *, unsigned);
int (*f_pthread_barrier_wait)
    (pthread_barrier_t *);
int (*f_pthread_cond_broadcast)
    (pthread_cond_t *);
int (*f_pthread_cond_destroy)
    (pthread_cond_t *);
int (*f_pthread_cond_init)
    (pthread_cond_t *, const pthread_condattr_t *);
int (*f_pthread_cond_signal)
    (pthread_cond_t *);
int (*f_pthread_cond_timedwait)
    (pthread_cond_t *, pthread_mutex_t *, const struct timespec *);
int (*f_pthread_cond_wait)
    (pthread_cond_t *, pthread_mutex_t *);
int (*f_pthread_create)
    (pthread_t *, const pthread_attr_t *, void *(*)(void *), void *);
int (*f_pthread_detach)
    (pthread_t);
int (*f_pthread_equal)
    (pthread_t, pthread_t);
void (*f_pthread_exit)
    (void *);
void * (*f_pthread_getspecific)
    (pthread_key_t);
int (*f_pthread_getcpuclockid)
    (pthread_t, clockid_t *);
int (*f_pthread_join)
    (pthread_t, void **);
int (*f_pthread_key_create)
    (pthread_key_t *, void (*) (void *));
int (*f_pthread_key_delete)
    (pthread_key_t);
int (*f_pthread_mutex_destroy)
    (pthread_mutex_t *__mutex);
int (*f_pthread_mutex_init)
    (pthread_mutex_t *__mutex, const pthread_mutexattr_t *);
int (*f_pthread_mutex_lock)
    (pthread_mutex_t *__mutex);
int (*f_pthread_mutex_trylock)
    (pthread_mutex_t *__mutex);
int (*f_pthread_mutex_timedlock)
    (pthread_mutex_t *__mutex, const struct timespec *);
int (*f_pthread_mutex_unlock)
    (pthread_mutex_t *__mutex);
int (*f_pthread_once)
    (pthread_once_t *, void (*) (void));
int (*f_pthread_rwlock_destroy)
    (pthread_rwlock_t *__rwlock);
int (*f_pthread_rwlock_init)
    (pthread_rwlock_t *__rwlock, const pthread_rwlockattr_t *);
int (*f_pthread_rwlock_rdlock)
    (pthread_rwlock_t *__rwlock);
int (*f_pthread_rwlock_timedrdlock)
    (pthread_rwlock_t *__rwlock, const struct timespec *);
int (*f_pthread_rwlock_timedwrlock)
    (pthread_rwlock_t *__rwlock, const struct timespec *);
int (*f_pthread_rwlock_tryrdlock)
    (pthread_rwlock_t *__rwlock);
int (*f_pthread_rwlock_trywrlock)
    (pthread_rwlock_t *__rwlock);
int (*f_pthread_rwlock_unlock)
    (pthread_rwlock_t *__rwlock);
int (*f_pthread_rwlock_wrlock)
    (pthread_rwlock_t *__rwlock);
pthread_t (*f_pthread_self)
    (void);
int (*f_pthread_setspecific)
    (pthread_key_t, const void *);
int (*f_pthread_spin_init)
    (pthread_spinlock_t *__spin, int);
int (*f_pthread_spin_destroy)
    (pthread_spinlock_t *__spin);
int (*f_pthread_spin_lock)
    (pthread_spinlock_t *__spin);
int (*f_pthread_spin_trylock)
    (pthread_spinlock_t *__spin);
int (*f_pthread_spin_unlock)
    (pthread_spinlock_t *__spin);
int (*f_pthread_cancel)
    (pthread_t);
int (*f_pthread_setcancelstate)
    (int, int *);
int (*f_pthread_setcanceltype)
    (int, int *);
void (*f_pthread_testcancel)
    (void);
int (*f_pthread_getschedparam)
    (pthread_t pthread, int *, struct sched_param *);
int (*f_pthread_setschedparam)
    (pthread_t, int, const struct sched_param *);
int (*f_pthread_yield)
    (void);
int (*f_pthread_setaffinity_np)
    (pthread_t thread, size_t cpusetsize, const rte_cpuset_t *cpuset);
int (*f_nanosleep)
    (const struct timespec *req, struct timespec *rem);
} _sys_pthread_funcs = {
    .f_pthread_barrier_destroy = NULL,
};


/*
 * this macro obtains the loaded address of a library function
 * and saves it.
 */
static void *__libc_dl_handle = RTLD_NEXT;

#define get_addr_of_loaded_symbol(name) do {                \
    char *error_str;                        \
    _sys_pthread_funcs.f_##name = dlsym(__libc_dl_handle, (#name)); \
    error_str = dlerror();                      \
    if (error_str != NULL) {                    \
        fprintf(stderr, "%s\n", error_str);         \
    }                               \
} while (0)


/*
 * The constructor function initialises the
 * function pointers for pthread library functions
 */
RTE_INIT(pthread_intercept_ctor)
{
    override = 0;
    /*
     * Get the original functions
     */
    get_addr_of_loaded_symbol(pthread_barrier_destroy);
    get_addr_of_loaded_symbol(pthread_barrier_init);
    get_addr_of_loaded_symbol(pthread_barrier_wait);
    get_addr_of_loaded_symbol(pthread_cond_broadcast);
    get_addr_of_loaded_symbol(pthread_cond_destroy);
    get_addr_of_loaded_symbol(pthread_cond_init);
    get_addr_of_loaded_symbol(pthread_cond_signal);
    get_addr_of_loaded_symbol(pthread_cond_timedwait);
    get_addr_of_loaded_symbol(pthread_cond_wait);
    get_addr_of_loaded_symbol(pthread_create);
    get_addr_of_loaded_symbol(pthread_detach);
    get_addr_of_loaded_symbol(pthread_equal);
    get_addr_of_loaded_symbol(pthread_exit);
    get_addr_of_loaded_symbol(pthread_getspecific);
    get_addr_of_loaded_symbol(pthread_getcpuclockid);
    get_addr_of_loaded_symbol(pthread_join);
    get_addr_of_loaded_symbol(pthread_key_create);
    get_addr_of_loaded_symbol(pthread_key_delete);
    get_addr_of_loaded_symbol(pthread_mutex_destroy);
    get_addr_of_loaded_symbol(pthread_mutex_init);
    get_addr_of_loaded_symbol(pthread_mutex_lock);
    get_addr_of_loaded_symbol(pthread_mutex_trylock);
    get_addr_of_loaded_symbol(pthread_mutex_timedlock);
    get_addr_of_loaded_symbol(pthread_mutex_unlock);
    get_addr_of_loaded_symbol(pthread_once);
    get_addr_of_loaded_symbol(pthread_rwlock_destroy);
    get_addr_of_loaded_symbol(pthread_rwlock_init);
    get_addr_of_loaded_symbol(pthread_rwlock_rdlock);
    get_addr_of_loaded_symbol(pthread_rwlock_timedrdlock);
    get_addr_of_loaded_symbol(pthread_rwlock_timedwrlock);
    get_addr_of_loaded_symbol(pthread_rwlock_tryrdlock);
    get_addr_of_loaded_symbol(pthread_rwlock_trywrlock);
    get_addr_of_loaded_symbol(pthread_rwlock_unlock);
    get_addr_of_loaded_symbol(pthread_rwlock_wrlock);
    get_addr_of_loaded_symbol(pthread_self);
    get_addr_of_loaded_symbol(pthread_setspecific);
    get_addr_of_loaded_symbol(pthread_spin_init);
    get_addr_of_loaded_symbol(pthread_spin_destroy);
    get_addr_of_loaded_symbol(pthread_spin_lock);
    get_addr_of_loaded_symbol(pthread_spin_trylock);
    get_addr_of_loaded_symbol(pthread_spin_unlock);
    get_addr_of_loaded_symbol(pthread_cancel);
    get_addr_of_loaded_symbol(pthread_setcancelstate);
    get_addr_of_loaded_symbol(pthread_setcanceltype);
    get_addr_of_loaded_symbol(pthread_testcancel);
    get_addr_of_loaded_symbol(pthread_getschedparam);
    get_addr_of_loaded_symbol(pthread_setschedparam);
    get_addr_of_loaded_symbol(pthread_yield);
    get_addr_of_loaded_symbol(pthread_setaffinity_np);
    get_addr_of_loaded_symbol(nanosleep);
}


/*
 * Enable/Disable pthread override
 * state
 *  0 disable
 *  1 enable
 */
void pthread_override_set(int state)
{
    override = state;
}


/*
 * Return pthread override state
 * return
 *  0 disable
 *  1 enable
 */
int pthread_override_get(void)
{
    return override;
}

/*
 * This macro is used to catch and log
 * invocation of stubs for unimplemented pthread
 * API functions.
 */
#define NOT_IMPLEMENTED do {                \
    if (override) {                 \
        RTE_LOG(WARNING,            \
            PTHREAD_SHIM,           \
            "WARNING %s NOT IMPLEMENTED\n", \
            __func__);          \
    }                       \
} while (0)

/*
 * pthread API override functions follow
 * Note in this example code only a subset of functions are
 * implemented.
 *
 * The stub functions provided will issue a warning log
 * message if an unimplemented function is invoked
 *
 */

int pthread_barrier_destroy(pthread_barrier_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_barrier_destroy(a);
}

int
pthread_barrier_init(pthread_barrier_t *a,
             const pthread_barrierattr_t *b, unsigned c)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_barrier_init(a, b, c);
}

int pthread_barrier_wait(pthread_barrier_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_barrier_wait(a);
}

int pthread_cond_broadcast(pthread_cond_t *cond)
{
    if (override) {

        lthread_cond_broadcast(*(struct lthread_cond **)cond);
        return 0;
    }
    return _sys_pthread_funcs.f_pthread_cond_broadcast(cond);
}

int pthread_mutex_destroy(pthread_mutex_t *mutex)
{
    if (override)
        return lthread_mutex_destroy(*(struct lthread_mutex **)mutex);
    return _sys_pthread_funcs.f_pthread_mutex_destroy(mutex);
}

int pthread_cond_destroy(pthread_cond_t *cond)
{
    if (override)
        return lthread_cond_destroy(*(struct lthread_cond **)cond);
    return _sys_pthread_funcs.f_pthread_cond_destroy(cond);
}

int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr)
{
    if (override)
        return lthread_cond_init(NULL,
                (struct lthread_cond **)cond,
                (const struct lthread_condattr *) attr);
    return _sys_pthread_funcs.f_pthread_cond_init(cond, attr);
}

int pthread_cond_signal(pthread_cond_t *cond)
{
    if (override) {
        lthread_cond_signal(*(struct lthread_cond **)cond);
        return 0;
    }
    return _sys_pthread_funcs.f_pthread_cond_signal(cond);
}

int
pthread_cond_timedwait(pthread_cond_t *__restrict cond,
               pthread_mutex_t *__restrict mutex,
               const struct timespec *__restrict time)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_cond_timedwait(cond, mutex, time);
}

int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
{
    if (override) {
        pthread_mutex_unlock(mutex);
        int rv = lthread_cond_wait(*(struct lthread_cond **)cond, 0);

        pthread_mutex_lock(mutex);
        return rv;
    }
    return _sys_pthread_funcs.f_pthread_cond_wait(cond, mutex);
}

int
pthread_create(pthread_t *__restrict tid,
        const pthread_attr_t *__restrict attr,
        lthread_func_t func,
           void *__restrict arg)
{
    if (override) {
        int lcore = -1;

        if (attr != NULL) {
            /* determine CPU being requested */
            rte_cpuset_t cpuset;

            CPU_ZERO(&cpuset);
            pthread_attr_getaffinity_np(attr,
                        sizeof(rte_cpuset_t),
                        &cpuset);

            if (CPU_COUNT(&cpuset) != 1)
                return POSIX_ERRNO(EINVAL);

            for (lcore = 0; lcore < LTHREAD_MAX_LCORES; lcore++) {
                if (!CPU_ISSET(lcore, &cpuset))
                    continue;
                break;
            }
        }
        return lthread_create((struct lthread **)tid, lcore,
                      func, arg);
    }
    return _sys_pthread_funcs.f_pthread_create(tid, attr, func, arg);
}

int pthread_detach(pthread_t tid)
{
    if (override) {
        struct lthread *lt = (struct lthread *)tid;

        if (lt == lthread_current()) {
            lthread_detach();
            return 0;
        }
        NOT_IMPLEMENTED;
    }
    return _sys_pthread_funcs.f_pthread_detach(tid);
}

int pthread_equal(pthread_t a, pthread_t b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_equal(a, b);
}

void pthread_exit_override(void *v)
{
    if (override) {
        lthread_exit(v);
        return;
    }
    _sys_pthread_funcs.f_pthread_exit(v);
}

void
*pthread_getspecific(pthread_key_t key)
{
    if (override)
        return lthread_getspecific((unsigned int) key);
    return _sys_pthread_funcs.f_pthread_getspecific(key);
}

int pthread_getcpuclockid(pthread_t a, clockid_t *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_getcpuclockid(a, b);
}

int pthread_join(pthread_t tid, void **val)
{
    if (override)
        return lthread_join((struct lthread *)tid, val);
    return _sys_pthread_funcs.f_pthread_join(tid, val);
}

int pthread_key_create(pthread_key_t *keyptr, void (*dtor) (void *))
{
    if (override)
        return lthread_key_create((unsigned int *)keyptr, dtor);
    return _sys_pthread_funcs.f_pthread_key_create(keyptr, dtor);
}

int pthread_key_delete(pthread_key_t key)
{
    if (override) {
        lthread_key_delete((unsigned int) key);
        return 0;
    }
    return _sys_pthread_funcs.f_pthread_key_delete(key);
}


int
pthread_mutex_init(pthread_mutex_t *mutex, const pthread_mutexattr_t *attr)
{
    if (override)
        return lthread_mutex_init(NULL,
                (struct lthread_mutex **)mutex,
                (const struct lthread_mutexattr *)attr);
    return _sys_pthread_funcs.f_pthread_mutex_init(mutex, attr);
}

int pthread_mutex_lock(pthread_mutex_t *mutex)
{
    if (override)
        return lthread_mutex_lock(*(struct lthread_mutex **)mutex);
    return _sys_pthread_funcs.f_pthread_mutex_lock(mutex);
}

int pthread_mutex_trylock(pthread_mutex_t *mutex)
{
    if (override)
        return lthread_mutex_trylock(*(struct lthread_mutex **)mutex);
    return _sys_pthread_funcs.f_pthread_mutex_trylock(mutex);
}

int pthread_mutex_timedlock(pthread_mutex_t *mutex, const struct timespec *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_mutex_timedlock(mutex, b);
}

int pthread_mutex_unlock(pthread_mutex_t *mutex)
{
    if (override)
        return lthread_mutex_unlock(*(struct lthread_mutex **)mutex);
    return _sys_pthread_funcs.f_pthread_mutex_unlock(mutex);
}

int pthread_once(pthread_once_t *a, void (b) (void))
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_once(a, b);
}

int pthread_rwlock_destroy(pthread_rwlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_destroy(a);
}

int pthread_rwlock_init(pthread_rwlock_t *a, const pthread_rwlockattr_t *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_init(a, b);
}

int pthread_rwlock_rdlock(pthread_rwlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_rdlock(a);
}

int pthread_rwlock_timedrdlock(pthread_rwlock_t *a, const struct timespec *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_timedrdlock(a, b);
}

int pthread_rwlock_timedwrlock(pthread_rwlock_t *a, const struct timespec *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_timedwrlock(a, b);
}

int pthread_rwlock_tryrdlock(pthread_rwlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_tryrdlock(a);
}

int pthread_rwlock_trywrlock(pthread_rwlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_trywrlock(a);
}

int pthread_rwlock_unlock(pthread_rwlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_unlock(a);
}

int pthread_rwlock_wrlock(pthread_rwlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_rwlock_wrlock(a);
}

#ifdef RTE_EXEC_ENV_LINUXAPP
int
pthread_yield(void)
{
    if (override) {
        lthread_yield();
        return 0;
    }
    return _sys_pthread_funcs.f_pthread_yield();
}
#else
void
pthread_yield(void)
{
    if (override)
        lthread_yield();
    else
        _sys_pthread_funcs.f_pthread_yield();
}
#endif

pthread_t pthread_self(void)
{
    if (override)
        return (pthread_t) lthread_current();
    return _sys_pthread_funcs.f_pthread_self();
}

int pthread_setspecific(pthread_key_t key, const void *data)
{
    if (override) {
        int rv =  lthread_setspecific((unsigned int)key, data);
        return rv;
    }
    return _sys_pthread_funcs.f_pthread_setspecific(key, data);
}

int pthread_spin_init(pthread_spinlock_t *a, int b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_spin_init(a, b);
}

int pthread_spin_destroy(pthread_spinlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_spin_destroy(a);
}

int pthread_spin_lock(pthread_spinlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_spin_lock(a);
}

int pthread_spin_trylock(pthread_spinlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_spin_trylock(a);
}

int pthread_spin_unlock(pthread_spinlock_t *a)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_spin_unlock(a);
}

int pthread_cancel(pthread_t tid)
{
    if (override) {
        lthread_cancel(*(struct lthread **)tid);
        return 0;
    }
    return _sys_pthread_funcs.f_pthread_cancel(tid);
}

int pthread_setcancelstate(int a, int *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_setcancelstate(a, b);
}

int pthread_setcanceltype(int a, int *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_setcanceltype(a, b);
}

void pthread_testcancel(void)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_testcancel();
}


int pthread_getschedparam(pthread_t tid, int *a, struct sched_param *b)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_getschedparam(tid, a, b);
}

int pthread_setschedparam(pthread_t a, int b, const struct sched_param *c)
{
    NOT_IMPLEMENTED;
    return _sys_pthread_funcs.f_pthread_setschedparam(a, b, c);
}


int nanosleep(const struct timespec *req, struct timespec *rem)
{
    if (override) {
        uint64_t ns = req->tv_sec * 1000000000 + req->tv_nsec;

        lthread_sleep(ns);
        return 0;
    }
    return _sys_pthread_funcs.f_nanosleep(req, rem);
}

int
pthread_setaffinity_np(pthread_t thread, size_t cpusetsize,
               const rte_cpuset_t *cpuset)
{
    if (override) {
        /* we only allow affinity with a single CPU */
        if (CPU_COUNT(cpuset) != 1)
            return POSIX_ERRNO(EINVAL);

        /* we only allow the current thread to sets its own affinity */
        struct lthread *lt = (struct lthread *)thread;

        if (lthread_current() != lt)
            return POSIX_ERRNO(EINVAL);

        /* determine the CPU being requested */
        int i;

        for (i = 0; i < LTHREAD_MAX_LCORES; i++) {
            if (!CPU_ISSET(i, cpuset))
                continue;
            break;
        }
        /* check requested core is allowed */
        if (i == LTHREAD_MAX_LCORES)
            return POSIX_ERRNO(EINVAL);

        /* finally we can set affinity to the requested lcore */
        lthread_set_affinity(i);
        return 0;
    }
    return _sys_pthread_funcs.f_pthread_setaffinity_np(thread, cpusetsize,
                               cpuset);
}