static struct zdoor_result *
zdoor_cb(struct zdoor_cookie *cookie, char *argp, size_t argp_sz)
{
struct door *d;
struct req *r;
ErlNifEnv *env = enif_alloc_env();
/* we kept the struct door in the biscuit */
d = (struct door *)cookie->zdc_biscuit;
/* this request */
r = req_alloc();
/* take the rlist lock first, then the req lock */
enif_rwlock_rwlock(d->rlock);
enif_mutex_lock(r->lock);
req_insert(d, r);
enif_rwlock_rwunlock(d->rlock);
/* make the request into a binary term to put it into enif_send() */
ErlNifBinary bin;
enif_alloc_binary(argp_sz, &bin);
memcpy(bin.data, argp, argp_sz);
ERL_NIF_TERM binTerm = enif_make_binary(env, &bin);
/* send a message back to the session owner */
enif_send(NULL, &d->owner, env,
enif_make_tuple3(env,
enif_make_atom(env, "zdoor"),
enif_make_resource(env, r),
binTerm));
/* now wait until the request has been replied to */
enif_cond_wait(r->cond, r->lock);
/* convert the reply into a zdoor_result */
/* we have to use naked malloc() since libzdoor will use free() */
struct zdoor_result *res = malloc(sizeof(struct zdoor_result));
res->zdr_size = r->replen;
res->zdr_data = r->rep;
r->rep = NULL;
r->replen = 0;
/* yes, we have to unlock and re-lock to avoid lock inversion here */
enif_mutex_unlock(r->lock);
/* remove and free the struct req */
enif_rwlock_rwlock(d->rlock);
enif_mutex_lock(r->lock);
req_remove(d, r);
enif_rwlock_rwunlock(d->rlock);
req_free(r);
enif_free_env(env);
return res;
}
static void
unload_cb(ErlNifEnv *env, void *priv_data)
{
struct atom_node *an;
enif_rwlock_rwlock(gbl->atom_lock);
/* when we unload, we want to tell all of the active caches to die,
then join() their bg_threads to wait until they're completely gone */
while ((an = RB_MIN(atom_tree, &(gbl->atom_head)))) {
struct cache *c = an->cache;
enif_rwlock_rwunlock(gbl->atom_lock);
enif_mutex_lock(c->ctrl_lock);
c->flags |= FL_DYING;
enif_mutex_unlock(c->ctrl_lock);
enif_cond_broadcast(c->check_cond);
enif_thread_join(c->bg_thread, NULL);
enif_rwlock_rwlock(gbl->atom_lock);
}
enif_rwlock_rwunlock(gbl->atom_lock);
enif_rwlock_destroy(gbl->atom_lock);
enif_clear_env(gbl->atom_env);
enif_free(gbl);
gbl = NULL;
}
/* destroy(Cache :: atom()) -- destroys and entire cache
destroy(Cache :: atom(), Key :: binary()) -- removes an entry
from a cache */
static ERL_NIF_TERM
destroy(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
{
ERL_NIF_TERM atom;
struct cache *c;
ErlNifBinary kbin;
struct cache_node *n;
if (!enif_is_atom(env, argv[0]))
return enif_make_badarg(env);
atom = argv[0];
if ((c = get_cache(atom))) {
if (argc == 2) {
if (!enif_inspect_binary(env, argv[1], &kbin))
return enif_make_badarg(env);
enif_rwlock_rwlock(c->cache_lock);
enif_rwlock_rwlock(c->lookup_lock);
HASH_FIND(hh, c->lookup, kbin.data, kbin.size, n);
if (!n) {
enif_rwlock_rwunlock(c->lookup_lock);
enif_rwlock_rwunlock(c->cache_lock);
return enif_make_atom(env, "notfound");
}
enif_mutex_lock(c->ctrl_lock);
destroy_cache_node(n);
enif_mutex_unlock(c->ctrl_lock);
enif_rwlock_rwunlock(c->lookup_lock);
enif_rwlock_rwunlock(c->cache_lock);
enif_consume_timeslice(env, 50);
return enif_make_atom(env, "ok");
} else {
enif_mutex_lock(c->ctrl_lock);
c->flags |= FL_DYING;
enif_mutex_unlock(c->ctrl_lock);
enif_cond_broadcast(c->check_cond);
enif_thread_join(c->bg_thread, NULL);
enif_consume_timeslice(env, 100);
return enif_make_atom(env, "ok");
}
return enif_make_atom(env, "ok");
}
return enif_make_atom(env, "notfound");
}
static ERL_NIF_TERM robin_q_set(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
robin_q_handle *handle = NULL;
if (enif_get_resource(env, argv[0], robin_q_RESOURCE, (void**)&handle) == 0) {
return enif_make_badarg(env);
}
enif_rwlock_rwlock(handle->lock);
enif_clear_env(handle->env);
do_set(handle, argv[1]);
enif_rwlock_rwunlock(handle->lock);
return enif_make_atom(env, "ok");
}
static INLINE void locking(int mode, ErlNifRWLock* lock)
{
switch (mode) {
case CRYPTO_LOCK|CRYPTO_READ:
enif_rwlock_rlock(lock);
break;
case CRYPTO_LOCK|CRYPTO_WRITE:
enif_rwlock_rwlock(lock);
break;
case CRYPTO_UNLOCK|CRYPTO_READ:
enif_rwlock_runlock(lock);
break;
case CRYPTO_UNLOCK|CRYPTO_WRITE:
enif_rwlock_rwunlock(lock);
break;
default:
ASSERT(!"Invalid lock mode");
}
}
/* create(Cache :: atom(), MaxSize :: integer(), MinQ1Size :: integer()) */
static ERL_NIF_TERM
create(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
{
ERL_NIF_TERM atom;
ErlNifUInt64 max_size, min_q1_size;
struct cache *c;
if (!enif_is_atom(env, argv[0]))
return enif_make_badarg(env);
atom = argv[0];
if (!enif_get_uint64(env, argv[1], &max_size))
return enif_make_badarg(env);
if (!enif_get_uint64(env, argv[2], &min_q1_size))
return enif_make_badarg(env);
if ((c = get_cache(atom))) {
ERL_NIF_TERM ret = enif_make_atom(env, "already_exists");
enif_consume_timeslice(env, 5);
enif_rwlock_rwlock(c->cache_lock);
/* expansion is safe because we don't have to engage the background
thread and won't cause sudden eviction pressure
TODO: a nice way to shrink the cache without seizing it up */
if (c->max_size < max_size && c->min_q1_size < min_q1_size) {
c->max_size = max_size;
c->min_q1_size = min_q1_size;
enif_rwlock_rwunlock(c->cache_lock);
ret = enif_make_atom(env, "ok");
enif_consume_timeslice(env, 10);
} else {
enif_rwlock_rwunlock(c->cache_lock);
}
return ret;
} else {
c = new_cache(atom, max_size, min_q1_size);
enif_consume_timeslice(env, 20);
return enif_make_atom(env, "ok");
}
}
static struct cache *
new_cache(ERL_NIF_TERM atom, int max_size, int min_q1_size)
{
struct cache *c;
struct atom_node *an;
int i;
c = enif_alloc(sizeof(*c));
memset(c, 0, sizeof(*c));
c->max_size = max_size;
c->min_q1_size = min_q1_size;
c->lookup_lock = enif_rwlock_create("cache->lookup_lock");
c->cache_lock = enif_rwlock_create("cache->cache_lock");
c->ctrl_lock = enif_mutex_create("cache->ctrl_lock");
c->check_cond = enif_cond_create("cache->check_cond");
TAILQ_INIT(&(c->q1.head));
TAILQ_INIT(&(c->q2.head));
for (i = 0; i < N_INCR_BKT; ++i) {
TAILQ_INIT(&(c->incr_head[i]));
c->incr_lock[i] = enif_mutex_create("cache->incr_lock");
}
RB_INIT(&(c->expiry_head));
an = enif_alloc(sizeof(*an));
memset(an, 0, sizeof(*an));
an->atom = enif_make_copy(gbl->atom_env, atom);
an->cache = c;
c->atom_node = an;
enif_rwlock_rwlock(gbl->atom_lock);
RB_INSERT(atom_tree, &(gbl->atom_head), an);
/* start the background thread for the cache. after this, the bg thread now
owns the cache and all its data and will free it at exit */
enif_thread_create("cachethread", &(c->bg_thread), cache_bg_thread, c, NULL);
enif_rwlock_rwunlock(gbl->atom_lock);
return c;
}
static ERL_NIF_TERM cqueue_register(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) {
ErlNifTid thread_id = enif_thread_self();
unsigned int i = 0;
enif_rwlock_rwlock(lookup_lock);
for (i = 0; i < schedulers; ++i) {
if (scheduler_ids[i] == thread_id) {
printf("Scheduler (%p) already registered.\r\n", thread_id);
break;
} else if (scheduler_ids[i] == NULL) {
printf("Registering scheduler (%p) with index %d\r\n", thread_id, i);
scheduler_ids[i] = thread_id;
break;
}
}
enif_rwlock_rwunlock(lookup_lock);
if (i == schedulers) {
return enif_make_badarg(env);
} else {
return enif_make_atom(env, "ok");
}
}
static ERL_NIF_TERM
put(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
{
ERL_NIF_TERM atom;
ErlNifBinary kbin, vbin;
struct cache *c;
struct cache_node *n, *ng;
ErlNifUInt64 lifetime = 0;
if (!enif_is_atom(env, argv[0]))
return enif_make_badarg(env);
atom = argv[0];
if (!enif_inspect_binary(env, argv[1], &kbin))
return enif_make_badarg(env);
if (!enif_inspect_binary(env, argv[2], &vbin))
return enif_make_badarg(env);
if ((c = get_cache(atom))) {
enif_consume_timeslice(env, 1);
} else {
/* if we've been asked to put() in to a cache that doesn't exist yet
then we should create it! */
ErlNifUInt64 max_size, min_q1_size;
if (!enif_get_uint64(env, argv[3], &max_size))
return enif_make_badarg(env);
if (!enif_get_uint64(env, argv[4], &min_q1_size))
return enif_make_badarg(env);
c = new_cache(atom, max_size, min_q1_size);
enif_consume_timeslice(env, 20);
}
if (argc > 5)
if (!enif_get_uint64(env, argv[5], &lifetime))
return enif_make_badarg(env);
n = enif_alloc(sizeof(*n));
memset(n, 0, sizeof(*n));
n->c = c;
n->vsize = vbin.size;
n->ksize = kbin.size;
n->size = vbin.size + kbin.size;
n->key = enif_alloc(kbin.size);
memcpy(n->key, kbin.data, kbin.size);
n->val = enif_alloc_resource(value_type, vbin.size);
memcpy(n->val, vbin.data, vbin.size);
n->q = &(c->q1);
if (lifetime) {
clock_now(&(n->expiry));
n->expiry.tv_sec += lifetime;
}
enif_rwlock_rwlock(c->cache_lock);
enif_rwlock_rwlock(c->lookup_lock);
HASH_FIND(hh, c->lookup, kbin.data, kbin.size, ng);
if (ng) {
enif_mutex_lock(c->ctrl_lock);
destroy_cache_node(ng);
enif_mutex_unlock(c->ctrl_lock);
}
TAILQ_INSERT_HEAD(&(c->q1.head), n, entry);
c->q1.size += n->size;
HASH_ADD_KEYPTR(hh, c->lookup, n->key, n->ksize, n);
if (lifetime) {
struct cache_node *rn;
rn = RB_INSERT(expiry_tree, &(c->expiry_head), n);
/* it's possible to get two timestamps that are the same, if this happens
just bump us forwards by 1 usec until we're unique */
while (rn != NULL) {
++(n->expiry.tv_nsec);
rn = RB_INSERT(expiry_tree, &(c->expiry_head), n);
}
}
enif_rwlock_rwunlock(c->lookup_lock);
enif_rwlock_rwunlock(c->cache_lock);
enif_cond_broadcast(c->check_cond);
enif_consume_timeslice(env, 50);
return enif_make_atom(env, "ok");
}
static void *
cache_bg_thread(void *arg)
{
struct cache *c = (struct cache *)arg;
int i, dud;
while (1) {
enif_mutex_lock(c->ctrl_lock);
/* if we've been told to die, quit this loop and start cleaning up */
if (c->flags & FL_DYING) {
enif_mutex_unlock(c->ctrl_lock);
break;
}
/* sleep until there is work to do */
enif_cond_wait(c->check_cond, c->ctrl_lock);
__sync_add_and_fetch(&(c->wakeups), 1);
dud = 1;
/* we have to let go of ctrl_lock so we can take cache_lock then
ctrl_lock again to get them back in the right order */
enif_mutex_unlock(c->ctrl_lock);
enif_rwlock_rwlock(c->cache_lock);
enif_mutex_lock(c->ctrl_lock);
/* first process the promotion queue before we do any evicting */
for (i = 0; i < N_INCR_BKT; ++i) {
enif_mutex_lock(c->incr_lock[i]);
while (!TAILQ_EMPTY(&(c->incr_head[i]))) {
struct cache_incr_node *n;
n = TAILQ_FIRST(&(c->incr_head[i]));
TAILQ_REMOVE(&(c->incr_head[i]), n, entry);
__sync_sub_and_fetch(&(c->incr_count), 1);
dud = 0;
/* let go of the ctrl_lock here, we don't need it when we aren't looking
at the incr_queue, and this way other threads can use it while we shuffle
queue nodes around */
enif_mutex_unlock(c->incr_lock[i]);
enif_mutex_unlock(c->ctrl_lock);
if (n->node->q == &(c->q1)) {
TAILQ_REMOVE(&(c->q1.head), n->node, entry);
c->q1.size -= n->node->size;
TAILQ_INSERT_HEAD(&(c->q2.head), n->node, entry);
n->node->q = &(c->q2);
c->q2.size += n->node->size;
} else if (n->node->q == &(c->q2)) {
TAILQ_REMOVE(&(c->q2.head), n->node, entry);
TAILQ_INSERT_HEAD(&(c->q2.head), n->node, entry);
}
enif_free(n);
/* take the ctrl_lock back again for the next loop around */
enif_mutex_lock(c->ctrl_lock);
enif_mutex_lock(c->incr_lock[i]);
}
enif_mutex_unlock(c->incr_lock[i]);
}
/* let go of the ctrl_lock here for two reasons:
1. avoid lock inversion, because if we have evictions to do we
will need to take lookup_lock, and we must take lookup_lock
before taking ctrl_lock
2. if we don't need to do evictions, we're done with the structures
that are behind ctrl_lock so we should give it up for others */
enif_mutex_unlock(c->ctrl_lock);
/* do timed evictions -- if anything has expired, nuke it */
{
struct cache_node *n;
if ((n = RB_MIN(expiry_tree, &(c->expiry_head)))) {
struct timespec now;
clock_now(&now);
while (n && n->expiry.tv_sec < now.tv_sec) {
enif_mutex_lock(c->ctrl_lock);
dud = 0;
destroy_cache_node(n);
enif_mutex_unlock(c->ctrl_lock);
n = RB_MIN(expiry_tree, &(c->expiry_head));
}
}
}
/* now check if we need to do ordinary size limit evictions */
if (c->q1.size + c->q2.size > c->max_size) {
enif_rwlock_rwlock(c->lookup_lock);
enif_mutex_lock(c->ctrl_lock);
while ((c->q1.size + c->q2.size > c->max_size) &&
(c->q1.size > c->min_q1_size)) {
struct cache_node *n;
n = TAILQ_LAST(&(c->q1.head), cache_q);
destroy_cache_node(n);
}
while (c->q1.size + c->q2.size > c->max_size) {
struct cache_node *n;
n = TAILQ_LAST(&(c->q2.head), cache_q);
destroy_cache_node(n);
}
dud = 0;
enif_mutex_unlock(c->ctrl_lock);
enif_rwlock_rwunlock(c->lookup_lock);
}
if (dud)
__sync_add_and_fetch(&(c->dud_wakeups), 1);
/* now let go of the cache_lock that we took right back at the start of
this iteration */
enif_rwlock_rwunlock(c->cache_lock);
}
/* first remove us from the atom_tree, so we get no new operations coming in */
enif_rwlock_rwlock(gbl->atom_lock);
RB_REMOVE(atom_tree, &(gbl->atom_head), c->atom_node);
enif_rwlock_rwunlock(gbl->atom_lock);
enif_free(c->atom_node);
/* now take all of our locks, to make sure any pending operations are done */
enif_rwlock_rwlock(c->cache_lock);
enif_rwlock_rwlock(c->lookup_lock);
enif_mutex_lock(c->ctrl_lock);
c->atom_node = NULL;
/* free the actual cache queues */
{
struct cache_node *n, *nextn;
nextn = TAILQ_FIRST(&(c->q1.head));
while ((n = nextn)) {
nextn = TAILQ_NEXT(n, entry);
destroy_cache_node(n);
}
nextn = TAILQ_FIRST(&(c->q2.head));
while ((n = nextn)) {
nextn = TAILQ_NEXT(n, entry);
destroy_cache_node(n);
}
}
for (i = 0; i < N_INCR_BKT; ++i)
enif_mutex_lock(c->incr_lock[i]);
/* free the incr_queue */
for (i = 0; i < N_INCR_BKT; ++i) {
struct cache_incr_node *in, *nextin;
nextin = TAILQ_FIRST(&(c->incr_head[i]));
while ((in = nextin)) {
nextin = TAILQ_NEXT(in, entry);
TAILQ_REMOVE(&(c->incr_head[i]), in, entry);
in->node = 0;
enif_free(in);
}
enif_mutex_unlock(c->incr_lock[i]);
enif_mutex_destroy(c->incr_lock[i]);
}
/* unlock and destroy! */
enif_cond_destroy(c->check_cond);
enif_mutex_unlock(c->ctrl_lock);
enif_mutex_destroy(c->ctrl_lock);
enif_rwlock_rwunlock(c->lookup_lock);
enif_rwlock_destroy(c->lookup_lock);
enif_rwlock_rwunlock(c->cache_lock);
enif_rwlock_destroy(c->cache_lock);
enif_free(c);
return 0;
}
/* the async job thread that handles opening/closing of doors */
void *
job_thread(void *arg)
{
struct zdoor_handle *zhandle;
int cont = 1;
int res;
/* first init the handle */
zhandle = zdoor_handle_init();
enif_mutex_lock(gbl.jlock);
while (cont) {
struct job *j;
while (!gbl.jlist)
enif_cond_wait(gbl.jcond, gbl.jlock);
j = gbl.jlist;
while (j) {
gbl.jlist = j->next;
enif_mutex_unlock(gbl.jlock);
if (j->action == ACT_OPEN) {
enif_rwlock_rwlock(gbl.dlock);
j->door->next = NULL;
if (gbl.dlist != NULL)
j->door->next = gbl.dlist;
gbl.dlist = j->door;
enif_rwlock_rwunlock(gbl.dlock);
res = zdoor_open(zhandle, j->door->zonename, j->door->service, j->door, zdoor_cb);
ErlNifEnv *env = enif_alloc_env();
ERL_NIF_TERM ret = enif_make_atom(env, "ok");
switch (res) {
case ZDOOR_ERROR:
ret = enif_make_atom(env, "error");
break;
case ZDOOR_NOT_GLOBAL_ZONE:
ret = enif_make_atom(env, "not_global");
break;
case ZDOOR_ZONE_NOT_RUNNING:
ret = enif_make_atom(env, "not_running");
break;
case ZDOOR_ZONE_FORBIDDEN:
ret = enif_make_atom(env, "eperm");
break;
case ZDOOR_ARGS_ERROR:
ret = enif_make_atom(env, "badarg");
break;
case ZDOOR_OUT_OF_MEMORY:
ret = enif_make_atom(env, "enomem");
break;
}
enif_send(NULL, &j->owner, env,
enif_make_tuple3(env,
enif_make_atom(env, "zdoor_job"),
enif_make_atom(env, "open"),
ret));
enif_free_env(env);
} else if (j->action == ACT_CLOSE) {
enif_rwlock_rwlock(gbl.dlock);
enif_rwlock_rwlock(j->door->rlock);
if (j->door->rlist) {
enif_rwlock_rwunlock(j->door->rlock);
enif_rwlock_rwunlock(gbl.dlock);
ErlNifEnv *env = enif_alloc_env();
enif_send(NULL, &j->owner, env,
enif_make_tuple3(env,
enif_make_atom(env, "zdoor_job"),
enif_make_atom(env, "close"),
enif_make_atom(env, "busy")));
enif_free_env(env);
} else {
struct door *d = gbl.dlist;
if (d == j->door) {
gbl.dlist = j->door->next;
} else {
for (; d; d = d->next) {
if (d->next == j->door) break;
}
if (d)
d->next = j->door->next;
}
enif_rwlock_rwunlock(gbl.dlock);
zdoor_close(zhandle, j->door->zonename, j->door->service);
door_free(j->door);
ErlNifEnv *env = enif_alloc_env();
enif_send(NULL, &j->owner, env,
enif_make_tuple3(env,
enif_make_atom(env, "zdoor_job"),
enif_make_atom(env, "close"),
enif_make_atom(env, "ok")));
enif_free_env(env);
}
} else if (j->action == ACT_QUIT) {
cont = 0;
}
enif_free(j);
enif_mutex_lock(gbl.jlock);
j = gbl.jlist;
}
}
enif_mutex_unlock(gbl.jlock);
zdoor_handle_destroy(zhandle);
return NULL;
}