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authorRickard Green <[email protected]>2014-08-26 17:26:31 +0200
committerRickard Green <[email protected]>2014-09-25 16:42:20 +0200
commit6084a42a24fca52a5de2bc487c0cd2be46dcc21f (patch)
tree63fe33c074ccce7dd8bf51e846b9b778b81e4af5 /erts/emulator/sys/common
parent65e335e255cb76d979f605ed34700e4e02041139 (diff)
downloadotp-6084a42a24fca52a5de2bc487c0cd2be46dcc21f.tar.gz
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Introduce support for eager check I/O scheduling
Diffstat (limited to 'erts/emulator/sys/common')
-rw-r--r--erts/emulator/sys/common/erl_check_io.c694
-rw-r--r--erts/emulator/sys/common/erl_check_io.h45
-rw-r--r--erts/emulator/sys/common/erl_sys_common_misc.c8
3 files changed, 651 insertions, 96 deletions
diff --git a/erts/emulator/sys/common/erl_check_io.c b/erts/emulator/sys/common/erl_check_io.c
index 7035dc77df..e62f34b679 100644
--- a/erts/emulator/sys/common/erl_check_io.c
+++ b/erts/emulator/sys/common/erl_check_io.c
@@ -51,8 +51,17 @@ typedef char EventStateType;
#define ERTS_EV_TYPE_STOP_USE ((EventStateType) 3) /* pending stop_select */
typedef char EventStateFlags;
-#define ERTS_EV_FLAG_USED ((EventStateFlags) 1) /* ERL_DRV_USE has been turned on */
+#define ERTS_EV_FLAG_USED ((EventStateFlags) 1) /* ERL_DRV_USE has been turned on */
+#define ERTS_EV_FLAG_DEFER_IN_EV ((EventStateFlags) 2)
+#define ERTS_EV_FLAG_DEFER_OUT_EV ((EventStateFlags) 4)
+#ifdef DEBUG
+# define ERTS_ACTIVE_FD_INC 2
+#else
+# define ERTS_ACTIVE_FD_INC 128
+#endif
+
+#define ERTS_CHECK_IO_POLL_RES_LEN 512
#if defined(ERTS_KERNEL_POLL_VERSION)
# define ERTS_CIO_EXPORT(FUNC) FUNC ## _kp
@@ -66,6 +75,7 @@ typedef char EventStateFlags;
(ERTS_POLL_USE_POLL && !ERTS_POLL_USE_KERNEL_POLL)
#define ERTS_CIO_POLL_CTL ERTS_POLL_EXPORT(erts_poll_control)
+#define ERTS_CIO_POLL_CTLV ERTS_POLL_EXPORT(erts_poll_controlv)
#define ERTS_CIO_POLL_WAIT ERTS_POLL_EXPORT(erts_poll_wait)
#ifdef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
#define ERTS_CIO_POLL_AS_INTR ERTS_POLL_EXPORT(erts_poll_async_sig_interrupt)
@@ -82,6 +92,13 @@ static struct pollset_info
{
ErtsPollSet ps;
erts_smp_atomic_t in_poll_wait; /* set while doing poll */
+ struct {
+ int six; /* start index */
+ int eix; /* end index */
+ erts_smp_atomic32_t no;
+ int size;
+ ErtsSysFdType *array;
+ } active_fd;
#ifdef ERTS_SMP
struct removed_fd* removed_list; /* list of deselected fd's*/
erts_smp_spinlock_t removed_list_lock;
@@ -94,9 +111,11 @@ typedef struct {
SafeHashBucket hb;
#endif
ErtsSysFdType fd;
- union {
- ErtsDrvEventDataState *event; /* ERTS_EV_TYPE_DRV_EV */
+ struct {
ErtsDrvSelectDataState *select; /* ERTS_EV_TYPE_DRV_SEL */
+#if ERTS_CIO_HAVE_DRV_EVENT
+ ErtsDrvEventDataState *event; /* ERTS_EV_TYPE_DRV_EV */
+#endif
erts_driver_t* drv_ptr; /* ERTS_EV_TYPE_STOP_USE */
} driver;
ErtsPollEvents events;
@@ -166,6 +185,10 @@ static ERTS_INLINE ErtsDrvEventState* hash_new_drv_ev_state(ErtsSysFdType fd)
ErtsDrvEventState tmpl;
tmpl.fd = fd;
tmpl.driver.select = NULL;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ tmpl.driver.event = NULL;
+#endif
+ tmpl.driver.drv_ptr = NULL;
tmpl.events = 0;
tmpl.remove_cnt = 0;
tmpl.type = ERTS_EV_TYPE_NONE;
@@ -206,6 +229,65 @@ ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(removed_fd, struct removed_fd, 64, ERTS_ALC_T_F
#endif
static ERTS_INLINE void
+init_iotask(ErtsIoTask *io_task)
+{
+ erts_port_task_handle_init(&io_task->task);
+ erts_smp_atomic_init_nob(&io_task->executed_time, ~((erts_aint_t) 0));
+}
+
+static ERTS_INLINE int
+is_iotask_active(ErtsIoTask *io_task, erts_aint_t current_cio_time)
+{
+ if (erts_port_task_is_scheduled(&io_task->task))
+ return 1;
+ if (erts_smp_atomic_read_nob(&io_task->executed_time) == current_cio_time)
+ return 1;
+ return 0;
+}
+
+static ERTS_INLINE ErtsDrvSelectDataState *
+alloc_drv_select_data(void)
+{
+ ErtsDrvSelectDataState *dsp = erts_alloc(ERTS_ALC_T_DRV_SEL_D_STATE,
+ sizeof(ErtsDrvSelectDataState));
+ dsp->inport = NIL;
+ dsp->outport = NIL;
+ init_iotask(&dsp->iniotask);
+ init_iotask(&dsp->outiotask);
+ return dsp;
+}
+
+static ERTS_INLINE void
+free_drv_select_data(ErtsDrvSelectDataState *dsp)
+{
+ ASSERT(!erts_port_task_is_scheduled(&dsp->iniotask.task));
+ ASSERT(!erts_port_task_is_scheduled(&dsp->outiotask.task));
+ erts_free(ERTS_ALC_T_DRV_SEL_D_STATE, dsp);
+}
+
+static ERTS_INLINE ErtsDrvEventDataState *
+alloc_drv_event_data(void)
+{
+ ErtsDrvEventDataState *dep = erts_alloc(ERTS_ALC_T_DRV_EV_D_STATE,
+ sizeof(ErtsDrvEventDataState));
+ dep->port = NIL;
+ dep->data = NULL;
+ dep->removed_events = 0;
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ dep->deferred_events = 0;
+#endif
+ init_iotask(&dep->iotask);
+ return dep;
+}
+
+static ERTS_INLINE void
+free_drv_event_data(ErtsDrvEventDataState *dep)
+{
+ ASSERT(!erts_port_task_is_scheduled(&dep->iotask.task));
+ erts_free(ERTS_ALC_T_DRV_EV_D_STATE, dep);
+}
+
+static ERTS_INLINE void
remember_removed(ErtsDrvEventState *state, struct pollset_info* psi)
{
#ifdef ERTS_SMP
@@ -285,7 +367,7 @@ forget_removed(struct pollset_info* psi)
drv_ptr = state->driver.drv_ptr;
ASSERT(drv_ptr);
state->type = ERTS_EV_TYPE_NONE;
- state->flags = 0;
+ state->flags &= ~ERTS_EV_FLAG_USED;
state->driver.drv_ptr = NULL;
/* Fall through */
case ERTS_EV_TYPE_NONE:
@@ -342,6 +424,10 @@ grow_drv_ev_state(int min_ix)
for (i = erts_smp_atomic_read_nob(&drv_ev_state_len); i < new_len; i++) {
drv_ev_state[i].fd = (ErtsSysFdType) i;
drv_ev_state[i].driver.select = NULL;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ drv_ev_state[i].driver.event = NULL;
+#endif
+ drv_ev_state[i].driver.drv_ptr = NULL;
drv_ev_state[i].events = 0;
drv_ev_state[i].remove_cnt = 0;
drv_ev_state[i].type = ERTS_EV_TYPE_NONE;
@@ -362,11 +448,7 @@ grow_drv_ev_state(int min_ix)
static ERTS_INLINE void
abort_task(Eterm id, ErtsPortTaskHandle *pthp, EventStateType type)
{
- if (is_nil(id)) {
- ASSERT(type == ERTS_EV_TYPE_NONE
- || !erts_port_task_is_scheduled(pthp));
- }
- else if (erts_port_task_is_scheduled(pthp)) {
+ if (is_not_nil(id) && erts_port_task_is_scheduled(pthp)) {
erts_port_task_abort(pthp);
ASSERT(erts_is_port_alive(id));
}
@@ -381,7 +463,7 @@ abort_tasks(ErtsDrvEventState *state, int mode)
#if ERTS_CIO_HAVE_DRV_EVENT
case ERTS_EV_TYPE_DRV_EV:
abort_task(state->driver.event->port,
- &state->driver.event->task,
+ &state->driver.event->iotask.task,
ERTS_EV_TYPE_DRV_EV);
return;
#endif
@@ -395,14 +477,14 @@ abort_tasks(ErtsDrvEventState *state, int mode)
case ERL_DRV_WRITE:
ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL);
abort_task(state->driver.select->outport,
- &state->driver.select->outtask,
+ &state->driver.select->outiotask.task,
state->type);
if (mode == ERL_DRV_WRITE)
break;
case ERL_DRV_READ:
ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL);
abort_task(state->driver.select->inport,
- &state->driver.select->intask,
+ &state->driver.select->iniotask.task,
state->type);
break;
default:
@@ -440,16 +522,14 @@ deselect(ErtsDrvEventState *state, int mode)
if (!(state->events)) {
switch (state->type) {
case ERTS_EV_TYPE_DRV_SEL:
- ASSERT(!erts_port_task_is_scheduled(&state->driver.select->intask));
- ASSERT(!erts_port_task_is_scheduled(&state->driver.select->outtask));
- erts_free(ERTS_ALC_T_DRV_SEL_D_STATE,
- state->driver.select);
+ state->driver.select->inport = NIL;
+ state->driver.select->outport = NIL;
break;
#if ERTS_CIO_HAVE_DRV_EVENT
case ERTS_EV_TYPE_DRV_EV:
- ASSERT(!erts_port_task_is_scheduled(&state->driver.event->task));
- erts_free(ERTS_ALC_T_DRV_EV_D_STATE,
- state->driver.event);
+ state->driver.event->port = NIL;
+ state->driver.event->data = NULL;
+ state->driver.event->removed_events = (ErtsPollEvents) 0;
break;
#endif
case ERTS_EV_TYPE_NONE:
@@ -459,20 +539,297 @@ deselect(ErtsDrvEventState *state, int mode)
break;
}
- state->driver.select = NULL;
state->type = ERTS_EV_TYPE_NONE;
- state->flags = 0;
+ state->flags &= ~ERTS_EV_FLAG_USED;
remember_removed(state, &pollset);
}
}
-
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
# define IS_FD_UNKNOWN(state) ((state)->type == ERTS_EV_TYPE_NONE && (state)->remove_cnt == 0)
#else
# define IS_FD_UNKNOWN(state) ((state) == NULL)
#endif
+static ERTS_INLINE void
+check_fd_cleanup(ErtsDrvEventState *state,
+#if ERTS_CIO_HAVE_DRV_EVENT
+ ErtsDrvEventDataState **free_event,
+#endif
+ ErtsDrvSelectDataState **free_select)
+{
+ erts_aint_t current_cio_time;
+
+ ERTS_SMP_LC_ASSERT(erts_smp_lc_mtx_is_locked(fd_mtx(state->fd)));
+
+ current_cio_time = erts_smp_atomic_read_acqb(&erts_check_io_time);
+ *free_select = NULL;
+ if (state->driver.select
+ && (state->type != ERTS_EV_TYPE_DRV_SEL)
+ && !is_iotask_active(&state->driver.select->iniotask, current_cio_time)
+ && !is_iotask_active(&state->driver.select->outiotask, current_cio_time)) {
+
+ *free_select = state->driver.select;
+ state->driver.select = NULL;
+ }
+
+#if ERTS_CIO_HAVE_DRV_EVENT
+ *free_event = NULL;
+ if (state->driver.event
+ && (state->type != ERTS_EV_TYPE_DRV_EV)
+ && !is_iotask_active(&state->driver.event->iotask, current_cio_time)) {
+
+ *free_event = state->driver.event;
+ state->driver.event = NULL;
+ }
+#endif
+
+#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
+ if (((state->type != ERTS_EV_TYPE_NONE)
+ | state->remove_cnt
+#if ERTS_CIO_HAVE_DRV_EVENT
+ | (state->driver.event != NULL)
+#endif
+ | (state->driver.select != NULL)) == 0) {
+
+ hash_erase_drv_ev_state(state);
+
+ }
+#endif
+}
+
+static ERTS_INLINE int
+check_cleanup_active_fd(ErtsSysFdType fd,
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ ErtsPollControlEntry *pce,
+ int *pce_ix,
+#endif
+ erts_aint_t current_cio_time)
+{
+ ErtsDrvEventState *state;
+ int active = 0;
+ erts_smp_mtx_t *mtx = fd_mtx(fd);
+ void *free_select = NULL;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ void *free_event = NULL;
+#endif
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ ErtsPollEvents evon = 0, evoff = 0;
+#endif
+
+ erts_smp_mtx_lock(mtx);
+
+#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
+ state = &drv_ev_state[(int) fd];
+#else
+ state = hash_get_drv_ev_state(fd); /* may be NULL! */
+ if (state)
+#endif
+ {
+ if (state->driver.select) {
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ if (is_iotask_active(&state->driver.select->iniotask, current_cio_time)) {
+ active = 1;
+ if ((state->events & ERTS_POLL_EV_IN)
+ && !(state->flags & ERTS_EV_FLAG_DEFER_IN_EV)) {
+ evoff |= ERTS_POLL_EV_IN;
+ state->flags |= ERTS_EV_FLAG_DEFER_IN_EV;
+ }
+ }
+ else if (state->flags & ERTS_EV_FLAG_DEFER_IN_EV) {
+ if (state->events & ERTS_POLL_EV_IN)
+ evon |= ERTS_POLL_EV_IN;
+ state->flags &= ~ERTS_EV_FLAG_DEFER_IN_EV;
+ }
+ if (is_iotask_active(&state->driver.select->outiotask, current_cio_time)) {
+ active = 1;
+ if ((state->events & ERTS_POLL_EV_OUT)
+ && !(state->flags & ERTS_EV_FLAG_DEFER_OUT_EV)) {
+ evoff |= ERTS_POLL_EV_OUT;
+ state->flags |= ERTS_EV_FLAG_DEFER_OUT_EV;
+ }
+ }
+ else if (state->flags & ERTS_EV_FLAG_DEFER_OUT_EV) {
+ if (state->events & ERTS_POLL_EV_OUT)
+ evon |= ERTS_POLL_EV_OUT;
+ state->flags &= ~ERTS_EV_FLAG_DEFER_OUT_EV;
+ }
+ if (active)
+ (void) 0;
+ else
+#else
+ if (is_iotask_active(&state->driver.select->iniotask, current_cio_time)
+ || is_iotask_active(&state->driver.select->outiotask, current_cio_time))
+ active = 1;
+ else
+#endif
+ if (state->type != ERTS_EV_TYPE_DRV_SEL) {
+ free_select = state->driver.select;
+ state->driver.select = NULL;
+ }
+ }
+
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (state->driver.event) {
+ if (is_iotask_active(&state->driver.event->iotask, current_cio_time)) {
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ ErtsPollEvents evs = state->events & ~state->driver.event->deferred_events;
+ if (evs) {
+ evoff |= evs;
+ state->driver.event->deferred_events |= evs;
+ }
+#endif
+ active = 1;
+ }
+ else if (state->type != ERTS_EV_TYPE_DRV_EV) {
+ free_event = state->driver.event;
+ state->driver.event = NULL;
+ }
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ else {
+ ErtsPollEvents evs = state->events & state->driver.event->deferred_events;
+ if (evs) {
+ evon |= evs;
+ state->driver.event->deferred_events = 0;
+ }
+ }
+#endif
+
+ }
+#endif
+
+#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
+ if (((state->type != ERTS_EV_TYPE_NONE) | state->remove_cnt | active) == 0)
+ hash_erase_drv_ev_state(state);
+#endif
+
+ }
+
+ erts_smp_mtx_unlock(mtx);
+
+ if (free_select)
+ free_drv_select_data(free_select);
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (free_event)
+ free_drv_event_data(free_event);
+#endif
+
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ if (evoff) {
+ ErtsPollControlEntry *pcep = &pce[(*pce_ix)++];
+ pcep->fd = fd;
+ pcep->events = evoff;
+ pcep->on = 0;
+ }
+ if (evon) {
+ ErtsPollControlEntry *pcep = &pce[(*pce_ix)++];
+ pcep->fd = fd;
+ pcep->events = evon;
+ pcep->on = 1;
+ }
+#endif
+
+ return active;
+}
+
+static void
+check_cleanup_active_fds(erts_aint_t current_cio_time)
+{
+ int six = pollset.active_fd.six;
+ int eix = pollset.active_fd.eix;
+ erts_aint32_t no = erts_smp_atomic32_read_dirty(&pollset.active_fd.no);
+ int size = pollset.active_fd.size;
+ int ix = six;
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ /* every fd might add two entries */
+ Uint pce_sz = 2*sizeof(ErtsPollControlEntry)*no;
+ ErtsPollControlEntry *pctrl_entries = (pce_sz
+ ? erts_alloc(ERTS_ALC_T_TMP, pce_sz)
+ : NULL);
+ int pctrl_ix = 0;
+#endif
+
+ while (ix != eix) {
+ ErtsSysFdType fd = pollset.active_fd.array[ix];
+ int nix = ix + 1;
+ if (nix >= size)
+ nix = 0;
+ ASSERT(fd != ERTS_SYS_FD_INVALID);
+ if (!check_cleanup_active_fd(fd,
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ pctrl_entries,
+ &pctrl_ix,
+#endif
+ current_cio_time)) {
+ no--;
+ if (ix == six) {
+#ifdef DEBUG
+ pollset.active_fd.array[ix] = ERTS_SYS_FD_INVALID;
+#endif
+ six = nix;
+ }
+ else {
+ pollset.active_fd.array[ix] = pollset.active_fd.array[six];
+#ifdef DEBUG
+ pollset.active_fd.array[six] = ERTS_SYS_FD_INVALID;
+#endif
+ six++;
+ if (six >= size)
+ six = 0;
+ }
+ }
+ ix = nix;
+ }
+
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ ASSERT(pctrl_ix <= pce_sz/sizeof(ErtsPollControlEntry));
+ if (pctrl_ix)
+ ERTS_CIO_POLL_CTLV(pollset.ps, pctrl_entries, pctrl_ix);
+ if (pctrl_entries)
+ erts_free(ERTS_ALC_T_TMP, pctrl_entries);
+#endif
+
+ pollset.active_fd.six = six;
+ pollset.active_fd.eix = eix;
+ erts_smp_atomic32_set_relb(&pollset.active_fd.no, no);
+}
+
+static ERTS_INLINE void
+add_active_fd(ErtsSysFdType fd)
+{
+ int eix = pollset.active_fd.eix;
+ int size = pollset.active_fd.size;
+
+
+ pollset.active_fd.array[eix] = fd;
+
+ erts_smp_atomic32_set_relb(&pollset.active_fd.no,
+ (erts_smp_atomic32_read_dirty(&pollset.active_fd.no)
+ + 1));
+
+ eix++;
+ if (eix >= size)
+ eix = 0;
+ if (pollset.active_fd.six == eix) {
+ pollset.active_fd.six = 0;
+ eix = size;
+ size += ERTS_ACTIVE_FD_INC;
+ pollset.active_fd.array = erts_realloc(ERTS_ALC_T_ACTIVE_FD_ARR,
+ pollset.active_fd.array,
+ sizeof(ErtsSysFdType)*size);
+ pollset.active_fd.size = size;
+#ifdef DEBUG
+ {
+ int i;
+ for (i = eix + 1; i < size; i++)
+ pollset.active_fd.array[i] = ERTS_SYS_FD_INVALID;
+ }
+#endif
+
+ }
+
+ pollset.active_fd.eix = eix;
+}
int
ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
@@ -489,6 +846,10 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
ErtsDrvEventState *state;
int wake_poller;
int ret;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ ErtsDrvEventDataState *free_event = NULL;
+#endif
+ ErtsDrvSelectDataState *free_select = NULL;
#ifdef USE_VM_PROBES
DTRACE_CHARBUF(name, 64);
#endif
@@ -589,9 +950,9 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
if (new_events & (ERTS_POLL_EV_ERR|ERTS_POLL_EV_NVAL)) {
if (state->type == ERTS_EV_TYPE_DRV_SEL && !state->events) {
state->type = ERTS_EV_TYPE_NONE;
- state->flags = 0;
- erts_free(ERTS_ALC_T_DRV_SEL_D_STATE, state->driver.select);
- state->driver.select = NULL;
+ state->flags &= ~ERTS_EV_FLAG_USED;
+ state->driver.select->inport = NIL;
+ state->driver.select->outport = NIL;
}
ret = -1;
goto done;
@@ -609,18 +970,10 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
state->events = new_events;
if (ctl_events) {
if (on) {
- if (state->type == ERTS_EV_TYPE_NONE) {
- ErtsDrvSelectDataState *dsdsp
- = erts_alloc(ERTS_ALC_T_DRV_SEL_D_STATE,
- sizeof(ErtsDrvSelectDataState));
- dsdsp->inport = NIL;
- dsdsp->outport = NIL;
- erts_port_task_handle_init(&dsdsp->intask);
- erts_port_task_handle_init(&dsdsp->outtask);
- ASSERT(state->driver.select == NULL);
- state->driver.select = dsdsp;
+ if (!state->driver.select)
+ state->driver.select = alloc_drv_select_data();
+ if (state->type == ERTS_EV_TYPE_NONE)
state->type = ERTS_EV_TYPE_DRV_SEL;
- }
ASSERT(state->type == ERTS_EV_TYPE_DRV_SEL);
if (ctl_events & ERTS_POLL_EV_IN)
state->driver.select->inport = id;
@@ -641,17 +994,12 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
state->driver.select->outport = NIL;
}
if (new_events == 0) {
- ASSERT(!erts_port_task_is_scheduled(&state->driver.select->intask));
- ASSERT(!erts_port_task_is_scheduled(&state->driver.select->outtask));
if (old_events != 0) {
remember_removed(state, &pollset);
}
if ((mode & ERL_DRV_USE) || !(state->flags & ERTS_EV_FLAG_USED)) {
state->type = ERTS_EV_TYPE_NONE;
- state->flags = 0;
- erts_free(ERTS_ALC_T_DRV_SEL_D_STATE,
- state->driver.select);
- state->driver.select = NULL;
+ state->flags &= ~ERTS_EV_FLAG_USED;
}
/*else keep it, as fd will probably be selected upon again */
}
@@ -682,13 +1030,15 @@ ERTS_CIO_EXPORT(driver_select)(ErlDrvPort ix,
ret = 0;
-done:;
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
- if (state->type == ERTS_EV_TYPE_NONE && state->remove_cnt == 0) {
- hash_erase_drv_ev_state(state);
- }
+done:
+
+ check_fd_cleanup(state,
+#if ERTS_CIO_HAVE_DRV_EVENT
+ &free_event,
#endif
-done_unknown:
+ &free_select);
+
+done_unknown:
erts_smp_mtx_unlock(fd_mtx(fd));
if (stop_select_fn) {
int was_unmasked = erts_block_fpe();
@@ -696,6 +1046,12 @@ done_unknown:
(*stop_select_fn)(e, NULL);
erts_unblock_fpe(was_unmasked);
}
+ if (free_select)
+ free_drv_select_data(free_select);
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (free_event)
+ free_drv_event_data(free_event);
+#endif
return ret;
}
@@ -715,6 +1071,10 @@ ERTS_CIO_EXPORT(driver_event)(ErlDrvPort ix,
ErtsDrvEventState *state;
int do_wake = 0;
int ret;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ ErtsDrvEventDataState *free_event;
+#endif
+ ErtsDrvSelectDataState *free_select;
Port *prt = erts_drvport2port(ix);
if (prt == ERTS_INVALID_ERL_DRV_PORT)
@@ -795,10 +1155,8 @@ ERTS_CIO_EXPORT(driver_event)(ErlDrvPort ix,
state->driver.event->removed_events |= remove_events;
}
else {
- state->driver.event
- = erts_alloc(ERTS_ALC_T_DRV_EV_D_STATE,
- sizeof(ErtsDrvEventDataState));
- erts_port_task_handle_init(&state->driver.event->task);
+ if (!state->driver.event)
+ state->driver.event = alloc_drv_event_data();
state->driver.event->port = id;
state->driver.event->removed_events = (ErtsPollEvents) 0;
state->type = ERTS_EV_TYPE_DRV_EV;
@@ -808,10 +1166,10 @@ ERTS_CIO_EXPORT(driver_event)(ErlDrvPort ix,
else {
if (state->type == ERTS_EV_TYPE_DRV_EV) {
abort_tasks(state, 0);
- erts_free(ERTS_ALC_T_DRV_EV_D_STATE,
- state->driver.event);
+ state->driver.event->port = NIL;
+ state->driver.event->data = NULL;
+ state->driver.event->removed_events = (ErtsPollEvents) 0;
}
- state->driver.select = NULL;
state->type = ERTS_EV_TYPE_NONE;
remember_removed(state, &pollset);
}
@@ -821,12 +1179,22 @@ ERTS_CIO_EXPORT(driver_event)(ErlDrvPort ix,
ret = 0;
done:
-#ifndef ERTS_SYS_CONTINOUS_FD_NUMBERS
- if (state->type == ERTS_EV_TYPE_NONE && state->remove_cnt == 0) {
- hash_erase_drv_ev_state(state);
- }
+
+ check_fd_cleanup(state,
+#if ERTS_CIO_HAVE_DRV_EVENT
+ &free_event,
#endif
+ &free_select);
+
erts_smp_mtx_unlock(fd_mtx(fd));
+
+ if (free_select)
+ free_drv_select_data(free_select);
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (free_event)
+ free_drv_event_data(free_event);
+#endif
+
return ret;
#endif
}
@@ -1019,7 +1387,7 @@ steal_pending_stop_select(erts_dsprintf_buf_t *dsbufp, ErlDrvPort ix,
* In either case stop_select should not be called.
*/
state->type = ERTS_EV_TYPE_NONE;
- state->flags = 0;
+ state->flags &= ~ERTS_EV_FLAG_USED;
if (state->driver.drv_ptr->handle) {
erts_ddll_dereference_driver(state->driver.drv_ptr->handle);
}
@@ -1091,38 +1459,103 @@ event_large_fd_error(ErlDrvPort ix, ErtsSysFdType fd, ErlDrvEventData event_data
#endif
#endif
+static ERTS_INLINE int
+io_task_schedule_allowed(ErtsDrvEventState *state,
+ ErtsPortTaskType type,
+ erts_aint_t current_cio_time)
+{
+ ErtsIoTask *io_task;
+
+ switch (type) {
+ case ERTS_PORT_TASK_INPUT:
+ if (!state->driver.select)
+ return 0;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (state->driver.event)
+ return 0;
+#endif
+ io_task = &state->driver.select->iniotask;
+ break;
+ case ERTS_PORT_TASK_OUTPUT:
+ if (!state->driver.select)
+ return 0;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (state->driver.event)
+ return 0;
+#endif
+ io_task = &state->driver.select->outiotask;
+ break;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ case ERTS_PORT_TASK_EVENT:
+ if (!state->driver.event)
+ return 0;
+ if (state->driver.select)
+ return 0;
+ io_task = &state->driver.event->iotask;
+ break;
+#endif
+ default:
+ ERTS_INTERNAL_ERROR("Invalid I/O-task type");
+ return 0;
+ }
+
+ return !is_iotask_active(io_task, current_cio_time);
+}
+
static ERTS_INLINE void
-iready(Eterm id, ErtsDrvEventState *state)
+iready(Eterm id, ErtsDrvEventState *state, erts_aint_t current_cio_time)
{
- if (erts_port_task_schedule(id,
- &state->driver.select->intask,
- ERTS_PORT_TASK_INPUT,
- (ErlDrvEvent) state->fd) != 0) {
- stale_drv_select(id, state, ERL_DRV_READ);
+ if (io_task_schedule_allowed(state,
+ ERTS_PORT_TASK_INPUT,
+ current_cio_time)) {
+ ErtsIoTask *iotask = &state->driver.select->iniotask;
+ erts_smp_atomic_set_nob(&iotask->executed_time, current_cio_time);
+ if (erts_port_task_schedule(id,
+ &iotask->task,
+ ERTS_PORT_TASK_INPUT,
+ (ErlDrvEvent) state->fd) != 0) {
+ stale_drv_select(id, state, ERL_DRV_READ);
+ }
+ add_active_fd(state->fd);
}
}
static ERTS_INLINE void
-oready(Eterm id, ErtsDrvEventState *state)
+oready(Eterm id, ErtsDrvEventState *state, erts_aint_t current_cio_time)
{
- if (erts_port_task_schedule(id,
- &state->driver.select->outtask,
- ERTS_PORT_TASK_OUTPUT,
- (ErlDrvEvent) state->fd) != 0) {
- stale_drv_select(id, state, ERL_DRV_WRITE);
+ if (io_task_schedule_allowed(state,
+ ERTS_PORT_TASK_OUTPUT,
+ current_cio_time)) {
+ ErtsIoTask *iotask = &state->driver.select->outiotask;
+ erts_smp_atomic_set_nob(&iotask->executed_time, current_cio_time);
+ if (erts_port_task_schedule(id,
+ &iotask->task,
+ ERTS_PORT_TASK_OUTPUT,
+ (ErlDrvEvent) state->fd) != 0) {
+ stale_drv_select(id, state, ERL_DRV_WRITE);
+ }
+ add_active_fd(state->fd);
}
}
#if ERTS_CIO_HAVE_DRV_EVENT
static ERTS_INLINE void
-eready(Eterm id, ErtsDrvEventState *state, ErlDrvEventData event_data)
+eready(Eterm id, ErtsDrvEventState *state, ErlDrvEventData event_data,
+ erts_aint_t current_cio_time)
{
- if (erts_port_task_schedule(id,
- &state->driver.event->task,
- ERTS_PORT_TASK_EVENT,
- (ErlDrvEvent) state->fd,
- event_data) != 0) {
- stale_drv_select(id, state, 0);
+ if (io_task_schedule_allowed(state,
+ ERTS_PORT_TASK_EVENT,
+ current_cio_time)) {
+ ErtsIoTask *iotask = &state->driver.event->iotask;
+ erts_smp_atomic_set_nob(&iotask->executed_time, current_cio_time);
+ if (erts_port_task_schedule(id,
+ &iotask->task,
+ ERTS_PORT_TASK_EVENT,
+ (ErlDrvEvent) state->fd,
+ event_data) != 0) {
+ stale_drv_select(id, state, 0);
+ }
+ add_active_fd(state->fd);
}
}
#endif
@@ -1153,10 +1586,11 @@ ERTS_CIO_EXPORT(erts_check_io_interrupt_timed)(int set,
void
ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
{
- ErtsPollResFd pollres[256];
+ ErtsPollResFd *pollres;
int pollres_len;
SysTimeval wait_time;
int poll_ret, i;
+ erts_aint_t current_cio_time;
restart:
@@ -1173,10 +1607,24 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
wait_time.tv_usec = 0;
}
+ /*
+ * No need for an atomic inc op when incrementing
+ * erts_check_io_time, since only one thread can
+ * check io at a time.
+ */
+ current_cio_time = erts_smp_atomic_read_dirty(&erts_check_io_time);
+ current_cio_time++;
+ erts_smp_atomic_set_relb(&erts_check_io_time, current_cio_time);
+
+ check_cleanup_active_fds(current_cio_time);
+
#ifdef ERTS_ENABLE_LOCK_CHECK
erts_lc_check_exact(NULL, 0); /* No locks should be locked */
#endif
- pollres_len = sizeof(pollres)/sizeof(ErtsPollResFd);
+
+ pollres_len = erts_smp_atomic32_read_dirty(&pollset.active_fd.no) + ERTS_CHECK_IO_POLL_RES_LEN;
+
+ pollres = erts_alloc(ERTS_ALC_T_TMP, sizeof(ErtsPollResFd)*pollres_len);
erts_smp_atomic_set_nob(&pollset.in_poll_wait, 1);
@@ -1196,6 +1644,7 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
if (poll_ret != 0) {
erts_smp_atomic_set_nob(&pollset.in_poll_wait, 0);
forget_removed(&pollset);
+ erts_free(ERTS_ALC_T_TMP, pollres);
if (poll_ret == EAGAIN) {
goto restart;
}
@@ -1255,15 +1704,15 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
if ((revents & ERTS_POLL_EV_IN)
|| (!(revents & ERTS_POLL_EV_OUT)
&& state->events & ERTS_POLL_EV_IN)) {
- iready(state->driver.select->inport, state);
+ iready(state->driver.select->inport, state, current_cio_time);
}
else if (state->events & ERTS_POLL_EV_OUT) {
- oready(state->driver.select->outport, state);
+ oready(state->driver.select->outport, state, current_cio_time);
}
}
else if (revents & (ERTS_POLL_EV_IN|ERTS_POLL_EV_OUT)) {
if (revents & ERTS_POLL_EV_OUT) {
- oready(state->driver.select->outport, state);
+ oready(state->driver.select->outport, state, current_cio_time);
}
/* Someone might have deselected input since revents
was read (true also on the non-smp emulator since
@@ -1271,7 +1720,7 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
revents... */
revents &= ~(~state->events & ERTS_POLL_EV_IN);
if (revents & ERTS_POLL_EV_IN) {
- iready(state->driver.select->inport, state);
+ iready(state->driver.select->inport, state, current_cio_time);
}
}
else if (revents & ERTS_POLL_EV_NVAL) {
@@ -1279,6 +1728,7 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
state->driver.select->inport,
state->driver.select->outport,
state->events);
+ add_active_fd(state->fd);
}
break;
}
@@ -1296,8 +1746,7 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
if (revents) {
event_data->events = state->events;
event_data->revents = revents;
-
- eready(state->driver.event->port, state, event_data);
+ eready(state->driver.event->port, state, event_data, current_cio_time);
}
break;
}
@@ -1315,6 +1764,7 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
(int) state->type);
ASSERT(0);
deselect(state, 0);
+ add_active_fd(state->fd);
break;
}
}
@@ -1326,6 +1776,7 @@ ERTS_CIO_EXPORT(erts_check_io)(int do_wait)
}
erts_smp_atomic_set_nob(&pollset.in_poll_wait, 0);
+ erts_free(ERTS_ALC_T_TMP, pollres);
forget_removed(&pollset);
}
@@ -1440,10 +1891,27 @@ static void drv_ev_state_free(void *des)
void
ERTS_CIO_EXPORT(erts_init_check_io)(void)
{
+ erts_smp_atomic_init_nob(&erts_check_io_time, 0);
erts_smp_atomic_init_nob(&pollset.in_poll_wait, 0);
+
ERTS_CIO_POLL_INIT();
pollset.ps = ERTS_CIO_NEW_POLLSET();
+ pollset.active_fd.six = 0;
+ pollset.active_fd.eix = 0;
+ erts_smp_atomic32_init_nob(&pollset.active_fd.no, 0);
+ pollset.active_fd.size = ERTS_ACTIVE_FD_INC;
+ pollset.active_fd.array = erts_alloc(ERTS_ALC_T_ACTIVE_FD_ARR,
+ sizeof(ErtsSysFdType)*ERTS_ACTIVE_FD_INC);
+#ifdef DEBUG
+ {
+ int i;
+ for (i = 0; i < ERTS_ACTIVE_FD_INC; i++)
+ pollset.active_fd.array[i] = ERTS_SYS_FD_INVALID;
+ }
+#endif
+
+
#ifdef ERTS_SMP
init_removed_fd_alloc();
pollset.removed_list = NULL;
@@ -1519,12 +1987,27 @@ Eterm
ERTS_CIO_EXPORT(erts_check_io_info)(void *proc)
{
Process *p = (Process *) proc;
- Eterm tags[15], values[15], res;
+ Eterm tags[16], values[16], res;
Uint sz, *szp, *hp, **hpp, memory_size;
Sint i;
ErtsPollInfo pi;
-
- ERTS_CIO_POLL_INFO(pollset.ps, &pi);
+ erts_aint_t cio_time = erts_smp_atomic_read_acqb(&erts_check_io_time);
+ int active_fds = (int) erts_smp_atomic32_read_acqb(&pollset.active_fd.no);
+
+ while (1) {
+ erts_aint_t post_cio_time;
+ int post_active_fds;
+
+ ERTS_CIO_POLL_INFO(pollset.ps, &pi);
+
+ post_cio_time = erts_smp_atomic_read_mb(&erts_check_io_time);
+ post_active_fds = (int) erts_smp_atomic32_read_acqb(&pollset.active_fd.no);
+ if (cio_time == post_cio_time && active_fds == post_active_fds)
+ break;
+ cio_time = post_cio_time;
+ active_fds = post_active_fds;
+ }
+
memory_size = pi.memory_size;
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
memory_size += sizeof(ErtsDrvEventState) * erts_smp_atomic_read_nob(&drv_ev_state_len);
@@ -1588,6 +2071,9 @@ ERTS_CIO_EXPORT(erts_check_io_info)(void *proc)
tags[i] = erts_bld_atom(hpp, szp, "max_fds");
values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.max_fds);
+ tags[i] = erts_bld_atom(hpp, szp, "active_fds");
+ values[i++] = erts_bld_uint(hpp, szp, (Uint) active_fds);
+
#ifdef ERTS_POLL_COUNT_AVOIDED_WAKEUPS
tags[i] = erts_bld_atom(hpp, szp, "no_avoided_wakeups");
values[i++] = erts_bld_uint(hpp, szp, (Uint) pi.no_avoided_wakeups);
@@ -1642,6 +2128,8 @@ print_events(ErtsPollEvents ev)
typedef struct {
int used_fds;
int num_errors;
+ int no_driver_select_structs;
+ int no_driver_event_structs;
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
int internal_fds;
ErtsPollEvents *epep;
@@ -1664,6 +2152,13 @@ static void doit_erts_check_io_debug(void *vstate, void *vcounters)
struct stat stat_buf;
#endif
+ if (state->driver.select)
+ counters->no_driver_select_structs++;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ if (state->driver.event)
+ counters->no_driver_event_structs++;
+#endif
+
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
if (state->events || ep_events) {
if (ep_events & ERTS_POLL_EV_NVAL) {
@@ -1802,6 +2297,7 @@ static void doit_erts_check_io_debug(void *vstate, void *vcounters)
}
}
}
+#if ERTS_CIO_HAVE_DRV_EVENT
else if (state->type == ERTS_EV_TYPE_DRV_EV) {
Eterm id;
erts_printf("driver_event ");
@@ -1837,6 +2333,7 @@ static void doit_erts_check_io_debug(void *vstate, void *vcounters)
erts_free_port_names(pnp);
}
}
+#endif
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
else if (internal) {
erts_printf("internal ");
@@ -1876,7 +2373,7 @@ static void doit_erts_check_io_debug(void *vstate, void *vcounters)
}
int
-ERTS_CIO_EXPORT(erts_check_io_debug)(void)
+ERTS_CIO_EXPORT(erts_check_io_debug)(ErtsCheckIoDebugInfo *ciodip)
{
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
int fd, len;
@@ -1885,6 +2382,10 @@ ERTS_CIO_EXPORT(erts_check_io_debug)(void)
ErtsDrvEventState null_des;
null_des.driver.select = NULL;
+#if ERTS_CIO_HAVE_DRV_EVENT
+ null_des.driver.event = NULL;
+#endif
+ null_des.driver.drv_ptr = NULL;
null_des.events = 0;
null_des.remove_cnt = 0;
null_des.type = ERTS_EV_TYPE_NONE;
@@ -1904,6 +2405,8 @@ ERTS_CIO_EXPORT(erts_check_io_debug)(void)
#endif
counters.used_fds = 0;
counters.num_errors = 0;
+ counters.no_driver_select_structs = 0;
+ counters.no_driver_event_structs = 0;
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
len = erts_smp_atomic_read_nob(&drv_ev_state_len);
@@ -1920,8 +2423,16 @@ ERTS_CIO_EXPORT(erts_check_io_debug)(void)
erts_smp_thr_progress_unblock();
+ ciodip->no_used_fds = counters.used_fds;
+ ciodip->no_driver_select_structs = counters.no_driver_select_structs;
+ ciodip->no_driver_event_structs = counters.no_driver_event_structs;
+
erts_printf("\n");
erts_printf("used fds=%d\n", counters.used_fds);
+ erts_printf("Number of driver_select() structures=%d\n", counters.no_driver_select_structs);
+#if ERTS_CIO_HAVE_DRV_EVENT
+ erts_printf("Number of driver_event() structures=%d\n", counters.no_driver_event_structs);
+#endif
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
erts_printf("internal fds=%d\n", counters.internal_fds);
#endif
@@ -1930,6 +2441,7 @@ ERTS_CIO_EXPORT(erts_check_io_debug)(void)
#ifdef ERTS_SYS_CONTINOUS_FD_NUMBERS
erts_free(ERTS_ALC_T_TMP, (void *) counters.epep);
#endif
+
return counters.num_errors;
}
diff --git a/erts/emulator/sys/common/erl_check_io.h b/erts/emulator/sys/common/erl_check_io.h
index edab7947ba..d01297d55c 100644
--- a/erts/emulator/sys/common/erl_check_io.h
+++ b/erts/emulator/sys/common/erl_check_io.h
@@ -26,6 +26,7 @@
#ifndef ERL_CHECK_IO_H__
#define ERL_CHECK_IO_H__
+#include "sys.h"
#include "erl_sys_driver.h"
#ifdef ERTS_ENABLE_KERNEL_POLL
@@ -52,8 +53,8 @@ void erts_check_io_kp(int);
void erts_check_io_nkp(int);
void erts_init_check_io_kp(void);
void erts_init_check_io_nkp(void);
-int erts_check_io_debug_kp(void);
-int erts_check_io_debug_nkp(void);
+int erts_check_io_debug_kp(ErtsCheckIoDebugInfo *);
+int erts_check_io_debug_nkp(ErtsCheckIoDebugInfo *);
#else /* !ERTS_ENABLE_KERNEL_POLL */
@@ -70,6 +71,27 @@ void erts_init_check_io(void);
#endif
+extern erts_smp_atomic_t erts_check_io_time;
+
+typedef struct {
+ ErtsPortTaskHandle task;
+ erts_smp_atomic_t executed_time;
+} ErtsIoTask;
+
+ERTS_GLB_INLINE void erts_io_notify_port_task_executed(ErtsPortTaskHandle *pthp);
+
+#if ERTS_GLB_INLINE_INCL_FUNC_DEF
+
+ERTS_GLB_INLINE void
+erts_io_notify_port_task_executed(ErtsPortTaskHandle *pthp)
+{
+ ErtsIoTask *itp = (ErtsIoTask *) (((char *) pthp) - offsetof(ErtsIoTask, task));
+ erts_aint_t ci_time = erts_smp_atomic_read_acqb(&erts_check_io_time);
+ erts_smp_atomic_set_relb(&itp->executed_time, ci_time);
+}
+
+#endif
+
#endif /* ERL_CHECK_IO_H__ */
#if !defined(ERL_CHECK_IO_C__) && !defined(ERTS_ALLOC_C__)
@@ -81,6 +103,16 @@ void erts_init_check_io(void);
#include "erl_poll.h"
#include "erl_port_task.h"
+#ifdef __WIN32__
+/*
+ * Current erts_poll implementation for Windows cannot handle
+ * active events in the set of events polled.
+ */
+# define ERTS_CIO_DEFER_ACTIVE_EVENTS 1
+#else
+# define ERTS_CIO_DEFER_ACTIVE_EVENTS 0
+#endif
+
/*
* ErtsDrvEventDataState is used by driver_event() which is almost never
* used. We allocate ErtsDrvEventDataState separate since we dont wan't
@@ -91,13 +123,16 @@ typedef struct {
Eterm port;
ErlDrvEventData data;
ErtsPollEvents removed_events;
- ErtsPortTaskHandle task;
+#if ERTS_CIO_DEFER_ACTIVE_EVENTS
+ ErtsPollEvents deferred_events;
+#endif
+ ErtsIoTask iotask;
} ErtsDrvEventDataState;
typedef struct {
Eterm inport;
Eterm outport;
- ErtsPortTaskHandle intask;
- ErtsPortTaskHandle outtask;
+ ErtsIoTask iniotask;
+ ErtsIoTask outiotask;
} ErtsDrvSelectDataState;
#endif /* #ifndef ERL_CHECK_IO_INTERNAL__ */
diff --git a/erts/emulator/sys/common/erl_sys_common_misc.c b/erts/emulator/sys/common/erl_sys_common_misc.c
index 31ad3b82d5..c5e804a62d 100644
--- a/erts/emulator/sys/common/erl_sys_common_misc.c
+++ b/erts/emulator/sys/common/erl_sys_common_misc.c
@@ -44,6 +44,14 @@
#endif
#endif
+/*
+ * erts_check_io_time is used by the erl_check_io implementation. The
+ * global erts_check_io_time variable is declared here since there
+ * (often) exist two versions of erl_check_io (kernel-poll and
+ * non-kernel-poll), and we dont want two versions of this variable.
+ */
+erts_smp_atomic_t erts_check_io_time;
+
/* Written once and only once */
static int filename_encoding = ERL_FILENAME_UNKNOWN;