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authorRickard Green <rickard@erlang.org>2013-02-08 14:39:31 +0100
committerRickard Green <rickard@erlang.org>2013-02-13 12:23:30 +0100
commit953a4bd91e471126370bf5a70956ad233fda189a (patch)
treea51a87e005d63821330efdd8db5374f63fe886d2
parent56b2a90c7c0e1d9c1e964ee324413d651a37e6e3 (diff)
downloadotp-953a4bd91e471126370bf5a70956ad233fda189a.tar.gz
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Implement erl_drv_consume_timeslice()
-rw-r--r--erts/doc/src/erl_driver.xml58
-rw-r--r--erts/emulator/beam/bif.c17
-rw-r--r--erts/emulator/beam/bif.h7
-rw-r--r--erts/emulator/beam/erl_driver.h5
-rw-r--r--erts/emulator/beam/erl_port.h1
-rw-r--r--erts/emulator/beam/erl_port_task.c58
-rw-r--r--erts/emulator/beam/io.c22
-rw-r--r--erts/emulator/sys/win32/erl_win_dyn_driver.h4
-rw-r--r--erts/emulator/test/driver_SUITE.erl325
-rw-r--r--erts/emulator/test/driver_SUITE_data/Makefile.src3
-rw-r--r--erts/emulator/test/driver_SUITE_data/consume_timeslice_drv.c172
11 files changed, 643 insertions, 29 deletions
diff --git a/erts/doc/src/erl_driver.xml b/erts/doc/src/erl_driver.xml
index 1212c34586..bf392c76d7 100644
--- a/erts/doc/src/erl_driver.xml
+++ b/erts/doc/src/erl_driver.xml
@@ -170,10 +170,13 @@
callback, the best approach is to divide the work into multiple chunks of
work and trigger multiple calls to the
<seealso marker="driver_entry#timeout">timeout callback</seealso> using
- zero timeouts. This might, however, not always be possible, e.g. when
- calling third party libraries. In this case you typically want to dispatch
- the work to another thread. Information about thread primitives can be
- found below.</p>
+ zero timeouts. The
+ <seealso marker="#erl_drv_consume_timeslice"><c>erl_drv_consume_timeslice()</c></seealso>
+ function can be useful in order to determine when to trigger such
+ timeout callback calls. It might, however, not always be possible to
+ implement it this way, e.g. when calling third party libraries. In this
+ case you typically want to dispatch the work to another thread.
+ Information about thread primitives can be found below.</p>
</description>
<section>
@@ -2807,7 +2810,6 @@ ERL_DRV_EXT2TERM char *buf, ErlDrvUInt len
<p>This function is thread-safe.</p>
</desc>
</func>
-
<func>
<name><ret>int</ret><nametext>erl_drv_getenv(char *key, char *value, size_t *value_size)</nametext></name>
<fsummary>Get the value of an environment variable</fsummary>
@@ -2843,6 +2845,52 @@ ERL_DRV_EXT2TERM char *buf, ErlDrvUInt len
<p>This function is thread-safe.</p>
</desc>
</func>
+ <func>
+ <name><ret>int</ret><nametext>erl_drv_consume_timeslice(ErlDrvPort port, int percent)</nametext></name>
+ <fsummary>Give the runtime system a hint about how much CPU time the
+ current driver callback call has consumed</fsummary>
+ <desc>
+ <marker id="erl_drv_consume_timeslice"></marker>
+ <p>Arguments:</p>
+ <taglist>
+ <tag><c>port</c></tag>
+ <item>Port handle of the executing port.</item>
+ <tag><c>percent</c></tag>
+ <item>Approximate consumed fraction of a full
+ time-slice in percent.</item>
+ </taglist>
+ <p>Give the runtime system a hint about how much CPU time the
+ current driver callback call has consumed since last hint, or
+ since the start of the callback if no previous hint has been given.
+ The time is given as a fraction, in percent, of a full time-slice
+ that a port is allowed to execute before it should surrender the
+ CPU to other runnable ports or processes. Valid range is
+ <c>[1, 100]</c>. The scheduling time-slice is not an exact entity,
+ but can usually be approximated to about 1 millisecond.</p>
+
+ <p>Note that it is up to the runtime system to determine if and
+ how to use this information. Implementations on some platforms
+ may use other means in order to determine the consumed fraction
+ of the time-slice. Lengthy driver callbacks should regardless of
+ this frequently call the <c>erl_drv_consume_timeslice()</c>
+ function in order to determine if it is allowed to continue
+ execution or not.</p>
+
+ <p><c>erl_drv_consume_timeslice()</c> returns a non-zero value
+ if the time-slice has been exhausted, and zero if the callback is
+ allowed to continue execution. If a non-zero value is
+ returned the driver callback should return as soon as possible in
+ order for the port to be able to yield.</p>
+
+ <p>This function is provided to better support co-operative scheduling,
+ improve system responsiveness, and to make it easier to prevent
+ misbehaviors of the VM due to a port monopolizing a scheduler thread.
+ It can be used when dividing length work into a number of repeated
+ driver callback calls without the need to use threads. Also see the
+ important <seealso marker="#WARNING">warning</seealso> text at the
+ beginning of this document.</p>
+ </desc>
+ </func>
</funcs>
<section>
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index 46f76624a5..3c6cffb21e 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -2069,11 +2069,16 @@ BIF_RETTYPE send_3(BIF_ALIST_3)
result = do_send(p, to, msg, suspend, &ref);
if (result > 0) {
ERTS_VBUMP_REDS(p, result);
+ if (ERTS_IS_PROC_OUT_OF_REDS(p))
+ goto yield_return;
BIF_RET(am_ok);
}
switch (result) {
case 0:
+ /* May need to yield even though we do not bump reds here... */
+ if (ERTS_IS_PROC_OUT_OF_REDS(p))
+ goto yield_return;
BIF_RET(am_ok);
break;
case SEND_TRAP:
@@ -2091,10 +2096,10 @@ BIF_RETTYPE send_3(BIF_ALIST_3)
}
break;
case SEND_YIELD_RETURN:
- if (suspend)
- ERTS_BIF_YIELD_RETURN(p, am_ok);
- else
+ if (!suspend)
BIF_RET(am_nosuspend);
+ yield_return:
+ ERTS_BIF_YIELD_RETURN(p, am_ok);
case SEND_AWAIT_RESULT:
ASSERT(is_internal_ref(ref));
BIF_TRAP3(await_port_send_result_trap, p, ref, am_nosuspend, am_ok);
@@ -2133,11 +2138,16 @@ Eterm erl_send(Process *p, Eterm to, Eterm msg)
if (result > 0) {
ERTS_VBUMP_REDS(p, result);
+ if (ERTS_IS_PROC_OUT_OF_REDS(p))
+ goto yield_return;
BIF_RET(msg);
}
switch (result) {
case 0:
+ /* May need to yield even though we do not bump reds here... */
+ if (ERTS_IS_PROC_OUT_OF_REDS(p))
+ goto yield_return;
BIF_RET(msg);
break;
case SEND_TRAP:
@@ -2147,6 +2157,7 @@ Eterm erl_send(Process *p, Eterm to, Eterm msg)
ERTS_BIF_YIELD2(bif_export[BIF_send_2], p, to, msg);
break;
case SEND_YIELD_RETURN:
+ yield_return:
ERTS_BIF_YIELD_RETURN(p, msg);
case SEND_AWAIT_RESULT:
ASSERT(is_internal_ref(ref));
diff --git a/erts/emulator/beam/bif.h b/erts/emulator/beam/bif.h
index ceaf747875..51b77a95ed 100644
--- a/erts/emulator/beam/bif.h
+++ b/erts/emulator/beam/bif.h
@@ -35,6 +35,13 @@ extern Export* erts_format_cpu_topology_trap;
#define BIF_ARG_2 (BIF__ARGS[1])
#define BIF_ARG_3 (BIF__ARGS[2])
+#define ERTS_IS_PROC_OUT_OF_REDS(p) \
+ ((p)->fcalls > 0 \
+ ? 0 \
+ : (!ERTS_PROC_GET_SAVED_CALLS_BUF((p)) \
+ ? (p)->fcalls == 0 \
+ : ((p)->fcalls == -CONTEXT_REDS)))
+
#define BUMP_ALL_REDS(p) do { \
if (!ERTS_PROC_GET_SAVED_CALLS_BUF((p))) \
(p)->fcalls = 0; \
diff --git a/erts/emulator/beam/erl_driver.h b/erts/emulator/beam/erl_driver.h
index a9a50a10bf..e280563de1 100644
--- a/erts/emulator/beam/erl_driver.h
+++ b/erts/emulator/beam/erl_driver.h
@@ -408,6 +408,11 @@ EXTERN int driver_cancel_timer(ErlDrvPort port);
EXTERN int driver_read_timer(ErlDrvPort port, unsigned long *time_left);
/*
+ * Inform runtime system about lengthy work.
+ */
+EXTERN int erl_drv_consume_timeslice(ErlDrvPort port, int percent);
+
+/*
* Get plain-text error message from within a driver
*/
EXTERN char* erl_errno_id(int error);
diff --git a/erts/emulator/beam/erl_port.h b/erts/emulator/beam/erl_port.h
index a971685d7b..ac4f7af5a7 100644
--- a/erts/emulator/beam/erl_port.h
+++ b/erts/emulator/beam/erl_port.h
@@ -175,6 +175,7 @@ struct _erl_drv_port {
ErlDrvPDL port_data_lock;
ErtsPrtSD *psd; /* Port specific data */
+ int reds; /* Only used while executing driver callbacks */
};
#define ERTS_PORT_GET_CONNECTED(PRT) \
diff --git a/erts/emulator/beam/erl_port_task.c b/erts/emulator/beam/erl_port_task.c
index 9687db4780..ce045ec94e 100644
--- a/erts/emulator/beam/erl_port_task.c
+++ b/erts/emulator/beam/erl_port_task.c
@@ -1160,6 +1160,27 @@ select_task_for_exec(Port *pp,
}
/*
+ * Cut time slice
+ */
+
+int
+erl_drv_consume_timeslice(ErlDrvPort dprt, int percent)
+{
+ Port *pp = erts_drvport2port(dprt);
+ if (pp == ERTS_INVALID_ERL_DRV_PORT)
+ return -1;
+ if (percent < 1)
+ percent = 1;
+ else if (100 < percent)
+ percent = 100;
+ pp->reds += percent*((CONTEXT_REDS+99)/100);
+ if (pp->reds < CONTEXT_REDS)
+ return 0;
+ pp->reds = CONTEXT_REDS;
+ return 1;
+}
+
+/*
* Abort a scheduled task.
*/
@@ -1550,7 +1571,7 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
int processing_busy_q;
int res = 0;
int vreds = 0;
- int reds = ERTS_PORT_REDS_EXECUTE;
+ int reds = 0;
erts_aint_t io_tasks_executed = 0;
int fpe_was_unmasked;
erts_aint32_t state;
@@ -1595,6 +1616,7 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
fpe_was_unmasked = erts_block_fpe();
state = erts_atomic32_read_nob(&pp->state);
+ pp->reds = ERTS_PORT_REDS_EXECUTE;
goto begin_handle_tasks;
while (1) {
@@ -1621,14 +1643,14 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
switch (ptp->type) {
case ERTS_PORT_TASK_TIMEOUT:
- reds += ERTS_PORT_REDS_TIMEOUT;
+ reds = ERTS_PORT_REDS_TIMEOUT;
if (!(state & ERTS_PORT_SFLGS_DEAD)) {
DTRACE_DRIVER(driver_timeout, pp);
(*pp->drv_ptr->timeout)((ErlDrvData) pp->drv_data);
}
break;
case ERTS_PORT_TASK_INPUT:
- reds += ERTS_PORT_REDS_INPUT;
+ reds = ERTS_PORT_REDS_INPUT;
ASSERT((state & ERTS_PORT_SFLGS_DEAD) == 0);
DTRACE_DRIVER(driver_ready_input, pp);
/* NOTE some windows drivers use ->ready_input for input and output */
@@ -1637,7 +1659,7 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
io_tasks_executed++;
break;
case ERTS_PORT_TASK_OUTPUT:
- reds += ERTS_PORT_REDS_OUTPUT;
+ reds = ERTS_PORT_REDS_OUTPUT;
ASSERT((state & ERTS_PORT_SFLGS_DEAD) == 0);
DTRACE_DRIVER(driver_ready_output, pp);
(*pp->drv_ptr->ready_output)((ErlDrvData) pp->drv_data,
@@ -1645,7 +1667,7 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
io_tasks_executed++;
break;
case ERTS_PORT_TASK_EVENT:
- reds += ERTS_PORT_REDS_EVENT;
+ reds = ERTS_PORT_REDS_EVENT;
ASSERT((state & ERTS_PORT_SFLGS_DEAD) == 0);
DTRACE_DRIVER(driver_event, pp);
(*pp->drv_ptr->event)((ErlDrvData) pp->drv_data,
@@ -1657,22 +1679,22 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
ErtsProc2PortSigData *sigdp = &ptp->u.alive.td.psig.data;
ASSERT((state & ERTS_PORT_SFLGS_DEAD) == 0);
if (!pp->sched.taskq.bpq)
- reds += ptp->u.alive.td.psig.callback(pp,
- state,
- ERTS_PROC2PORT_SIG_EXEC,
- sigdp);
+ reds = ptp->u.alive.td.psig.callback(pp,
+ state,
+ ERTS_PROC2PORT_SIG_EXEC,
+ sigdp);
else {
ErlDrvSizeT size = erts_proc2port_sig_command_data_size(sigdp);
- reds += ptp->u.alive.td.psig.callback(pp,
- state,
- ERTS_PROC2PORT_SIG_EXEC,
- sigdp);
+ reds = ptp->u.alive.td.psig.callback(pp,
+ state,
+ ERTS_PROC2PORT_SIG_EXEC,
+ sigdp);
dequeued_proc2port_data(pp, size);
}
break;
}
case ERTS_PORT_TASK_DIST_CMD:
- reds += erts_dist_command(pp, CONTEXT_REDS-reds);
+ reds = erts_dist_command(pp, CONTEXT_REDS - pp->reds);
break;
default:
erl_exit(ERTS_ABORT_EXIT,
@@ -1697,7 +1719,10 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
vreds += ERTS_PORT_CALLBACK_VREDS;
reds += ERTS_PORT_CALLBACK_VREDS;
- if (reds >= CONTEXT_REDS)
+ pp->reds += reds;
+ reds = 0;
+
+ if (pp->reds >= CONTEXT_REDS)
break;
}
@@ -1721,6 +1746,8 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
active = finalize_exec(pp, &execq, processing_busy_q);
+ reds = pp->reds - vreds;
+
erts_port_release(pp);
*curr_port_pp = NULL;
@@ -1766,7 +1793,6 @@ erts_port_task_execute(ErtsRunQueue *runq, Port **curr_port_pp)
res = (erts_smp_atomic_read_nob(&erts_port_task_outstanding_io_tasks)
!= (erts_aint_t) 0);
- reds -= vreds;
runq->scheduler->reductions += reds;
ERTS_SMP_LC_ASSERT(erts_smp_lc_runq_is_locked(runq));
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 99766b7997..b73c883658 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -1199,6 +1199,7 @@ typedef struct {
int async; /* Asynchronous operation */
int pre_chk_sched_flags; /* Check sched flags before lock? */
int fpe_was_unmasked;
+ int reds_left_in;
} ErtsTryImmDrvCallState;
#define ERTS_INIT_TRY_IMM_DRV_CALL_STATE(C_P, PRT, SFLGS, PTS_FLGS, A, PRT_OP) \
@@ -1213,6 +1214,7 @@ static ERTS_INLINE ErtsTryImmDrvCallResult
try_imm_drv_call(ErtsTryImmDrvCallState *sp)
{
ErtsTryImmDrvCallResult res;
+ int reds_left_in;
erts_aint32_t invalid_state, invalid_sched_flags;
Port *prt = sp->port;
Process *c_p = sp->c_p;
@@ -1246,16 +1248,24 @@ try_imm_drv_call(ErtsTryImmDrvCallState *sp)
goto locked_fail;
}
- if (c_p) {
+
+ if (!c_p)
+ reds_left_in = CONTEXT_REDS/10;
+ else {
if (IS_TRACED_FL(c_p, F_TRACE_SCHED_PROCS))
trace_virtual_sched(c_p, am_out);
if (erts_system_profile_flags.runnable_procs
&& erts_system_profile_flags.exclusive)
profile_runnable_proc(c_p, am_inactive);
+ reds_left_in = ERTS_BIF_REDS_LEFT(c_p);
erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
}
+ ASSERT(0 <= reds_left_in && reds_left_in <= CONTEXT_REDS);
+ sp->reds_left_in = reds_left_in;
+ prt->reds = CONTEXT_REDS - reds_left_in;
+
ERTS_SMP_CHK_NO_PROC_LOCKS;
if (IS_TRACED_FL(prt, F_TRACE_SCHED_PORTS))
@@ -1276,10 +1286,12 @@ locked_fail:
static ERTS_INLINE void
finalize_imm_drv_call(ErtsTryImmDrvCallState *sp)
{
+ int reds;
Port *prt = sp->port;
Process *c_p = sp->c_p;
- erts_port_driver_callback_epilogue(prt, NULL);
+ reds = prt->reds;
+ reds += erts_port_driver_callback_epilogue(prt, NULL);
erts_unblock_fpe(sp->fpe_was_unmasked);
@@ -1294,6 +1306,12 @@ finalize_imm_drv_call(ErtsTryImmDrvCallState *sp)
if (c_p) {
erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
+ if (reds != (CONTEXT_REDS - sp->reds_left_in)) {
+ int bump_reds = reds - (CONTEXT_REDS - sp->reds_left_in);
+ ASSERT(bump_reds > 0);
+ BUMP_REDS(c_p, bump_reds);
+ }
+
if (IS_TRACED_FL(c_p, F_TRACE_SCHED_PROCS))
trace_virtual_sched(c_p, am_in);
if (erts_system_profile_flags.runnable_procs
diff --git a/erts/emulator/sys/win32/erl_win_dyn_driver.h b/erts/emulator/sys/win32/erl_win_dyn_driver.h
index 932c920595..a7c53c904d 100644
--- a/erts/emulator/sys/win32/erl_win_dyn_driver.h
+++ b/erts/emulator/sys/win32/erl_win_dyn_driver.h
@@ -48,6 +48,7 @@ WDD_TYPEDEF(ErlDrvSizeT, driver_vec_to_buf, (ErlIOVec *, char *, ErlDrvSizeT));
WDD_TYPEDEF(int, driver_set_timer, (ErlDrvPort, unsigned long));
WDD_TYPEDEF(int, driver_cancel_timer, (ErlDrvPort));
WDD_TYPEDEF(int, driver_read_timer, (ErlDrvPort, unsigned long *));
+WDD_TYPEDEF(int, erl_drv_consume_timeslice, (ErlDrvPort, int));
WDD_TYPEDEF(char *, erl_errno_id, (int));
WDD_TYPEDEF(void, set_busy_port, (ErlDrvPort, int));
WDD_TYPEDEF(void, set_port_control_flags, (ErlDrvPort, int));
@@ -164,6 +165,7 @@ typedef struct {
WDD_FTYPE(driver_set_timer) *driver_set_timer;
WDD_FTYPE(driver_cancel_timer) *driver_cancel_timer;
WDD_FTYPE(driver_read_timer) *driver_read_timer;
+ WDD_FTYPE(erl_drv_consume_timeslice) *erl_drv_consume_timeslice;
WDD_FTYPE(erl_errno_id) *erl_errno_id;
WDD_FTYPE(set_busy_port)* set_busy_port;
WDD_FTYPE(set_port_control_flags) *set_port_control_flags;
@@ -274,6 +276,7 @@ extern TWinDynDriverCallbacks WinDynDriverCallbacks;
#define driver_set_timer (WinDynDriverCallbacks.driver_set_timer)
#define driver_cancel_timer (WinDynDriverCallbacks.driver_cancel_timer)
#define driver_read_timer (WinDynDriverCallbacks.driver_read_timer)
+#define erl_drv_consume_timeslice (WinDynDriverCallbacks.erl_drv_consume_timeslice)
#define erl_errno_id (WinDynDriverCallbacks.erl_errno_id)
#define set_busy_port (WinDynDriverCallbacks.set_busy_port)
#define set_port_control_flags (WinDynDriverCallbacks.set_port_control_flags)
@@ -408,6 +411,7 @@ do { \
((W).driver_set_timer) = driver_set_timer; \
((W).driver_cancel_timer) = driver_cancel_timer; \
((W).driver_read_timer) = driver_read_timer; \
+((W).erl_drv_consume_timeslice) = erl_drv_consume_timeslice;\
((W).erl_errno_id) = erl_errno_id; \
((W).set_busy_port) = set_busy_port; \
((W).set_port_control_flags) = set_port_control_flags; \
diff --git a/erts/emulator/test/driver_SUITE.erl b/erts/emulator/test/driver_SUITE.erl
index dae36fed8f..dfba7d098f 100644
--- a/erts/emulator/test/driver_SUITE.erl
+++ b/erts/emulator/test/driver_SUITE.erl
@@ -78,7 +78,8 @@
otp_9302/1,
thr_free_drv/1,
async_blast/1,
- thr_msg_blast/1]).
+ thr_msg_blast/1,
+ consume_timeslice/1]).
-export([bin_prefix/2]).
@@ -149,7 +150,8 @@ all() ->
otp_9302,
thr_free_drv,
async_blast,
- thr_msg_blast].
+ thr_msg_blast,
+ consume_timeslice].
groups() ->
[{timer, [],
@@ -2073,10 +2075,329 @@ thr_msg_blast(Config) when is_list(Config) ->
Res
end.
+consume_timeslice(Config) when is_list(Config) ->
+ %%
+ %% Verify that erl_drv_consume_timeslice() works.
+ %%
+ %% The first four cases expect that the command signal is
+ %% delivered immediately, i.e., isn't scheduled. Since there
+ %% are no conflicts these signals should normally be delivered
+ %% immediately. However some builds and configurations may
+ %% schedule these ops anyway, in these cases we do not verify
+ %% scheduling counts.
+ %%
+ %% When signal is delivered immediately we must take into account
+ %% that process and port are "virtualy" scheduled out and in
+ %% in the trace generated.
+ %%
+ %% Port ! {_, {command, _}, and port_command() differs. The send
+ %% instruction needs to check if the caller is out of reductions
+ %% at the end of the instruction, since no erlang function call
+ %% is involved. Otherwise, a sequence of send instructions would
+ %% not be scheduled out even when out of reductions. port_commond()
+ %% doesn't do that since it will always (since R16A) be called via
+ %% the erlang wrappers in the erlang module.
+ %%
+ %% The last two cases tests scheduled operations. We create
+ %% a conflict by executing at the same time on different
+ %% schedulers. When only one scheduler we enable parallelism on
+ %% the port instead.
+ %%
+
+ Path = ?config(data_dir, Config),
+ erl_ddll:start(),
+ ok = load_driver(Path, consume_timeslice_drv),
+ Port = open_port({spawn, consume_timeslice_drv}, [{parallelism, false}]),
+
+ Parent = self(),
+ Go = make_ref(),
+
+ "enabled" = port_control(Port, $E, ""),
+ Proc1 = spawn_link(fun () ->
+ receive Go -> ok end,
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}}
+ end),
+ receive after 100 -> ok end,
+ count_pp_sched_start(),
+ Proc1 ! Go,
+ wait_command_msgs(Port, 10),
+ [{Port, Sprt1}, {Proc1, Sproc1}] = count_pp_sched_stop([Port, Proc1]),
+ case Sprt1 of
+ 10 ->
+ true = in_range(5, Sproc1-10, 7);
+ _ ->
+ case erlang:system_info(lock_checking) of
+ true -> ?t:format("Ignore bad sched count due to lock checking", []);
+ false -> ?t:fail({unexpected_sched_counts, Sprt1, Sproc1})
+ end
+ end,
+
+ "disabled" = port_control(Port, $D, ""),
+ Proc2 = spawn_link(fun () ->
+ receive Go -> ok end,
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}},
+ Port ! {Parent, {command, ""}}
+ end),
+ receive after 100 -> ok end,
+ count_pp_sched_start(),
+ Proc2 ! Go,
+ wait_command_msgs(Port, 10),
+ [{Port, Sprt2}, {Proc2, Sproc2}] = count_pp_sched_stop([Port, Proc2]),
+ case Sprt2 of
+ 10 ->
+ true = in_range(1, Sproc2-10, 2);
+ _ ->
+ case erlang:system_info(lock_checking) of
+ true -> ?t:format("Ignore bad sched count due to lock checking", []);
+ false -> ?t:fail({unexpected_sched_counts, Sprt2, Sproc2})
+ end
+ end,
+
+ "enabled" = port_control(Port, $E, ""),
+ Proc3 = spawn_link(fun () ->
+ receive Go -> ok end,
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, "")
+ end),
+ count_pp_sched_start(),
+ Proc3 ! Go,
+ wait_command_msgs(Port, 10),
+ [{Port, Sprt3}, {Proc3, Sproc3}] = count_pp_sched_stop([Port, Proc3]),
+ case Sprt3 of
+ 10 ->
+ true = in_range(5, Sproc3-10, 7);
+ _ ->
+ case erlang:system_info(lock_checking) of
+ true -> ?t:format("Ignore bad sched count due to lock checking", []);
+ false -> ?t:fail({unexpected_sched_counts, Sprt3, Sproc3})
+ end
+ end,
+
+ "disabled" = port_control(Port, $D, ""),
+ Proc4 = spawn_link(fun () ->
+ receive Go -> ok end,
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, ""),
+ port_command(Port, "")
+ end),
+ count_pp_sched_start(),
+ Proc4 ! Go,
+ wait_command_msgs(Port, 10),
+ [{Port, Sprt4}, {Proc4, Sproc4}] = count_pp_sched_stop([Port, Proc4]),
+ case Sprt4 of
+ 10 ->
+ true = in_range(1, Sproc4-10, 2);
+ _ ->
+ case erlang:system_info(lock_checking) of
+ true -> ?t:format("Ignore bad sched count due to lock checking", []);
+ false -> ?t:fail({unexpected_sched_counts, Sprt4, Sproc4})
+ end
+ end,
+
+ SOnl = erlang:system_info(schedulers_online),
+ %% If only one scheduler use port with parallelism set to true,
+ %% in order to trigger scheduling of command signals
+ Port2 = case SOnl of
+ 1 ->
+ Port ! {self(), close},
+ receive {Port, closed} -> ok end,
+ open_port({spawn, consume_timeslice_drv},
+ [{parallelism, true}]);
+ _ ->
+ process_flag(scheduler, 1),
+ 1 = erlang:system_info(scheduler_id),
+ Port
+ end,
+ count_pp_sched_start(),
+ "enabled" = port_control(Port2, $E, ""),
+ W5 = case SOnl of
+ 1 ->
+ false;
+ _ ->
+ W1= spawn_opt(fun () ->
+ 2 = erlang:system_info(scheduler_id),
+ "sleeped" = port_control(Port2, $S, "")
+ end, [link,{scheduler,2}]),
+ receive after 100 -> ok end,
+ W1
+ end,
+ Proc5 = spawn_opt(fun () ->
+ receive Go -> ok end,
+ 1 = erlang:system_info(scheduler_id),
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}}
+ end, [link,{scheduler,1}]),
+ receive after 100 -> ok end,
+ Proc5 ! Go,
+ wait_procs_exit([W5, Proc5]),
+ wait_command_msgs(Port2, 10),
+ [{Port2, Sprt5}, {Proc5, Sproc5}] = count_pp_sched_stop([Port2, Proc5]),
+ true = in_range(2, Sproc5, 3),
+ true = in_range(7, Sprt5, 20),
+
+ count_pp_sched_start(),
+ "disabled" = port_control(Port2, $D, ""),
+ W6 = case SOnl of
+ 1 ->
+ false;
+ _ ->
+ W2= spawn_opt(fun () ->
+ 2 = erlang:system_info(scheduler_id),
+ "sleeped" = port_control(Port2, $S, "")
+ end, [link,{scheduler,2}]),
+ receive after 100 -> ok end,
+ W2
+ end,
+ Proc6 = spawn_opt(fun () ->
+ receive Go -> ok end,
+ 1 = erlang:system_info(scheduler_id),
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}},
+ Port2 ! {Parent, {command, ""}}
+ end, [link,{scheduler,1}]),
+ receive after 100 -> ok end,
+ Proc6 ! Go,
+ wait_procs_exit([W6, Proc6]),
+ wait_command_msgs(Port2, 10),
+ [{Port2, Sprt6}, {Proc6, Sproc6}] = count_pp_sched_stop([Port2, Proc6]),
+ true = in_range(2, Sproc6, 3),
+ true = in_range(3, Sprt6, 6),
+
+ process_flag(scheduler, 0),
+
+ Port2 ! {self(), close},
+ receive {Port2, closed} -> ok end,
+ ok.
+
+wait_command_msgs(_, 0) ->
+ ok;
+wait_command_msgs(Port, N) ->
+ receive
+ {Port, command} ->
+ wait_command_msgs(Port, N-1)
+ end.
+
+in_range(Low, Val, High) when is_integer(Low),
+ is_integer(Val),
+ is_integer(High),
+ Low =< Val,
+ Val =< High ->
+ true;
+in_range(Low, Val, High) when is_integer(Low),
+ is_integer(Val),
+ is_integer(High) ->
+ false.
+
+count_pp_sched_start() ->
+ erlang:trace(all, true, [running_procs, running_ports, {tracer, self()}]),
+ ok.
+
+count_pp_sched_stop(Ps) ->
+ Td = erlang:trace_delivered(all),
+ erlang:trace(all, false, [running_procs, running_ports, {tracer, self()}]),
+ PNs = lists:map(fun (P) -> {P, 0} end, Ps),
+ receive {trace_delivered, all, Td} -> ok end,
+ Res = count_proc_sched(Ps, PNs),
+ ?t:format("Scheduling counts: ~p~n", [Res]),
+ erlang:display({scheduling_counts, Res}),
+ Res.
+
+do_inc_pn(_P, []) ->
+ throw(undefined);
+do_inc_pn(P, [{P,N}|PNs]) ->
+ [{P,N+1}|PNs];
+do_inc_pn(P, [PN|PNs]) ->
+ [PN|do_inc_pn(P, PNs)].
+
+inc_pn(P, PNs) ->
+ try
+ do_inc_pn(P, PNs)
+ catch
+ throw:undefined -> PNs
+ end.
+
+count_proc_sched(Ps, PNs) ->
+ receive
+ TT when element(1, TT) == trace, element(3, TT) == in ->
+% erlang:display(TT),
+ count_proc_sched(Ps, inc_pn(element(2, TT), PNs));
+ TT when element(1, TT) == trace, element(3, TT) == out ->
+ count_proc_sched(Ps, PNs)
+ after 0 ->
+ PNs
+ end.
+
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Utilities
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%flush_msgs() ->
+% receive
+% M ->
+% erlang:display(M),
+% flush_msgs()
+% after 0 ->
+% ok
+% end.
+
+wait_procs_exit([]) ->
+ ok;
+wait_procs_exit([P|Ps]) when is_pid(P) ->
+ Mon = erlang:monitor(process, P),
+ receive
+ {'DOWN', Mon, process, P, _} ->
+ wait_procs_exit(Ps)
+ end;
+wait_procs_exit([_|Ps]) ->
+ wait_procs_exit(Ps).
+
get_port_msg(Port, Timeout) ->
receive
{Port, What} ->
diff --git a/erts/emulator/test/driver_SUITE_data/Makefile.src b/erts/emulator/test/driver_SUITE_data/Makefile.src
index b667dff6b6..1fedd72200 100644
--- a/erts/emulator/test/driver_SUITE_data/Makefile.src
+++ b/erts/emulator/test/driver_SUITE_data/Makefile.src
@@ -15,7 +15,8 @@ MISC_DRVS = outputv_drv@dll@ \
otp_9302_drv@dll@ \
thr_free_drv@dll@ \
async_blast_drv@dll@ \
- thr_msg_blast_drv@dll@
+ thr_msg_blast_drv@dll@ \
+ consume_timeslice_drv@dll@
SYS_INFO_DRVS = sys_info_base_drv@dll@ \
sys_info_prev_drv@dll@ \
diff --git a/erts/emulator/test/driver_SUITE_data/consume_timeslice_drv.c b/erts/emulator/test/driver_SUITE_data/consume_timeslice_drv.c
new file mode 100644
index 0000000000..6b0c4cf37d
--- /dev/null
+++ b/erts/emulator/test/driver_SUITE_data/consume_timeslice_drv.c
@@ -0,0 +1,172 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2012. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#include "erl_driver.h"
+#ifdef __WIN32__
+#include <windows.h>
+#else
+#include <unistd.h>
+#endif
+#include <stdio.h>
+#include <string.h>
+
+static void stop(ErlDrvData drv_data);
+static ErlDrvData start(ErlDrvPort port,
+ char *command);
+static void output(ErlDrvData drv_data,
+ char *buf, ErlDrvSizeT len);
+static ErlDrvSSizeT control(ErlDrvData drv_data,
+ unsigned int command,
+ char *buf, ErlDrvSizeT len,
+ char **rbuf, ErlDrvSizeT rlen);
+
+static ErlDrvEntry consume_timeslice_drv_entry = {
+ NULL /* init */,
+ start,
+ stop,
+ output,
+ NULL /* ready_input */,
+ NULL /* ready_output */,
+ "consume_timeslice_drv",
+ NULL /* finish */,
+ NULL /* handle */,
+ control,
+ NULL /* timeout */,
+ NULL /* outputv */,
+ NULL /* ready_async */,
+ NULL /* flush */,
+ NULL /* call */,
+ NULL /* event */,
+ ERL_DRV_EXTENDED_MARKER,
+ ERL_DRV_EXTENDED_MAJOR_VERSION,
+ ERL_DRV_EXTENDED_MINOR_VERSION,
+ ERL_DRV_FLAG_USE_PORT_LOCKING,
+ NULL /* handle2 */,
+ NULL /* handle_monitor */
+};
+
+typedef struct {
+ ErlDrvPort port;
+ ErlDrvTermData tport;
+ ErlDrvTermData cmd_msg[6];
+ int consume_timeslice;
+} consume_timeslice_data_t;
+
+
+DRIVER_INIT(consume_timeslice_drv)
+{
+ return &consume_timeslice_drv_entry;
+}
+
+static void stop(ErlDrvData drv_data)
+{
+ driver_free((void *) drv_data);
+}
+
+static ErlDrvData start(ErlDrvPort port,
+ char *command)
+{
+ consume_timeslice_data_t *ctsd;
+
+ ctsd = driver_alloc(sizeof(consume_timeslice_data_t));
+ if (!ctsd)
+ return ERL_DRV_ERROR_GENERAL;
+
+ ctsd->port = port;
+ ctsd->tport = driver_mk_port(port);
+ ctsd->consume_timeslice = 0;
+
+ ctsd->cmd_msg[0] = ERL_DRV_PORT;
+ ctsd->cmd_msg[1] = ctsd->tport;
+ ctsd->cmd_msg[2] = ERL_DRV_ATOM;
+ ctsd->cmd_msg[3] = driver_mk_atom("command");
+ ctsd->cmd_msg[4] = ERL_DRV_TUPLE;
+ ctsd->cmd_msg[5] = (ErlDrvTermData) 2;
+
+ return (ErlDrvData) ctsd;
+}
+
+static void output(ErlDrvData drv_data,
+ char *buf, ErlDrvSizeT len)
+{
+ consume_timeslice_data_t *ctsd = (consume_timeslice_data_t *) drv_data;
+ int res;
+
+ if (ctsd->consume_timeslice) {
+ int res = erl_drv_consume_timeslice(ctsd->port, 50);
+ if (res < 0) {
+ driver_failure_atom(ctsd->port, "erl_drv_consume_timeslice() failed");
+ return;
+ }
+ }
+
+ res = erl_drv_output_term(ctsd->tport,
+ ctsd->cmd_msg,
+ sizeof(ctsd->cmd_msg)/sizeof(ErlDrvTermData));
+ if (res <= 0) {
+ driver_failure_atom(ctsd->port, "erl_drv_output_term() failed");
+ return;
+ }
+}
+static ErlDrvSSizeT control(ErlDrvData drv_data,
+ unsigned int command,
+ char *buf, ErlDrvSizeT len,
+ char **rbuf, ErlDrvSizeT rlen)
+{
+ consume_timeslice_data_t *ctsd = (consume_timeslice_data_t *) drv_data;
+ int res;
+ char *res_str;
+ ErlDrvSSizeT res_len;
+
+ switch (command) {
+ case 'E':
+ ctsd->consume_timeslice = 1;
+ res_str = "enabled";
+ break;
+ case 'D':
+ ctsd->consume_timeslice = 0;
+ res_str = "disabled";
+ break;
+ case 'S':
+#ifdef __WIN32__
+ Sleep((DWORD) 1000);
+#else
+ sleep(1);
+#endif
+ res_str = "sleeped";
+ break;
+ default:
+ res_str = "what?";
+ break;
+ }
+
+ res_len = strlen(res_str);
+ if (res_len > rlen) {
+ char *abuf = driver_alloc(sizeof(char)*res_len);
+ if (!abuf) {
+ driver_failure_atom(ctsd->port, "driver_alloc() failed");
+ return 0;
+ }
+ *rbuf = abuf;
+ }
+
+ memcpy((void *) *rbuf, (void *) res_str, res_len);
+
+ return res_len;
+}