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multithreading: fix spinlock in ecl_wait_on_timed

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process.woken_up was not set to nil before calling condition. This could
lead to threads not waiting correctly on barriers and consequently to
mp:process-join returning earlier than it should.
This commit is contained in:
Marius Gerbershagen 2019-08-25 20:51:02 +02:00
parent 14a94c2b0e
commit 0080acd4ce
2 changed files with 10 additions and 10 deletions
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2
src/c/threads/barrier.d
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@ -34,7 +34,7 @@ ecl_make_barrier(cl_object name, cl_index count)
@(defun mp::make-barrier (count &key name)
@
if (count == ECL_T)
count = ecl_make_fixnum(MOST_POSITIVE_FIXNUM);
count = ecl_make_fixnum(MOST_POSITIVE_FIXNUM);
@(return ecl_make_barrier(name, fixnnint(count)));
@)

18
src/c/threads/queue.d
View file

@ -135,14 +135,6 @@ ecl_wait_on_timed(cl_env_ptr env, cl_object (*condition)(cl_env_ptr, cl_object),
struct ecl_timeval start;
ecl_get_internal_real_time(&start);
/* This spinlock is here because the default path (fair) is
* too slow */
for (iteration = 0; iteration < 10; iteration++) {
cl_object output = condition(the_env,o);
if (output != ECL_NIL)
return output;
}
/* 0) We reserve a record for the queue. In order to avoid
* using the garbage collector, we reuse records */
record = own_process->process.queue_record;
@ -162,14 +154,22 @@ ecl_wait_on_timed(cl_env_ptr env, cl_object (*condition)(cl_env_ptr, cl_object),
ecl_bds_bind(the_env, @'ext::*interrupts-enabled*', ECL_T);
ecl_check_pending_interrupts(the_env);
/* This spinlock is here because the default path (fair) is
* too slow */
for (iteration = 0; iteration < 10; iteration++) {
if (!Null(output = condition(the_env,o)))
break;
}
/* 3) Unlike the sigsuspend() implementation, this
* implementation does not block signals and the
* wakeup event might be lost before the sleep
* function is invoked. We must thus spin over short
* intervals of time to ensure that we check the
* condition periodically. */
while (Null(output = condition(the_env, o))) {
while (Null(output)) {
ecl_musleep(waiting_time(iteration++, &start), 1);
output = condition(the_env, o);
}
ecl_bds_unwind1(the_env);
} ECL_UNWIND_PROTECT_EXIT {