benn/lumiera_
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

clarify (and treat) the race; considered to be test-only

Browse source 
After removing the explicit locking, there is a small
race in case of a "floundering" (simulated) subsystem:
the starting context may go away before the child thread
actually teminates. I consider this a shortcoming of
this test fixture, which isn't intended to be an example
of a real world subsystem, but rather focusses on
error detection within the subsystem runner.
This commit is contained in:
Fischlurch 2010-02-07 17:31:28 +01:00
parent 8ad3bf1736
commit 5386fe6fbc
1 changed files with 21 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

28
tests/lib/subsystem-runner-test.cpp
View file

@ -61,6 +61,13 @@ namespace test {
* shutdown request every XX milliseconds */
const uint TICK_DURATION_ms = 5;
/** due to a shortcoming of this test fixture,
* a floundering subsystem continues to run for
* a short time after the sync barrier.
* Relevant for singleSubsys_start_failure().
*/
const uint DELAY_FOR_FLOUNDERING_THRAD_ms = 20;
/** dummy options just to be ignored */
util::Cmdline dummyArgs ("");
lumiera::Option dummyOpt (dummyArgs);
@ -75,12 +82,9 @@ namespace test {
/**
* A simulated "Lumiera Subsystem".
* It is capable of starting a separate thread,
* which may terminate regularly after a random
* time, or may fail in various ways.
* The behaviour is controlled by a number of
* definitions, given at construction in
* logic predicate notation.
* It is capable of starting a separate thread, which may terminate regularly
* after a random time, or may fail in various ways. The behaviour is controlled
* by a number of definitions, given at construction in logic predicate notation.
*/
class MockSys
: public lumiera::Subsys
@ -262,7 +266,7 @@ namespace test {
run (Arg)
{
singleSubsys_complete_cycle();
singleSubsys_start_failure(); ////////////////////////////TODO: Valgrind logs an invalid read from here here, at line 172
singleSubsys_start_failure();
singleSubsys_emegency_exit();
dependentSubsys_complete_cycle();
@ -289,6 +293,15 @@ namespace test {
}
/** @note as this test focuses on the SubsystemRunner, the mock subsystem
* is implemented rather simplistic. Especially, there is a race when a
* subsystem is configured to "fail" -- because in this case the starting
* context may go away before the remainder of the subsystem thread has
* executed after the sync() barrier. Especially in this case, no MockSys
* actually starts without failure, and thus the SubsystemRunner::wait()
* has no guarding effect. This can be considered a shortcoming of the
* test fixture; a well behaved subsystem won't just go away...
*/
void
singleSubsys_start_failure()
{
@ -306,6 +319,7 @@ namespace test {
VERIFY_ERROR (LOGIC, runner.maybeRun (unit3) ); // incorrect behaviour trapped
VERIFY_ERROR (LOGIC, runner.maybeRun (unit4) ); // detected that the subsystem didn't come up
usleep (DELAY_FOR_FLOUNDERING_THRAD_ms * 1000); // preempt to allow unit4 to go away
runner.wait();
ASSERT (!unit1.isRunning());