----- Original Message -----
> From: "Kang Kai" <[email protected]>
> To: "Jan Stancek" <[email protected]>, [email protected]
> Cc: [email protected], "Zhenfeng Zhao"
> <[email protected]>
> Sent: Thursday, 23 August, 2012 8:21:43 AM
> Subject: Re: [LTP] [PATCH] pthread_detach/4-3: workaround for segment fault
>
> On 2012年08月22日 22:20, Jan Stancek wrote:
> > On 08/22/2012 10:58 AM, Jan Stancek wrote:
> >>
> >> ----- Original Message -----
> >>> From: "Kang Kai"<[email protected]>
> >>> To: "Jan Stancek"<[email protected]>
> >>> Cc: [email protected], [email protected],
> >>> "Zhenfeng Zhao"<[email protected]>
> >>> Sent: Wednesday, 22 August, 2012 10:28:59 AM
> >>> Subject: Re: [LTP] [PATCH] pthread_detach/4-3: workaround for
> >>> segment fault
> >>> Hi Jan,
> >>>
> >>>> Is the above output from mips or x86_64?
> >>>> Are you running it as root user?
> >>> This was tested on x86_64 with unprivileged user. I retest it
> >>> with
> >>> root
> >>> and test passes.
> >> Your unprivileged user is hitting some resource limit, I'd be
> >> interested
> >> to see how many threads are actually running at the same time.
> >>
> >>> It passes on routerstation(mips) with your patch too.
> >>> So it looks like a race condition issue about stack attribute
> >>> between
> >>> threads, right?
> >> I think so. We can try different way of signalling when threaded()
> >> is done
> >> and try it again with all scenarios.
> > I think this testcase is broken in more than 1 way. At least on my
> > setup, I don't see
> > a single pthread_detach() while signals are firing - which is
> > exactly goal of this test.
> >
> > With following change:
> >
> > diff --git
> > a/testcases/open_posix_testsuite/conformance/interfaces/pthread_detach/4-3.c
> > b/testcases/open_posix_testsuite/conforman
> > index dfa6e19..48e1343 100644
> > ---
> > a/testcases/open_posix_testsuite/conformance/interfaces/pthread_detach/4-3.c
> > +++
> > b/testcases/open_posix_testsuite/conformance/interfaces/pthread_detach/4-3.c
> > @@ -277,6 +276,7 @@ int main(int argc, char *argv[])
> > do_it1 = 0;
> > } while (do_it1);
> >
> > + output(" %d thread detached while signals were firing.\n",
> > count_ope);
> > sleep(1);
> >
> > do {
> >
> > I get:
> > [16:11:23] 1 thread detached while signals are firing.
> > [16:11:24]Test executed successfully.
> > [16:11:24] 77865 thread detached.
> >
> > and that reported "1" is how many threads attempted to call
> > pthread_detach, not how many actually
> > succeeded. Signals are firing so frequently that threaded() can't
> > progress at all.
> Then how do we fix this case? sync sending the signals with
> pthread_detach?
I was thinking usleep(sleep_time) that progressively increases. So it
starts firing signals as quickly as it can and slows down over time.
Each pthread_detach() would reset the sleep_time.
As for our original issue, idea I'm playing with is:
main (procA) - do_child (procB) - send_sig (thread)
\
test (thread) - threaded (detached thread)
- turn 'while' in test() to single 'for' loop
- loop in main, fork and call do_child, wait for child to finish
This way we can be sure, that we don't reuse same stack for multiple threads,
and we can also be sure, there won't be more than NSCENAR threads, so
unprivileged
user should not run out of resources.
Regards,
Jan
>
> Wanlong, any comments?
>
> Thanks,
> Kai
>
> >
> > Regards,
> > Jan
> >
>
>
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