Re: nptl/tst-eintr1.c test question

[Stefan Liebler <stli@linux.vnet.ibm.com>]

On 12/16/2016 12:02 AM, Steve Ellcey wrote:
> I was wondering if anyone else is having problems with nptl/tst-eintr1?
> This test is known to fail on some kernels and there is a comment about
> it on the glibc wiki.
>
> https://sourceware.org/glibc/wiki/Testing/Testsuite#Known_testsuite_failures
>
> The problem I have is that when this test fails for me on my aarch64 box
> it doesn't just result in a failed test, it aborts the whole 'make check'
> process and I don't get any results printed out.  I was wondering if there
> was some way to make this test not run on some platforms (and how I might
> identify what those platforms were).
>
> Maybe something like:
>
> #define BAD_KERNEL (defined (__ARM_ARCH_8A))
> #if BAD_KERNEL
> static int do_fail (void) { return 1; }
> # define TEST_FUNCTION do_fail ()
> #else
> # define TEST_FUNCTION do_test ()
> #endif
>
> I don't know if this test fails on all aarch8/8A platforms, I just know
> that it fails for me, so I am not sure what a good way to set BAD_KERNEL
> would be.
>
> Any thoughts?
>
> FYI: The failure I get is due to to many forks causing the make process(es) to
> abort:
>
> ../scripts/evaluate-test.sh nptl/tst-eintr1 $? false false > /home/ubuntu/sellcey/glibc-patched/obj-glibc64/nptl/tst-eintr1.test-result
> /bin/sh: 2: Cannot fork
> ../Rules:241: recipe for target '/home/ubuntu/sellcey/glibc-patched/obj-glibc64/nptl/tst-eintr1.out' failed
> make[2]: *** [/home/ubuntu/sellcey/glibc-patched/obj-glibc64/nptl/tst-eintr1.out] Error 2
> make[2]: Leaving directory '/home/ubuntu/sellcey/glibc-patched/src/glibc/nptl'
> Makefile:215: recipe for target 'nptl/tests' failed
> make[1]: *** [nptl/tests] Error 2
> make[1]: Leaving directory '/home/ubuntu/sellcey/glibc-patched/src/glibc'
> Makefile:9: recipe for target 'check' failed
> make: *** [check] Error 2
>
>
> Steve Ellcey
> sellcey@caviumnetworks.com
>
Hi Steve,

I recognize such EAGAIN failures on s390, too.
In my case, I can only see them if cgroups configuration has limited 
pids.max. Otherwise, there is no issue.

If pthread_create fails with EAGAIN and I then query the number of 
processes via e.g. sysinfo(), I recognize a small number of processes. 
If I afterwards try pthread_create() again, it fails with EAGAIN, too.

The threads have been exited, but the kernel releases the PIDs only 
interval-based. On at least s390 this interval is longer than on e.g. x86.

Bye
Stefan