[dpdk-dev] DPDK with -fsanitize=thread failure

[Stephen Hemminger <stephen@networkplumber.org>]

Tried running DPDK under Address Sanitizer with the thread data race
option, and ran into something that needs some discussion.
Is this just an ASAN bug?

The fatal log is:

==================
WARNING: ThreadSanitizer: data race (pid=28275)
  Write of size 1 at 0xfffff5000580 by main thread:
    #0 pthread_barrier_destroy <null> (libtsan.so.0+0x314b3)
    #1 rte_ctrl_thread_create <null> (librte_eal.so.20.0+0x2f9db)
    #2 rte_eal_intr_init <null> (librte_eal.so.20.0+0x1e573)
    #3 rte_eal_init <null> (librte_eal.so.20.0+0xcb9b)
    #4 <null> <null> (dpdk-backplane+0xb2ab)
    #5 main <null> (dpdk-backplane+0xa1ab)

  Previous read of size 1 at 0xfffff5000580 by thread T3:
    #0 pthread_barrier_wait <null> (libtsan.so.0+0x315cf)
    #1 rte_thread_init <null> (librte_eal.so.20.0+0x2f44f)
    #2 <null> <null> (libtsan.so.0+0x2cc63)

  Location is heap block of size 48 at 0xfffff5000570 allocated by main thread:
    #0 malloc <null> (libtsan.so.0+0x2e4ef)
    #1 rte_ctrl_thread_create <null> (librte_eal.so.20.0+0x2f873)
    #2 rte_eal_intr_init <null> (librte_eal.so.20.0+0x1e573)
    #3 rte_eal_init <null> (librte_eal.so.20.0+0xcb9b)
    #4 <null> <null> (dpdk-backplane+0xb2ab)
    #5 main <null> (dpdk-backplane+0xa1ab)

  Thread T3 'eal-intr-thread' (tid=28284, running) created by main thread at:
    #0 pthread_create <null> (libtsan.so.0+0x2f5a7)
    #1 rte_ctrl_thread_create <null> (librte_eal.so.20.0+0x2f8bb)
    #2 rte_eal_intr_init <null> (librte_eal.so.20.0+0x1e573)
    #3 rte_eal_init <null> (librte_eal.so.20.0+0xcb9b)
    #4 <null> <null> (dpdk-backplane+0xb2ab)
    #5 main <null> (dpdk-backplane+0xa1ab)

SUMMARY: ThreadSanitizer: data race (/lib/libtsan.so.0+0x314b3) in pthread_barrier_destroy
==================


The code is:

	pthread_barrier_init(&params->configured, NULL, 2);
	ret = pthread_create(thread, attr, ctrl_thread_init, (void *)params);
...
	ret = pthread_barrier_wait(&params->configured);
	if (ret == PTHREAD_BARRIER_SERIAL_THREAD) {
		pthread_barrier_destroy(&params->configured);