On 17-Dec-21 6:29 PM, Stephen Hemminger wrote:
If DPDK is built with thread sanitizer it reports a race
in setting of multiprocess file descriptor. The fix is to
use atomic operations when updating mp_fd.
Simple example:
$ dpdk-testpmd -l 1-3 --no-huge
...
EAL: Error - exiting with code: 1
Cause: Creation of mbuf pool for socket 0 failed: Cannot allocate memory
==================
WARNING: ThreadSanitizer: data race (pid=83054)
Write of size 4 at 0x55e3b7fce450 by main thread:
#0 rte_mp_channel_cleanup <null> (dpdk-testpmd+0x160d79c)
#1 rte_eal_cleanup <null> (dpdk-testpmd+0x1614fb5)
#2 rte_exit <null> (dpdk-testpmd+0x15ec97a)
#3 mbuf_pool_create.cold <null> (dpdk-testpmd+0x242e1a)
#4 main <null> (dpdk-testpmd+0x5ab05d)
Previous read of size 4 at 0x55e3b7fce450 by thread T2:
#0 mp_handle <null> (dpdk-testpmd+0x160c979)
#1 ctrl_thread_init <null> (dpdk-testpmd+0x15ff76e)
As if synchronized via sleep:
#0 nanosleep
../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:362
(libtsan.so.0+0x5cd8e)
#1 get_tsc_freq <null> (dpdk-testpmd+0x1622889)
#2 set_tsc_freq <null> (dpdk-testpmd+0x15ffb9c)
#3 rte_eal_timer_init <null> (dpdk-testpmd+0x1622a34)
#4 rte_eal_init.cold <null> (dpdk-testpmd+0x26b314)
#5 main <null> (dpdk-testpmd+0x5aab45)
Location is global 'mp_fd' of size 4 at 0x55e3b7fce450
(dpdk-testpmd+0x0000027c7450)
Thread T2 'rte_mp_handle' (tid=83057, running) created by main thread at:
#0 pthread_create
../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962
(libtsan.so.0+0x58ba2)
#1 rte_ctrl_thread_create <null> (dpdk-testpmd+0x15ff870)
#2 rte_mp_channel_init.cold <null> (dpdk-testpmd+0x269986)
#3 rte_eal_init <null> (dpdk-testpmd+0x1615b28)
#4 main <null> (dpdk-testpmd+0x5aab45)
SUMMARY: ThreadSanitizer: data race
(/home/shemminger/DPDK/main/build/app/dpdk-testpmd+0x160d79c) in
rte_mp_channel_cleanup
==================
ThreadSanitizer: reported 1 warnings
Fixes: bacaa2754017 ("eal: add channel for multi-process communication")
Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
---
v2 - fix the mp socket bind
Acked-by: Anatoly Burakov <anatoly.bura...@intel.com>
--
Thanks,
Anatoly