"Van Haaren, Harry" <harry.van.haa...@intel.com> writes: >> -----Original Message----- >> From: David Marchand <david.march...@redhat.com> >> Sent: Tuesday, March 10, 2020 4:31 PM >> To: Van Haaren, Harry <harry.van.haa...@intel.com> >> Cc: dev <dev@dpdk.org>; Aaron Conole <acon...@redhat.com> >> Subject: Re: [PATCH] eal/service: fix exit by resetting service lcores >> >> On Tue, Mar 10, 2020 at 2:32 PM Harry van Haaren >> <harry.van.haa...@intel.com> wrote: >> > >> > This commit releases all service cores from thier role, >> > returning them to ROLE_RTE on rte_service_finalize(). >> > >> > This may fix an issue relating to the service cores causing >> > a race-condition on eal_cleanup(), where the service core >> > could still be executing while the main thread has already >> > free-d the service memory, leading to a segfault. >> >> Adding rte_service_lcore_reset_all() just tells a (remaining) service >> lcore to quit its loop, but does not close the race on lcore_states. >> >> The backtrace shows the same. >> >> (gdb) bt full >> #0 rte_service_runner_func (arg=<optimized out>) at >> ../lib/librte_eal/common/rte_service.c:455 >> service_mask = 1 >> i = <optimized out> >> lcore = 1 >> cs = 0x1003ea200 >> #1 0x00007ffff72030ef in eal_thread_loop (arg=<optimized out>) at >> ../lib/librte_eal/linux/eal/eal_thread.c:153 >> fct_arg = <optimized out> >> c = 0 '\000' >> n = <optimized out> >> ret = <optimized out> >> lcore_id = <optimized out> >> thread_id = 140737203603200 >> m2s = 14 >> s2m = 22 >> cpuset = "1", '\000' <repeats 175 times>, >> "\200\000\000\000\000\000\000\000\221\354e\360\377\177", '\000' >> <repeats 65 times> >> __func__ = "eal_thread_loop" >> #2 0x00007ffff065ddd5 in start_thread () from /lib64/libpthread.so.0 >> No symbol table info available. >> #3 0x00007ffff038702d in clone () from /lib64/libc.so.6 >> No symbol table info available. >> >> >> I added a rte_eal_mp_wait_lcore(), to ensure that each service lcore >> _did_ quit its loop. >> @@ -123,6 +123,7 @@ rte_service_finalize(void) >> return; >> >> rte_service_lcore_reset_all(); >> + rte_eal_mp_wait_lcore(); >> >> rte_free(rte_services); >> rte_free(lcore_states); >> >> >> I can't reproduce with this. > > OK - that's good news, thanks for the quick testing & feedback. > > Agree with your analysis of the above, indeed waiting for the cores > explicitly seems the right solution to remove the race. > > Will I spin up a v2 patchset with your co-authored-by added and the above > change included?
Please spin the v2 - I am currently testing with David's incremental on my setup now.
