diff options
Diffstat (limited to 'erts')
| -rw-r--r-- | erts/emulator/test/scheduler_SUITE.erl | 78 |
1 files changed, 62 insertions, 16 deletions
diff --git a/erts/emulator/test/scheduler_SUITE.erl b/erts/emulator/test/scheduler_SUITE.erl index b178dede5b..885298ce34 100644 --- a/erts/emulator/test/scheduler_SUITE.erl +++ b/erts/emulator/test/scheduler_SUITE.erl @@ -807,21 +807,31 @@ update_cpu_info(Config) when is_list(Config) -> %% Nothing much to test; just a smoke test ok; Onln0 -> - %% unset least significant bit - Aff = (OldAff band (OldAff - 1)), - set_affinity_mask(Aff), - Onln1 = Avail - 1, - case adjust_schedulers_online() of - {Onln0, Onln1} -> - Onln1 = erlang:system_info(schedulers_online), - receive after 500 -> ok end, - io:format("TEST - Affinity mask: ~p - Schedulers online: ~p - Scheduler bindings: ~p~n", - [Aff, Onln1, erlang:system_info(scheduler_bindings)]), - unchanged = adjust_schedulers_online(), - ok; - Fail -> - ct:fail(Fail) - end + Cpus = bits_in_mask(OldAff), + RmCpus = case Cpus > Onln0 of + true -> Cpus - Onln0 + 1; + false -> Onln0 - Cpus + 1 + end, + Onln1 = Cpus - RmCpus, + case Onln1 > 0 of + false -> + %% Nothing much to test; just a smoke test + ok; + true -> + Aff = restrict_affinity_mask(OldAff, RmCpus), + set_affinity_mask(Aff), + case adjust_schedulers_online() of + {Onln0, Onln1} -> + Onln1 = erlang:system_info(schedulers_online), + receive after 500 -> ok end, + io:format("TEST - Affinity mask: ~p - Schedulers online: ~p - Scheduler bindings: ~p~n", + [Aff, Onln1, erlang:system_info(scheduler_bindings)]), + unchanged = adjust_schedulers_online(), + ok; + Fail -> + ct:fail(Fail) + end + end end after set_affinity_mask(OldAff), @@ -835,13 +845,49 @@ update_cpu_info(Config) when is_list(Config) -> end end. +bits_in_mask(Mask) -> + bits_in_mask(Mask, 0, 0). + +bits_in_mask(0, Shift, N) -> + N; +bits_in_mask(Mask, Shift, N) -> + case Mask band (1 bsl Shift) of + 0 -> bits_in_mask(Mask, Shift+1, N); + _ -> bits_in_mask(Mask band (bnot (1 bsl Shift)), + Shift+1, N+1) + end. + +restrict_affinity_mask(Mask, N) -> + try + restrict_affinity_mask(Mask, 0, N) + catch + throw : Reason -> + exit({Reason, Mask, N}) + end. + +restrict_affinity_mask(Mask, _Shift, 0) -> + Mask; +restrict_affinity_mask(0, _Shift, _N) -> + throw(overresticted_affinity_mask); +restrict_affinity_mask(Mask, Shift, N) -> + case Mask band (1 bsl Shift) of + 0 -> restrict_affinity_mask(Mask, Shift+1, N); + _ -> restrict_affinity_mask(Mask band (bnot (1 bsl Shift)), + Shift+1, N-1) + end. + adjust_schedulers_online() -> case erlang:system_info(update_cpu_info) of unchanged -> unchanged; changed -> Avail = erlang:system_info(logical_processors_available), - {erlang:system_flag(schedulers_online, Avail), Avail} + Scheds = erlang:system_info(schedulers), + SOnln = case Avail > Scheds of + true -> Scheds; + false -> Avail + end, + {erlang:system_flag(schedulers_online, SOnln), SOnln} end. read_affinity(Data) -> |