diff options
Diffstat (limited to 'erts/emulator/test/scheduler_SUITE.erl')
| -rw-r--r-- | erts/emulator/test/scheduler_SUITE.erl | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/erts/emulator/test/scheduler_SUITE.erl b/erts/emulator/test/scheduler_SUITE.erl index 4f4458802c..06442bfad6 100644 --- a/erts/emulator/test/scheduler_SUITE.erl +++ b/erts/emulator/test/scheduler_SUITE.erl @@ -47,6 +47,7 @@ scheduler_bind/1, scheduler_bind_types/1, cpu_topology/1, + update_cpu_info/1, sct_cmd/1, sbt_cmd/1, scheduler_suspend/1, @@ -249,6 +250,7 @@ bound_loop(NS, N, M, Sched) -> scheduler_bind(suite) -> [scheduler_bind_types, cpu_topology, + update_cpu_info, sct_cmd, sbt_cmd]. @@ -772,6 +774,137 @@ cpu_topology_cmdline_test(Config, Topology, Cmd) -> ?line stop_node(Node), ?line ok. +update_cpu_info(Config) when is_list(Config) -> + ?line OldOnline = erlang:system_info(schedulers_online), + ?line OldAff = get_affinity_mask(), + ?line ?t:format("START - Affinity mask: ~p - Schedulers online: ~p - Scheduler bindings: ~p~n", + [OldAff, OldOnline, erlang:system_info(scheduler_bindings)]), + ?line case {erlang:system_info(logical_processors_available), OldAff} of + {Avail, _} when Avail == unknown; OldAff == unknown -> + %% Nothing much to test; just a smoke test + case erlang:system_info(update_cpu_info) of + unchanged -> ?line ok; + changed -> ?line ok + end; + _ -> + try + ?line adjust_schedulers_online(), + case erlang:system_info(schedulers_online) of + 1 -> + %% Nothing much to test; just a smoke test + ?line ok; + Onln0 -> + %% unset least significant bit + ?line Aff = (OldAff band (OldAff - 1)), + ?line set_affinity_mask(Aff), + ?line Onln1 = Onln0 - 1, + ?line case adjust_schedulers_online() of + {Onln0, Onln1} -> + ?line Onln1 = erlang:system_info(schedulers_online), + ?line receive after 500 -> ok end, + ?line ?t:format("TEST - Affinity mask: ~p - Schedulers online: ~p - Scheduler bindings: ~p~n", + [Aff, Onln1, erlang:system_info(scheduler_bindings)]), + ?line unchanged = adjust_schedulers_online(), + ?line ok; + Fail -> + ?line ?t:fail(Fail) + end + end + after + set_affinity_mask(OldAff), + adjust_schedulers_online(), + erlang:system_flag(schedulers_online, OldOnline), + receive after 500 -> ok end, + ?t:format("END - Affinity mask: ~p - Schedulers online: ~p - Scheduler bindings: ~p~n", + [get_affinity_mask(), + erlang:system_info(schedulers_online), + erlang:system_info(scheduler_bindings)]) + end + 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} + end. + +read_affinity(Data) -> + Exp = "pid " ++ os:getpid() ++ "'s current affinity mask", + case string:tokens(Data, ":") of + [Exp, DirtyAffinityStr] -> + AffinityStr = string:strip(string:strip(DirtyAffinityStr, + both, $ ), + both, $\n), + case catch erlang:list_to_integer(AffinityStr, 16) of + Affinity when is_integer(Affinity) -> + Affinity; + _ -> + bad + end; + _ -> + bad + end. + +get_affinity_mask(Port, Status, Affinity) when Status == unknown; + Affinity == unknown -> + receive + {Port,{data, Data}} -> + get_affinity_mask(Port, Status, read_affinity(Data)); + {Port,{exit_status,S}} -> + get_affinity_mask(Port, S, Affinity) + end; +get_affinity_mask(Port, Status, bad) -> + unknown; +get_affinity_mask(Port, Status, Affinity) -> + Affinity. + +get_affinity_mask() -> + case ?t:os_type() of + {unix, linux} -> + case catch open_port({spawn, "taskset -p " ++ os:getpid()}, + [exit_status]) of + Port when is_port(Port) -> + get_affinity_mask(Port, unknown, unknown); + _ -> + unknown + end; + _ -> + unknown + end. + +set_affinity_mask(Port, unknown) -> + receive + {Port,{data, _}} -> + set_affinity_mask(Port, unknown); + {Port,{exit_status,Status}} -> + set_affinity_mask(Port, Status) + end; +set_affinity_mask(Port, Status) -> + receive + {Port,{data, _}} -> + set_affinity_mask(Port, unknown) + after 0 -> + Status + end. + +set_affinity_mask(Mask) -> + Cmd = lists:flatten(["taskset -p ", + io_lib:format("~.16b", [Mask]), + " ", + os:getpid()]), + case catch open_port({spawn, Cmd}, [exit_status]) of + Port when is_port(Port) -> + case set_affinity_mask(Port, unknown) of + 0 -> ok; + _ -> exit(failed_to_set_affinity) + end; + _ -> + exit(failed_to_set_affinity) + end. + sct_cmd(Config) when is_list(Config) -> ?line Topology = ?TOPOLOGY_A_TERM, ?line OldRelFlags = clear_erl_rel_flags(), |