diff options
| -rw-r--r-- | erts/emulator/beam/erl_bif_info.c | 9 | ||||
| -rw-r--r-- | erts/emulator/beam/erl_lock_check.c | 111 | ||||
| -rw-r--r-- | erts/emulator/beam/erl_lock_check.h | 2 | ||||
| -rw-r--r-- | lib/kernel/src/erts_debug.erl | 90 |
4 files changed, 209 insertions, 3 deletions
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c index bdca93428e..874ac0f9e6 100644 --- a/erts/emulator/beam/erl_bif_info.c +++ b/erts/emulator/beam/erl_bif_info.c @@ -3928,6 +3928,15 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1) BIF_RET(am_false); #endif } + else if (ERTS_IS_ATOM_STR("lc_graph", BIF_ARG_1)) { +#ifdef ERTS_ENABLE_LOCK_CHECK + Eterm res = erts_lc_dump_graph(); + BIF_RET(res); +#else + BIF_RET(am_notsup); +#endif + } + } else if (is_tuple(BIF_ARG_1)) { Eterm* tp = tuple_val(BIF_ARG_1); diff --git a/erts/emulator/beam/erl_lock_check.c b/erts/emulator/beam/erl_lock_check.c index 5d33de9e88..53edf6abc1 100644 --- a/erts/emulator/beam/erl_lock_check.c +++ b/erts/emulator/beam/erl_lock_check.c @@ -41,6 +41,7 @@ #include "erl_lock_check.h" #include "erl_term.h" #include "erl_threads.h" +#include "erl_atom_table.h" typedef struct { char *name; @@ -75,6 +76,7 @@ static erts_lc_lock_order_t erts_lock_order[] = { * if only one lock use * the lock name)" */ + { "NO LOCK", NULL }, { "driver_lock", "driver_name" }, { "port_lock", "port_id" }, { "port_data_lock", "address" }, @@ -196,6 +198,19 @@ typedef struct { lc_locked_lock_t *last; } lc_locked_lock_list_t; +typedef struct { + /* + * m[X][Y] & 1 if we locked X directly after Y was locked. + * m[X][Y] & 2 if we locked X indirectly after Y was locked. + * m[X][0] = 1 if we locked X when nothing else was locked. + * m[0][] is unused as it would represent locking "NO LOCK" + */ + char m[ERTS_LOCK_ORDER_SIZE][ERTS_LOCK_ORDER_SIZE]; + +} lc_matrix_t; + +static lc_matrix_t tot_lc_matrix; + typedef struct lc_thread_t_ lc_thread_t; struct lc_thread_t_ { char *thread_name; @@ -205,6 +220,7 @@ struct lc_thread_t_ { lc_thread_t *prev; lc_locked_lock_list_t locked; lc_locked_lock_list_t required; + lc_matrix_t matrix; }; typedef union lc_free_block_t_ lc_free_block_t; @@ -322,6 +338,7 @@ create_thread_data(char *thread_name) thr->locked.first = NULL; thr->locked.last = NULL; thr->prev = NULL; + sys_memzero(&thr->matrix, sizeof(thr->matrix)); lc_lock(); thr->next = lc_threads; @@ -333,6 +350,8 @@ create_thread_data(char *thread_name) return thr; } +static void collect_matrix(lc_matrix_t*); + static void destroy_locked_locks(lc_thread_t *thr) { @@ -352,6 +371,9 @@ destroy_locked_locks(lc_thread_t *thr) } if (thr->next) thr->next->prev = thr->prev; + + collect_matrix(&thr->matrix); + lc_unlock(); free((void *) thr); @@ -394,7 +416,7 @@ static void raw_print_lock(char *prefix, Sint16 id, Wterm extra, erts_lock_flags_t flags, char* file, unsigned int line, char *suffix) { - char *lname = (0 <= id && id < ERTS_LOCK_ORDER_SIZE + char *lname = (1 <= id && id < ERTS_LOCK_ORDER_SIZE ? erts_lock_order[id].name : "unknown"); erts_fprintf(stderr,"%s'%s:",prefix,lname); @@ -1144,12 +1166,25 @@ void erts_lc_lock_flg_x(erts_lc_lock_t *lck, erts_lock_options_t options, if (!thr->locked.last) { ASSERT(!thr->locked.first); thr->locked.last = thr->locked.first = new_ll; + ASSERT(0 < lck->id && lck->id < ERTS_LOCK_ORDER_SIZE); + thr->matrix.m[lck->id][0] = 1; } else if (thr->locked.last->id < lck->id || (thr->locked.last->id == lck->id && thr->locked.last->extra < lck->extra)) { - if (LOCK_IS_TYPE_ORDER_VIOLATION(lck->flags, thr->locked.last->flags)) + lc_locked_lock_t* ll; + if (LOCK_IS_TYPE_ORDER_VIOLATION(lck->flags, thr->locked.last->flags)) { type_order_violation("locking ", thr, lck); + } + + ASSERT(0 < lck->id && lck->id < ERTS_LOCK_ORDER_SIZE); + ll = thr->locked.last; + thr->matrix.m[lck->id][ll->id] |= 1; + for (ll = ll->prev; ll; ll = ll->prev) { + ASSERT(0 < ll->id && ll->id < ERTS_LOCK_ORDER_SIZE); + thr->matrix.m[lck->id][ll->id] |= 2; + } + new_ll->prev = thr->locked.last; thr->locked.last->next = new_ll; thr->locked.last = new_ll; @@ -1342,4 +1377,76 @@ erts_lc_pll(void) print_curr_locks(get_my_locked_locks()); } +static void collect_matrix(lc_matrix_t* matrix) +{ + int i, j; + for (i = 1; i < ERTS_LOCK_ORDER_SIZE; i++) { + for (j = 0; j <= i; j++) { + tot_lc_matrix.m[i][j] |= matrix->m[i][j]; + } +#ifdef DEBUG + for ( ; j < ERTS_LOCK_ORDER_SIZE; j++) { + ASSERT(matrix->m[i][j] == 0); + } +#endif + } +} + +Eterm +erts_lc_dump_graph(void) +{ + const char* basename = "lc_graph."; + char filename[40]; + lc_matrix_t* tot = &tot_lc_matrix; + lc_thread_t* thr; + int i, j, name_max = 0; + FILE* ff; + + lc_lock(); + for (thr = lc_threads; thr; thr = thr->next) { + collect_matrix(&thr->matrix); + } + lc_unlock(); + + sys_strcpy(filename, basename); + sys_get_pid(filename + strlen(basename), + sizeof(filename) - strlen(basename)); + ff = fopen(filename, "w"); + if (!ff) + return am_error; + + for (i = 1; i < ERTS_LOCK_ORDER_SIZE; i++) { + int len = strlen(erts_lock_order[i].name); + if (name_max < len) + name_max = len; + } + fputs("%This file was generated by erts_debug:lc_graph()\n\n", ff); + fputs("%{ThisLockName, ThisLockId, LockedDirectlyBeforeThis, LockedIndirectlyBeforeThis}\n", ff); + fprintf(ff, "[{%*s, %2d}", name_max, "\"NO LOCK\"", 0); + for (i = 1; i < ERTS_LOCK_ORDER_SIZE; i++) { + char* delim = ""; + fprintf(ff, ",\n {%*s, %2d, [", name_max, erts_lock_order[i].name, i); + for (j = 0; j < ERTS_LOCK_ORDER_SIZE; j++) { + if (tot->m[i][j] & 1) { + fprintf(ff, "%s%d", delim, j); + delim = ","; + } + } + fprintf(ff, "], ["); + delim = ""; + for (j = 0; j < ERTS_LOCK_ORDER_SIZE; j++) { + if (tot->m[i][j] == 2) { + fprintf(ff, "%s%d", delim, j); + delim = ","; + } + } + fputs("]}", ff); + } + fputs("].", ff); + fclose(ff); + erts_fprintf(stderr, "Created file '%s' in current working directory\n", + filename); + return am_ok; +} + #endif /* #ifdef ERTS_ENABLE_LOCK_CHECK */ diff --git a/erts/emulator/beam/erl_lock_check.h b/erts/emulator/beam/erl_lock_check.h index 5c2c38e8f2..138bc810bd 100644 --- a/erts/emulator/beam/erl_lock_check.h +++ b/erts/emulator/beam/erl_lock_check.h @@ -94,6 +94,8 @@ void erts_lc_unrequire_lock(erts_lc_lock_t *lck); int erts_lc_is_emu_thr(void); +Eterm erts_lc_dump_graph(void); + #define ERTS_LC_ASSERT(A) \ ((void) (((A) || ERTS_SOMEONE_IS_CRASH_DUMPING) ? 1 : erts_lc_assert_failed(__FILE__, __LINE__, #A))) #else /* #ifdef ERTS_ENABLE_LOCK_CHECK */ diff --git a/lib/kernel/src/erts_debug.erl b/lib/kernel/src/erts_debug.erl index 6f248626ca..1270de4144 100644 --- a/lib/kernel/src/erts_debug.erl +++ b/lib/kernel/src/erts_debug.erl @@ -35,7 +35,8 @@ flat_size/1, get_internal_state/1, instructions/0, map_info/1, same/2, set_internal_state/2, size_shared/1, copy_shared/1, dirty_cpu/2, dirty_io/2, dirty/3, - lcnt_control/1, lcnt_control/2, lcnt_collect/0, lcnt_clear/0]). + lcnt_control/1, lcnt_control/2, lcnt_collect/0, lcnt_clear/0, + lc_graph/0, lc_graph_to_dot/2, lc_graph_merge/2]). -spec breakpoint(MFA, Flag) -> non_neg_integer() when MFA :: {Module :: module(), @@ -407,3 +408,90 @@ cont_dis(_, {_,_,_}, _) -> ok. map_info(_) -> erlang:nif_error(undef). + +%% Create file "lc_graph.<pid>" with all actual lock dependencies +%% recorded so far by the VM. +%% Needs debug VM or --enable-lock-checking config, returns 'notsup' otherwise. +lc_graph() -> + erts_debug:set_internal_state(available_internal_state, true), + erts_debug:get_internal_state(lc_graph). + +%% Convert "lc_graph.<pid>" file to https://www.graphviz.org dot format. +lc_graph_to_dot(OutFile, InFile) -> + {ok, [LL0]} = file:consult(InFile), + + [{"NO LOCK",0} | LL] = LL0, + Map = maps:from_list([{Id, Name} || {Name, Id, _, _} <- LL]), + + case file:open(OutFile, [exclusive]) of + {ok, Out} -> + ok = file:write(Out, "digraph G {\n"), + + [dot_print_lock(Out, Lck, Map) || Lck <- LL], + + ok = file:write(Out, "}\n"), + ok = file:close(Out); + + {error,eexist} -> + {"File already exists", OutFile} + end. + +dot_print_lock(Out, {_Name, Id, Lst, _}, Map) -> + [dot_print_edge(Out, From, Id, Map) || From <- Lst], + ok. + +dot_print_edge(_, 0, _, _) -> + ignore; % "NO LOCK" +dot_print_edge(Out, From, To, Map) -> + io:format(Out, "~p -> ~p;\n", [maps:get(From,Map), maps:get(To,Map)]). + + +%% Merge several "lc_graph" files into one file. +lc_graph_merge(OutFile, InFiles) -> + LLs = lists:map(fun(InFile) -> + {ok, [LL]} = file:consult(InFile), + LL + end, + InFiles), + + Res = lists:foldl(fun(A, B) -> lcg_merge(A, B) end, + hd(LLs), + tl(LLs)), + case file:open(OutFile, [exclusive]) of + {ok, Out} -> + try + lcg_print(Out, Res) + after + file:close(Out) + end, + ok; + {error, eexist} -> + {"File already exists", OutFile} + end. + +lcg_merge(A, B) -> + lists:zipwith(fun(LA, LB) -> lcg_merge_locks(LA, LB) end, + A, B). + +lcg_merge_locks(L, L) -> + L; +lcg_merge_locks({Name, Id, DA, IA}, {Name, Id, DB, IB}) -> + Direct = lists:umerge(DA, DB), + Indirect = lists:umerge(IA, IB), + {Name, Id, Direct, Indirect -- Direct}. + + +lcg_print(Out, LL) -> + io:format(Out, "[", []), + lcg_print_locks(Out, LL), + io:format(Out, "].\n", []), + ok. + +lcg_print_locks(Out, [{_,_}=NoLock | Rest]) -> + io:format(Out, "~p,\n", [NoLock]), + lcg_print_locks(Out, Rest); +lcg_print_locks(Out, [LastLock]) -> + io:format(Out, "~w", [LastLock]); +lcg_print_locks(Out, [Lock | Rest]) -> + io:format(Out, "~w,\n", [Lock]), + lcg_print_locks(Out, Rest). |