From bf0b86ea8e71d05331ef36c472f4dee646b22c38 Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Thu, 12 Apr 2018 11:54:47 +0200 Subject: erts: Add erts_debug:lc_graph/0 Run debug VM or config with --enable-lock-checking. Exercise VM and then run erts_debug:lc_graph(). to create a file "lc_graph." in current working directory. --- erts/emulator/beam/erl_lock_check.c | 111 +++++++++++++++++++++++++++++++++++- 1 file changed, 109 insertions(+), 2 deletions(-) (limited to 'erts/emulator/beam/erl_lock_check.c') 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 */ -- cgit v1.2.3