diff --git a/innobase/btr/btr0sea.c b/innobase/btr/btr0sea.c index de3fe6e196e..5c5ed934a9b 100644 --- a/innobase/btr/btr0sea.c +++ b/innobase/btr/btr0sea.c @@ -508,6 +508,14 @@ btr_search_check_guess( /*===================*/ /* out: TRUE if success */ btr_cur_t* cursor, /* in: guessed cursor position */ + ibool can_only_compare_to_cursor_rec, + /* in: if we do not have a latch on the page + of cursor, but only a latch on + btr_search_latch, then ONLY the columns + of the record UNDER the cursor are + protected, not the next or previous record + in the chain: we cannot look at the next or + previous record to check our guess! */ dtuple_t* tuple, /* in: data tuple */ ulint mode, /* in: PAGE_CUR_L, PAGE_CUR_LE, PAGE_CUR_G, or PAGE_CUR_GE */ @@ -566,6 +574,13 @@ btr_search_check_guess( } } + if (can_only_compare_to_cursor_rec) { + /* Since we could not determine if our guess is right just by + looking at the record under the cursor, return FALSE */ + + return(FALSE); + } + match = 0; bytes = 0; @@ -670,6 +685,7 @@ btr_search_guess_on_hash( ulint fold; ulint tuple_n_fields; dulint tree_id; + ibool can_only_compare_to_cursor_rec = TRUE; #ifdef notdefined btr_cur_t cursor2; btr_pcur_t pcur; @@ -744,6 +760,8 @@ btr_search_guess_on_hash( goto failure; } + can_only_compare_to_cursor_rec = FALSE; + buf_page_dbg_add_level(page, SYNC_TREE_NODE_FROM_HASH); } @@ -775,7 +793,15 @@ btr_search_guess_on_hash( fold); */ } else { - success = btr_search_check_guess(cursor, tuple, mode, mtr); + /* If we only have the latch on btr_search_latch, not on the + page, it only protects the columns of the record the cursor + is positioned on. We cannot look at the next of the previous + record to determine if our guess for the cursor position is + right. */ + + success = btr_search_check_guess(cursor, + can_only_compare_to_cursor_rec, + tuple, mode, mtr); } if (!success) { diff --git a/innobase/include/btr0sea.h b/innobase/include/btr0sea.h index 14feca5d5c5..ee762a12221 100644 --- a/innobase/include/btr0sea.h +++ b/innobase/include/btr0sea.h @@ -234,10 +234,16 @@ struct btr_search_sys_struct{ extern btr_search_sys_t* btr_search_sys; /* The latch protecting the adaptive search system: this latch protects the -(1) positions of records on those pages where a hash index has been built. -NOTE: It does not protect values of non-ordering fields within a record from -being updated in-place! We can use fact (1) to perform unique searches to -indexes. */ +(1) hash index; +(2) columns of a record to which we have a pointer in the hash index; + +but does NOT protect: + +(3) next record offset field in a record; +(4) next or previous records on the same page. + +Bear in mind (3) and (4) when using the hash index. +*/ extern rw_lock_t* btr_search_latch_temp; diff --git a/sql/log_event.cc b/sql/log_event.cc index 1d27e48f14f..d2fcc83a98f 100644 --- a/sql/log_event.cc +++ b/sql/log_event.cc @@ -867,10 +867,11 @@ int Query_log_event::exec_event(struct st_relay_log_info* rli) if (db_ok(thd->db, replicate_do_db, replicate_ignore_db)) { - thd->query = (char*)query; thd->set_time((time_t)when); thd->current_tablenr = 0; + thd->query_length= q_len; VOID(pthread_mutex_lock(&LOCK_thread_count)); + thd->query = (char*)query; thd->query_id = query_id++; VOID(pthread_mutex_unlock(&LOCK_thread_count)); thd->query_error= 0; // clear error @@ -928,7 +929,9 @@ int Query_log_event::exec_event(struct st_relay_log_info* rli) else { // master could be inconsistent, abort and tell DBA to check/fix it + VOID(pthread_mutex_lock(&LOCK_thread_count)); thd->db = thd->query = 0; + VOID(pthread_mutex_unlock(&LOCK_thread_count)); thd->variables.convert_set = 0; close_thread_tables(thd); free_root(&thd->mem_root,0); @@ -936,7 +939,9 @@ int Query_log_event::exec_event(struct st_relay_log_info* rli) } } thd->db= 0; // prevent db from being freed + VOID(pthread_mutex_lock(&LOCK_thread_count)); thd->query= 0; // just to be sure + VOID(pthread_mutex_unlock(&LOCK_thread_count)); // assume no convert for next query unless set explictly thd->variables.convert_set = 0; close_thread_tables(thd); @@ -1513,7 +1518,8 @@ int Load_log_event::exec_event(NET* net, struct st_relay_log_info* rli, { init_sql_alloc(&thd->mem_root, 8192,0); thd->db = rewrite_db((char*)db); - thd->query = 0; + DBUG_ASSERT(thd->query == 0); + thd->query = 0; // Should not be needed thd->query_error = 0; if (db_ok(thd->db, replicate_do_db, replicate_ignore_db)) diff --git a/sql/slave.cc b/sql/slave.cc index 271fe8bc2d6..97961eb00f8 100644 --- a/sql/slave.cc +++ b/sql/slave.cc @@ -1011,6 +1011,7 @@ static int create_table_from_dump(THD* thd, NET* net, const char* db, const char* table_name) { ulong packet_len = my_net_read(net); // read create table statement + char *query; Vio* save_vio; HA_CHECK_OPT check_opt; TABLE_LIST tables; @@ -1030,15 +1031,23 @@ static int create_table_from_dump(THD* thd, NET* net, const char* db, return 1; } thd->command = COM_TABLE_DUMP; - thd->query = sql_alloc(packet_len + 1); - if (!thd->query) + /* Note that we should not set thd->query until the area is initalized */ + if (!(query = sql_alloc(packet_len + 1))) { sql_print_error("create_table_from_dump: out of memory"); net_printf(thd, ER_GET_ERRNO, "Out of memory"); return 1; } - memcpy(thd->query, net->read_pos, packet_len); - thd->query[packet_len] = 0; + memcpy(query, net->read_pos, packet_len); + query[packet_len]= 0; + thd->query_length= packet_len; + /* + We make the following lock in an attempt to ensure that the compiler will + not rearrange the code so that thd->query is set too soon + */ + VOID(pthread_mutex_lock(&LOCK_thread_count)); + thd->query= query; + VOID(pthread_mutex_unlock(&LOCK_thread_count)); thd->current_tablenr = 0; thd->query_error = 0; thd->net.no_send_ok = 1; @@ -2272,7 +2281,9 @@ err: // print the current replication position sql_print_error("Slave I/O thread exiting, read up to log '%s', position %s", IO_RPL_LOG_NAME, llstr(mi->master_log_pos,llbuff)); + VOID(pthread_mutex_lock(&LOCK_thread_count)); thd->query = thd->db = 0; // extra safety + VOID(pthread_mutex_unlock(&LOCK_thread_count)); if (mysql) { mc_mysql_close(mysql); @@ -2407,7 +2418,9 @@ the slave SQL thread with \"SLAVE START\". We stopped at log \ RPL_LOG_NAME, llstr(rli->master_log_pos,llbuff)); err: + VOID(pthread_mutex_lock(&LOCK_thread_count)); thd->query = thd->db = 0; // extra safety + VOID(pthread_mutex_unlock(&LOCK_thread_count)); thd->proc_info = "Waiting for slave mutex on exit"; pthread_mutex_lock(&rli->run_lock); DBUG_ASSERT(rli->slave_running == 1); // tracking buffer overrun diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index a09b3e9cad4..6719c9021a6 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -949,7 +949,7 @@ int mysql_table_dump(THD* thd, char* db, char* tbl_name, int fd) goto err; } net_flush(&thd->net); - if ((error = table->file->dump(thd,fd))) + if ((error= table->file->dump(thd,fd))) my_error(ER_GET_ERRNO, MYF(0)); err: @@ -1054,7 +1054,6 @@ bool dispatch_command(enum enum_server_command command, THD *thd, tbl_name[tbl_len] = 0; if (mysql_table_dump(thd, db, tbl_name, -1)) send_error(thd); // dump to NET - break; } case COM_CHANGE_USER: