chpl_bool chpl_mem_descTrack(chpl_mem_descInt_t mdi) {
//
// For the runtime-defined descriptor types, for now we either track
// the ones the static definition in the table says to, or we track
// them all. In the future we can imagine wanting to be able to
// turn them on and off individually, but we can wait for a use case
// before designing that capability.
//
if (mdi < CHPL_RT_MD_NUM) {
static chpl_bool track_all_mds;
static volatile chpl_bool track_all_mds_set = false;
//
// Init is parallel-safe because all stores are of the same values.
//
if (!track_all_mds_set) {
track_all_mds = chpl_get_rt_env_bool("MEMTRACK_ALL_MDS", false);
track_all_mds_set = true;
}
return track_all_mds || rt_md[mdi].track;
}
return true;
}
static void chpl_stack_unwind(void){
// This is just a prototype using libunwind
unw_cursor_t cursor;
unw_context_t uc;
unw_word_t wordValue;
char buffer[128];
unsigned int line;
#ifdef __linux__
unw_proc_info_t info;
// Get the exec path and name for the precise line printing
char process_name[128];
line = readlink("/proc/self/exe", process_name, sizeof(process_name));
// It unlikely to happen but this means that the process name is too big
// for our buffer. In this case, we truncate the name
if(line == sizeof(process_name))
line = sizeof(process_name)-1;
process_name[line] = '\0';
#endif
// Check if we need to print the stack trace (default = yes)
if(! chpl_get_rt_env_bool("UNWIND", true)) {
return;
}
line = 0;
unw_getcontext(&uc);
unw_init_local(&cursor, &uc);
if(chpl_sizeSymTable > 0)
fprintf(stderr,"Stacktrace\n\n");
// This loop does the effective stack unwind, see libunwind documentation
while (unw_step(&cursor) > 0) {
unw_get_proc_name(&cursor, buffer, sizeof(buffer), &wordValue);
// Since this stack trace is printed out a program exit, we do not believe
// it is performance sensitive. Additionally, this initial implementation
// favors simplicity over performance.
//
// If it becomes necessary to improve performance, this code could use be
// faster using one of these two strategies:
// 1) Use a hashtable or map to find entries in chpl_funSymTable, or
// 2) Emit chpl_funSymTable in sorted order and use binary search on it
for(int t = 0; t < chpl_sizeSymTable; t+=2 ){
if (!strcmp(chpl_funSymTable[t], buffer)){
#ifdef __linux__
// Maybe we can get a more precise line number
unw_get_proc_info(&cursor, &info);
line = chpl_unwind_getLineNum(process_name,
(void *)(info.start_ip + wordValue));
// We wasn't able to obtain the line number, let's use the procedure
// line number
if(line == 0)
line = chpl_filenumSymTable[t+1];
#else
line = chpl_filenumSymTable[t+1];
#endif
fprintf(stderr,"%s() at %s:%d\n",
chpl_funSymTable[t+1],
chpl_lookupFilename(chpl_filenumSymTable[t]),
line);
break;
}
}
}
}