void prior_elem( sq_list list, ElemType *cur_elem, ElemType *prior_elem ){
Loc cur_elem_loc = locate_elem( list, cur_elem );
if( cur_elem_loc != list->length ){
get_elem( list, cur_elem_loc-1, prior_elem );
}
}
void next_elem( sq_list list, ElemType *cur_elem, ElemType *next_elem ){
Loc cur_elem_loc = locate_elem( list, cur_elem );
if( cur_elem_loc <= list->length - 1 ){
get_elem( list, cur_elem_loc+1, next_elem );
}
}
void update_process_group(struct process_group *pgroup)
{
struct process_iterator it;
struct process tmp_process;
struct process_filter filter;
struct timeval now;
gettimeofday(&now, NULL);
//time elapsed from previous sample (in ms)
long dt = timediff(&now, &pgroup->last_update) / 1000;
filter.pid = pgroup->target_pid;
filter.include_children = pgroup->include_children;
init_process_iterator(&it, &filter);
clear_list(pgroup->proclist);
init_list(pgroup->proclist, 4);
while (get_next_process(&it, &tmp_process) != -1)
{
// struct timeval t;
// gettimeofday(&t, NULL);
// printf("T=%ld.%ld PID=%d PPID=%d START=%d CPUTIME=%d\n", t.tv_sec, t.tv_usec, tmp_process.pid, tmp_process.ppid, tmp_process.starttime, tmp_process.cputime);
int hashkey = pid_hashfn(tmp_process.pid);
if (pgroup->proctable[hashkey] == NULL)
{
//empty bucket
pgroup->proctable[hashkey] = malloc(sizeof(struct list));
struct process *new_process = malloc(sizeof(struct process));
tmp_process.cpu_usage = -1;
memcpy(new_process, &tmp_process, sizeof(struct process));
init_list(pgroup->proctable[hashkey], 4);
add_elem(pgroup->proctable[hashkey], new_process);
add_elem(pgroup->proclist, new_process);
}
else
{
//existing bucket
struct process *p = (struct process*)locate_elem(pgroup->proctable[hashkey], &tmp_process);
if (p == NULL)
{
//process is new. add it
struct process *new_process = malloc(sizeof(struct process));
tmp_process.cpu_usage = -1;
memcpy(new_process, &tmp_process, sizeof(struct process));
add_elem(pgroup->proctable[hashkey], new_process);
add_elem(pgroup->proclist, new_process);
}
else
{
assert(tmp_process.pid == p->pid);
assert(tmp_process.ppid == p->ppid);
assert(tmp_process.starttime == p->starttime);
add_elem(pgroup->proclist, p);
if (dt < MIN_DT) continue;
//process exists. update CPU usage
double sample = 1.0 * (tmp_process.cputime - p->cputime) / dt;
if (p->cpu_usage == -1) {
//initialization
p->cpu_usage = sample;
}
else {
//usage adjustment
p->cpu_usage = (1.0-ALFA) * p->cpu_usage + ALFA * sample;
}
p->cputime = tmp_process.cputime;
}
}
}
close_process_iterator(&it);
if (dt < MIN_DT) return;
pgroup->last_update = now;
}
