Hi,

 As of 5.11 kernel (pid,pid_start_time) is not unique /monotonic even
though the underlying counters are .
 I chose start_boottime because i wanted the counter to increase
during suspend as well.

1. Is there any case where task->start_boottime or
ktime_get_boottime_ns doesn't become monotonic i.e increasing ?

2.  If start_boottime is not monotonic which counter to use ?

3.  If i create a new field in task_struct , then i can use a
atomic_add_return(1,&v) to fill in the task->new_field. Will this also
work ?