I am trying to get process start time in kernel module.
I get the proc struct pointer, and from the proc I take field p_mstart ()
typedef struct proc {
.....
/*
* Microstate accounting, resource usage, and real-time profiling
*/
hrtime_t p_mstart; /* hi-res process start time */
this return me the number: 1976026375725303
struct proc* iterated_process_ptr = curproc
LOG("***KERNEL***: PID=%d, StartTime=%lld",iterated_process_ptr->p_pidp->pid_id, iterated_process_ptr->p_mstart);
What is this number ? In the documentation solaris write:
The gethrtime() function returns the current high-resolution real time. Time is expressed as nanoseconds since some arbitrary time in the past.
And in the book Solaris Internals they write:
Within the process, the operating system maintains a high-resolution teimstamp that marks process start and terminate times, A p_mstart field, the process start time, is set in the kernel fork() code when the process is created.... it return 64-bit value expressed in nanosecond
The number 1976026375725303 does not make sense at all.
If i divide by 1,000,000,000 and then by 3600 in order to get hours, i get 528 hours, 22 days, but my uptime is 5 days..
Based on answer received at google group: comp.unix.solaris.
Instead of going to proc -> p_mstart
I need to take
iterated_process_ptr ->p_user.u_start
This bring me the same struct (timestruc_t) as userspace
typedef struct psinfo {
psinfo ->pr_start; /* process start time, from the epoch */