do_times.c

Minix3.11的源码。[MINIX 3是一个为高可靠性应用而设计的自由且简洁的类UNIX系统。]

/* The kernel call implemented in this file:
 *   m_type:	SYS_TIMES
 *
 * The parameters for this kernel call are:
 *    m4_l1:	T_PROC_NR		(get info for this process)	
 *    m4_l1:	T_USER_TIME		(return values ...)	
 *    m4_l2:	T_SYSTEM_TIME	
 *    m4_l5:	T_BOOT_TICKS	
 */

#include "../system.h"

#if USE_TIMES

/*===========================================================================*
 *				do_times				     *
 *===========================================================================*/
PUBLIC int do_times(m_ptr)
register message *m_ptr;	/* pointer to request message */
{
/* Handle sys_times().  Retrieve the accounting information. */
  register struct proc *rp;
  int proc_nr;

  /* Insert the times needed by the SYS_TIMES kernel call in the message. 
   * The clock's interrupt handler may run to update the user or system time
   * while in this code, but that cannot do any harm.
   */
  proc_nr = (m_ptr->T_PROC_NR == SELF) ? m_ptr->m_source : m_ptr->T_PROC_NR;
  if (isokprocn(proc_nr)) {
      rp = proc_addr(m_ptr->T_PROC_NR);
      m_ptr->T_USER_TIME   = rp->p_user_time;
      m_ptr->T_SYSTEM_TIME = rp->p_sys_time;
  }
  m_ptr->T_BOOT_TICKS = get_uptime();  
  return(OK);
}

#endif /* USE_TIMES */