The HyperNews Linux KHG Discussion Pages

## answer

  Forum: The Linux Kernel Hackers' Guide
  Re: multitasking (Dennis J Perkins)
  Re: Answer (David Welch)
  Re: multitasking (Dennis J Perkins)
  Keywords: multitasking
  Date: Tue, 28 Apr 1998 12:59:48 GMT
  From: David Welch <welch@mcmail.com>

Not quite. If a process is executing a system call and interrupts are disabled then it will not be preempted (because the timer interrupt can't happen). Since interrupts are automatically disabled on entry to a system call and are only reenabled when the process will have to wait for a long time, most of time a process won't be preempted inside the kernel. However it can be preempted at any time when running in user mode.