July 3, 2007 PREEMPT 9

### NAME

preempt, yield - general preempt and yield functions

### SYNOPSIS

```void` preempt(```void`)
```void` yield(```void`)

### DESCRIPTION

The preempt(``) function puts the current LWP back on the system run queue and performs an involuntary context switch. The yield(``) function is mostly same as preempt(``), except that it performs a voluntary context switch.

These functions drop the kernel lock before switching and re-acquire it before returning.