Re:why change: from proc to thread?

[kai ouyang]

Another problem:   There are not the structure 'bio' in FreeBSD 4.x, but exist in 5.0. If I want to transfer some pseudo-device code from 4.x to 5.0, what rules about old 'buf' structure to the 'bio' structure? what relation of the 'bio' and 'buf' in FreeBSD5.0? Thank you! Best Regards   Ouyang kai   On Mon, 27 May 2002, kai ouyang wrote: > Hi,everybody >   I found many v_operations, such as VOP_UNLOCK, VOP_OPEN....., there > all have a parameter(struct proc) in FreeBSD4.x, but, there all be > changed to thread in FreeBSD5.0. why? And what relation of the proc > and thread ? >   Thank you! > FreeBSD is plannig on supporting threads at a kernel level. To do this, the basic scheduling element becomes the thread instead of the process. For this reason, for example, locks must be held by threads instead of processes, and contexts are owned by threads instead of processes. This means that most functions will need a thread pointer instead of a process pointer. The "process" becomes basically an accounting abstraction and the holder of resources, where most of the kernel is more interested in the thread. Each process has at least one thread, possibly many. Each thread is associated with exactly one process. julian 从网站得到更多信息。MSN Explorer 免费下载：http://explorer.msn.com/lccn