Jake Burkholder wrote: > The system call stubs in libc are leaf functions; basically just a > trap instruction followed by a return. They do not touch the stack > at all, or change the stack pointer. One of the first few instructions > on entry to the kernel is a save, which rotates the register window > and logically saves the call-safe registers onto the user stack > (the outs become the ins, and the kernel gets new ins and locals, > with the old ones being saved to the user stack once a flush is > performed or they get spilled out). > > Here is a reference: http://www.sparc.com/standards/v9.ps.Z
Cool. Thanks for the reference. Though I think it's largely equivalent to the system call helper for threads context and stack switching in liblwp... 8-). -- Terry To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
