DragonFly users List (threaded) for 2007-01
Re: Request for swapcontext and getcontext to be ported to our libc
So is the current context code going into cvs HEAD or whats happening?
Simon 'corecode' Schubert wrote:
Matthew Dillon wrote:
The answer is: yes, it is possible. There is no reason why the
signal mask (and signal pending bitmap) couldn't be stored in user
memory, allowing the userland threading system to swap out the mask
without entering the kernel.
I absolutely agree. I am thinking of a special page mapped in kernel
and userspace memory, where things like signal mask and pending (per
thread) are located, and maybe also a timecounter, pid, etc.
So I think there is a very good argument for making the current
implementation do these calls in libc and not as system calls, and
initially have libc just get the signal mask with a system call,
at some later date add the feature sthat allow the userland context
routines to run fully without having to make any system calls at
If Matt Emmerton finds the time to implement it, I am all for it.
Having these functions as syscalls seems wrong in my eyes.