Request for swapcontext and getcontext to be ported to our libc

Simon 'corecode' Schubert corecode at fs.ei.tum.de
Fri Jan 12 17:51:59 PST 2007


Matt Emmerton wrote:
Simon wrote:
Matt Emmerton wrote:
I've toyed with it a bit, but there are some issues I'm not sure how to
solve (such as accessing curthread -- a kernel construct -- from
userland).
I would welcome discussion with the person who suggested it (corecode?).
In which way do you have to access curthread?  That's a kernel-only
entity, I don't think you have to access that in userland.  Besides, if we
take in the system call version, there is no need for a pure libc based
version anymore.
Point taken, and that's definitely the path we're going down at the moment.

However, I recall it being mentioned that the proliferation of syscalls is
unneccessary, so a libc implementation would keep the kernel lean.
Once we have introduced this syscall, we can't remove it anymore for binary compatibility.

 The
reason we need curthread is to get access to the frame construct, which is
neccessary to save the context.
when you are in userland, you have to build the frame yourself.

cheers
 simon
--
Serve - BSD     +++  RENT this banner advert  +++    ASCII Ribbon   /"\
Work - Mac      +++  space for low €€€ NOW!1  +++      Campaign     \ /
Party Enjoy Relax   |   http://dragonflybsd.org      Against  HTML   \
Dude 2c 2 the max   !   http://golden-apple.biz       Mail + News   / \
Attachment:
signature.asc
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pgp00007.pgp
Type: application/octet-stream
Size: 252 bytes
Desc: "Description: OpenPGP digital signature"
URL: <http://lists.dragonflybsd.org/pipermail/users/attachments/20070112/c5c0641f/attachment-0015.obj>


More information about the Users mailing list