Gareth Hughes wrote:
It is critically important for OpenGL drivers to have fast
(single-instruction) access to thread local variables. ...
While glibc's new thread library implementation has many benefits,
particularly to application programmers (with support for the new keyword
'__thread', and so on), it basically forces a function call per thread local
variable access for situations like the one I described above. ...
Comments, questions are welcome.
Hi Gareth,
I forwarded your note to the NPTL mailing list.
Roland McGrath replied, and suggests that you might want to
reread the TLS paper
(I think he's referring to http://people.redhat.com/drepper/nptl-design.pdf,
which appears to be offline at the moment); also look at the GCC
implementation of __thread, and note -ftls-model and __attribute__ ((tls_model)).
If that didn't make any sense, it's probably because I mangled Roland's words;
you might want to ask him what he meant.
- Dan
--
Dan Kegel
http://www.kegel.com
http://counter.li.org/cgi-bin/runscript/display-person.cgi?user=78045