CONFIG_X86_CMPXCHG on Intel 386 still needed?
gilles.chanteperdrix at laposte.net
Mon Oct 4 17:07:02 CEST 2004
Edelhard Becker wrote:
> we want to use RTAI on low-cost 386EX based boards. In 3.x, the
> availability of CONFIG_X86_CMPXCHG in the kernels .config is checked
> by RTAIs configure. From the comments in arch/i386/kernel/emu.c i'd
> expect that this check is not necessary when the kernel option
> CONFIG_X86_EMU486 is set. With the attached patch to RTAIs (3.1)
> configure at least it compiles fine. So is the check for "hardware-
> cmpxchg()" still needed?
a "grep cmpxchg" run in vesuvio sources, shows that it is used in the
implementation of the following components :
and in the following headers :
So, if you want to disable the check in configure.in, you should provide
a cli/sti based implementation of the atomic_cmpxchg macro.
More information about the Rtai