remove code for dynamic offlining/onlining of CPUs on x86

The code has definitely been broken for SCHED_ULE, which is a default
scheduler.  It may have been broken for SCHED_4BSD in more subtle ways,
e.g. with manually configured CPU affinities and for interrupt devilery
purposes.
We still provide a way to disable individual CPUs or all hyperthreading
"twin" CPUs before SMP startup.  See the UPDATING entry for details.

Interaction between building CPU topology and disabling CPUs still
remains fuzzy: topology is first built using all availble CPUs and then
the disabled CPUs should be "subtracted" from it.  That doesn't work
well if the resulting topology becomes non-uniform.

This work is done in cooperation with Attilio Rao who in addition to
reviewing also provided parts of code.

PR:		kern/145385
Discussed with:	gcooper, ambrisko, mdf, sbruno
Reviewed by:	attilio
Tested by:	pho, pluknet
X-MFC after:	never

1 files changed, 0 insertions, 1 deletions

diff --git a/sys/i386/include/smp.h b/sys/i386/include/smp.h
index 33b2578..04d67c9 100644
--- a/sys/i386/include/smp.h
+++ b/sys/i386/include/smp.h
@@ -68,7 +68,6 @@ void	ipi_cpu(int cpu, u_int ipi);
 int	ipi_nmi_handler(void);
 void	ipi_selected(cpuset_t cpus, u_int ipi);
 u_int	mp_bootaddress(u_int);
-int	mp_grab_cpu_hlt(void);
 void	smp_cache_flush(void);
 void	smp_invlpg(vm_offset_t addr);
 void	smp_masked_invlpg(cpuset_t mask, vm_offset_t addr);