Reimplement the lazy FP context switching:

o   Move all code into a single file for easier maintenance.
o   Use a single global lock to avoid having to handle either
    multiple locks or race conditions.
o   Make sure to disable the high FP registers after saving
    or dropping them.
o   use msleep() to wait for the other CPU to save the high
    FP registers.

This change fixes the high FP inconsistency panics.

A single global lock typically serializes too much, which may
be noticable when a lot of threads use the high FP registers,
but in that case it's probably better to switch the high FP
context synchronuously. Put differently: cpu_switch() should
switch the high FP registers if the incoming and outgoing
threads both use the high FP registers.

1 files changed, 2 insertions, 0 deletions

diff --git a/sys/ia64/include/md_var.h b/sys/ia64/include/md_var.h
index adc4725..6ee4cb4 100644
--- a/sys/ia64/include/md_var.h
+++ b/sys/ia64/include/md_var.h
@@ -86,7 +86,9 @@ int	ia64_emulate(struct trapframe *, struct thread *);
 int	ia64_flush_dirty(struct thread *, struct _special *);
 uint64_t ia64_get_hcdp(void);
 int	ia64_highfp_drop(struct thread *);
+int	ia64_highfp_enable(struct thread *, struct trapframe *);
 int	ia64_highfp_save(struct thread *);
+int	ia64_highfp_save_ipi(void);
 struct ia64_init_return ia64_init(void);
 void	ia64_probe_sapics(void);
 void	ia64_sync_icache(vm_offset_t, vm_size_t);