Commit Graph

16 Commits

Author SHA1 Message Date
Marcel Moolenaar
344bbdbd54 As I said: the previous commit was untested... Remove an #endif which
should have ceased to exist when its corresponding #if was removed.
2004-08-16 19:05:08 +00:00
Marcel Moolenaar
97752b2cbd Catch up with the drive-by renaming of IA32 to COMPAT_IA32. It must
have been rush hour...

While here, move COMPAT_IA32 from opt_global.h to opt_compat.h like on
amd64. Consequently, it's unsafe to use the option in pcb.h. We now
unconditionally have the ia32 specific registers in the PCB.

This commit is untested.
2004-08-16 18:54:23 +00:00
Marcel Moolenaar
5a39cbaf69 Implement makectx(). The makectx() function is used by KDB to create
a PCB from a trapframe for purposes of unwinding the stack. The PCB
is used as the thread context and all but the thread that entered the
debugger has a valid PCB.
This function can also be used to create a context for the threads
running on the CPUs that have been stopped when the debugger got
entered. This however is not done at the time of this commit.
2004-07-10 19:56:00 +00:00
Marcel Moolenaar
e57196b3db Cleanup prototypes in cpu.h, including fswintrberr and any references
to it. Sort the remaining prototypes in cpu.h.

No functional change.
2003-08-12 03:51:53 +00:00
Marcel Moolenaar
f2c49dd248 Revamp of the syscall path, exception and context handling. The
prime objectives are:
o  Implement a syscall path based on the epc inststruction (see
   sys/ia64/ia64/syscall.s).
o  Revisit the places were we need to save and restore registers
   and define those contexts in terms of the register sets (see
   sys/ia64/include/_regset.h).

Secundairy objectives:
o  Remove the requirement to use contigmalloc for kernel stacks.
o  Better handling of the high FP registers for SMP systems.
o  Switch to the new cpu_switch() and cpu_throw() semantics.
o  Add a good unwinder to reconstruct contexts for the rare
   cases we need to (see sys/contrib/ia64/libuwx)

Many files are affected by this change. Functionally it boils
down to:
o  The EPC syscall doesn't preserve registers it does not need
   to preserve and places the arguments differently on the stack.
   This affects libc and truss.
o  The address of the kernel page directory (kptdir) had to
   be unstaticized for use by the nested TLB fault handler.
   The name has been changed to ia64_kptdir to avoid conflicts.
   The renaming affects libkvm.
o  The trapframe only contains the special registers and the
   scratch registers. For syscalls using the EPC syscall path
   no scratch registers are saved. This affects all places where
   the trapframe is accessed. Most notably the unaligned access
   handler, the signal delivery code and the debugger.
o  Context switching only partly saves the special registers
   and the preserved registers. This affects cpu_switch() and
   triggered the move to the new semantics, which additionally
   affects cpu_throw().
o  The high FP registers are either in the PCB or on some
   CPU. context switching for them is done lazily. This affects
   trap().
o  The mcontext has room for all registers, but not all of them
   have to be defined in all cases. This mostly affects signal
   delivery code now. The *context syscalls are as of yet still
   unimplemented.

Many details went into the removal of the requirement to use
contigmalloc for kernel stacks. The details are mostly CPU
specific and limited to exception_save() and exception_restore().
The few places where we create, destroy or switch stacks were
mostly simplified by not having to construct physical addresses
and additionally saving the virtual addresses for later use.

Besides more efficient context saving and restoring, which of
course yields a noticable speedup, this also fixes the dreaded
SMP bootup problem as a side-effect. The details of which are
still not fully understood.

This change includes all the necessary backward compatibility
code to have it handle older userland binaries that use the
break instruction for syscalls. Support for break-based syscalls
has been pessimized in favor of a clean implementation. Due to
the overall better performance of the kernel, this will still
be notived as an improvement if it's noticed at all.

Approved by: re@ (jhb)
2003-05-16 21:26:42 +00:00
Marcel Moolenaar
22d9ff4691 Rewrite cpu_switch(). The most notable change is the fact that we now
have f16-f31 as part of the context. The PCB has been reorganized to
better match how we save and restore the (preserved) registers. This
commit also moves the context restoriation to its own function (named
pcb_restore), as we did with pcb_save.

Only minimal effort has been put in writing optimal assembly. The
expectation is that there will be more rounds of changes.
2002-10-30 05:55:29 +00:00
Peter Wemm
af3f249f3a The a.out md_coredump stuff isn't referenced anywhere anymore, and
hasn't been filled in for ages..  Nuked.
2002-10-15 00:02:50 +00:00
Marcel Moolenaar
55f50d95f7 o Move prototypes for restorectx and savectx from cpu.h to pcb.h,
o  Remove Alpha specific contents of struct md_coredump.
2002-05-19 04:14:42 +00:00
Marcel Moolenaar
bb9c068e14 o Add ar.lc to the pcb.
o  Create pcb_save as the backend for savectx and cpu_switch.
o  While here, use explicit bundling for pcb_save and optimize
   for compactness (~87% density).

o  Not part of the commit is a backend pcb_restore. restorectx()
   still jumps halfway into cpu_switch().
2002-05-07 05:52:27 +00:00
Doug Rabson
02939fd82c Add fields for saving/restoring the IA-32 state. 2002-04-10 19:23:21 +00:00
Doug Rabson
a9521dec8b Add a field to hold the current pmap of a thread. 2002-03-14 19:19:49 +00:00
John Baldwin
2f01e2eaf2 Axe pcb_schednest as it is no longer used. 2001-02-22 17:09:50 +00:00
Doug Rabson
5596cfd09a * Fix exception handling so that it actually works. We can now handle
exceptions from both kernel and user mode.
* Fix context switching so that we can switch back to a proc which we
  switched away from (we were saving the state in the wrong place).
* Implement lazy switching of the high-fp state. This needs to be looked
  at again for SMP to cope with the case of a process migrating from one
  processor to another while it has the high-fp state.
* Make setregs() work properly. I still think this should be called
  cpu_exec() or something.
* Various other minor fixes.

With this lot, we can execve() /sbin/init and we get all the way up to its
first syscall. At that point, we stop because syscall handling is not done
yet.
2000-10-12 14:36:39 +00:00
Doug Rabson
8d9761debf Next round of fixes to the ia64 code. This includes simulated clock and
disk drivers along with a load of fixes to context switching, fork
handling and a load of other stuff I can't remember now. This takes us as
far as start_init() before it dies. I guess now I will have to finish off
the VM system and syscall handling :-).
2000-10-04 17:53:03 +00:00
Doug Rabson
431f3cb41d Next round of ia64 work, including fixes to context switching,
implementing cpu_fork(), copy*str(), bcopy(), copy{in,out}(). With these
changes, my test kernel reaches the mountroot prompt.
2000-09-30 17:48:44 +00:00
Doug Rabson
1ebcad5720 This is the first snapshot of the FreeBSD/ia64 kernel. This kernel will
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.
2000-09-29 13:46:07 +00:00