Commit Graph

16 Commits

Author SHA1 Message Date
Nathan Whitehorn
54c562081f Restructure the way the copyin/copyout segment is stored to prevent a
concurrency bug. Since all SLB/SR entries were invalidated during an
exception, a decrementer exception could cause the user segment to be
invalidated during a copyin()/copyout() without a thread switch that
would cause it to be restored from the PCB, potentially causing the
operation to continue on invalid memory. This is now handled by explicit
restoration of segment 12 from the PCB on 32-bit systems and a check in
the Data Segment Exception handler on 64-bit.

While here, cause copyin()/copyout() to check whether the requested
user segment is already installed, saving some pipeline flushes, and
fix the synchronization primitives around the mtsr and slbmte
instructions to prevent accessing stale segments.

MFC after:	2 weeks
2010-10-30 23:07:30 +00:00
Nathan Whitehorn
2639d62ec2 Handle vector assist traps without a kernel panic, by setting denormalized
values to zero. A correct solution would involve emulating vector
operations on denormalized values, but this has little effect on accuracy
and is much less complicated for now.

MFC after:	2 weeks
2010-10-05 18:08:07 +00:00
Nathan Whitehorn
95fa3335e1 Replace the SLB backing store splay tree used on 64-bit PowerPC AIM
hardware with a lockless sparse tree design. This marginally improves
the performance of PMAP and allows copyin()/copyout() to run without
acquiring locks when used on wired mappings.

Submitted by:	mdf
2010-09-16 00:22:25 +00:00
Nathan Whitehorn
c3e289e1ce MFppc64:
Kernel sources for 64-bit PowerPC, along with build-system changes to keep
32-bit kernels compiling (build system changes for 64-bit kernels are
coming later). Existing 32-bit PowerPC kernel configurations must be
updated after this change to specify their architecture.
2010-07-13 05:32:19 +00:00
Rafal Jaworowski
0a35b40f8d Make Book-E debug register state part of the PCB context.
Previously, DBCR0 flags were set "globally", but this leads to problems
because Book-E fine grained debug settings work only in conjuction with the
debug master enable bit in MSR: in scenarios when the DBCR0 was set with
intention to debug one process, but another one with MSR[DE] set got
scheduled, the latter would immediately cause debug exceptions to occur upon
execution of its own code instructions (and not the one intended for
debugging).

To avoid such problems and properly handle debugging context, DBCR0 state
should be managed individually per process.

Submitted by:	Grzegorz Bernacki gjb ! semihalf dot com
Reviewed by:	marcel
2009-02-27 12:08:24 +00:00
Nathan Whitehorn
1ac37bcb77 Add Altivec support for supported CPUs. This is derived from the FPU support
code, and also reducing the size of trapcode to fit inside a 32 byte handler
slot.

Reviewed by:	grehan
MFC after:	2 weeks
2009-02-20 17:48:40 +00:00
Rafal Jaworowski
786e4a1b04 Unify and generalize PowerPC headers, adjust AIM code accordingly.
Rework of this area is a pre-requirement for importing e500 support (and
other PowerPC core variations in the future). Mainly the following
headers are refactored so that we can cover for low-level differences between
various machines within PowerPC architecture:

  <machine/pcpu.h>
  <machine/pcb.h>
  <machine/kdb.h>
  <machine/hid.h>
  <machine/frame.h>

Areas which use the above are adjusted and cleaned up.

Credits for this rework go to marcel@

Approved by:	cognet (mentor)
MFp4:		e500
2008-03-02 17:05:57 +00:00
Marcel Moolenaar
f54721f6a6 Forward declare struct trapframe. 2006-07-26 17:05:11 +00:00
Peter Grehan
abdc8ff1bc Add prototype for KDB's makectx routine 2004-07-12 22:17:20 +00:00
Peter Grehan
f86c114f3d Add the USER_SR segment register to pcb state. Initialize correctly,
and save/restore during a context switch.

The USER_SR could be overwritten when the current thread was switched
out with a faulting copyin/copyout.

Approved by: Benno
2002-10-21 05:27:41 +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
Benno Rice
8b8aa9c1e6 To quote Peter:
The case in cpu_switch() where there isn't a higher priority thread
(choosethread() == curthread) uses r4 as the PCB context pointer. However, the
use of r4 after the label L2 is incorrect, since it was probably trashed by
the call to choosethread, and in any case was set up to curthread at the start
of the routine.

This condition will occur when an interrupt thread schedules a netisr, which
is a lower priority thread.

Another (probably unnecessary) difference is that I was paranoid about
register trashing, so I decided to save r2 and r13 as well.

Submitted by:	Peter Grehan <peterg@ptree32.com.au>
2002-06-29 09:39:44 +00:00
Benno Rice
eeaa897915 FPU support.
Obtained from:	NetBSD (portions)
2002-05-13 07:44:48 +00:00
Benno Rice
4eed0cf1be Make fork work, at least for kthreads. Switching still has some issues. 2002-02-28 03:24:07 +00:00
Mark Peek
422ec2ace1 Save WIP. Partial rewrite of cpu_switch() and savectx(). This makes it closer
to working but still needs some work to properly switch the full context
(such as saving the fpu registers, switch stacks, etc.).  Also, remove some
dead code that was mixed in.
2001-10-15 00:37:45 +00:00
Benno Rice
f9bac91b18 Bring in NetBSD code used in the PowerPC port.
Reviewed by:	obrien, dfr
Obtained from:	NetBSD
2001-06-10 02:39:37 +00:00