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
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
passing a pointer to an opaque clockframe structure and requiring the
MD code to supply CLKF_FOO() macros to extract needed values out of the
opaque structure, just pass the needed values directly. In practice this
means passing the pair (usermode, pc) to hardclock() and profclock() and
passing the boolean (usermode) to hardclock_cpu() and hardclock_process().
Other details:
- Axe clockframe and CLKF_FOO() macros on all architectures. Basically,
all the archs were taking a trapframe and converting it into a clockframe
one way or another. Now they can just extract the PC and usermode values
directly out of the trapframe and pass it to fooclock().
- Renamed hardclock_process() to hardclock_cpu() as the latter is more
accurate.
- On Alpha, we now run profclock() at hz (profhz == hz) rather than at
the slower stathz.
- On Alpha, for the TurboLaser machines that don't have an 8254
timecounter, call hardclock() directly. This removes an extra
conditional check from every clock interrupt on Alpha on the BSP.
There is probably room for even further pruning here by changing Alpha
to use the simplified timecounter we use on x86 with the lapic timer
since we don't get interrupts from the 8254 on Alpha anyway.
- On x86, clkintr() shouldn't ever be called now unless using_lapic_timer
is false, so add a KASSERT() to that affect and remove a condition
to slightly optimize the non-lapic case.
- Change prototypeof arm_handler_execute() so that it's first arg is a
trapframe pointer rather than a void pointer for clarity.
- Use KCOUNT macro in profclock() to lookup the kernel profiling bucket.
Tested on: alpha, amd64, arm, i386, ia64, sparc64
Reviewed by: bde (mostly)
and saved link register as per the ABI call sequence. Update code
that uses this (fork_trampoline etc) to use the correct genassym'd
offsets.
This fixes the 'invalid LR' message when backtracing kernel
threads in DDB.
Highlights include:
- New low-level trap code from NetBSD. The high level code still needs a lot
of work.
- Fixes for some pmap handling in thread switching.
- The kernel will now get to attempting to jump into init in user mode. There
are some pmap/trap issues which prevent it from actually getting there though.
Obtained from: NetBSD (parts)
