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)
with the exception of indirect function calls, are assumed to be
intra load module and thus that GP will be the same. This avoids
saving, setting and restoring GP for each function call and
reduces the kernel with ~320KB. There's obviously a performance
benefit as well.
Note that since we generally don't know if calls will be intra or
inter load module when we're compiling kernel modules, -mconstant-gp
cannot be used for modules.
(PROFLEVEL) to kern.pre.mk so that it is easier to manage. Bumped config
version to match.
Moved the check for cputype being configured to a less bogus place in
mkmakefile.c.
It doesn't actually do it yet though. This adds a flag to config so
that we can exclude certain vendor files from this even when the rest
of the kernel has it on. make -DNO_WERROR would also bypass all of it.
new files: kern.pre.mk, which contains most of the definitions, and
kern.post.mk, which contains most of the rules.
I've tested this on i386 and pc98. I have had feedback on the sparc64
port, but no reports from anybody on alpha, ia64 or powerpc. I
appologize in advance if I've broken you.
Reviewed by: jake, jhb, arch@
booted from it when doing an installkernel.
Only change kern.bootfile from ${DESTDIR}${KODIR}/${KERNEL_KO}
to ${DESTDIR}${KODIR}.old/${KERNEL_KO}, and only when we're renaming
a booted ${DESTDIR}${KODIR}/${KERNEL_KO} kernel.
Small tweaks to kldxref may be necessary to avoid the surprising (but harm-
less) behaviour of 'kldload foo' loading foo.ko.debug instead of foo.ko if
it is present in the kernel directory.
Approved by: a week of silence on -arch
MFC after: 2 weeks
to locore to process the @fptr relocations in the dynamic executable.
* Don't initialise the timer until *after* we install the timecounter to
avoid a race between timecounter initialisation and hardclock.
* Tidy up bootinfo somewhat including adding sanity checks for when the
kernel is loaded without a recognisable bootinfo.
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible. <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.
The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).
The macros declare a strongly typed set. They return elements with the
type that you declare the set with, rather than a generic void *.
For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>). Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.
For a.out, we use the old linker_set struct.
NOTE: the item lists are no longer null terminated. This is why
the code impact is high in certain areas.
The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.
linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.
Reviewed by: eivind
We are way too inconsistent with our setting of the "schg" flag, and in
our default install, it doesn't really offer any additional security.
Reviewed by: arch@
that I removed in my last commit dealing with `make depend' bogons.
This commit has some races, but hopefully they are too short to matter.
Unfortuneatly, neither .newdep nor .olddep is removed by `make clean'.
Submitted by: bde
o Use objdump instead of gensetdefs(1) to build the linker sets.
o Allow overriding of nm and objdump in resp. genassym.sh and
gensetdefs.pl for non-native toolchains.
Reviewed by: arch
Perl improvements: Jos Backus <josb@cncdsl.com>, benno
{kernel,modules}-reinstall.debug rather than {kernel,modules}-reinstall.
Otherwise, the '.debug' portion of the target is lost, and you end up
reinstalling the non debug version instead of the debug version.
