There are various options documented in i386/conf/LINT, there is more to
come over the next few days.
The kernel should run pretty much "as before" without the options to
activate SMP mode.
There are a handful of known "loose ends" that need to be fixed, but
have been put off since the SMP kernel is in a moderately good condition
at the moment.
This commit is the result of the tinkering and testing over the last 14
months by many people. A special thanks to Steve Passe for implementing
the APIC code!
for syscalls, so one frame was lost in backtraces from syscalls.
This is handled better in the kernel by using a different mcount
entry point for profiling before the frame pointer is set up.
Expand RCSID().
Use .p2align instead of the ambiguous .align.
Added idempotency ifdef.
Removed unused macros ALTENTRY(), ALTASENTRY(), ASENTRY(), _MID_ENTRY.
Cleaned up formatting.
Reviewed by: jdp reviewed an old version
Obtained from: parts from NetBSD
have successfully built, booted, and run a number of different ELF
kernel configurations, including GENERIC. LINT also builds and
links cleanly, though I have not tried to boot it.
The impact on developers is virtually nil, except for two things.
All linker sets that might possibly be present in the kernel must be
listed in "sys/i386/i386/setdefs.h". And all C symbols that are
also referenced from assembly language code must be listed in
"sys/i386/include/asnames.h". It so happens that failure to do
these things will have no impact on the a.out kernel. But it will
break the build of the ELF kernel.
The ELF bootloader works, but it is not ready to commit quite yet.
were always in a tss; that tss just changed from the one in the
pcb to common_tss (who knows where it was when there was no curpcb?).
Not using the pcb also fixed the problem that there is no pcb in
idle(), so we now always get useful register values.
switching to a child for the first time was being counted twice. I think
this only affected unimportant statistics.
Simplified arg handling in fork_trampoline(). splz() doesn't actually
smash the registers of interest.
allow large systems to boot successfully with bounce buffers compiled
in. We are now limiting bounce space to 512K. The 8MB allocated for
a 512MB system is very bogus -- and that is now fixed.
the pv entries. This problem has become obvious due to the increase
in the size of the pv entries. We need to create a more intelligent
policy for pv entry management eventually.
Submitted by: David Greenman <dg@freebsd.org>
fork. (On my machine, fork is about 240usecs, vfork is 78usecs.)
Implement rfork(!RFPROC !RFMEM), which allows a thread to divorce its memory
from the other threads of a group.
Implement rfork(!RFPROC RFCFDG), which closes all file descriptors, eliminating
possible existing shares with other threads/processes.
Implement rfork(!RFPROC RFFDG), which divorces the file descriptors for a
thread from the rest of the group.
Fix the case where a thread does an exec. It is almost nonsense for a thread
to modify the other threads address space by an exec, so we
now automatically divorce the address space before modifying it.
nothing else will lower it until either much later, or never(?) for
kernel processes.
This basically re-fixes what Bruce fixed in rev 1.29 of kern_fork.c,
which was broken again now the child does not execute back up the fork()
calling tree.
Rename the PT* index KSTK* #defines to UMAX*, since we don't have a kernel
stack there any more..
These are used to calculate VM_MAXUSER_ADDRESS and USRSTACK, and really
do not want to be changed with UPAGES since BSD/OS 2.x binary compatability
depends on it.
space. (!)
Have each process use the kernel stack and pcb in the kvm space. Since
the stacks are at a different address, we cannot copy the stack at fork()
and allow the child to return up through the function call tree to return
to user mode - create a new execution context and have the new process
begin executing from cpu_switch() and go to user mode directly.
In theory this should speed up fork a bit.
Context switch the tss_esp0 pointer in the common tss. This is a lot
simpler since than swithching the gdt[GPROC0_SEL].sd.sd_base pointer
to each process's tss since the esp0 pointer is a 32 bit pointer, and the
sd_base setting is split into three different bit sections at non-aligned
boundaries and requires a lot of twiddling to reset.
The 8K of memory at the top of the process space is now empty, and unmapped
(and unmappable, it's higher than VM_MAXUSER_ADDRESS).
Simplity the pmap code to manage process contexts, we no longer have to
double map the UPAGES, this simplifies and should measuably speed up fork().
The following parts came from John Dyson:
Set PG_G on the UPAGES that are now in kernel context, and invalidate
them when swapping them out.
Move the upages object (upobj) from the vmspace to the proc structure.
Now that the UPAGES (pcb and kernel stack) are out of user space, make
rfork(..RFMEM..) do what was intended by sharing the vmspace
entirely via reference counting rather than simply inheriting the mappings.
convenient and makes life difficult for my next commit. We still need
an i386tss to point to for the tss slot in the gdt, so we use a common
tss shared between all processes.
Note that this is going to break debugging until this series of commits
is finished. core dumps will change again too. :-( we really need
a more modern core dump format that doesn't depend on the pcb/upages.
This change makes VM86 mode harder, but the following commits will remove
a lot of constraints for the VM86 system, including the possibility of
extending the pcb for an IO port map etc.
Obtained from: bde
by Alan Cox <alc@cs.rice.edu>, and his description of the problem.
The bug was primarily in procfs_mem, but the mistake likely happened
due to the lack of vm system support for the operation. I added
better support for selective marking of page dirty flags so that
vm_map_pageable(wiring) will not cause this problem again.
The code in procfs_mem is now less bogus (but maybe still a little
so.)
centric rather than VM-centric to fix a problem with errors not being
detectable when the header is read.
Killed exech_map as a result of these changes.
There appears to be no performance difference with this change.
Lookup isn't done every time the system goes idle now, but it can still
take > 1800 instructions in the worst case, so if cpu interrupts are kept
disabled then it might lose 20 characters of sio input at 115200 bps.
Fixed style in vm_page_zero_idle().
functions if DDB is available. The remaining occurences are usually
only inlined and thus not available in DDB.
I'm sure Bruce will have 23 additions to these 30 lines of code, but
at least it's a starting point. ;-)
address outside of the process's address space.
Now it matches its man page :-). Closes PR# 2682.
Discussed with: bde
Submitted by: Jonathan Lemon <jlemon@americantv.com>
print "at <not configured>" for iobase == -1 (autodetect not happens)
and not print anything for iobase == -2 (none)
Old code treat this two special config numbers as big port numbers.
supports All Cyrix CPUs, IBM Blue Lightning CPU and NexGen (now AMD)
Nx586 CPU, and initialize special registers of Cyrix CPU and msr of
IBM Blue Lightning CPU.
If revision of Cyrix 6x86 CPU < 2.7, CPU cache is enabled in
write-through mode. This can be disabled by kernel configuration
options.
Reviewed by: Bruce Evans <bde@freebsd.org> and
Jordan K. Hubbard <jkh@freebsd.org>
Print the stack pointer together with the frame pointer in the trap,
syscall and interrupt messages. The frame pointer is not very useful
for locating syscall args since syscall functions don't have a frame
pointer.
Print all the numbers in the trap, syscall and interrupt messages in
the default radix. The syscall number was confusing because it was
printed in decimal.
Use %#n format more and 0x%x less. 0x%x of course doesn't work with
a variable radix. ddb is now fairly consistent about using %+#n to
print all numbers. It omits the '+' for signed numbers the '#' in a
few cases (e.g., for function args) to save space.
at runtime.
etc/make.conf:
Nuked HAVE_FPU option.
lib/msun/Makefile:
Always build the i387 objects. Copy the i387 source files at build
time so that the i387 objects have different names. This is simpler
than renaming the files in the cvs repository or repeating half of
bsd.lib.mk to add explicit rules.
lib/msun/src/*.c:
Renamed all functions that have an i387-specific version by adding
`__generic_' to their names.
lib/msun/src/get_hw_float.c:
New file for getting machdep.hw_float from the kernel.
sys/i386/include/asmacros.h:
Abuse the ENTRY() macro to generate jump vectors and associated code.
This works much like PIC PLT dynamic initialization. The PIC case is
messy. The old i387 entry points are renamed. Renaming is easier
here because the names are given by macro expansions.
Changed it from 4 to 16 for i386's. It can be anything for i386's,
but compiler options limit it to a power of 2, and assembler and
linker deficiencies limit it to a small power of 2 (<= 16).
We use 16 in the kernel to get smaller tables (see Makefile.i386 and
<machine/asmacros.h>). We still use the default of 4 in user mode.
Use HISTCOUNTER instead of (*kcount) in the definition of KCOUNT()
for consistency with other macros.
changes, so don't expect to be able to run the kernel as-is (very well)
without the appropriate Lite/2 userland changes.
The system boots and can mount UFS filesystems.
Untested: ext2fs, msdosfs, NFS
Known problems: Incorrect Berkeley ID strings in some files.
Mount_std mounts will not work until the getfsent
library routine is changed.
Reviewed by: various people
Submitted by: Jeffery Hsu <hsu@freebsd.org>
complained so it cannot be entirely bad :-)
I include the email that probably explains it for people who already know:
> >Compiling with -O3 inlines functions. However the function that is being
> >inlined in makeinfo.c (add_word_args()) is a vararg function and must not be
> >inlined.
> >
> >The code in question is K&R style, and AFIK, there is no way for the compiler
> >to determine that the function uses vararg. Either change the code to use
> >prototypes, or use stdarg, or add a directive to prevent inlining.
>
> Not declaring a varargs function as varargs before it is used gives
> undefined behaviour.
>
> However, in practice the bug is probably in FreeBSD's <varargs.h>, which
> doesn't use gcc's __builtin_next_arg(). gcc should notice that it is
> used and not inline functions that have it. <stdarg.h.> uses it, but I
> think there's another gcc builtin that it should be using.
Patch attached. The ellipsis causes gcc to flag this as a varargs function,
and the name "__builtin_va_alist" is special cased in gcc to hide the last
argument in the arglist.
Reviewed by: bde & phk
Submitted by: jlemon@americantv.com (Jonathan Lemon)
I have code to calibrate the overhead fairly accurately, but there
is little point in using it since it is most accurate on machines
where an estimate of 0 works well. On slow machines, the accuracy
of DELAY() has a large variance since it is limited by the resolution
of getit() even if the initial delay is calibrated perfectly.
Use fixed point and long longs to speed up scaling in DELAY().
The old method slowed down a lot when the frequency became variable.
Assume the default frequency for short delays so that the fixed
point calculation can be exact.
Fast scaling is only important for small delays. Scaling is done
after looking at the counter and outside the loop, so it doesn't
decrease accuracy or resolution provided it completes before the
delay is up. The comment in the code is still confused about this.
Disabling npx0 works right now.
Don't reference `npxdriver' if npx0 is not configured. Not configuring
npx0 doesn't quite work yet.
Don't clear potential non-npx pcb flags in setregs().
not lazy-fault page table pages. Update the copyout support to take
that into account. This should fix some segfault problems on such
machines.
After a short test period, we'll move this into 2.2.
Submitted by: Stephen McKay <syssgm@devetir.qld.gov.au>
called early for console i/o. The timer is usually in BIOS mode
if it isn't explicitly initialized. Then it counts twice as fast
and has a max count of 65535 instead of 11932. The larger count
tended to cause infinite loops for delays of > 20 us. Such delays
are rare. For syscons and kbdio, DELAY() is only called early
enough to matter for ddb input after booting with -d, and the delay
is too small to matter (and too small to be correct) except in the
PC98 case. For pcvt, DELAY() is not used for small delays (pcvt
uses its own broken routine instead of the standard broken one),
but some versions call DELAY() with a large arg when they unnecessarily
initialize the keyboard for doing console output. The problem is
more serious for pcvt because there is always some early console
output.
Guard against the i8254 timer being partially or incorrectly
initialized. This would have prevented the endless loop.
Should be in 2.2.
I have no idea if this works since I don't have one of the cards to test.
I also don't know what the LINT and GENERIC entries should look like,
so I just made up some values for now and left them commented out.
Someone who knows the factory settings for a Pro/10, please contact me!
Submitted-By: Javier Martín Rueda <jmrueda@diatel.upm.es>
when allocating memory for network buffers at interrupt time. This is due
to inadequate checking for the new mcl_map. Fixed by merging mb_map and
mcl_map into a single mb_map.
Reviewed by: wollman
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
- the operands for bt, bts, arpl and `enter' were reversed.
- btr was reported as bts (with the correct operand order).
- cmpxchg was misplaced. It was misplaced differently in the
comments. It is misplaced differently again in the i486 manual.
I put it where the i586 manual and gas say it is.
- fucompp was misplaced.
- the rr table for(s) some versions of fstp, fcom and fcomp was non-null.
This caused some invalid opcodes to be reported as "" instead of as
"<bad instruction>".
- the word and long versions of the fi* instructions were reversed.
- aaa and daa were reversed.
Fixed bugs involving unusual operand sizes:
- 32-bit registers weren't always forced for bswap or for moves to and
from special registers.
- the operand sizes weren't reported for [l]call or [l]jmp.
- displacements weren't truncated mod 2^16 when the operand size was
16-bit.
- too-large displacements and offsets were fetched, and too-large
offsets were reported, when the operand size was 16-bit.
- sign extended immediate bytes were extended too far when the operand
size was 16-bit.
Fixed bugs involving usual operand sizes:
- 8-bit source registers weren't forced for mov[sz]b[wl].
- 16-bit source registers weren't forced for mov[sz]w[wl].
- immediate bytes were sometimes reported as sign extended even for
byte operations. Same for immediate words in word operations.
- the immediate byte was not reported as sign extended for `push'.
Finished Pentium support:
- cpuid, cmpxchg8b and rsm were missing.
Finished i287 support:
- fneni, fndisi and fsetpm were missing. These are harmless nops on
later FPUs.
Improvements:
- report invalid opcodes 0xd6 and 0xf1 using .byte. They are special
in not causing invalid operand exceptions when executed.
- report the immediate byte for unusual aam and aad instuctions.
Immediate bytes other than 0x0a always worked and are documented to
work on Pentiums.
This code was sent to me by Bruce Evans, and seems to fix some
possible kernel panic in case of an execution error. It did not
cause any problems on my system, but I did never observe the
problem this patch is supposed to fix, anyway.
This patch is a NOP, unless the kernel is built with "options
USER_LDT", and doesn't affect the GENERIC kernel for this reason.
I want to have it in 2.2: it fixes a bug ...
Submitted by: bde
also implies VM_PROT_EXEC. We support it that way for now,
since the break system call by default gives VM_PROT_ALL. Now
we have a better chance of coalesing map entries when mixing
mmap/break type operations. This was contributing to excessive
numbers of map entries on the modula-3 runtime system. The
problem is still not "solved", but the situation makes more
sense.
Eventually, when we work on architectures where VM_PROT_READ
is orthogonal to VM_PROT_EXEC, we will have to visit this
issue carefully (esp. regarding security issues.)