Submitted by: Andrew McRae <andrew@mega.com.au>
Some initial commits from the pcmcia stuff, to make life easier for the
testers.
We will use the name "pccard" since that is really the buzzword at present.
notebooks where a powerfail condition (external power drop; battery
state low) is signalled by an NMI. Makes it beep instead of panicing.
Reviewed by: davidg
proc or any VM system structure will have to be rebuilt!!!
Much needed overhaul of the VM system. Included in this first round of
changes:
1) Improved pager interfaces: init, alloc, dealloc, getpages, putpages,
haspage, and sync operations are supported. The haspage interface now
provides information about clusterability. All pager routines now take
struct vm_object's instead of "pagers".
2) Improved data structures. In the previous paradigm, there is constant
confusion caused by pagers being both a data structure ("allocate a
pager") and a collection of routines. The idea of a pager structure has
escentially been eliminated. Objects now have types, and this type is
used to index the appropriate pager. In most cases, items in the pager
structure were duplicated in the object data structure and thus were
unnecessary. In the few cases that remained, a un_pager structure union
was created in the object to contain these items.
3) Because of the cleanup of #1 & #2, a lot of unnecessary layering can now
be removed. For instance, vm_object_enter(), vm_object_lookup(),
vm_object_remove(), and the associated object hash list were some of the
things that were removed.
4) simple_lock's removed. Discussion with several people reveals that the
SMP locking primitives used in the VM system aren't likely the mechanism
that we'll be adopting. Even if it were, the locking that was in the code
was very inadequate and would have to be mostly re-done anyway. The
locking in a uni-processor kernel was a no-op but went a long way toward
making the code difficult to read and debug.
5) Places that attempted to kludge-up the fact that we don't have kernel
thread support have been fixed to reflect the reality that we are really
dealing with processes, not threads. The VM system didn't have complete
thread support, so the comments and mis-named routines were just wrong.
We now use tsleep and wakeup directly in the lock routines, for instance.
6) Where appropriate, the pagers have been improved, especially in the
pager_alloc routines. Most of the pager_allocs have been rewritten and
are now faster and easier to maintain.
7) The pagedaemon pageout clustering algorithm has been rewritten and
now tries harder to output an even number of pages before and after
the requested page. This is sort of the reverse of the ideal pagein
algorithm and should provide better overall performance.
8) Unnecessary (incorrect) casts to caddr_t in calls to tsleep & wakeup
have been removed. Some other unnecessary casts have also been removed.
9) Some almost useless debugging code removed.
10) Terminology of shadow objects vs. backing objects straightened out.
The fact that the vm_object data structure escentially had this
backwards really confused things. The use of "shadow" and "backing
object" throughout the code is now internally consistent and correct
in the Mach terminology.
11) Several minor bug fixes, including one in the vm daemon that caused
0 RSS objects to not get purged as intended.
12) A "default pager" has now been created which cleans up the transition
of objects to the "swap" type. The previous checks throughout the code
for swp->pg_data != NULL were really ugly. This change also provides
the rudiments for future backing of "anonymous" memory by something
other than the swap pager (via the vnode pager, for example), and it
allows the decision about which of these pagers to use to be made
dynamically (although will need some additional decision code to do
this, of course).
13) (dyson) MAP_COPY has been deprecated and the corresponding "copy
object" code has been removed. MAP_COPY was undocumented and non-
standard. It was furthermore broken in several ways which caused its
behavior to degrade to MAP_PRIVATE. Binaries that use MAP_COPY will
continue to work correctly, but via the slightly different semantics
of MAP_PRIVATE.
14) (dyson) Sharing maps have been removed. It's marginal usefulness in a
threads design can be worked around in other ways. Both #12 and #13
were done to simplify the code and improve readability and maintain-
ability. (As were most all of these changes)
TODO:
1) Rewrite most of the vnode pager to use VOP_GETPAGES/PUTPAGES. Doing
this will reduce the vnode pager to a mere fraction of its current size.
2) Rewrite vm_fault and the swap/vnode pagers to use the clustering
information provided by the new haspage pager interface. This will
substantially reduce the overhead by eliminating a large number of
VOP_BMAP() calls. The VOP_BMAP() filesystem interface should be
improved to provide both a "behind" and "ahead" indication of
contiguousness.
3) Implement the extended features of pager_haspage in swap_pager_haspage().
It currently just says 0 pages ahead/behind.
4) Re-implement the swap device (swstrategy) in a more elegant way, perhaps
via a much more general mechanism that could also be used for disk
striping of regular filesystems.
5) Do something to improve the architecture of vm_object_collapse(). The
fact that it makes calls into the swap pager and knows too much about
how the swap pager operates really bothers me. It also doesn't allow
for collapsing of non-swap pager objects ("unnamed" objects backed by
other pagers).
fail on new hardware (Compaq Prolinea and Compaq Prosignea), and that
doesn't erroneously identify old mech. 2 chip sets as using mech. 1.
(See section 3.6.4.1.1 of the PCI bus specs rev. 2.0)
a related bug in some of the new 'foo'boot bootstrap code that has been
added over the past months. This change makes it no longer necessary
for the bootstrap to fix up the path (i.e. it can be removed).
include/signal.h:
There was massive namespace pollution from including <sys/types.h>.
POSIX functions were declared even when _ANSI_SOURCE is defined.
sys.sys/signal.h:
NSIG was declared even if _ANSI_SOURCE or _POSIX_SOURCE is defined.
sig_atomic_t wasn't declared if _POSIX_SOURCE is defined.
Declare a typedef for signal handling functions and use it to
unobfuscate declarations and to avoid half-baked function types
that cause unwanted compiler warnings at certain warning levels.
Fix confusing comment about SA_RESTART.
sys/i386/include/signal.h:
This has to be included to get the declaration of sig_atomic_t even
when _ANSI_SOURCE is defined, so be more careful about polluting
the ANSI namespace.
Uniformize idempotency ifdefs.
when syscons stops mapping the console to minor MAXCONS. There is
usually no corresponding device in /dev, and the correct device has
minor 0.
cons.c:
Initialize cn_tty properly, so that CPU_CONSDEV can work.
Comment about too many variants of the console tty pointer.
machdep.c:
Return device NODEV and not error EFAULT when there is no console device.
Fix one such THING in code to match comment.
Sort IO_GSC* into numeric order and update comments about the gaps.
Sort common SCSI addresses into alphabetical order.
Remove bogus comments about com ports having i/o size 4.
Uniformize whitespace.
Uniformize case in hex digits.
This file is very incomplete. In particular, it doesn't mention any
network cards. This doesn't matter much for the base addresses, but
it means that the comments about which addresses are free are mostly
bogus. The i/o sizes are unreliable because of split address ranges
for many devices (VGA, wd). The i/o sizes are incomplete. In
particular, there are no sizes for SCSI controllers. The bt driver
still returns a truth value instead of a size.
- the major number wasn't checked, so accesses beyond the end of bdevsw[]
were possible. Bogus major numbers are easy to get because `sysctl -w'
doesn't handle dev_t's reasonably - it doesn't convert names to dev_t's
and it converts the number 1025 to the dev_t 0x35323031.
- Driver d_psize() functions return -1 to indicate error ENXIO or ENODEV
(the interface is too braindamaged to say which). -1 was interpreted
as a size and resulted in the bogus error ENOSPC.
- it was possible to set the dumpdev for devices without a d_psize()
function. This is equivalent to setting the dumpdev to NODEV except
it confuses sysctl.
- change a 512 to DEV_BSIZE. There is an official macro dtoc() for
converting "pages" to disk blocks but it is never used in /usr/src/sys.
There is much confusion between PAGE_SIZE sized pages and NBPG sized
pages. Maxmem consists of both.
Not fixed:
- there is nothing to invalidate the dumpdev if the media goes away.
This reduces the benefits of the early calculation of dumplo. Bounds
checking in the dump routines is relied on to reduce the risk of
damage and little would be lost by relying on the dump routines to
calculate dumplo.
- no attempt is made to stay away from the start of the device to
avoid clobbering labels.
Fix wrong && anachronistic comment about the type of bootdev.
Reviewed by: davidg
Submitted by: Bruce Evans
in machdep.c (it should use the global nmbclusters). Moved the calculation
of nmbclusters into conf/param.c (same place where nmbclusters has always
been assigned), and made the calculation include an extra amount based
on "maxusers". NMBCLUSTERS can still be overrided in the kernel config
file as always, but this change will make that generally unnecessary. This
fixes the "bug" reports from people who have misconfigured kernels seeing
the network hang when the mbuf cluster pool runs out.
Reviewed by: John Dyson
require specific partitions be mentioned in the kernel config
file ("swap on foo" is now obsolete).
From Poul-Henning:
The visible effect is this:
As default, unless
options "NSWAPDEV=23"
is in your config, you will have four swap-devices.
You can swapon(2) any block device you feel like, it doesn't have
to be in the kernel config.
There is a performance/resource win available by getting the NSWAPDEV right
(but only if you have just one swap-device ??), but using that as default
would be too restrictive.
The invisible effect is that:
Swap-handling disappears from the $arch part of the kernel.
It gets a lot simpler (-145 lines) and cleaner.
Reviewed by: John Dyson, David Greenman
Submitted by: Poul-Henning Kamp, with minor changes by me.
A phone call from Manfred quickly pointed up the fact that I got the conflict
check backwards. NOW we implement the conflict checking correctly! Wheesh!
to access it. setdelayed() actually ORs the bits in `idelayed' into
`ipending' and clears `idelayed'.
Call setdelayed() every (normal) clock tick to convert delayed
interrupts into pending ones.
Drivers can set bits in `idelayed' at any time to schedule an interrupt
at the next clock tick. This is more efficient than calling timeout().
Currently only software interrupts can be scheduled.
boot diskless with it, you get a panic because setconf() is only
called for mountroot == ffs_mountroot. It really needs to be called
no matter what manner of rootfs we have. I can't really say if
swapgeneric will work with a CD-ROM though. (I get the feeling I'm
the only one who uses swapgeneric these days anyway.)
there may even be LKMs.) Also, change the internal name of `unixdomain'
to `localdomain' since AF_LOCAL is now the preferred name of this family.
Declare netisr correctly and in the right place.
as side-effect, removed some legacy code that was necessary
when we called vm_fault inside of vm_fault_quick instead of using
the kernel/user space byte move routines.
the kernel at 0-640k; we haven't had the ability to do that since before
2.0R. Furthermore, I fail to see how putting an instruction at 0 and then
doing a .org 0x500 is going to prevent the stuff from getting clobbered
in the first place; a.out is just too stupid to know about sparse address
spaces.
Previously, this worked right if both AUTO_EOI_1 and AUTO_EOI_2 are
defined, but not if AUTO_EOI_1 is defined and AUTO_EOI_2 is not defined.
The latter case should be the default. DUMMY_NOPS should be the default
too. Currently there are only two NOPs slowing down rtcin() (although
there are no delays in writertc()) and several FASTER_NOPs slowing down
interrupt handling in vector.s.
Fix stack offsets for the (previously) unused untested
FAST_INTR_HANDLER_USES_ES case.
and #if defined (I586_CPU) thingies into identifycpu() so that we only
compile in what's actually needed for a given CPU. So far as I can tell,
none of my 386 machines generate a cpu_vendor code, so I made the extra vendor
and feature line conditional on I486_CPU and I586_CPU. (Otherwise we
print out a blank line which looks silly.)
kernels with 'options I586_CPU.'
The declaration for pentium_mhz is hidden inside an #ifdef I586_CPU,
but machdep.c refers to it whether I586_CPU is defined or not. This
temporary hack puts the offending code inside an #ifdef I586_CPU as
well so that a kernel without it will successfully compile.
I must emphasize the word 'temporary:' somebody needs to seriously
beat on the identifycpu() function with an #ifdef stick so that
I386_CPU, I486_CPU and I586_CPU will do the right things.
For those where it was easy, drivers were also fixed to call
dev_attach() during probe rather than attach (in keeping with the
new design articulated in a mail message five months ago). For
a few that were really easy, correct state tracking was added as well.
The `fd' driver was fixed to correctly fill in the description.
The CPU identify code was fixed to attach a `cpu' device. The code
was also massively reordered to fill in cpu_model with somethingremotely
resembling what identifycpu() prints out. A few bytes saved by using
%b to format the features list rather than lots of ifs.
drivers to protect DDB from being invoked while the console is in
process-controlled (i.e., graphics) mode.
Implement the logic to use this hook from within pcvt. (I'm sure
Søren will do the syscons part RSN).
I've still got one occasion where the system stalled, but my attempts
to trigger the situation artificially resulted int the expected
behaviour. It's hard to track bugs without the console and DDB
available. :-/
card. This is the braindamaged card with the 80186 CPU on it. It is
slow, probably not very good after all, but hey, if you have one lying
around doing nothing anyway...
Added the "zp0" driver to GENERIC.
to the user address space unless pcb_onfault is set. The code is currently
commented out because iBCS2 and process debugging parts of the kernel
need to be changed/fixed first.
To use this: recompile src/gnu/usr.bin/cc, compile your kernel. The
files you want to profile should be compiled with '-a -g'. "strip -x"
the kernel and run. You don't need to profile all files in the kernel.
My next commit is the program to extract the data from the running kernel.
messages like this:
wdc0 at 0x1f0-0x1f7 irq 14 on isa
wdc0: unit 0 (wd0): <ST506>
wd0: size unknown, using BIOS values: 615 cyl, 4 head, 17 sec, bytes/sec 512
npx0 at 0xf0-0xff irq 13 on motherboard
npx0: changing root device to wd0a
^^^^^^
The spurious 'npx0: ' pops up if you have a 386 with a 387 FPU.
New functions create - vm_object_pip_wakeup and pagedaemon_wakeup that
are used to reduce the actual number of wakeups.
New function vm_page_protect which is used in conjuction with some new
page flags to reduce the number of calls to pmap_page_protect.
Minor changes to reduce unnecessary spl nesting.
Rewrote vm_page_alloc() to improve readability.
Various other mostly cosmetic changes.
just thinking about it.
Two changes need to be made to allow 'config kernel swap generic' to
work properly without requiring any compile-time flags:
/usr/src/usr.sbin/config/mkswapconf.c: we need to define a dummy stub
for the setconf() function to replace the one in swapgeneric.c that
isn't available in non-generic configurations.
/usr/src/sys/i386/i386/autoconf.c: the -a boot flag causes setroot()
to be skipped and lets setconf() prompt the user for a root device.
If you skip setroot() in a non-generic kernel, you could get severely
hosed. To avoid this, we silently ignore the -a flag if rootdev != NODEV.
(rootdev is always initialized to NODEV in swapgeneric.c, so if
we find that rootdev is something other than NODEV, we know we're
not using a generic configuration.)
briefly over it, and see some serious architectural issues in this stuff.
On the other hand, I doubt that we will have any solution to these issues
before 2.1, so we might as well leave this in.
Most of the stuff is bracketed by #ifdef's so it shouldn't matter too much
in the normal case.
Reviewed by: phk
Submitted by: HOSOKAWA, Tatsumi <hosokawa@mt.cs.keio.ac.jp>
entire kernel.
Unfortunately we didn't send him a copy of the style guide before he did it.
I'm trying to find all the benign and downright sound bits and will commit
them without any other explanation than "YF fix" if they are merely cosmetic.
Reviewed by: phk
Submitted by: yves@dutncp8.tn.tudelft.nl (Yves Fonk)
some comparisons as it is more correct (we want the kernel page tables
included).
Reorganized some of the expressions for efficiency.
Fixed the new pmap_prefault() routine - it would sometimes pick up the
wrong page if the page in the shadow was present but the page in object
was paged out. The routine remains unused and commented out, however.
Explicitly free zero reference count page tables (rather than waiting
for the pagedaemon to do it).
Submitted by: John Dyson
Now it matches the man page and also the only other commercial implementation
i have found so far ( Solaris 2.x).
Changed the name from ss_base to ss_sp.
Handles at least Trantor T130 and ProAudioSpectrum adapters.
The pas driver has consequently been removed.
This driver can be configured without without interrupts.
Manpage to follow when PAS16 has been edited in.
Reviewed by: phk
Submitted by: Serge Vakulenko, <vak@cronyx.ru>
(Boot with the -D flag if you want symbols.)
Make it easier to extend `struct bootinfo' without losing either forwards
or backwards compatibility.
ddb_aout.c:
Get the symbol table from wherever the loader put it.
Nuke db_symtab[SYMTAB_SPACE].
boot.c:
Enable loading of symbols. Align them on a page boundary. Add printfs
about the symbol table sizes.
Pass the memory sizes to the kernel.
Fix initialization of `unit' (it got moved out of the loop).
Fix adding the bss size (it got moved inside an ifdef).
Initialize serial port when RB_SERIAL is toggled on.
Fix comments.
Clean up formatting of recently added code.
io.c:
Clean up formatting of recently added code.
netboot/main.c, machdep.c, wd.c:
Change names of bootinfo fields.
LINT:
Nuke SYMTAB_SPACE.
Fix comment about DODUMP.
Makefile.i386:
Nuke use of dbsym.
Exclude gcc symbols from kernel unless compiling with -g.
Remove unused macro.
Fix comments and formatting.
genassym.c:
Generate defines for some new bootinfo fields. Change names of old ones.
locore.s:
Copy only the valid part of the `struct bootinfo' passed by the loader.
Reserve space for symbol table, if any.
machdep.c:
Check the memory sizes passed by the loader, if any. Don't use them yet.
bootinfo.h:
Add a size field so that we can resolve some mismatches between the loader
bootinfo and the kernel boot info. The version number is not so good for
this because of historical botches and because it's harder to maintain.
Add memory size and symbol table fields. Change the names of everything.
Hacks to save a few bytes:
asm.S, boot.c, boot2.S:
Replace `ouraddr' by `(BOOTSEG << 4)'.
boot.c:
Don't statically initialize `loadflags' to 0. Disable the "REDUNDANT"
code that skips the BIOS variables. Eliminate `total'. Combine some
more printfs.
boot.h, disk.c, io.c, table.c:
Move all statically initialzed data to table.c.
io.c:
Don't put the A20 gate bits in a variable.
Moved various pmap 'bit' test/set functions back into real functions; gcc
generates better code at the expense of more of it. (pmap.c)
Fixed a deadlock problem with pv entry allocations (pmap.c)
Added a new, optional function 'pmap_prefault' that does clustered page
table preloading (pmap.c)
Changed the way that page tables are held onto (trap.c).
Submitted by: John Dyson
work (mi_switch() counted the last timeslice again but this didn't affect
the exiting process' rusage because the rusage has already been finalized).
Remove stale comment.
Put in the much shorter and cleaner version for the calibrate_cycle_counter
for the Pentium that Bruce suggested. Tested here on my Pentium and
it works okay.
sigreturn() sometimes failed for ordinary returns from signal handlers.
Failures of ordinary returns "can't happen" and are badly handled.
"Temporary" fix: allow users to corrupt PSL_RF. This is fairly
harmless. A correct fix would involve saving the old %eflags (and
perhaps the old segment registers) where the user can't get at them.
attempted to check for insecure and fatal eflags and segment
selectors, but missed many cases and got the IOPL check back to
front. The other syscalls didn't check at all.
sys_process.c, machdep.c:
Only allow PT_WRITE_U to write to the registers (ordinary and FP).
psl.h, locore.s, machdep.c:
Eliminate PSL_MBZ, PSL_MBO and PSL_USERCLR. We are not supposed
to assume anything about the reserved bits. Use PSL_USERCHANGE
and PSL_KERNEL instead. Rename PSL_USERSET to PSL_USER.
exception.s:
Define a private label for use by doreti when returning to user
mode fails.
machdep.c:
In syscalls, allow changing only the eflags that can be changed on
486's in user mode (no longer attempt to allow benign IOPL changes;
allow changing the nasty PSL_NT; don't allow changing the i586
bits).
Don't attempt to check all the cases involving invalid selectors
and %eip's. Just check for privilege violations and let the invalid
things cause a trap.
procfs_machdep.c:
Call the ptrace register functions to do all the work for reading
and writing ordinary registers and for single stepping.
trap.c:
Ignore traps caused by PSL_NT being set. Previously, users could
cause a fatal trap in user mode by setting PSL_NT and executing an
iret, and a fatal trap in kernel mode by setting PSL_NT and making
a syscall. PSL_NT was cleared too late and not in enough modes to
fix the problem.
Make all traps in user mode (except T_NMI) nonfatal.
Recover from traps caused by attempting to load invalid user
registers in doreti by restarting the traps so that they appear to
occur in user mode.
---
Fix bogons that I noticed while fixing the above:
psl.h:
Fix some comments.
Uniformize idempotency ifdef.
exception.s, machdep.c:
Remove rsvd[0-14]. rsvd0 hasn't been reserved since the 486 came
out. Replace rsvd0 by `align'. rsvd[0-11] used wrong (magic
non-unique) trap numbers. Replace rsvd[1-14] by rsvd.
locore.s:
Enable alignment check flag on 486's and 586's.
machdep.c:
Use a better type for kstack[].
Use TFREGP() to find the registers.
Reformat ptrace functions from SEF to something closer to KNF.
procfs_machdep.c:
The wrong pointer to the registers got fixed as a side effect.
Implement reading and writing of FP registers.
/proc/*/*regs now work (only) for processes that are in memory.
Clean up comments.
trap.c, trap.h:
Remove unused trap types.
unreachable case label in kdb_trap().
Use the correct case labels in kdb_trap() so that normal ddb entry doesn't
print a message.
Change all printf's to db_printf's. Now you can put a breakpoint at printf,
and ddb entry messages don't spam the syslog output.
Cosmetic:
Use ISPL() instead of magic numbers.
Don't compile the unused function kdb_kbd_trap().
Improve some asms.
Print the arg to Debugger().
much higher filesystem I/O performance, and much better paging performance. It
represents the culmination of over 6 months of R&D.
The majority of the merged VM/cache work is by John Dyson.
The following highlights the most significant changes. Additionally, there are
(mostly minor) changes to the various filesystem modules (nfs, msdosfs, etc) to
support the new VM/buffer scheme.
vfs_bio.c:
Significant rewrite of most of vfs_bio to support the merged VM buffer cache
scheme. The scheme is almost fully compatible with the old filesystem
interface. Significant improvement in the number of opportunities for write
clustering.
vfs_cluster.c, vfs_subr.c
Upgrade and performance enhancements in vfs layer code to support merged
VM/buffer cache. Fixup of vfs_cluster to eliminate the bogus pagemove stuff.
vm_object.c:
Yet more improvements in the collapse code. Elimination of some windows that
can cause list corruption.
vm_pageout.c:
Fixed it, it really works better now. Somehow in 2.0, some "enhancements"
broke the code. This code has been reworked from the ground-up.
vm_fault.c, vm_page.c, pmap.c, vm_object.c
Support for small-block filesystems with merged VM/buffer cache scheme.
pmap.c vm_map.c
Dynamic kernel VM size, now we dont have to pre-allocate excessive numbers of
kernel PTs.
vm_glue.c
Much simpler and more effective swapping code. No more gratuitous swapping.
proc.h
Fixed the problem that the p_lock flag was not being cleared on a fork.
swap_pager.c, vnode_pager.c
Removal of old vfs_bio cruft to support the past pseudo-coherency. Now the
code doesn't need it anymore.
machdep.c
Changes to better support the parameter values for the merged VM/buffer cache
scheme.
machdep.c, kern_exec.c, vm_glue.c
Implemented a seperate submap for temporary exec string space and another one
to contain process upages. This eliminates all map fragmentation problems
that previously existed.
ffs_inode.c, ufs_inode.c, ufs_readwrite.c
Changes for merged VM/buffer cache. Add "bypass" support for sneaking in on
busy buffers.
Submitted by: John Dyson and David Greenman
shifting. Also correct the original code as Garrett noticed it in mail.
Leave the mishandled code in to use it later if future versions of gcc
are correct. The code was part of the calibrate_cyclecounter routine to
get the speed of the pentium chip.
Remove bogus input operands for fnsave(), fnstcw() and fnstsw().
Change all fwait's to fnop's. This might help avoid hardware bugs.
Wait after fninit with an fnop. This should be safer now.
Fix some spelling and formatting errors.
Use natural sizes for control and status words (u_short, promotes to int).
Don't clobber the SWI_CLOCK_MASK bits in npx0_imask when using IRQ13.
Set the devconf state correctly (always busy, if configured). Improve
code for npx_registerdev() a little (gcc can't keep id->id_unit in a
register for some reason). Don't register a nonexistent npx device.
Print a useful message in npxattach() again (delete references to errors
and not the whole message). Don't print "387 emulator" if there is no
emulator in the kernel.
Use %p for pointers in error messages.
Don't clobber the FPU state when there is an FPU exception. Just clear
the exception flags (after saving the flags as before). This allows
debuggers and SIGFPE handlers to look at the full exception state.
SIGFPE handlers should normally return via longjmp(), which restores a
good FPU state (as before). Returning from a SIGFPE handler may leave
the FPU in the wrong state (as before).
Clear the busy latch _after_ clearing the exception flags so that there
is less chance of getting a bogus h/w interrupt for a control operation.
Clear the saved exception status word when the next FPU instruction is
excuted so that it doesn't stick around until the next exception.
Clear the busy latch after fnsave() in npxsave() in case it was set when
npxsave() was called.
- /sys/i386/i386/swapgeneric.c is just plain broke. But fear not, for I
have unbroken it. One thing that swapgeneric.c does is walk through the
list of configured devices searching for a boot device. The only easy
way to accomplish this in 2.0 is to use Garret Wollman's kern_devconf
stuff. *BUT*, the head of the kern_devconf linked list (dc_list) is declared
static in /sys/kern/kern_devconf.c. This means that swapgeneric.c can't
see it at link time. I had to remove the 'static' keyword to get around
this little problem. I hope this doesn't break anything anywhere.
*Furthermore,* there's a small matter of making the call to setconf()
in swapgeneric.c disappear when 'config kernel swap generic' isn't used.
You could change /sbin/config to create a dummy setconf() function in
swapkernel.c, but that seems messy somehow. (It's also someting of an
'it isn't broken, why are you fixing it' situation.) My solution was to
do what the NetBSD people did and put an #ifdef GENERIC around the call
to setconf(). If your kernel is called GENERIC or you define 'options
GENERIC,' then you can use 'config kernel swap generic' and it'll work.
That aside, the upshot is that: a) swapgeneric.c actually works, and
and b) the -a boot flag now works as well. If you boot with -a, as in
"Boot: wd(0,a)/kernel -a" you will be presented with a 'root device?'
prompt after the autoconfig phase, at which point you can specify what
device you want mounted as root. Regrettably, you can't specify an NFS
filesystem. Yet. Three files are affected: /sys/i386/i386/swapgeneric.c,
/sys/i386/i386/autoconf.c and /sys/kern/kern_devconf.c.
Submitted by: wpaul
Move definition of `stat_imask' to clock.c.
clock.c:
Rename `rtcmask' to `stat_imask' and export it. Rename `clkmask' to
`clk_imask' for consistency.
Only calculate TIMER_DIV(hz) once.
Merge debugging and "garbage" code to produce debugging code and format the
output better.
Make writertc() static inline and use it everywhere. Now all accesses to
the clock registers go through rtcin() and writertc().
Move rtc initialization to cpu_initclocks().
Merge enablertclock() with cpu_initclocks() and remove enablertclock().
The extra entry point was just a leftover from 1.1.5.
Fix single-stepping of emulated FPU instructions.
Don't panic if an FPU instruction is attempted but there is no FPU
and no FPU emulator is configured.
Keep track of interrupt nesting level. It is normally 0
for syscalls and traps, but is fudged to 1 for their exit
processing in case they metamorphose into an interrupt
handler.
i386/genassym.c;
Remove support for the obsolete pcb_iml and pcb_cmap2.
Add support for pcb_inl.
i386/swtch.s:
Fudge the interrupt nesting level across context switches and in
the idle loop so that the work for preemptive context switches
gets counted as interrupt time, the work for voluntary context
switches gets counted mostly as system time (the part when
curproc == 0 gets counted as interrupt time), and only truly idle
time gets counted as idle time.
Remove obsolete support (commented out and otherwise) for pcb_iml.
Load curpcb just before curproc instead of just after so that
curpcb is always valid if curproc is. A few more changes like
this may fix tracing through context switches.
Remove obsolete function swtch_to_inactive().
include/cpu.h:
Use the new interrupt nesting level variable to implement a
non-fake CLF_INTR() so that accounting for the interrupt state
works.
You can use top, iostat or (best) an up to date systat to see
interrupt overheads. I see the expected huge interrupt overheads
for ISA devices (on a 486DX/33, about 55% for an IDE drive
transferring 1250K/sec and the same for a WD8013EBT network card
transferring 1100K/sec). The huge interrupt overheads for serial
devices are unfortunately normally invisible.
include/pcb.h:
Remove the obsolete pcb_iml and pcb_cmap2. Replace them by
padding to preserve binary compatibility.
Use part of the new padding for pcb_inl.
isa/icu.s:
isa/vector.s:
Keep track of interrupt nesting level.
of config so YOU MUST RECOMPILE CONFIG. Modifying config was the cleanest
solution to integrating this driver into the tree which will become more
obvious in the next commit.
was supposed to have already been made, but got botched somewhere.
Don't clobber the last page of memory (where the message buffer is). Some
BIOS don't gratuitously wipe it out on reboot.
Alphabetize.
Write all i/o functions in sleep so that we don't use anything from
NetBSD.
Restore the correct type of u_int for ports. This saves a whole cycle
per i/o on 486's.
Change `inline' back to __inline to avoid compiler warnings with
-Wreally-all.
Don't implement bdb() unless BDE_DEBUGGER is defined. Declare bdb_exists
outside the function to avoid hundreds of compiler warnings.
Let the compiler pick the register in asms if possible.
Implement ffs() using inline asm(). gcc provides a slightly different
one. It was broken in gcc-2.4.5 but works now. Declaring a correct
version inline ensures getting a correct version. FreeBSD-1.1.5 has
an slow inline version but FreeBSD-2.0 has a library version (which
probably never gets used).
Do inb() and outb() without using %edx for constant ports below 0x100.
Remove casts to the same type in queue functions.
Declare prototypes for everything implemented i386/*.s and also for
everything that is normally implemented as an inline here (I don't
like the current complete dependency on gcc). Ifdef out the prototypes
that are declared elsewhere. THere should be a separate header to
declare things implemented in i386/*.s, but then it would be harder
to override declarations with inlines.
${UII}
with the current default exception (un)mask. There should be no such
processes unless you change the mask. Someday the mask should be
changed to the IEEE default of everything masked. The npx state
gets saved so that it can be checked and this may have the side effect
of fixing a bug that was reported for 1.1.5. (npx exceptions may
sometimes leak across exits and clobber another process. I can't see
how this can happen.)
Get some missing/wrong declarations from headers now that the headers
have them.
the following.
Move declarations to and from <machine/segments.h>. Make segment stuff
static if possible.
Remove unused (although initialized) global variables _default_ldt,
currentldt, _gsel_tss (rename the latter to the auto variable
gtel_tss).
Use "correct" and consistent types for interrupt handlers.
Remove a mailing address from the code.
Fix type mismatches found by adding prototypes.
Partly support BDE_DEBUGGER. Still broken by conflict with APM. Does
nothing if BDE_DEBUGGER is not defined.
Clean up prototypes and data declarations. Declare most of the segment
functions that are implemented in support.s. Make data private in
machdep.c if possible.
Parenthesize expressions in macros properly!
${Uniformize idempotency ifdef}.
to avoid compiler warnings.
Clean up prototypes: alphabetize; don't use redundant `extern' or
meaningless `extern inline'.
Uniformize idempotency ifdef.
