Commit Graph

445 Commits

Author SHA1 Message Date
Peter Wemm
477a642cee Man the liferafts! Here comes the long awaited SMP -> -current merge!
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!
1997-04-26 11:46:25 +00:00
Peter Wemm
92da7e012d Send this to the Attic so there's no mixups over which kern_lock.c is in
use in -current.
1997-04-21 13:39:56 +00:00
Peter Wemm
e108835bbc Unused variable (upobj is now purely handled within pmap) 1997-04-14 03:40:42 +00:00
John Dyson
5856e12e69 Fully implement vfork. Vfork is now much much faster than even our
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.
1997-04-13 01:48:35 +00:00
Peter Wemm
a2a1c95c10 The biggie: Get rid of the UPAGES from the top of the per-process address
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.
1997-04-07 07:16:06 +00:00
Peter Wemm
2100d64585 Commit a typo fix that's been sitting in my tree for ages, quite forgotten.
The typo was detected once apon a time with the -Wunused compile option.
The result was that a block of code for implementing
madvise(.. MADV_SEQUENTIAL..) behavior was "dead" and unused, probably
negating the effect of activating the option.

Reviewed by: dyson
1997-04-06 16:16:11 +00:00
John Dyson
7d78abc9d9 Make vm_map_protect be more complete about map simplification. This
is useful when a process changes it's page range protections very
much.
Submitted by:	Alan Cox <alc@cs.rice.edu>
1997-04-06 03:04:31 +00:00
John Dyson
15cb98465f Correction to the prototype for vm_fault. 1997-04-06 02:30:56 +00:00
John Dyson
a04c970a7a Fix the gdb executable modify problem. Thanks to the detective work
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.)
1997-04-06 02:29:45 +00:00
Bruce Evans
3f39dbc52d Removed potentially harmful garbage <vm/lock.h> and fixed bogus
use of it.  It was actually harmless because the use was null due
to fortuitous include orders and identical (wrong) idempotency
macros.
1997-04-01 08:39:07 +00:00
David Greenman
9caaadb63a Changed the way that the exec image header is read to be filesystem-
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.
1997-03-31 11:11:26 +00:00
Bruce Evans
3ac4d1ef0c Don't #include <sys/fcntl.h> in <sys/file.h> if KERNEL is defined.
Fixed everything that depended on getting fcntl.h stuff from the wrong
place.  Most things don't depend on file.h stuff at all.
1997-03-23 03:37:54 +00:00
John Dyson
c5d593ae63 Fix a significant error in the accounting for pre-zeroed pages. This
is a candidate for RELENG_2_2...
1997-03-23 02:44:54 +00:00
John Dyson
eb2c768ebb When removing IN_RECURSE support during the Lite/2 merge, read/write
to/from mmaped regions was broken.  This commit fixes the breakage, and
uses the new Lite/2 locking mechanisms.
1997-03-08 04:33:47 +00:00
Bruce Evans
2f558c3e59 Removed a wrong LK_INTERLOCK flag. 1997-02-27 15:38:41 +00:00
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Bruce Evans
697030ed3d Removed vestiges of Mach lock types.
vm_map.h:
Removed #include of <sys/proc.h>.  curproc is only used in some macros
and users of the macros already include <sys/proc.h>.
1997-02-18 14:07:03 +00:00
Garrett Wollman
10825343b0 Provide an alternative interface to contigmalloc() which allows a specific
map to be used when allocating the kernel va (e.g., mb_map).  The VM
gurus may want to look this over.
1997-02-13 19:37:40 +00:00
John Dyson
996c772f58 This is the kernel Lite/2 commit. There are some requisite userland
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>
1997-02-10 02:22:35 +00:00
John Dyson
5069bf5747 Another fix to inheriting shared segments. Do the copy on write
thing if needed.
Submitted by:	Alan Cox <alc@cs.rice.edu>
1997-01-31 04:10:41 +00:00
David Greenman
098415100b Added a check/panic for v_usecount being 0 (no vnode reference) in
vnode_pager_alloc().
1997-01-24 22:20:23 +00:00
John Dyson
fed9a9032e Fix two problems where a NULL object is dereferenced. One problem
was in the VM_INHERIT_SHARE case of vmspace_fork, and also in vm_map_madvise.
Submitted by:	Alan Cox <alc@cs.rice.edu>
1997-01-22 01:34:48 +00:00
John Dyson
6e20a16589 Make MADV_FREE work better. Specifically, it did not wait for
the page to be unbusy, and it caused some algorithmic problems
as a result.  There were some other problems with it also, so
this is a general cleanup of the code.
Submitted by:	Douglas Crosher <dtc@scrooge.ee.swin.oz.au> and myself.
1997-01-20 02:25:14 +00:00
John Dyson
afa07f7e83 Change the map entry flags from bitfields to bitmasks. Allows
for some code simplification.
1997-01-16 04:16:22 +00:00
David Greenman
649c409d03 Fix bug related to map entry allocations where a sleep might be attempted
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
1997-01-15 20:46:02 +00:00
Bruce Evans
16a02c1105 Removed redundant spl0()'s from kernel processes. They were work-arounds
for a bug in fork().
1997-01-15 19:05:08 +00:00
Jordan K. Hubbard
1130b656e5 Make the long-awaited change from $Id$ to $FreeBSD$
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.
1997-01-14 07:20:47 +00:00
John Dyson
d4a272db61 Slightly correct the code that moves pages from the active to the
inactive queue.  This is only a minor performance improvement, but will
not affect perf on machines that don't have ref bits.
1997-01-11 07:22:24 +00:00
John Dyson
9b5a5d81be Prepare better for multi-platform by eliminating another required
pmap routine (pmap_is_referenced.)  Upper level recoded to use
pmap_ts_referenced.
1997-01-11 07:19:02 +00:00
John Dyson
106031ef73 Undo the collapse breakage (swap space usage problem.) 1997-01-03 17:02:28 +00:00
John Dyson
3c018e7214 Guess what? We left alot of the old collapse code that is not needed
anymore with the "full" collapse fix that we added about 1yr ago!!!  The
code has been removed by optioning it out for now, so we can put it back
in ASAP if any problems are found.
1997-01-01 04:45:05 +00:00
John Dyson
8cc7e047a3 A very significant improvement in the management of process maps
and objects.  Previously, "fancy" memory management techniques
such as that used by the M3 RTS would have the tendancy of chopping
up processes allocated memory into lots of little objects.  Alan
has come up with some improvements to migtigate the sitution to
the point where even the M3 RTS only has one object for bss and
it's managed memory (when running CVSUP.)  (There are still cases where the
situation isn't improved when the system pages -- but this is much much
better for the vast majority of cases.)  The system will now be able
to much more effectively merge map entries.

Submitted by:	Alan Cox <alc@cs.rice.edu>
1996-12-31 16:23:38 +00:00
John Dyson
d0aea04fe0 Let the VM system know that on certain arch's that VM_PROT_READ
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.)
1996-12-30 05:31:21 +00:00
John Dyson
bc0d333478 EEEK!!! useracc and kernacc didn't lock their respective
maps.  Additionally, eliminate the map->hint distortion
associated with useracc.  That may/may-not be the "right"
thing to do -- but time will tell.
Submitted by:	Partially by Alan Cox <alc@cs.rice.edu>
1996-12-30 03:56:11 +00:00
John Dyson
595236df9b Superficial cleanup of comment. 1996-12-29 02:33:12 +00:00
John Dyson
b7b2aac2b6 Eliminate the redundancy due to the similarity between the routines
vm_map_simplify and vm_map_simplify_entry.  Make vm_map_simplify_entry
handle wired maps so that we can get rid of vm_map_simplify.  Modify
the callers of vm_map_simplify to properly use vm_map_simplify_entry.
Submitted by:	Alan Cox <alc@cs.rice.edu>
1996-12-28 23:07:49 +00:00
John Dyson
94328e9057 The code unnecessarily created an object with no handle up-front, which
has the negative effect of disabling some map optimizations.  This
patch defers the creation of the object until it needs to be at fault time.
Submitted by:	Alan Cox <alc@cs.rice.edu>
1996-12-28 22:40:44 +00:00
Joerg Wunsch
e9822d926c Make DFLDSIZ and MAXDSIZ fully-supported options.
"Don't forget to do a ``make depend''" :-)
1996-12-22 23:17:09 +00:00
John Dyson
7aaaa4fd5d Implement closer-to POSIX mlock semantics. The major difference is
that we do allow mlock to span unallocated regions (of course, not
mlocking them.)  We also allow mlocking of RO regions (which the old
code couldn't.)  The restriction there is that once a RO region is
wired (mlocked), it cannot be debugged (or EVER written to.)

Under normal usage, the new mlock code will be a significant improvement
over our old stuff.
1996-12-14 17:54:17 +00:00
John Dyson
0362d7d737 Expunge inlines... 1996-12-07 07:44:05 +00:00
John Dyson
62487bb4db Fix a map entry leak problem found by DG. Also, de-inline a function
vm_map_entry_dispose, because it won't help being inlined.
1996-12-07 06:19:37 +00:00
John Dyson
cdc2c29161 Make vm_map_insert much more intelligent in the MAP_NOFAULT case so
that map entries are coalesced when appropriate.  Also, conditionalize
some code that is currently not used in vm_map_insert.  This mod
has been added to eliminate unnecessary map entries in buffer map.

Additionally, there were some cases where map coalescing could be done
when it shouldn't.  That problem has been resolved.
1996-12-07 00:03:43 +00:00
John Dyson
09e0c6ccdd Implement a new totally dynamic (up to MAXPHYS) buffer kva allocation
scheme.  Additionally, add the capability for checking for unexpected
kernel page faults.  The maximum amount of kva space for buffers hasn't
been decreased from where it is, but it will now be possible to do so.

This scheme manages the kva space similar to the buffers themselves.  If
there isn't enough kva space because of usage or fragementation, buffers
will be reclaimed until a buffer allocation is successful.  This scheme
should be very resistant to fragmentation problems until/if the LFS code
is fixed and uses the bogus buffer locking scheme -- but a 'fixed' LFS
is not likely to use such a scheme.

Now there should be NO problem allocating buffers up to MAXPHYS.
1996-11-30 22:41:49 +00:00
John Dyson
e0c5a895f1 Make the kernel smaller with at worst a neutral effect on perf by
de-inlining some VM calls.  (Actually, I measured a small improvement.)
1996-11-28 23:15:07 +00:00
John Dyson
5b0a74089d Improve the locality of reference for variables in vm_page and
vm_kern by moving them from .bss to .data.  With this change,
there is a measurable perf improvement in fork/exec.
1996-11-17 02:38:31 +00:00
John Dyson
db2c0faa4c Vastly improved contigmalloc routine. It does not solve the
problem of allocating contiguous buffer memory in general, but
make it much more likely to work at boot-up time.  The best
chance for an LKM-type load of a sound driver is immediately
after the mount of the root filesystem.

This appears to work for a 64K allocation on an 8MB system.
1996-11-05 04:19:08 +00:00
John Dyson
851c12ff1d Change mmap to use OBJT_DEFAULT instead of OBJT_SWAP by default
for anonymous objects.  The system will automatically change the
type to SWAP if needed (for size or pageout reasons.)
1996-10-29 22:07:11 +00:00
Poul-Henning Kamp
281cd9b020 The way we get a vnode for swapdev is not quite kosher. In particular
it breaks in the DEVFS_ROOT case.  replicate a bit too much of bdevvp()
in here to circumvent the problem.  The real problem is the magic that
lives in bdevsw[1].
1996-10-27 22:31:00 +00:00
John Dyson
fcae040bc0 Remove a bogus optimization in the mmap code. It is superfluous,
and at best is the same speed as the unoptimized code.  At worst, it
slows down trivial programs.
1996-10-24 02:56:23 +00:00
John Dyson
a669a6e9a9 Make processes waken up eligible for immediate swap-in. 1996-10-17 02:58:20 +00:00