Commit Graph

144 Commits

Author SHA1 Message Date
John Dyson
2d8acc0f4a VM level code cleanups.
1)	Start using TSM.
	Struct procs continue to point to upages structure, after being freed.
	Struct vmspace continues to point to pte object and kva space for kstack.
	u_map is now superfluous.
2)	vm_map's don't need to be reference counted.  They always exist either
	in the kernel or in a vmspace.  The vmspaces are managed by reference
	counts.
3)	Remove the "wired" vm_map nonsense.
4)	No need to keep a cache of kernel stack kva's.
5)	Get rid of strange looking ++var, and change to var++.
6)	Change more data structures to use our "zone" allocator.  Added
	struct proc, struct vmspace and struct vnode.  This saves a significant
	amount of kva space and physical memory.  Additionally, this enables
	TSM for the zone managed memory.
7)	Keep ioopt disabled for now.
8)	Remove the now bogus "single use" map concept.
9)	Use generation counts or id's for data structures residing in TSM, where
	it allows us to avoid unneeded restart overhead during traversals, where
	blocking might occur.
10)	Account better for memory deficits, so the pageout daemon will be able
	to make enough memory available (experimental.)
11)	Fix some vnode locking problems. (From Tor, I think.)
12)	Add a check in ufs_lookup, to avoid lots of unneeded calls to bcmp.
	(experimental.)
13)	Significantly shrink, cleanup, and make slightly faster the vm_fault.c
	code.  Use generation counts, get rid of unneded collpase operations,
	and clean up the cluster code.
14)	Make vm_zone more suitable for TSM.

This commit is partially as a result of discussions and contributions from
other people, including DG, Tor Egge, PHK, and probably others that I
have forgotten to attribute (so let me know, if I forgot.)

This is not the infamous, final cleanup of the vnode stuff, but a necessary
step.  Vnode mgmt should be correct, but things might still change, and
there is still some missing stuff (like ioopt, and physical backing of
non-merged cache files, debugging of layering concepts.)
1998-01-22 17:30:44 +00:00
John Dyson
4722175765 Tie up some loose ends in vnode/object management. Remove an unneeded
config option in pmap.  Fix a problem with faulting in pages.  Clean-up
some loose ends in swap pager memory management.

The system should be much more stable, but all subtile bugs aren't fixed yet.
1998-01-17 09:17:02 +00:00
John Dyson
925a3a419a Fix some vnode management problems, and better mgmt of vnode free list.
Fix the UIO optimization code.
Fix an assumption in vm_map_insert regarding allocation of swap pagers.
Fix an spl problem in the collapse handling in vm_object_deallocate.
When pages are freed from vnode objects, and the criteria for putting
the associated vnode onto the free list is reached, either put the
vnode onto the list, or put it onto an interrupt safe version of the
list, for further transfer onto the actual free list.
Some minor syntax changes changing pre-decs, pre-incs to post versions.
Remove a bogus timeout (that I added for debugging) from vn_lock.

PHK will likely still have problems with the vnode list management, and
so do I, but it is better than it was.
1998-01-12 01:46:33 +00:00
John Dyson
95e5e988e0 Make our v_usecount vnode reference count work identically to the
original BSD code.  The association between the vnode and the vm_object
no longer includes reference counts.  The major difference is that
vm_object's are no longer freed gratuitiously from the vnode, and so
once an object is created for the vnode, it will last as long as the
vnode does.

When a vnode object reference count is incremented, then the underlying
vnode reference count is incremented also.  The two "objects" are now
more intimately related, and so the interactions are now much less
complex.

When vnodes are now normally placed onto the free queue with an object still
attached.  The rundown of the object happens at vnode rundown time, and
happens with exactly the same filesystem semantics of the original VFS
code.  There is absolutely no need for vnode_pager_uncache and other
travesties like that anymore.

A side-effect of these changes is that SMP locking should be much simpler,
the I/O copyin/copyout optimizations work, NFS should be more ponderable,
and further work on layered filesystems should be less frustrating, because
of the totally coherent management of the vnode objects and vnodes.

Please be careful with your system while running this code, but I would
greatly appreciate feedback as soon a reasonably possible.
1998-01-06 05:26:17 +00:00
John Dyson
6d94bea461 Improve my copyright. 1997-12-22 11:54:00 +00:00
John Dyson
f2e6e69d92 Slight performance improvement, removal of unneeded SPLs. 1997-12-07 04:06:41 +00:00
Bruce Evans
1cd52ec333 Don't include <sys/lock.h> in headers when only `struct simplelock' is
required.  Fixed everything that depended on the pollution.
1997-12-05 19:55:52 +00:00
Poul-Henning Kamp
ab3f746966 In all such uses of struct buf: 's/b_un.b_addr/b_data/g' 1997-12-02 21:07:20 +00:00
John Dyson
b4b3edc1f4 Fix a serious problem during resizing buffers where old buffers
address space wasn't being properly reclaimed.
Submitted by:	Bruce Evans <bde@freebsd.org>
1997-12-01 19:04:00 +00:00
John Dyson
4ced7dd5bf Avoid manipulating the buffer map at interrupt time by deferring bfreekva
to getnewbuf, and remove from brelse.
Reviewed by:	dg@root.com
1997-11-24 06:18:27 +00:00
Poul-Henning Kamp
4a11ca4e29 Remove a bunch of variables which were unused both in GENERIC and LINT.
Found by:	-Wunused
1997-11-07 08:53:44 +00:00
Poul-Henning Kamp
cb226aaa62 Move the "retval" (3rd) parameter from all syscall functions and put
it in struct proc instead.

This fixes a boatload of compiler warning, and removes a lot of cruft
from the sources.

I have not removed the /*ARGSUSED*/, they will require some looking at.

libkvm, ps and other userland struct proc frobbing programs will need
recompiled.
1997-11-06 19:29:57 +00:00
Bruce Evans
55b211e3af Removed unused #includes. 1997-10-28 15:59:26 +00:00
Poul-Henning Kamp
dba3870c10 VFS interior redecoration.
Rename vn_default_error to vop_defaultop all over the place.
Move vn_bwrite from vfs_bio.c to vfs_default.c and call it vop_stdbwrite.
Use vop_null instead of nullop.
Move vop_nopoll from vfs_subr.c to vfs_default.c
Move vop_sharedlock from vfs_subr.c to vfs_default.c
Move vop_nolock from vfs_subr.c to vfs_default.c
Move vop_nounlock from vfs_subr.c to vfs_default.c
Move vop_noislocked from vfs_subr.c to vfs_default.c
Use vop_ebadf instead of *_ebadf.
Add vop_defaultop for getpages on master vnode in MFS.
1997-10-26 20:55:39 +00:00
Poul-Henning Kamp
a1c995b626 Last major round (Unless Bruce thinks of somthing :-) of malloc changes.
Distribute all but the most fundamental malloc types.  This time I also
remembered the trick to making things static:  Put "static" in front of
them.

A couple of finer points by:	bde
1997-10-12 20:26:33 +00:00
Poul-Henning Kamp
55166637cd Distribute and statizice a lot of the malloc M_* types.
Substantial input from:	bde
1997-10-11 18:31:40 +00:00
Justin T. Gibbs
ab36c06737 init_main.c subr_autoconf.c:
Add support for "interrupt driven configuration hooks".
	A component of the kernel can register a hook, most likely
	during auto-configuration, and receive a callback once
	interrupt services are available.  This callback will occur before
	the root and dump devices are configured, so the configuration
	task can affect the selection of those two devices or complete
	any tasks that need to be performed prior to launching init.
	System boot is posponed so long as a hook is registered.  The
	hook owner is responsible for removing the hook once their task
	is complete or the system boot can continue.

kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c:
	Change the interface and implementation for the kernel callout
	service.  The new implemntaion is based on the work of
	Adam M. Costello and George Varghese, published in a technical
	report entitled "Redesigning the BSD Callout and Timer Facilities".
	The interface used in FreeBSD is a little different than the one
	outlined in the paper.  The new function prototypes are:

	struct callout_handle timeout(void (*func)(void *),
				      void *arg, int ticks);

	void untimeout(void (*func)(void *), void *arg,
		       struct callout_handle handle);

	If a client wishes to remove a timeout, it must store the
	callout_handle returned by timeout and pass it to untimeout.

	The new implementation gives 0(1) insert and removal of callouts
	making this interface scale well even for applications that
	keep 100s of callouts outstanding.

	See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
John Dyson
804cd17e21 Re-institute a bugfix in allocation of anonymous buffer memory. 1997-09-21 04:49:30 +00:00
Poul-Henning Kamp
c1f95f1378 The patch is needed in order to not throw away unmodified
local filesystem metadata at the first brelse call when the
block device vnode has v_tag set to VT_NFS.

Reviewed by:	phk
Submitted by:	Tor Egge <tegge@idi.ntnu.no>
1997-09-10 20:09:22 +00:00
Bruce Evans
2d85d0df17 Some staticized variables were still declared to be extern. 1997-09-07 16:56:34 +00:00
John Dyson
a5db4bf475 Back out some incorrect changes that was worse than the original bug. 1997-08-26 04:36:27 +00:00
John Dyson
745b842305 Some corrections to the anonymous page managment.
Submitted by:	Peter Chen <pmchen@eecs.umich.edu>
1997-08-21 01:35:37 +00:00
John Dyson
c0ecffb96b Modify the scheduling policy to take into account disk I/O waits
as chargeable CPU usage.  This should mitigate the problem of processes
doing disk I/O hogging the CPU.  Various users have reported the
problem, and test code shows that the problem should now be gone.
1997-08-09 10:13:32 +00:00
John Dyson
6b195d32a1 Fix a problem with the VN device. Specifically, the VN device can
cause a problem of spiraling death due to buffer resource limitations.
The vfs_bio code in general had little ability to handle buffer resource
management, and now it does.  Also, there are a lot more knobs for tuning the
vfs_bio code now.  The knobs came free because of the need that there
always be some immediately available buffers (non-delayed or locked) for
use.  Note that the buffer cache code is much less likely to get bogged
down with lots of delayed writes, even more so than before.
1997-06-15 17:56:53 +00:00
Bruce Evans
bad324ca54 Fixed livelock in getnewbuf().
It is possible for multiple process to sleep concurrently waiting
for a buffer.  When the buffer shortage is a shortage of space but
not a shortage of buffer headers, the processes took turns creating
empty buffers and waking each other to advertise the brelse() of
the empties; progress was never made because tsleep() always found
another high-priority process to run and everything was done at
splbio(), so vfs_update never had a chance to flush delayed writes,
not to mention that i/o never had a chance to complete.

The problem seems to be rare in practice, but it can easily be
reproduced by misusing block devices, at least for sufficently slow
devices on machines with a sufficiently small buffer cache.  E.g.,
`tar cvf /dev/fd0 /kernel' on an 8MB system with no disk in fd0
causes the problem quickly; the same command with a disk in fd0
causes the problem not quite as quickly; and people have reported
problems newfs'ing file systems on block devices.

Block devices only cause this problem indirectly.  They are pessimized
for time and space, and the space pessimization causes the shortage
(it manifests as internal fragmentation in buffer_map).

This should be fixed in 2.2.
1997-06-13 08:30:40 +00:00
Doug Rabson
e90b93a1d0 Don't throw NFS B_DELWRI buffers back to the vm system in brelse.
Make sure that b_validoff..b_validend is at least as big as
b_dirtyoff..b_dirtyend.
1997-06-06 09:04:28 +00:00
Doug Rabson
501338ca4f Fix some performance problems with the NFS mmap fixes. 1997-06-03 09:42:43 +00:00
Doug Rabson
bc3718bb36 The previous fix didn't work properly for small block size filesystems,
which caused very slow file access for cd9660 and some ext2fs filesystems.

Reviewed by:	bde
1997-05-30 22:25:35 +00:00
Doug Rabson
32ad9cb531 Fix a few bugs with NFS and mmap caused by NFS' use of b_validoff
and b_validend.  The changes to vfs_bio.c are a bit ugly but hopefully
can be tidied up later by a slight redesign.

PR:		kern/2573, kern/2754, kern/3046 (possibly)
Reviewed by:	dyson
1997-05-19 14:36:56 +00:00
Joerg Wunsch
8eea4d3c76 Add a DDB command `show buffer', to display a struct buf. It's impossible
to display everything, so i've chosen a small subset.  Add more to this as
you think seems useful.
1997-05-10 09:09:42 +00:00
John Dyson
95395ca1c1 Improve the buffer cache memory policy by moving pages over to the
cache queue more often.  The pageout daemon had to be waken up
more often than necessary since pages were not put on the
cache queue, when they should have been.
Submitted by:	David Greenman <dg@freebsd.org>
1997-04-13 03:33:25 +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
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
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
3596818baa Clean-up of the new buffer kva allocation code. Also, there was an
error in the !BOUNCE_BUFFERS case.
1996-12-05 04:28:52 +00:00
John Dyson
621d520e2f Fix a problem with the new buffer_map management code. Additionally,
decrease the size of buffer_map to approx 2/3 of what it used to be
(buffer_map can be smaller now.)  The original commit of these changes
increased the size of buffer_map to the point where the system would
not boot on large systems -- now large systems with large caches will
have even less problems than before.
1996-12-01 15:46:40 +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
71a5742716 Potentially fix a problem, whereby MSDOSFS can request buffers
larger than the vfs layer can provide.  We now automatically support
32K clusters if MSDOSFS is installed, and panic if a filesystem tries
to allocate a buffer larger than MAXBSIZE.

This commit is a result of some "prodding" by BDE.
1996-11-28 04:26:04 +00:00
John Dyson
9970cd3721 Improve the caching of small files like directories, while not
substantially increasing buffer space.  Specifically, we double
the number of buffers, but allocate only half the amount of memory
per buffer.  Note that VDIR files aren't cached unless instantiated
in a buffer.  This will significantly improve caching.
1996-11-17 02:11:01 +00:00
John Dyson
402bcb9621 Fix a problem that could cause msync (or many other things) to deadlock.
The heuristic for managment of memory backing the buffer cache was
nice, but didn't work due to some architectural problems.  Simplify
and improve the algorithm.
1996-10-17 03:04:43 +00:00
John Dyson
ffe2522e29 Fix 4 problems:
Major: When blocking occurs in allocbuf() for VMIO files,
	       excess wire counts could accumulate.
	Major: Pages are incorrectly accumulated into the physical
	       buffer for clustered reads.  This happens when bogus
	       page is needed.
	Minor: When reclaiming buffers, the async flag on the buffer
	       needs to be zero, or the reclaim is not optimal.
	Minor: The age flag should be cleared, if a buffer is wanted.
1996-10-06 07:50:05 +00:00
John Dyson
08c2c9ddf5 Fix an spl window, a page manipulation at interrupt time that was
incorrect, and correct the support for B_ORDERED.  The spl window
fix was from Peter Wemm, and his questions led me to find the problem with
the interrupt time page manipulation.
1996-09-20 02:26:35 +00:00
John Dyson
f9da2540d2 Add needed spl protection, and some minor cleanups in vfs_vmio_release.
Submitted by:	Peter Wemm <peter@spinner.dialix.com> and me.
1996-09-18 15:57:41 +00:00
John Dyson
8fdfa820e4 Clean up some more problems with freeing busy or wired pages. The
vfs_bio code was not waiting properly for page state until manipulating
it.
1996-09-14 04:40:33 +00:00
John Dyson
9fc1279b79 A modification that allows the driver strategy to modify the
B_ASYNC flag broke things pretty bad (freeing buffer already on
queue or other wierd buffer queue errors.)  The broken code is
left in commented out, but this makes the problem go away for
now.
1996-09-13 03:15:45 +00:00
John Dyson
5070c7f8c5 Addition of page coloring support. Various levels of coloring are afforded.
The default level works with minimal overhead, but one can also enable
full, efficient use of a 512K cache.  (Parameters can be generated
to support arbitrary cache sizes also.)
1996-09-08 20:44:49 +00:00
Justin T. Gibbs
0b64164fca Add bowrite.
Bowrite guarantees that buffers queued after a call to bowrite will
be written after the specified buffer (on a particular device).
Bowrite does this either by taking advantage of hardware ordering support
(e.g. tagged queueing on SCSI devices) or resorting to a synchronous write.
1996-09-06 05:37:53 +00:00
John Dyson
6476c0d204 Even though this looks like it, this is not a complex code change.
The interface into the "VMIO" system has changed to be more consistant
and robust.  Essentially, it is now no longer necessary to call vn_open
to get merged VM/Buffer cache operation, and exceptional conditions
such as merged operation of VBLK devices is simpler and more correct.

This code corrects a potentially large set of problems including the
problems with ktrace output and loaded systems, file create/deletes,
etc.

Most of the changes to NFS are cosmetic and name changes, eliminating
a layer of subroutine calls.  The direct calls to vput/vrele have
been re-instituted for better cross platform compatibility.

Reviewed by: davidg
1996-08-21 21:56:23 +00:00
Poul-Henning Kamp
d1c4c866f0 Add separate kmalloc classes for BIO buffers and Ktrace info. 1996-08-04 20:13:08 +00:00