Commit Graph

83 Commits

Author SHA1 Message Date
Alan Cox
c2eda4b565 o Remove some long dead code: from revision 1.41 of vm/vm_pager.c
3+ years ago.
 o Remove some unused prototypes.
2002-07-01 02:38:05 +00:00
Alan Cox
7942194583 o Remove GIANT_REQUIRED from vm_pager_allocate() and vm_pager_deallocate(). 2002-06-21 05:04:56 +00:00
John Baldwin
6008862bc2 Change callers of mtx_init() to pass in an appropriate lock type name. In
most cases NULL is passed, but in some cases such as network driver locks
(which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used.

Tested on:	i386, alpha, sparc64
2002-04-04 21:03:38 +00:00
Alfred Perlstein
11caded34f Remove __P. 2002-03-19 22:20:14 +00:00
Jake Burkholder
ac59490b5e Convert all pmap_kenter/pmap_kremove pairs in MI code to use pmap_qenter/
pmap_qremove.  pmap_kenter is not safe to use in MI code because it is not
guaranteed to flush the mapping from the tlb on all cpus.  If the process
in question is preempted and migrates cpus between the call to pmap_kenter
and pmap_kremove, the original cpu will be left with stale mappings in its
tlb.  This is currently not a problem for i386 because we do not use PG_G on
SMP, and thus all mappings are flushed from the tlb on context switches, not
just user mappings.  This is not the case on all architectures, and if PG_G
is to be used with SMP on i386 it will be a problem.  This was committed by
peter earlier as part of his fine grained tlb shootdown work for i386, which
was backed out for other reasons.

Reviewed by:	peter
2002-03-17 00:56:41 +00:00
Eivind Eklund
a128794977 - Remove a number of extra newlines that do not belong here according to
style(9)
- Minor space adjustment in cases where we have "( ", " )", if(), return(),
  while(), for(), etc.
- Add /* SYMBOL */ after a few #endifs.

Reviewed by:	alc
2002-03-10 21:52:48 +00:00
Eivind Eklund
f52bd684f3 * Move bswlist declaration and initialization from kern/vfs_bio.c to
vm/vm_pager.c, which is the only place it is used.
* Make the QUEUE_* definitions and bufqueues local to vfs_bio.c.
* constify buf_wmesg.
2002-03-05 18:20:58 +00:00
Peter Wemm
d1693e1701 Back out all the pmap related stuff I've touched over the last few days.
There is some unresolved badness that has been eluding me, particularly
affecting uniprocessor kernels.  Turning off PG_G helped (which is a bad
sign) but didn't solve it entirely.  Userland programs still crashed.
2002-02-27 09:51:33 +00:00
Peter Wemm
bd1e3a0f89 Jake further reduced IPI shootdowns on sparc64 in loops by using ranged
shootdowns in a couple of key places.  Do the same for i386.  This also
hides some physical addresses from higher levels and has it use the
generic vm_page_t's instead.  This will help for PAE down the road.

Obtained from:	jake (MI code, suggestions for MD part)
2002-02-27 02:14:58 +00:00
John Baldwin
bd8e0d5871 Whitespace fixes. 2001-08-04 20:49:29 +00:00
Matthew Dillon
54d9214595 whitespace / register cleanup 2001-07-04 19:00:13 +00:00
Matthew Dillon
0cddd8f023 With Alfred's permission, remove vm_mtx in favor of a fine-grained approach
(this commit is just the first stage).  Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
2001-07-04 16:20:28 +00:00
Alfred Perlstein
2395531439 Introduce a global lock for the vm subsystem (vm_mtx).
vm_mtx does not recurse and is required for most low level
vm operations.

faults can not be taken without holding Giant.

Memory subsystems can now call the base page allocators safely.

Almost all atomic ops were removed as they are covered under the
vm mutex.

Alpha and ia64 now need to catch up to i386's trap handlers.

FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).

Reviewed (partially) by: jake, jhb
2001-05-19 01:28:09 +00:00
Poul-Henning Kamp
f84e29a06c This patch removes the VOP_BWRITE() vector.
VOP_BWRITE() was a hack which made it possible for NFS client
side to use struct buf with non-bio backing.

This patch takes a more general approach and adds a bp->b_op
vector where more methods can be added.

The success of this patch depends on bp->b_op being initialized
all relevant places for some value of "relevant" which is not
easy to determine.  For now the buffers have grown a b_magic
element which will make such issues a tiny bit easier to debug.
2001-04-17 08:56:39 +00:00
Alfred Perlstein
2a758ebe58 protect pbufs and associated counts with a mutex 2001-04-13 10:23:32 +00:00
Poul-Henning Kamp
fc2ffbe604 Mechanical change to use <sys/queue.h> macro API instead of
fondling implementation details.

Created with: sed(1)
Reviewed by: md5(1)
2001-02-04 13:13:25 +00:00
Bruce Evans
03b67a395f Backed out previous commit. Don't depend on namespace pollution in
<sys/buf.h>.
2000-12-02 12:03:58 +00:00
Alfred Perlstein
82625cf321 remove unneded sys/ucred.h includes 2000-11-30 18:52:32 +00:00
Poul-Henning Kamp
9f69a4578a Weaken a bogus dependency on <sys/proc.h> in <sys/buf.h> by #ifdef'ing
the offending inline function (BUF_KERNPROC) on it being #included
already.

I'm not sure BUF_KERNPROC() is even the right thing to do or in the
right place or implemented the right way (inline vs normal function).

Remove consequently unneeded #includes of <sys/proc.h>
2000-10-29 14:54:55 +00:00
Peter Wemm
249645144d Checkpoint of a new physical memory backed object type, that does not
have pv_entries.  This is intended for very special circumstances,
eg: a certain database that has a 1GB shm segment mapped into 300
processes.  That would consume 2GB of kvm just to hold the pv_entries
alone.  This would not be used on systems unless the physical ram was
available, as it's not pageable.

This is a work-in-progress, but is a useful and functional checkpoint.
Matt has got some more fixes for it that will be committed soon.

Reviewed by:	dillon
2000-05-21 13:41:29 +00:00
Poul-Henning Kamp
9626b608de Separate the struct bio related stuff out of <sys/buf.h> into
<sys/bio.h>.

<sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall
not be made a nested include according to bdes teachings on the
subject of nested includes.

Diskdrivers and similar stuff below specfs::strategy() should no
longer need to include <sys/buf.> unless they need caching of data.

Still a few bogus uses of struct buf to track down.

Repocopy by:    peter
2000-05-05 09:59:14 +00:00
Poul-Henning Kamp
0b441832f3 Convert the vm_pager_strategy() interface to take a struct bio instead of
a struct buf.  Don't try to examine B_ASYNC, it is a layering violation
to do so.  The only current user of this interface is vn(4) which, since
it emulates a disk interface, operates on struct bio already.
2000-05-03 07:47:46 +00:00
Poul-Henning Kamp
e4057dbdb0 Move and staticize the bufchain functions so they become local to the
only piece of code using them.  This will ease a rewrite of them.
2000-05-01 19:38:51 +00:00
Poul-Henning Kamp
8177437d85 Complete the bio/buf divorce for all code below devfs::strategy
Exceptions:
        Vinum untouched.  This means that it cannot be compiled.
        Greg Lehey is on the case.

        CCD not converted yet, casts to struct buf (still safe)

        atapi-cd casts to struct buf to examine B_PHYS
2000-04-15 05:54:02 +00:00
Poul-Henning Kamp
c244d2de43 Move B_ERROR flag to b_ioflags and call it BIO_ERROR.
(Much of this done by script)

Move B_ORDERED flag to b_ioflags and call it BIO_ORDERED.

Move b_pblkno and b_iodone_chain to struct bio while we transition, they
will be obsoleted once bio structs chain/stack.

Add bio_queue field for struct bio aware disksort.

Address a lot of stylistic issues brought up by bde.
2000-04-02 15:24:56 +00:00
Philippe Charnier
5929bcfaba Revert spelling mistake I made in the previous commit
Requested by: Alan and Bruce
2000-03-27 20:41:17 +00:00
Philippe Charnier
956f31353c Spelling 2000-03-26 15:20:23 +00:00
Poul-Henning Kamp
b99c307a21 Rename the existing BUF_STRATEGY() to DEV_STRATEGY()
substitute BUF_WRITE(foo) for VOP_BWRITE(foo->b_vp, foo)

substitute BUF_STRATEGY(foo) for VOP_STRATEGY(foo->b_vp, foo)

This patch is machine generated except for the ccd.c and buf.h parts.
2000-03-20 11:29:10 +00:00
Poul-Henning Kamp
21144e3bf1 Remove B_READ, B_WRITE and B_FREEBUF and replace them with a new
field in struct buf: b_iocmd.  The b_iocmd is enforced to have
exactly one bit set.

B_WRITE was bogusly defined as zero giving rise to obvious coding
mistakes.

Also eliminate the redundant struct buf flag B_CALL, it can just
as efficiently be done by comparing b_iodone to NULL.

Should you get a panic or drop into the debugger, complaining about
"b_iocmd", don't continue.  It is likely to write on your disk
where it should have been reading.

This change is a step in the direction towards a stackable BIO capability.

A lot of this patch were machine generated (Thanks to style(9) compliance!)

Vinum users:  Greg has not had time to test this yet, be careful.
2000-03-20 10:44:49 +00:00
Poul-Henning Kamp
923502ff91 useracc() the prequel:
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>.  This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.

This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
1999-10-29 18:09:36 +00:00
Matthew Dillon
2eab8b3609 Add required BUF_KERNPROC to flushchainbuf() to disassociate the
current process from the exclusive lock prior to initiating I/O.

    This fixes a panic related to swap-backed VN disks

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:03:27 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Stephen McKay
652fcae07c Reformat previous fix to remove an uglier than average goto.
Looked OK to:	dg
1999-07-05 12:50:54 +00:00
Kirk McKusick
e929c00d23 The buffer queue mechanism has been reformulated. Instead of having
QUEUE_AGE, QUEUE_LRU, and QUEUE_EMPTY we instead have QUEUE_CLEAN,
QUEUE_DIRTY, QUEUE_EMPTY, and QUEUE_EMPTYKVA.  With this patch clean
and dirty buffers have been separated.  Empty buffers with KVM
assignments have been separated from truely empty buffers.  getnewbuf()
has been rewritten and now operates in a 100% optimal fashion.  That is,
it is able to find precisely the right kind of buffer it needs to
allocate a new buffer, defragment KVM, or to free-up an existing buffer
when the buffer cache is full (which is a steady-state situation for
the buffer cache).

Buffer flushing has been reorganized.  Previously buffers were flushed
in the context of whatever process hit the conditions forcing buffer
flushing to occur.  This resulted in processes blocking on conditions
unrelated to what they were doing.  This also resulted in inappropriate
VFS stacking chains due to multiple processes getting stuck trying to
flush dirty buffers or due to a single process getting into a situation
where it might attempt to flush buffers recursively - a situation that
was only partially fixed in prior commits.  We have added a new daemon
called the buf_daemon which is responsible for flushing dirty buffers
when the number of dirty buffers exceeds the vfs.hidirtybuffers limit.
This daemon attempts to dynamically adjust the rate at which dirty buffers
are flushed such that getnewbuf() calls (almost) never block.

The number of nbufs and amount of buffer space is now scaled past the
8MB limit that was previously imposed for systems with over 64MB of
memory, and the vfs.{lo,hi}dirtybuffers limits have been relaxed
somewhat.  The number of physical buffers has been increased with the
intention that we will manage physical I/O differently in the future.

reassignbuf previously attempted to keep the dirtyblkhd list sorted which
could result in non-deterministic operation under certain conditions,
such as when a large number of dirty buffers are being managed.  This
algorithm has been changed.  reassignbuf now keeps buffers locally sorted
if it can do so cheaply, and otherwise gives up and adds buffers to
the head of the dirtyblkhd list.  The new algorithm is deterministic but
not perfect.  The new algorithm greatly reduces problems that previously
occured when write_behind was turned off in the system.

The P_FLSINPROG proc->p_flag bit has been replaced by the more descriptive
P_BUFEXHAUST bit.  This bit allows processes working with filesystem
buffers to use available emergency reserves.  Normal processes do not set
this bit and are not allowed to dig into emergency reserves.  The purpose
of this bit is to avoid low-memory deadlocks.

A small race condition was fixed in getpbuf() in vm/vm_pager.c.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by:	Kirk McKusick <mckusick@mckusick.com>
1999-07-04 00:25:38 +00:00
Peter Wemm
e96c1fdc3f Minor tweaks to make sure (new) prerequisites for <sys/buf.h> (mostly
splbio()/splx()) are #included in time.
1999-06-27 11:44:22 +00:00
Kirk McKusick
67812eacd7 Convert buffer locking from using the B_BUSY and B_WANTED flags to using
lockmgr locks. This commit should be functionally equivalent to the old
semantics. That is, all buffer locking is done with LK_EXCLUSIVE
requests. Changes to take advantage of LK_SHARED and LK_RECURSIVE will
be done in future commits.
1999-06-26 02:47:16 +00:00
Poul-Henning Kamp
b0eeea2042 remove b_proc from struct buf, it's (now) unused.
Reviewed by:	dillon, bde
1999-05-06 20:00:34 +00:00
Alan Cox
4221e284a3 The VFS/BIO subsystem contained a number of hacks in order to optimize
piecemeal, middle-of-file writes for NFS.  These hacks have caused no
end of trouble, especially when combined with mmap().  I've removed
them.  Instead, NFS will issue a read-before-write to fully
instantiate the struct buf containing the write.  NFS does, however,
optimize piecemeal appends to files.  For most common file operations,
you will not notice the difference.  The sole remaining fragment in
the VFS/BIO system is b_dirtyoff/end, which NFS uses to avoid cache
coherency issues with read-merge-write style operations.  NFS also
optimizes the write-covers-entire-buffer case by avoiding the
read-before-write.  There is quite a bit of room for further
optimization in these areas.

The VM system marks pages fully-valid (AKA vm_page_t->valid =
VM_PAGE_BITS_ALL) in several places, most noteably in vm_fault.  This
is not correct operation.  The vm_pager_get_pages() code is now
responsible for marking VM pages all-valid.  A number of VM helper
routines have been added to aid in zeroing-out the invalid portions of
a VM page prior to the page being marked all-valid.  This operation is
necessary to properly support mmap().  The zeroing occurs most often
when dealing with file-EOF situations.  Several bugs have been fixed
in the NFS subsystem, including bits handling file and directory EOF
situations and buf->b_flags consistancy issues relating to clearing
B_ERROR & B_INVAL, and handling B_DONE.

getblk() and allocbuf() have been rewritten.  B_CACHE operation is now
formally defined in comments and more straightforward in
implementation.  B_CACHE for VMIO buffers is based on the validity of
the backing store.  B_CACHE for non-VMIO buffers is based simply on
whether the buffer is B_INVAL or not (B_CACHE set if B_INVAL clear,
and vise-versa).  biodone() is now responsible for setting B_CACHE
when a successful read completes.  B_CACHE is also set when a bdwrite()
is initiated and when a bwrite() is initiated.  VFS VOP_BWRITE
routines (there are only two - nfs_bwrite() and bwrite()) are now
expected to set B_CACHE.  This means that bowrite() and bawrite() also
set B_CACHE indirectly.

There are a number of places in the code which were previously using
buf->b_bufsize (which is DEV_BSIZE aligned) when they should have
been using buf->b_bcount.  These have been fixed.  getblk() now clears
B_DONE on return because the rest of the system is so bad about
dealing with B_DONE.

Major fixes to NFS/TCP have been made.  A server-side bug could cause
requests to be lost by the server due to nfs_realign() overwriting
other rpc's in the same TCP mbuf chain.  The server's kernel must be
recompiled to get the benefit of the fixes.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
1999-05-02 23:57:16 +00:00
Eivind Eklund
0776e10c71 Staticize 1999-04-11 02:16:27 +00:00
Julian Elischer
a5296b05b4 Submitted by: Matt Dillon <dillon@freebsd.org>
The old VN device broke in -4.x when the definition of B_PAGING
changed. This patch fixes this plus implements additional capabilities.
The new VN device can be backed by a file ( as per normal ), or it can
be directly backed by swap.

Due to dependencies in VM include files  (on opt_xxx options) the new
vn device cannot be a module yet. This will be fixed in a later commit.
This commit delimitted by tags {PRE,POST}_MATT_VNDEV
1999-03-14 09:20:01 +00:00
Matthew Dillon
e4542174b0 vm_pager_put_pages() is passed an rcval array to hold per-page return
values.  The 'int' return value for the procedure was never used and
    not well defined in any case when there are mixed errors on pages, so
    it has been removed.  vm_pager_put_pages() and associated vm_pager
    functions now return void.
1999-01-24 02:32:15 +00:00
Matthew Dillon
f85f2fa903 Move many of the vm_pager_*() functions from vm_pager.c to inlines in
vm_pager.h

     Added argument to getpbuf() and relpbuf() to allow each subsystem to
     specify a different hard limit on the number of simultanious physical
     bufferes that said subsystem may allocate.  Without this feature, one
     subsystem ( e.g. the vfs clustering code ) could hog *ALL* the pbufs,
     causing a deadlock in the pager in a low memory situation.

     Same for trypbuf().
1999-01-21 10:15:24 +00:00
Matthew Dillon
1c7c3c6a86 This is a rather large commit that encompasses the new swapper,
changes to the VM system to support the new swapper, VM bug
    fixes, several VM optimizations, and some additional revamping of the
    VM code.  The specific bug fixes will be documented with additional
    forced commits.  This commit is somewhat rough in regards to code
    cleanup issues.

Reviewed by:	"John S. Dyson" <root@dyson.iquest.net>, "David Greenman" <dg@root.com>
1999-01-21 08:29:12 +00:00
Peter Wemm
1c5bb3eaa1 add #include <sys/kernel.h> where it's needed by MALLOC_DEFINE() 1998-11-10 09:16:29 +00:00
Peter Wemm
40c8cfe552 Use TAILQ macros for clean/dirty block list processing. Set b_xflags
rather than abusing the list next pointer with a magic number.
1998-10-31 15:31:29 +00:00
David Greenman
6cde7a165f Fixed two potentially serious classes of bugs:
1) The vnode pager wasn't properly tracking the file size due to
   "size" being page rounded in some cases and not in others.
   This sometimes resulted in corrupted files. First noticed by
   Terry Lambert.
   Fixed by changing the "size" pager_alloc parameter to be a 64bit
   byte value (as opposed to a 32bit page index) and changing the
   pagers and their callers to deal with this properly.
2) Fixed a bogus type cast in round_page() and trunc_page() that
   caused some 64bit offsets and sizes to be scrambled. Removing
   the cast required adding casts at a few dozen callers.
   There may be problems with other bogus casts in close-by
   macros. A quick check seemed to indicate that those were okay,
   however.
1998-10-13 08:24:45 +00:00
John Dyson
bef608bd7e Some VM improvements, including elimination of alot of Sig-11
problems.  Tor Egge and others have helped with various VM bugs
lately, but don't blame him -- blame me!!!

pmap.c:
1)	Create an object for kernel page table allocations.  This
	fixes a bogus allocation method previously used for such, by
	grabbing pages from the kernel object, using bogus pindexes.
	(This was a code cleanup, and perhaps a minor system stability
	 issue.)

pmap.c:
2)	Pre-set the modify and accessed bits when prudent.  This will
	decrease bus traffic under certain circumstances.

vfs_bio.c, vfs_cluster.c:
3)	Rather than calculating the beginning virtual byte offset
	multiple times, stick the offset into the buffer header, so
	that the calculated offset can be reused.  (Long long multiplies
	are often expensive, and this is a probably unmeasurable performance
	improvement, and code cleanup.)

vfs_bio.c:
4)	Handle write recursion more intelligently (but not perfectly) so
	that it is less likely to cause a system panic, and is also
	much more robust.

vfs_bio.c:
5)	getblk incorrectly wrote out blocks that are incorrectly sized.
	The problem is fixed, and writes blocks out ONLY when B_DELWRI
	is true.

vfs_bio.c:
6)	Check that already constituted buffers have fully valid pages.  If
	not, then make sure that the B_CACHE bit is not set. (This was
	a major source of Sig-11 type problems.)

vfs_bio.c:
7)	Fix a potential system deadlock due to an incorrectly specified
	sleep priority while waiting for a buffer write operation.  The
	change that I made opens the system up to serious problems, and
	we need to examine the issue of process sleep priorities.

vfs_cluster.c, vfs_bio.c:
8)	Make clustered reads work more correctly (and more completely)
	when buffers are already constituted, but not fully valid.
	(This was another system reliability issue.)

vfs_subr.c, ffs_inode.c:
9)	Create a vtruncbuf function, which is used by filesystems that
	can truncate files.  The vinvalbuf forced a file sync type operation,
	while vtruncbuf only invalidates the buffers past the new end of file,
	and also invalidates the appropriate pages.  (This was a system reliabiliy
	and performance issue.)

10)	Modify FFS to use vtruncbuf.

vm_object.c:
11)	Make the object rundown mechanism for OBJT_VNODE type objects work
	more correctly.  Included in that fix, create pager entries for
	the OBJT_DEAD pager type, so that paging requests that might slip
	in during race conditions are properly handled.  (This was a system
	reliability issue.)

vm_page.c:
12)	Make some of the page validation routines be a little less picky
	about arguments passed to them.  Also, support page invalidation
	change the object generation count so that we handle generation
	counts a little more robustly.

vm_pageout.c:
13)	Further reduce pageout daemon activity when the system doesn't
	need help from it.  There should be no additional performance
	decrease even when the pageout daemon is running.  (This was
	a significant performance issue.)

vnode_pager.c:
14)	Teach the vnode pager to handle race conditions during vnode
	deallocations.
1998-03-16 01:56:03 +00:00
John Dyson
8f9110f6a1 This mega-commit is meant to fix numerous interrelated problems. There
has been some bitrot and incorrect assumptions in the vfs_bio code.  These
problems have manifest themselves worse on NFS type filesystems, but can
still affect local filesystems under certain circumstances.  Most of
the problems have involved mmap consistancy, and as a side-effect broke
the vfs.ioopt code.  This code might have been committed seperately, but
almost everything is interrelated.

1)	Allow (pmap_object_init_pt) prefaulting of buffer-busy pages that
	are fully valid.
2)	Rather than deactivating erroneously read initial (header) pages in
	kern_exec, we now free them.
3)	Fix the rundown of non-VMIO buffers that are in an inconsistent
	(missing vp) state.
4)	Fix the disassociation of pages from buffers in brelse.  The previous
	code had rotted and was faulty in a couple of important circumstances.
5)	Remove a gratuitious buffer wakeup in vfs_vmio_release.
6)	Remove a crufty and currently unused cluster mechanism for VBLK
	files in vfs_bio_awrite.  When the code is functional, I'll add back
	a cleaner version.
7)	The page busy count wakeups assocated with the buffer cache usage were
	incorrectly cleaned up in a previous commit by me.  Revert to the
	original, correct version, but with a cleaner implementation.
8)	The cluster read code now tries to keep data associated with buffers
	more aggressively (without breaking the heuristics) when it is presumed
	that the read data (buffers) will be soon needed.
9)	Change to filesystem lockmgr locks so that they use LK_NOPAUSE.  The
	delay loop waiting is not useful for filesystem locks, due to the
	length of the time intervals.
10)	Correct and clean-up spec_getpages.
11)	Implement a fully functional nfs_getpages, nfs_putpages.
12)	Fix nfs_write so that modifications are coherent with the NFS data on
	the server disk (at least as well as NFS seems to allow.)
13)	Properly support MS_INVALIDATE on NFS.
14)	Properly pass down MS_INVALIDATE to lower levels of the VM code from
	vm_map_clean.
15)	Better support the notion of pages being busy but valid, so that
	fewer in-transit waits occur.  (use p->busy more for pageouts instead
	of PG_BUSY.)  Since the page is fully valid, it is still usable for
	reads.
16)	It is possible (in error) for cached pages to be busy.  Make the
	page allocation code handle that case correctly.  (It should probably
	be a printf or panic, but I want the system to handle coding errors
	robustly.  I'll probably add a printf.)
17)	Correct the design and usage of vm_page_sleep.  It didn't handle
	consistancy problems very well, so make the design a little less
	lofty.  After vm_page_sleep, if it ever blocked, it is still important
	to relookup the page (if the object generation count changed), and
	verify it's status (always.)
18)	In vm_pageout.c, vm_pageout_clean had rotted, so clean that up.
19)	Push the page busy for writes and VM_PROT_READ into vm_pageout_flush.
20)	Fix vm_pager_put_pages and it's descendents to support an int flag
	instead of a boolean, so that we can pass down the invalidate bit.
1998-03-07 21:37:31 +00:00
John Dyson
e47ed70b0f Significantly improve the efficiency of the swap pager, which appears to
have declined due to code-rot over time.  The swap pager rundown code
has been clean-up, and unneeded wakeups removed.  Lots of splbio's
are changed to splvm's.  Also, set the dynamic tunables for the
pageout daemon to be more sane for larger systems (thereby decreasing
the daemon overheadla.)
1998-02-23 08:22:48 +00:00
Eivind Eklund
0b08f5f737 Back out DIAGNOSTIC changes. 1998-02-06 12:14:30 +00:00