Commit Graph

1075 Commits

Author SHA1 Message Date
John Baldwin
c86b6ff551 Change the preemption code for software interrupt thread schedules and
mutex releases to not require flags for the cases when preemption is
not allowed:

The purpose of the MTX_NOSWITCH and SWI_NOSWITCH flags is to prevent
switching to a higher priority thread on mutex releease and swi schedule,
respectively when that switch is not safe.  Now that the critical section
API maintains a per-thread nesting count, the kernel can easily check
whether or not it should switch without relying on flags from the
programmer.  This fixes a few bugs in that all current callers of
swi_sched() used SWI_NOSWITCH, when in fact, only the ones called from
fast interrupt handlers and the swi_sched of softclock needed this flag.
Note that to ensure that swi_sched()'s in clock and fast interrupt
handlers do not switch, these handlers have to be explicitly wrapped
in critical_enter/exit pairs.  Presently, just wrapping the handlers is
sufficient, but in the future with the fully preemptive kernel, the
interrupt must be EOI'd before critical_exit() is called.  (critical_exit()
can switch due to a deferred preemption in a fully preemptive kernel.)

I've tested the changes to the interrupt code on i386 and alpha.  I have
not tested ia64, but the interrupt code is almost identical to the alpha
code, so I expect it will work fine.  PowerPC and ARM do not yet have
interrupt code in the tree so they shouldn't be broken.  Sparc64 is
broken, but that's been ok'd by jake and tmm who will be fixing the
interrupt code for sparc64 shortly.

Reviewed by:	peter
Tested on:	i386, alpha
2002-01-05 08:47:13 +00:00
Matthew Dillon
23b590188f Fix a BUF_TIMELOCK race against BUF_LOCK and fix a deadlock in vget()
against VM_WAIT in the pageout code.  Both fixes involve adjusting
the lockmgr's timeout capability so locks obtained with timeouts do not
interfere with locks obtained without a timeout.

Hopefully MFC: before the 4.5 release
2001-12-20 22:42:27 +00:00
Matthew Dillon
3ebeaf5984 This fixes a large number of bugs in our NFS client side code. A recent
commit by Kirk also fixed a softupdates bug that could easily be triggered
by server side NFS.

	* An edge case with shared R+W mmap()'s and truncate whereby
	  the system would inappropriately clear the dirty bits on
	  still-dirty data.  (applicable to all filesystems)

	  THIS FIX TEMPORARILY DISABLED PENDING FURTHER TESTING.
	  see vm/vm_page.c line 1641

	* The straddle case for VM pages and buffer cache buffers when
	  truncating.  (applicable to NFS client side)

	* Possible SMP database corruption due to vm_pager_unmap_page()
	  not clearing the TLB for the other cpu's.  (applicable to NFS
	  client side but could effect all filesystems).  Note: not
	  considered serious since the corruption occurs beyond the file
	  EOF.

	* When flusing a dirty buffer due to B_CACHE getting cleared,
	  we were accidently setting B_CACHE again (that is, bwrite() sets
	  B_CACHE), when we really want it to stay clear after the write
	  is complete.  This resulted in a corrupt buffer.  (applicable
	  to all filesystems but probably only triggered by NFS)

	* We have to call vtruncbuf() when ftruncate()ing to remove
	  any buffer cache buffers.  This is still tentitive, I may
	  be able to remove it due to the second bug fix.  (applicable
	  to NFS client side)

	* vnode_pager_setsize() race against nfs_vinvalbuf()... we have
	  to set n_size before calling nfs_vinvalbuf or the NFS code
	  may recursively vnode_pager_setsize() to the original value
	  before the truncate.  This is what was causing the user mmap
	  bus faults in the nfs tester program.  (applicable to NFS
	  client side)

	* Fix to softupdates (see ufs/ffs/ffs_inode.c 1.73, commit made
	  by Kirk).

Testing program written by: Avadis Tevanian, Jr.
Testing program supplied by: jkh / Apple (see Dec2001 posting to freebsd-hackers with Subject 'NFS: How to make FreeBS fall on its face in one easy step')
MFC after:	1 week
2001-12-14 01:16:57 +00:00
Luigi Rizzo
60363fb9f7 vm/vm_kern.c: rate limit (to once per second) diagnostic printf when
you run out of mbuf address space.

kern/subr_mbuf.c: print a warning message when mb_alloc fails, again
	rate-limited to at most once per second. This covers other
	cases of mbuf allocation failures. Probably it also overlaps the
	one handled in vm/vm_kern.c, so maybe the latter should go away.

This warning will let us gradually remove the printf that are scattered
across most network drivers to report mbuf allocation failures.
Those are potentially dangerous, in that they are not rate-limited and
can easily cause systems to panic.

Unless there is disagreement (which does not seem to be the case
judging from the discussion on -net so far), and because this is
sort of a safety bugfix, I plan to commit a similar change to STABLE
during the weekend (it affects kern/uipc_mbuf.c there).

Discussed-with: jlemon, silby and -net
2001-12-01 00:21:30 +00:00
Jonathan Lemon
4584bbf555 When laying out objects in a ZONE_INTERRUPT zone, allow them to cross
a page boundary, since we've already allocated all our contiguous kva
space up front.  This eliminates some memory wastage, and allows us to
actually reach the # of objects were specified in the zinit() call.

Reviewed by: peter, dillon
2001-11-17 00:40:48 +00:00
Matthew Dillon
fe8e0238cc Fix deadlock introduced in 1.73 (Jan 1998). The paging-in-progress count
on a vnode-backed object must be incremented *after* obtaining the vnode
lock.  If it is bumped before obtaining the vnode lock we can deadlock
against vtruncbuf().

Submitted by:	peter, ps
MFC after:	3 days
2001-11-09 21:34:45 +00:00
Matthew Dillon
33c6774151 Adjust vnode_pager_input_smlfs() to not attempt to BMAP blocks beyond the
file EOF.  This works around a bug in the ISOFS (CDRom) BMAP code which
returns bogus values for requests beyond the file EOF rather then returning
an error, resulting in either corrupt data being mmap()'d beyond the file EOF
or resulting in a seg-fault on the last page of a mmap()'d file (mmap()s of
CDRom files).

Reported by: peter / Yahoo
MFC after:	3 days
2001-11-05 18:58:47 +00:00
Matthew Dillon
e302698320 Don't let pmap_object_init_pt() exhaust all available free pages
(allocating pv entries w/ zalloci) when called in a loop due to
an madvise().  It is possible to completely exhaust the free page list and
cause a system panic when an expected allocation fails.
2001-10-31 03:06:33 +00:00
Matthew Dillon
7a5a635273 Move recently added procedure which was incorrectly placed within an
#ifdef DDB block.
2001-10-26 16:27:54 +00:00
Matthew Dillon
245df27cee Implement kern.maxvnodes. adjusting kern.maxvnodes now actually has a
real effect.

Optimize vfs_msync().  Avoid having to continually drop and re-obtain
mutexes when scanning the vnode list.  Improves looping case by 500%.

Optimize ffs_sync().  Avoid having to continually drop and re-obtain
mutexes when scanning the vnode list.  This makes a couple of assumptions,
which I believe are ok, in regards to vnode stability when the mount list
mutex is held.  Improves looping case by 500%.

(more optimization work is needed on top of these fixes)

MFC after:	1 week
2001-10-26 00:08:05 +00:00
Matthew Dillon
57601bcb5d Syntax cleanup and documentation, no operational changes.
MFC after:	1 day
2001-10-21 06:12:06 +00:00
Ian Dowse
0eb6ce3169 Move the code that computes the system load average from vm_meter.c
to kern_synch.c in preparation for adding some jitter to the
inter-sample time.

Note that the "vm.loadavg" sysctl still lives in vm_meter.c which
isn't the right place, but it is appropriate for the current (bad)
name of that sysctl.

Suggested by:	jhb (some time ago)
Reviewed by:	bde
2001-10-20 13:10:43 +00:00
Matthew Dillon
b386828956 contigmalloc1() could cause the vm_page_zero_count to become incorrect.
Properly track the count.

Submitted by:	mark tinguely <tinguely@web.cs.ndsu.nodak.edu>
2001-10-17 17:34:34 +00:00
Tor Egge
d6844b6bf6 Don't use an uninitialized field reserved for callers in the bio structure
passed to swap_pager_strategy().  Instead, use a field reserved for drivers
and initialize it before usage.

Reviewed by:	dillon
2001-10-15 23:02:54 +00:00
Tor Egge
30105b9ec4 Don't remove all mappings of a swapped out process if the vm map contained
wired entries.  vm_fault_unwire() depends on the mapping being intact.

Reviewed by:	dillon
2001-10-14 20:51:14 +00:00
Tor Egge
e7673b8424 Fix locking violations during page wiring:
- vm map entries are not valid after the map has been unlocked.

 - An exclusive lock on the map is needed before calling
   vm_map_simplify_entry().

Fix cleanup after page wiring failure to unwire all pages that had been
successfully wired before the failure was detected.

Reviewed by:	dillon
2001-10-14 20:47:08 +00:00
Matthew Dillon
33bd457d91 Makes contigalloc[1]() create the vm_map / underlying wired pages in the
kernel map and object in a manner that contigfree() is actually able to
free.  Previously contigfree() freed up the KVA space but could not
unwire & free the underlying VM pages due to mismatched pageability between
the map entry and the VM pages.

Submitted by:	Thomas Moestl <tmoestl@gmx.net>
Testing by: mark tinguely <tinguely@web.cs.ndsu.nodak.edu>
MFC after:	3 days
2001-10-13 04:23:37 +00:00
Matthew Dillon
00a6f47f13 Finally fix the VM bug where a file whos EOF occurs in the middle of a page
would sometimes prevent a dirty page from being cleaned, even when synced,
resulting in the dirty page being re-flushed to disk every 30-60 seconds or
so, forever.  The problem is that when the filesystem flushes a page to
its backing file it typically does not clear dirty bits representing areas
of the page that are beyond the file EOF.  If the file is also mmap()'d and
a fault is taken, vm_fault (properly, is required to) set the vm_page_t->dirty
bits to VM_PAGE_BITS_ALL.  This combination could leave us with an uncleanable,
unfreeable page.

The solution is to have the vnode_pager detect the edge case and manually
clear the dirty bits representing areas beyond the file EOF.  The filesystem
does the rest and the page comes up clean after the write completes.

MFC after:	3 days
2001-10-12 18:17:34 +00:00
John Baldwin
bd78cece5d Change the kernel's ucred API as follows:
- crhold() returns a reference to the ucred whose refcount it bumps.
- crcopy() now simply copies the credentials from one credential to
  another and has no return value.
- a new crshared() primitive is added which returns true if a ucred's
  refcount is > 1 and false (0) otherwise.
2001-10-11 23:38:17 +00:00
John Baldwin
61d80e90a9 Add missing includes of sys/ktr.h. 2001-10-11 17:53:43 +00:00
Paul Saab
cbc89bfbfe Make MAXTSIZ, DFLDSIZ, MAXDSIZ, DFLSSIZ, MAXSSIZ, SGROWSIZ loader
tunable.

Reviewed by:	peter
MFC after:	2 weeks
2001-10-10 23:06:54 +00:00
Ian Dowse
564bfabecb Remove the SSLEEP case from the load average computation. This has
been a no-op for as long as our CVS history goes back. Processes in
state SSLEEP could only be counted if p_slptime == 0, but immediately
before loadav() is called, schedcpu() has just incremented p_slptime
on all SSLEEP processes.
2001-10-04 22:33:31 +00:00
Robert Watson
8c5d4fe829 o Modify access control checks in mmap() to use securelevel_gt() instead
of direct variable access.

Obtained from:	TrustedBSD Project
2001-09-26 20:29:39 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00
Peter Wemm
eb30c1c0b9 Rip some well duplicated code out of cpu_wait() and cpu_exit() and move
it to the MI area.  KSE touched cpu_wait() which had the same change
replicated five ways for each platform.  Now it can just do it once.
The only MD parts seemed to be dealing with fpu state cleanup and things
like vm86 cleanup on x86.  The rest was identical.

XXX: ia64 and powerpc did not have cpu_throw(), so I've put a functional
stub in place.

Reviewed by:	jake, tmm, dillon
2001-09-10 04:28:58 +00:00
John Baldwin
29fdb744d1 Process priority is locked by the sched_lock, not the proc lock. 2001-09-01 20:16:30 +00:00
Matthew Dillon
7feaf028be make swapon() MPSAFE (will adjust syscalls.master later) 2001-08-31 22:15:37 +00:00
Matthew Dillon
6a33d53c48 mark obreak() and ovadvise() as being MPSAFE 2001-08-31 22:10:03 +00:00
Matthew Dillon
d2c60af81a Cleanup 2001-08-31 01:26:30 +00:00
Peter Wemm
3516c025ff Implement idle zeroing of pages. I've been tinkering with this
on and off since John Dyson left his work-in-progress.

It is off by default for now.  sysctl vm.zeroidle_enable=1 to turn it on.

There are some hacks here to deal with the present lack of preemption - we
yield after doing a small number of pages since we wont preempt otherwise.

This is basically Matt's algorithm [with hysteresis] with an idle process
to call it in a similar way it used to be called from the idle loop.

I cleaned up the includes a fair bit here too.
2001-08-25 05:00:44 +00:00
Matthew Dillon
676274db9b Remove support for the badly broken MAP_INHERIT (from -current only). 2001-08-24 19:29:56 +00:00
Matthew Dillon
219d632c15 Move most of the kernel submap initialization code, including the
timeout callwheel and buffer cache, out of the platform specific areas
and into the machine independant area.  i386 and alpha adjusted here.
Other cpus can be fixed piecemeal.

Reviewed by:    freebsd-smp, jake
2001-08-22 04:07:27 +00:00
Matthew Dillon
0b76df7146 KASSERT if vm_page_t->wire_count overflows. 2001-08-22 04:01:56 +00:00
Matthew Dillon
2f9e4e8025 Limit the amount of KVM reserved for the buffer cache and for swap-meta
information.  The default limits only effect machines with > 1GB of ram
and can be overriden with two new kernel conf variables VM_SWZONE_SIZE_MAX
and VM_BCACHE_SIZE_MAX, or with loader variables kern.maxswzone and
kern.maxbcache.  This has the effect of leaving more KVM available for
sizing NMBCLUSTERS and 'maxusers' and should avoid tripups where a sysad
adds memory to a machine and then sees the kernel panic on boot due to
running out of KVM.

Also change the default swap-meta auto-sizing calculation to allocate half
of what it was previously allocating.  The prior defaults were way too high.
Note that we cannot afford to run out of swap-meta structures so we still
stay somewhat conservative here.
2001-08-20 00:41:12 +00:00
John Baldwin
02cd7c3cf2 - Remove asleep(), await(), and M_ASLEEP.
- Callers of asleep() and await() have been converted to calling tsleep().
  The only caller outside of M_ASLEEP was the ata driver, which called both
  asleep() and await() with spl-raised, so there was no need for the
  asleep() and await() pair.  M_ASLEEP was unused.

Reviewed by:	jasone, peter
2001-08-10 06:56:12 +00:00
John Baldwin
8ec48c6dbf - Remove asleep(), await(), and M_ASLEEP.
- Callers of asleep() and await() have been converted to calling tsleep().
  The only caller outside of M_ASLEEP was the ata driver, which called both
  asleep() and await() with spl-raised, so there was no need for the
  asleep() and await() pair.  M_ASLEEP was unused.

Reviewed by:	jasone, peter
2001-08-10 06:37:05 +00:00
Thomas Moestl
59fa485c3e Add a missing semicolon to unbreak the kernel build with INVARIANTS
(which was unfortunately turned off in the confguration I used for the
last test build).

Spotted by:	jake
Pointy hat to:	tmm
2001-08-05 03:55:02 +00:00
John Baldwin
bd8e0d5871 Whitespace fixes. 2001-08-04 20:49:29 +00:00
Thomas Moestl
b4c53a8111 Add a zdestroy() function to the zone allocator. This is needed for the
unload case of modules that use their own zones.
It has been tested with the nfs module.
2001-08-04 20:17:05 +00:00
Alfred Perlstein
61ce6eeee3 Fixups for the initial allocation by dillon:
1) allocate fewer buckets
  2) when failing to allocate swap zone, keep reducing the zone by
     a third rather than a half in order to reduce the chance of
     allocating way too little.

I also moved around some code for readability.

Suggested by: dillon
Reviewed by: dillon
2001-08-02 07:54:58 +00:00
Jake Burkholder
3a9b5daf48 Oops. Last commit to vm_object.c should have got these files too.
Remove the use of atomic ops to manipulate vm_object and vm_page flags.
Giant is required here, so they are superfluous.

Discussed with:	dillon
2001-07-31 04:09:52 +00:00
Jake Burkholder
b06805ad34 Remove the use of atomic ops to manipulate vm_object and vm_page flags.
Giant is required here, so they are superfluous.

Discussed with:	dillon
2001-07-31 04:03:53 +00:00
Ian Dowse
a4821e444e Permit direct swapping to NFS regular files using swapon(2). We
already allow this for NFS swap configured via BOOTP, so it is
known to work fine.

For many diskless configurations is is more flexible to have the
client set up swapping itself; it can recreate a sparse swap file
to save on server space for example, and it works with a non-NFS
root filesystem such as an in-kernel filesystem image.
2001-07-28 20:18:38 +00:00
Assar Westerlund
d3e5863fa9 make vm_page_select_cache static
Requested by:	bde
2001-07-23 12:34:31 +00:00
Assar Westerlund
0379d76358 (vm_page_select_cache): add prototype 2001-07-21 17:08:15 +00:00
Benno Rice
1f246456a5 The i386-specific includes in this file were "fixed" by bracketing them with
#ifndef __alpha__.  Fix this for the rest of the world by turning it into
#ifdef __i386__.

Reviewed by:	obrien
2001-07-15 04:11:51 +00:00
Dag-Erling Smørgrav
bf3009895e Fix missing newline and terminator at the end of the vm.zone sysctl. 2001-07-09 03:37:33 +00:00
Matt Jacob
f343cf2135 Apply field bandages to the includes so compiles happen on alpha. 2001-07-05 06:13:44 +00:00
Matthew Dillon
7197571105 Move vm_page_zero_idle() from machine-dependant sections to a
machine-independant source file, vm/vm_zeroidle.c.  It was exactly the
same for all platforms and updating them all was getting annoying.
2001-07-05 01:32:42 +00:00
Matthew Dillon
6d03d577a5 Reorg vm_page.c into vm_page.c, vm_pageq.c, and vm_contig.c (for contigmalloc).
Also removed some spl's and added some VM mutexes, but they are not actually
used yet, so this commit does not really make any operational changes
to the system.

vm_page.c relates to vm_page_t manipulation, including high level deactivation,
activation, etc...  vm_pageq.c relates to finding free pages and aquiring
exclusive access to a page queue (exclusivity part not yet implemented).
And the world still builds... :-)
2001-07-04 23:27:09 +00:00