Commit Graph

2507 Commits

Author SHA1 Message Date
jhb
80d9458a56 Adjust some variables (mostly related to the buffer cache) that hold
address space sizes to be longs instead of ints.  Specifically, the follow
values are now longs: runningbufspace, bufspace, maxbufspace,
bufmallocspace, maxbufmallocspace, lobufspace, hibufspace, lorunningspace,
hirunningspace, maxswzone, maxbcache, and maxpipekva.  Previously, a
relatively small number (~ 44000) of buffers set in kern.nbuf would result
in integer overflows resulting either in hangs or bogus values of
hidirtybuffers and lodirtybuffers.  Now one has to overflow a long to see
such problems.  There was a check for a nbuf setting that would cause
overflows in the auto-tuning of nbuf.  I've changed it to always check and
cap nbuf but warn if a user-supplied tunable would cause overflow.

Note that this changes the ABI of several sysctls that are used by things
like top(1), etc., so any MFC would probably require a some gross shims
to allow for that.

MFC after:	1 month
2009-03-09 19:35:20 +00:00
alc
8a8f5251fa Prior to r188331 a map entry's last read offset was only updated by a hard
fault.  In r188331 this update was relocated because of synchronization
changes to a place where it would occur on both hard and soft faults.  This
change again restricts the update to hard faults.
2009-02-25 07:52:53 +00:00
kib
66c697aade Revert the addition of the freelist argument for the vm_map_delete()
function, done in r188334. Instead, collect the entries that shall be
freed, in the deferred_freelist member of the map. Automatically purge
the deferred freelist when map is unlocked.

Tested by:	pho
Reviewed by:	alc
2009-02-24 20:57:43 +00:00
kib
47de55da04 Add the assertion macros for the map locks. Use them in several map
manipulation functions.

Tested by:	pho
Reviewed by:	alc
2009-02-24 20:43:29 +00:00
kib
8ee2717f0a Update the comment after the r188334.
Reviewed by:	alc
2009-02-24 20:23:16 +00:00
rdivacky
e5bfcba080 Change the functions to ANSI in those cases where it breaks promotion
to int rule. See ISO C Standard: SS6.7.5.3:15.

Approved by:	kib (mentor)
Reviewed by:	warner
Tested by:	silence on -current
2009-02-24 18:09:31 +00:00
rwatson
a0f4221805 Put debug.vm_lowmem sysctl under DIAGNOSTIC.
Submitted by:	sam
MFC after:	3 days
2009-02-23 23:30:17 +00:00
rwatson
967fa55dfb Add a debugging sysctl, debug.vm_lowmem, that when assigned a value of
1 will trigger a pass through the VM's low-memory handlers, such as
protocol and UMA drain routines.  This makes it easier to exercise
these otherwise rarely-invoked code paths.

MFC after:	3 days
2009-02-23 23:00:12 +00:00
alc
41927ea850 Reduce the scope of the page queues lock in vm_object_page_remove().
MFC after:	1 week
2009-02-21 20:57:25 +00:00
alc
6c9e695281 Eliminate stale comments. 2009-02-20 16:19:34 +00:00
kib
aeba79ddd1 Comment out the assertion from r188321. It is not valid for nfs.
Reported by:	alc
2009-02-09 11:32:23 +00:00
alc
e3d0161279 Avoid some cases of unnecessary page queues locking by vm_fault's delete-
behind heuristic.
2009-02-09 06:23:21 +00:00
alc
9513bac196 Eliminate OBJ_NEEDGIANT. After r188331, OBJ_NEEDGIANT's only use is by a
redundant assertion in vm_fault().

Reviewed by:	kib
2009-02-08 22:17:24 +00:00
kib
9988f9e959 Remove no longer valid comment.
Submitted by:	alc
2009-02-08 21:20:13 +00:00
kib
fc6cc1f763 Improve comments, correct English.
Submitted by:	alc
2009-02-08 20:52:09 +00:00
kib
ae7c4cfa11 Do not call vm_object_deallocate() from vm_map_delete(), because we
hold the map lock there, and might need the vnode lock for OBJT_VNODE
objects. Postpone object deallocation until caller of vm_map_delete()
drops the map lock. Link the map entries to be freed into the freelist,
that is released by the new helper function vm_map_entry_free_freelist().

Reviewed by:	tegge, alc
Tested by:	pho
2009-02-08 20:39:17 +00:00
kib
9a341e28eb In vm_map_sync(), do not call vm_object_sync() while holding map lock.
Reference object, drop the map lock, and then call vm_object_sync().
The object sync might require vnode lock for OBJT_VNODE type objects.

Reviewed by:	tegge
Tested by:	pho
2009-02-08 20:30:51 +00:00
kib
379838428b Do not sleep for vnode lock while holding map lock in vm_fault. Try to
acquire vnode lock for OBJT_VNODE object after map lock is dropped.
Because we have the busy page(s) in the object, sleeping there would
result in deadlock with vnode resize. Try to get lock without sleeping,
and, if the attempt failed, drop the state, lock the vnode, and restart
the fault handler from the start with already locked vnode.

Because the vnode_pager_lock() function is inlined in vm_fault(),
axe it.

Based on suggestion by:	alc
Reviewed by:	tegge, alc
Tested by:	pho
2009-02-08 20:23:46 +00:00
kib
6f193f1588 Add the comments to vm_map_simplify_entry() and vmspace_fork(),
describing why several calls to vm_deallocate_object() with locked map
do not result in the acquisition of the vnode lock after map lock.

Suggested and reviewed by:	tegge
2009-02-08 20:00:33 +00:00
kib
2d39ccdd94 Lock the new map in vmspace_fork(). The newly allocated map should not
be accessible outside vmspace_fork() yet, but locking it would satisfy
the protocol of the vm_map_entry_link() and other functions called
from vmspace_fork().

Use trylock that is supposedly cannot fail, to silence WITNESS warning
of the nested acquisition of the sx lock with the same name.

Suggested and reviewed by:	tegge
2009-02-08 19:55:03 +00:00
kib
0125db5772 Assert that vnode is exclusively locked when its vm object is resized.
Reviewed by:	tegge
2009-02-08 19:44:50 +00:00
kib
7a52ad11f4 Do not leak the MAP_ENTRY_IN_TRANSITION flag when copying map entry
on fork. Otherwise, copied entry cannot be removed in the child map.

Reviewed by:	tegge
MFC after:	2 weeks
2009-02-08 19:41:08 +00:00
kib
b798264c6d Style. 2009-02-08 19:37:01 +00:00
jeff
69d1bd8670 - Make the keg abstraction more complete. Permit a zone to have multiple
backend kegs so it may source compatible memory from multiple backends.
   This is useful for cases such as NUMA or different layouts for the same
   memory type.
 - Provide a new api for adding new backend kegs to secondary zones.
 - Provide a new flag for adjusting the layout of zones to stagger
   allocations better across cache lines.

Sponsored by:	Nokia
2009-01-25 09:11:24 +00:00
jhb
a9601871c9 - Mark all standalone INT/LONG/QUAD sysctl's MPSAFE. This is done
inside the SYSCTL() macros and thus does not need to be done for
  all of the nodes scattered across the source tree.
- Mark the name-cache related sysctl's (including debug.hashstat.*) MPSAFE.
- Mark vm.loadavg MPSAFE.
- Remove GIANT_REQUIRED from vmtotal() (everything in this routine already
  has sufficient locking) and mark vm.vmtotal MPSAFE.
- Mark the vm.stats.(sys|vm).* sysctls MPSAFE.
2009-01-23 22:49:23 +00:00
jhb
dc43531891 Now that vfs_markatime() no longer requires an exclusive lock due to
the VOP_MARKATIME() changes, use a shared vnode lock for mmap().

Submitted by:	ups
2009-01-21 14:43:35 +00:00
kib
ac1b596fda Extend the struct vm_page wire_count to u_int to avoid the overflow
of the counter, that may happen when too many sendfile(2) calls are
being executed with this vnode [1].

To keep the size of the struct vm_page and offsets of the fields
accessed by out-of-tree modules, swap the types and locations
of the wire_count and cow fields. Add safety checks to detect cow
overflow and force fallback to the normal copy code for zero-copy
sockets. [2]

Reported by:	Anton Yuzhaninov <citrin citrin ru> [1]
Suggested by:	alc [2]
Reviewed by:	alc
MFC after:	2 weeks
2009-01-03 13:24:08 +00:00
alc
a2ba509efc Resurrect shared map locks allowing greater concurrency during some map
operations, such as page faults.

An earlier version of this change was ...

Reviewed by:	kib
Tested by:	pho
MFC after:	6 weeks
2009-01-01 00:31:46 +00:00
alc
81e94e0a4c Update or eliminate some stale comments. 2008-12-31 05:44:05 +00:00
alc
fa3b7c7db3 Avoid an unnecessary memory dereference in vm_map_entry_splay(). 2008-12-30 21:52:18 +00:00
alc
c1be5ff444 Style change to vm_map_lookup(): Eliminate a macro of dubious value. 2008-12-30 20:51:07 +00:00
alc
96037be899 Move the implementation of the vm map's fast path on address lookup from
vm_map_lookup{,_locked}() to vm_map_lookup_entry().  Having the fast path
in vm_map_lookup{,_locked}() limits its benefits to page faults.  Moving
it to vm_map_lookup_entry() extends its benefits to other operations on
the vm map.
2008-12-30 19:48:03 +00:00
rnoland
63e9bb0efa Fix printing of KASSERT message missed in r163604.
Approved by:	kib
2008-12-21 16:56:13 +00:00
kib
4edc1f9451 Instead of forcing vn_start_write() to reset mp back to NULL for the
failed calls with non-NULL vp, explicitely clear mp after failure.

Tested by:	stass
Reviewed by:	tegge
PR:		123768
MFC after:	1 week
2008-11-16 21:57:54 +00:00
raj
032a270ba5 Support kernel crash mini dumps on ARM architecture.
Obtained from:	Juniper Networks, Semihalf
2008-11-06 16:20:27 +00:00
keramida
4b957256d0 Various comment nits, and typos. 2008-11-02 00:41:26 +00:00
rwatson
3667673537 Update mmap() comment: no more block devices, so no more block device
cache coherency questions.

MFC after:	3 days
2008-10-22 16:50:12 +00:00
attilio
b8bf37e585 Remove the struct thread unuseful argument from bufobj interface.
In particular following functions KPI results modified:
- bufobj_invalbuf()
- bufsync()

and BO_SYNC() "virtual method" of the buffer objects set.
Main consumers of bufobj functions are affected by this change too and,
in particular, functions which changed their KPI are:
- vinvalbuf()
- g_vfs_close()

Due to the KPI breakage, __FreeBSD_version will be bumped in a later
commit.

As a side note, please consider just temporary the 'curthread' argument
passing to VOP_SYNC() (in bufsync()) as it will be axed out ASAP

Reviewed by:	kib
Tested by:	Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
2008-10-10 21:23:50 +00:00
kib
de9e891748 Move the code for doing out-of-memory grass from vm_pageout_scan()
into the separate function vm_pageout_oom(). Supply a parameter for
vm_pageout_oom() describing a reason for the call.

Call vm_pageout_oom() from the swp_pager_meta_build() when swap zone
is exhausted.

Reviewed by:	alc
Tested by:	pho, jhb
MFC after:	2 weeks
2008-09-29 19:45:12 +00:00
emaste
a173e0f84d Move CTASSERT from header file to source file, per implementation note now
in the CTASSERT man page.
2008-09-26 18:44:40 +00:00
kib
496b70bc6a Save previous content of the td_fpop before storing the current
filedescriptor into it. Make sure that td_fpop is NULL when calling
d_mmap from dev_pager_getpages().

Change guards against td_fpop field being non-NULL with private state
for another device, and against sudden clearing the td_fpop. This
could occur when either a driver method calls another driver through
the filedescriptor operation, or a page fault happen while driver is
writing to a memory backed by another driver.

Noted by:	rwatson
Tested by:	rnoland
MFC after:	3 days
2008-09-26 14:50:49 +00:00
alc
409b7f1ce0 Prevent an integer overflow in vm_pageout_page_stats() on machines with a
large number of physical pages.

PR:		126158
Submitted by:	Dmitry Tejblum
MFC after:	3 days
2008-09-21 18:01:34 +00:00
kib
2a1cba02c6 Allow the d_mmap driver methods to use cdevpriv KPI during verification
phase of establishing mapping.

Discussed with:	rwatson, jhb, rnoland
Tested by:	rnoland
MFC after:	3 days
2008-09-20 19:56:02 +00:00
attilio
dbf35e279f Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread
was always curthread and totally unuseful.

Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
2008-08-28 15:23:18 +00:00
antoine
d4ceeb8daa Remove unused variable nosleepwithlocks.
PR:		126609
Submitted by:	Mateusz Guzik
MFC after:	1 month
X-MFC:		to stable/7 only, this variable is still used in stable/6
2008-08-23 12:40:07 +00:00
nwhitehorn
077618820d Allow the MD UMA allocator to use VM routines like kmem_*(). Existing code requires MD allocator to be available early in the boot process, before the VM is fully available. This defines a new VM define (UMA_MD_SMALL_ALLOC_NEEDS_VM) that allows an MD UMA small allocator to become available at the same time as the default UMA allocator.
Approved by:	marcel (mentor)
2008-08-23 01:35:36 +00:00
julian
0592958505 A bunch of formatting fixes brough to light by, or created by the Vimage commit
a few days ago.
2008-08-20 01:05:56 +00:00
kmacy
de0a83a794 Work around differences in page allocation for initial page tables on xen
MFC after:	1 month
2008-08-17 23:40:29 +00:00
emaste
b30356b634 Fix REDZONE(9) on amd64 and perhaps other 64 bit targets -- ensure the space
that redzone adds to the allocation for storing its metadata is at least as
large as the metadata that it will store there.

Submitted by:	Nima Misaghian
2008-08-13 17:32:48 +00:00
jhb
8af56fb687 If a thread that is swapped out is made runnable, then the setrunnable()
routine wakes up proc0 so that proc0 can swap the thread back in.
Historically, this has been done by waking up proc0 directly from
setrunnable() itself via a wakeup().  When waking up a sleeping thread
that was swapped out (the usual case when waking proc0 since only sleeping
threads are eligible to be swapped out), this resulted in a bit of
recursion (e.g. wakeup() -> setrunnable() -> wakeup()).

With sleep queues having separate locks in 6.x and later, this caused a
spin lock LOR (sleepq lock -> sched_lock/thread lock -> sleepq lock).
An attempt was made to fix this in 7.0 by making the proc0 wakeup use
the ithread mechanism for doing the wakeup.  However, this required
grabbing proc0's thread lock to perform the wakeup.  If proc0 was asleep
elsewhere in the kernel (e.g. waiting for disk I/O), then this degenerated
into the same LOR since the thread lock would be some other sleepq lock.

Fix this by deferring the wakeup of the swapper until after the sleepq
lock held by the upper layer has been locked.  The setrunnable() routine
now returns a boolean value to indicate whether or not proc0 needs to be
woken up.  The end result is that consumers of the sleepq API such as
*sleep/wakeup, condition variables, sx locks, and lockmgr, have to wakeup
proc0 if they get a non-zero return value from sleepq_abort(),
sleepq_broadcast(), or sleepq_signal().

Discussed with:	jeff
Glanced at by:	sam
Tested by:	Jurgen Weber  jurgen - ish com au
MFC after:	2 weeks
2008-08-05 20:02:31 +00:00