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* /* -> /*- for license, minor formatting changesimp2005-01-071-1/+1
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* Access the swap_pagers' ->putpages() through swappagerops insteadphk2003-08-061-1/+1
| | | | of directly, this is a cleaner way to do it.
* Use sparse struct initializations for struct pagerops.phk2003-08-051-7/+5
| | | | This makes grepping for which pagers implement which methods easier.
* Use __FBSDID().obrien2003-06-111-2/+3
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* Remove references to vm_zone.h and switch over to the new uma API.jeff2002-03-201-1/+0
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* Remove __P.alfred2002-03-191-8/+8
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* - Remove a number of extra newlines that do not belong here according toeivind2002-03-101-4/+0
| | | | | | | | | style(9) - Minor space adjustment in cases where we have "( ", " )", if(), return(), while(), for(), etc. - Add /* SYMBOL */ after a few #endifs. Reviewed by: alc
* With Alfred's permission, remove vm_mtx in favor of a fine-grained approachdillon2001-07-041-0/+1
| | | | | | | | | (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.
* Introduce a global lock for the vm subsystem (vm_mtx).alfred2001-05-191-0/+2
| | | | | | | | | | | | | | | | | | | 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
* - If swap metadata does not fit into the KVM, reduce the number oftanimura2000-12-131-0/+1
| | | | | | | | | | | | | | | struct swblock entries by dividing the number of the entries by 2 until the swap metadata fits. - Reject swapon(2) upon failure of swap_zone allocation. This is just a temporary fix. Better solutions include: (suggested by: dillon) o reserving swap in SWAP_META_PAGES chunks, and o swapping the swblock structures themselves. Reviewed by: alfred, dillon
* Revert spelling mistake I made in the previous commitcharnier2000-03-271-1/+1
| | | | Requested by: Alan and Bruce
* Spellingcharnier2000-03-261-1/+1
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* Remove unused #include's.alc1999-11-071-2/+0
| | | | Submitted by: phk
* The functions declared by this header file no longer exist.alc1999-11-071-1/+0
| | | | Submitted by: phk (in part)
* useracc() the prequel:phk1999-10-291-1/+0
| | | | | | | | | | | 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.
* $Id$ -> $FreeBSD$peter1999-08-281-1/+1
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* vm_pager_put_pages() is passed an rcval array to hold per-page returndillon1999-01-241-4/+4
| | | | | | | 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.
* The default_pager's interaction with the swap_pager has been reorganized,dillon1999-01-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | and the swap_pager has been completely replaced. The new swap pager uses the new blist radix-tree based bitmap allocator for low level swap allocation and deallocation. The new allocator is effectively O(5) while the old one was O(N), and the new allocator allocates all required memory at init time rather then at allocate memory on the fly at run time. Swap metadata is allocated in clusters and stored in a hash table, eliminating linearly allocated structures. Many, many features have been rewritten or added. Swap space is now reallocated on the fly providing a poor-mans auto defragmentation of swap space. Swap space that is no longer needed is freed on a timely basis so no garbage collection is necessary. Swap I/O is marked B_ASYNC and NFS has been fixed to do the right thing with it, so NFS-based paging now has around 10x the performance as it did before ( previously NFS enforced synchronous I/O for paging ).
* This is a rather large commit that encompasses the new swapper,dillon1999-01-211-41/+41
| | | | | | | | | | 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>
* Fixed two potentially serious classes of bugs:dg1998-10-131-4/+4
| | | | | | | | | | | | | | | | 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.
* Back out DIAGNOSTIC changes.eivind1998-02-061-3/+1
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* Turn DIAGNOSTIC into a new-style option.eivind1998-02-041-1/+3
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* Removed unused #includes.bde1997-09-011-4/+1
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* Fixed type mismatches for functions with args of type vm_prot_t and/orbde1997-08-251-6/+3
| | | | | | | | | vm_inherit_t. These types are smaller than ints, so the prototypes should have used the promoted type (int) to match the old-style function definitions. They use just vm_prot_t and/or vm_inherit_t. This depends on gcc features to work. I fixed the definitions since this is easiest. The correct fix may be to change the small types to u_int, to optimize for time instead of space.
* Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are notpeter1997-02-221-1/+1
| | | | ready for it yet.
* Make the long-awaited change from $Id$ to $FreeBSD$jkh1997-01-141-1/+1
| | | | | | | | 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.
* Various bugfixes/cleanups from me and others:dyson1996-06-161-1/+14
| | | | | | | | | | | | 1) Remove potential race conditions on waking up in vm_page_free_wakeup by making sure that it is at splvm(). 2) Fix another bug in vm_map_simplify_entry. 3) Be more complete about converting from default to swap pager when an object grows to be large enough that there can be a problem with data structure allocation under low memory conditions. 4) Make some madvise code more efficient. 5) Added some comments.
* Make sure that pageout deadlocks cannot occur. There is a problemdyson1996-05-291-7/+15
| | | | | | | | | that the datastructures needed to support the swap pager can take enough space to fully deplete system memory, and cause a deadlock. This change keeps large objects from being filled with dirty pages without the appropriate swap pager datastructures. Right now, default objects greater than 1/4 the size of available system memory are converted to swap objects, thereby eliminating the risk of deadlock.
* Make the conversion from the default pager to swap pager more robustdyson1996-05-241-5/+7
| | | | in the face of low memory conditions.
* Eliminated many redundant vm_map_lookup operations for vm_mmap.dyson1996-01-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | Speed up for vfs_bio -- addition of a routine bqrelse to greatly diminish overhead for merged cache. Efficiency improvement for vfs_cluster. It used to do alot of redundant calls to cluster_rbuild. Correct the ordering for vrele of .text and release of credentials. Use the selective tlb update for 486/586/P6. Numerous fixes to the size of objects allocated for files. Additionally, fixes in the various pagers. Fixes for proper positioning of vnode_pager_setsize in msdosfs and ext2fs. Fixes in the swap pager for exhausted resources. The pageout code will not as readily thrash. Change the page queue flags (PG_ACTIVE, PG_INACTIVE, PG_FREE, PG_CACHE) into page queue indices (PQ_ACTIVE, PQ_INACTIVE, PQ_FREE, PQ_CACHE), thereby improving efficiency of several routines. Eliminate even more unnecessary vm_page_protect operations. Significantly speed up process forks. Make vm_object_page_clean more efficient, thereby eliminating the pause that happens every 30seconds. Make sequential clustered writes B_ASYNC instead of B_DELWRI even in the case of filesystems mounted async. Fix a panic with busy pages when write clustering is done for non-VMIO buffers.
* Another mega commit to staticize things.phk1995-12-141-6/+14
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* Changes to support 1Tb filesizes. Pages are now named by andyson1995-12-111-4/+4
| | | | (object,index) pair instead of (object,offset) pair.
* Untangled the vm.h include file spaghetti.dg1995-12-071-2/+6
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* Added a copyright to this file.dg1995-07-131-0/+33
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* Oops, forgot to add the "default" pager files...dg1995-07-131-0/+100
NOTE: libkvm, w, ps, 'top', and any other utility which depends on struct proc or any VM system structure will have to be rebuilt!!! Much needed overhaul of the VM system. Included in this first round of changes: 1) Improved pager interfaces: init, alloc, dealloc, getpages, putpages, haspage, and sync operations are supported. The haspage interface now provides information about clusterability. All pager routines now take struct vm_object's instead of "pagers". 2) Improved data structures. In the previous paradigm, there is constant confusion caused by pagers being both a data structure ("allocate a pager") and a collection of routines. The idea of a pager structure has escentially been eliminated. Objects now have types, and this type is used to index the appropriate pager. In most cases, items in the pager structure were duplicated in the object data structure and thus were unnecessary. In the few cases that remained, a un_pager structure union was created in the object to contain these items. 3) Because of the cleanup of #1 & #2, a lot of unnecessary layering can now be removed. For instance, vm_object_enter(), vm_object_lookup(), vm_object_remove(), and the associated object hash list were some of the things that were removed. 4) simple_lock's removed. Discussion with several people reveals that the SMP locking primitives used in the VM system aren't likely the mechanism that we'll be adopting. Even if it were, the locking that was in the code was very inadequate and would have to be mostly re-done anyway. The locking in a uni-processor kernel was a no-op but went a long way toward making the code difficult to read and debug. 5) Places that attempted to kludge-up the fact that we don't have kernel thread support have been fixed to reflect the reality that we are really dealing with processes, not threads. The VM system didn't have complete thread support, so the comments and mis-named routines were just wrong. We now use tsleep and wakeup directly in the lock routines, for instance. 6) Where appropriate, the pagers have been improved, especially in the pager_alloc routines. Most of the pager_allocs have been rewritten and are now faster and easier to maintain. 7) The pagedaemon pageout clustering algorithm has been rewritten and now tries harder to output an even number of pages before and after the requested page. This is sort of the reverse of the ideal pagein algorithm and should provide better overall performance. 8) Unnecessary (incorrect) casts to caddr_t in calls to tsleep & wakeup have been removed. Some other unnecessary casts have also been removed. 9) Some almost useless debugging code removed. 10) Terminology of shadow objects vs. backing objects straightened out. The fact that the vm_object data structure escentially had this backwards really confused things. The use of "shadow" and "backing object" throughout the code is now internally consistent and correct in the Mach terminology. 11) Several minor bug fixes, including one in the vm daemon that caused 0 RSS objects to not get purged as intended. 12) A "default pager" has now been created which cleans up the transition of objects to the "swap" type. The previous checks throughout the code for swp->pg_data != NULL were really ugly. This change also provides the rudiments for future backing of "anonymous" memory by something other than the swap pager (via the vnode pager, for example), and it allows the decision about which of these pagers to use to be made dynamically (although will need some additional decision code to do this, of course). 13) (dyson) MAP_COPY has been deprecated and the corresponding "copy object" code has been removed. MAP_COPY was undocumented and non- standard. It was furthermore broken in several ways which caused its behavior to degrade to MAP_PRIVATE. Binaries that use MAP_COPY will continue to work correctly, but via the slightly different semantics of MAP_PRIVATE. 14) (dyson) Sharing maps have been removed. It's marginal usefulness in a threads design can be worked around in other ways. Both #12 and #13 were done to simplify the code and improve readability and maintain- ability. (As were most all of these changes) TODO: 1) Rewrite most of the vnode pager to use VOP_GETPAGES/PUTPAGES. Doing this will reduce the vnode pager to a mere fraction of its current size. 2) Rewrite vm_fault and the swap/vnode pagers to use the clustering information provided by the new haspage pager interface. This will substantially reduce the overhead by eliminating a large number of VOP_BMAP() calls. The VOP_BMAP() filesystem interface should be improved to provide both a "behind" and "ahead" indication of contiguousness. 3) Implement the extended features of pager_haspage in swap_pager_haspage(). It currently just says 0 pages ahead/behind. 4) Re-implement the swap device (swstrategy) in a more elegant way, perhaps via a much more general mechanism that could also be used for disk striping of regular filesystems. 5) Do something to improve the architecture of vm_object_collapse(). The fact that it makes calls into the swap pager and knows too much about how the swap pager operates really bothers me. It also doesn't allow for collapsing of non-swap pager objects ("unnamed" objects backed by other pagers).
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