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* 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.
* Prepare better for multi-platform by eliminating another requireddyson1997-01-111-3/+7
| | | | | pmap routine (pmap_is_referenced.) Upper level recoded to use pmap_ts_referenced.
* Removed __pure's and __pure2's. __pure is a no-op for recent versionsbde1996-10-121-7/+5
| | | | | of gcc by definition, and __pure2 is a no-op in effect (presumably the compiler can see when an inline function has no side effects).
* Addition of page coloring support. Various levels of coloring are afforded.dyson1996-09-081-2/+3
| | | | | | 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.)
* Backed out the recent changes/enhancements to the VM code. Thedyson1996-07-301-18/+11
| | | | | | | problem with the 'shell scripts' was found, but there was a 'strange' problem found with a 486 laptop that we could not find. This commit backs the code back to 25-jul, and will be re-entered after the snapshot in smaller (more easily tested) chunks.
* This commit is meant to solve a couple of VM system problems ordyson1996-07-271-11/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | performance issues. 1) The pmap module has had too many inlines, and so the object file is simply bigger than it needs to be. Some common code is also merged into subroutines. 2) Removal of some *evil* PHYS_TO_VM_PAGE macro calls. Unfortunately, a few have needed to be added also. The removal caused the need for more vm_page_lookups. I added lookup hints to minimize the need for the page table lookup operations. 3) Removal of some bogus performance improvements, that mostly made the code more complex (tracking individual page table page updates unnecessarily). Those improvements actually hurt 386 processors perf (not that people who worry about perf use 386 processors anymore :-)). 4) Changed pv queue manipulations/structures to be TAILQ's. 5) The pv queue code has had some performance problems since day one. Some significant scalability issues are resolved by threading the pv entries from the pmap AND the physical address instead of just the physical address. This makes certain pmap operations run much faster. This does not affect most micro-benchmarks, but should help loaded system performance *significantly*. DG helped and came up with most of the solution for this one. 6) Most if not all pmap bit operations follow the pattern: pmap_test_bit(); pmap_clear_bit(); That made for twice the necessary pv list traversal. The pmap interface now supports only pmap_tc_bit type operations: pmap_[test/clear]_modified, pmap_[test/clear]_referenced. Additionally, the modified routine now takes a vm_page_t arg instead of a phys address. This eliminates a PHYS_TO_VM_PAGE operation. 7) Several rewrites of routines that contain redundant code to use common routines, so that there is a greater likelihood of keeping the cache footprint smaller.
* Mostly superficial code improvements, add a diagnostic. Thedyson1996-06-101-18/+23
| | | | | | code improvements include significant simplification of the reservation of the swap pager control blocks for reads. Add a panic for an inconsistent swap pager control block count.
* Initial support for MADV_FREE, support for pages that we don't caredyson1996-05-231-1/+27
| | | | | | about the contents anymore. This gives us alot of the advantage of freeing individual pages through munmap, but with almost none of the overhead.
* This set of commits to the VM system does the following, and containdyson1996-05-181-22/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | contributions or ideas from Stephen McKay <syssgm@devetir.qld.gov.au>, Alan Cox <alc@cs.rice.edu>, David Greenman <davidg@freebsd.org> and me: More usage of the TAILQ macros. Additional minor fix to queue.h. Performance enhancements to the pageout daemon. Addition of a wait in the case that the pageout daemon has to run immediately. Slightly modify the pageout algorithm. Significant revamp of the pmap/fork code: 1) PTE's and UPAGES's are NO LONGER in the process's map. 2) PTE's and UPAGES's reside in their own objects. 3) TOTAL elimination of recursive page table pagefaults. 4) The page directory now resides in the PTE object. 5) Implemented pmap_copy, thereby speeding up fork time. 6) Changed the pv entries so that the head is a pointer and not an entire entry. 7) Significant cleanup of pmap_protect, and pmap_remove. 8) Removed significant amounts of machine dependent fork code from vm_glue. Pushed much of that code into the machine dependent pmap module. 9) Support more completely the reuse of already zeroed pages (Page table pages and page directories) as being already zeroed. Performance and code cleanups in vm_map: 1) Improved and simplified allocation of map entries. 2) Improved vm_map_copy code. 3) Corrected some minor problems in the simplify code. Implemented splvm (combo of splbio and splimp.) The VM code now seldom uses splhigh. Improved the speed of and simplified kmem_malloc. Minor mod to vm_fault to avoid using pre-zeroed pages in the case of objects with backing objects along with the already existant condition of having a vnode. (If there is a backing object, there will likely be a COW... With a COW, it isn't necessary to start with a pre-zeroed page.) Minor reorg of source to perhaps improve locality of ref.
* Another sweep over the pmap/vm macros, this time with more focus onphk1996-05-031-3/+3
| | | | | the usage. I'm not satisfied with the naming, but now at least there is less bogus stuff around.
* removed:phk1996-05-021-2/+2
| | | | | | | | | CLBYTES PD_SHIFT PGSHIFT NBPG PGOFSET CLSIZELOG2 CLSIZE pdei() ptei() kvtopte() ptetov() ispt() ptetoav() &c &c new: NPDEPG Major macro cleanup.
* Fix a problem in the swap pager that caused some of the pages thatdyson1996-03-061-9/+9
| | | | | | | | | were paged in under low swap space conditions to both loose their backing store and their dirty bits. This would cause pages to be demand zeroed under certain conditions in low VM space conditions and consequential sig-11's or sig-10's. This situation was made worse lately when the level for swap space reclaim threshold was increased.
* In order to fix some concurrency problems with the swap pager earlydyson1996-03-031-2/+2
| | | | | | | on in the FreeBSD development, I had made a global lock around the rlist code. This was bogus, and now the lock is maintained on a per resource list basis. This now allows the rlist code to be used for almost any non-interrupt level application.
* 1) Eliminate unnecessary bzero of UPAGES.dyson1996-03-021-2/+4
| | | | | 2) Eliminate unnecessary copying of pages during/after forks. 3) Add user map simplification.
* "out of space" -> "out of swap space".dg1996-01-311-2/+2
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* Eliminated many redundant vm_map_lookup operations for vm_mmap.dyson1996-01-191-28/+38
| | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Fixed 1TB filesize changes. Some pindexes had bogus names and typesbde1995-12-171-3/+3
| | | | but worked because vm_pindex_t is indistinuishable from vm_offset_t.
* Another mega commit to staticize things.phk1995-12-141-13/+25
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* A Major staticize sweep. Generates a couple of warnings that I'll dealphk1995-12-141-14/+1
| | | | | | with later. A number of unused vars removed. A number of unused procs removed or #ifdefed.
* Some new anti-deadlock code ended up messing up the paging stats. A modifieddyson1995-12-111-16/+18
| | | | | version of the code is now in place, and gausspage performance is back up to where it should be.
* Changes to support 1Tb filesizes. Pages are now named by andyson1995-12-111-111/+92
| | | | (object,index) pair instead of (object,offset) pair.
* Untangled the vm.h include file spaghetti.dg1995-12-071-2/+7
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* Completed function declarations and/or added prototypes.bde1995-12-031-8/+28
| | | | | | | | | Staticized some functions. __purified some functions. Some functions were bogusly declared as returning `const'. This hasn't done anything since gcc-2.5. For later versions of gcc, the equivalent is __attribute__((const)) at the end of function declarations.
* Remove unused vars & funcs, make things static, protoize a little bit.phk1995-11-201-2/+1
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* Fixed recent staticizations. Some protypes for static functions werebde1995-11-161-1/+10
| | | | left in headers and not staticized.
* staticize.phk1995-11-141-14/+14
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* Move page fixups (pmap_clear_modify, etc) that happen after paging inputdg1995-11-021-1/+6
| | | | | | | completes out of vm_fault and into the pagers. This get rid of some redundancy and improves the architecture. Reviewed by: John Dyson <dyson>
* Check that the swap block is valid before including it in a cluster.dg1995-09-241-1/+5
| | | | Submitted by: John Dyson
* Make sure that the prezero flag is cleared when needed.dyson1995-09-111-1/+2
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* Fixed a sign reversal problem -- might have cause some Sig-11s thatdyson1995-09-061-3/+3
| | | | people have been seeing.
* Allow the fault code to use additional clustering info from bothdyson1995-09-041-3/+29
| | | | bmap and the swap pager. Improved fault clustering performance.
* 1) Merged swpager structure into vm_object.dg1995-07-161-148/+113
| | | | | | 2) Changed swap_pager internal interfaces to cope w/#1. 3) Eliminated object->copy as we no longer have copy objects. 4) Minor stylistic changes.
* NOTE: libkvm, w, ps, 'top', and any other utility which depends on structdg1995-07-131-304/+199
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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).
* Remove trailing whitespace.rgrimes1995-05-301-4/+4
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* Accessing pages beyond the end of a mapped file results in internaldg1995-05-181-3/+3
| | | | | | | | | | | | | inconsistencies in the VM system that eventually lead to a panic. These changes fix the behavior to conform to the behavior in SunOS, which is to deny faults to pages beyond the EOF (returning SIGBUS). Internally, this is implemented by requiring faults to be within the object size boundaries. These changes exposed another bug, namely that passing in an offset to mmap when trying to map an unnamed anonymous region also results in internal inconsistencies. In this case, the offset is forced to zero. Reviewed by: John Dyson and others
* Changed swap partition handling/allocation so that it doesn'tdg1995-05-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | require specific partitions be mentioned in the kernel config file ("swap on foo" is now obsolete). From Poul-Henning: The visible effect is this: As default, unless options "NSWAPDEV=23" is in your config, you will have four swap-devices. You can swapon(2) any block device you feel like, it doesn't have to be in the kernel config. There is a performance/resource win available by getting the NSWAPDEV right (but only if you have just one swap-device ??), but using that as default would be too restrictive. The invisible effect is that: Swap-handling disappears from the $arch part of the kernel. It gets a lot simpler (-145 lines) and cleaner. Reviewed by: John Dyson, David Greenman Submitted by: Poul-Henning Kamp, with minor changes by me.
* Changed "handle" from type caddr_t to void *; "handle" is several differentdg1995-05-101-2/+2
| | | | types of pointers, and "char *" is a bad choice for the type.
* Another error in the correction for trimming swap allocation fordyson1995-05-071-4/+4
| | | | small objects. (This code needs to be revisited.)
* Fixed a calculation that would once-in-a-while cause the swap_pagerdyson1995-05-071-12/+4
| | | | | | | to emit spurious page outside of object type messages. It is not a fatal condition anyway, so the message will be omitted for release. Also, the code that "clips" the allocation size, associated with the above problem, was fixed.
* New flag: B_PAGING. Added as part of the vn driver hack.dg1995-04-191-3/+3
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* Removed obsolete/unused variable declarations.dg1995-04-161-12/+3
| | | | Removed some extern declarations and included the correct include files.
* Moved some zero-initialized variables into .bss. Made code intended to bedg1995-04-161-3/+1
| | | | called only from DDB #ifdef DDB. Removed some completely unused globals.
* Added a check for wrong object size; print a warning, but deal with itdg1995-03-221-1/+9
| | | | | | | correctly. The warning will tell us that there is a bug somewhere else in sizing the object correctly. Submitted by: John Dyson
* Removed redundant newlines that were in some panic strings.dg1995-03-191-2/+2
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* Clear OBJ_INTERNAL flag for device pager objects and named anonymousdg1995-03-111-1/+2
| | | | objects.
* Various changes from John and myself that do the following:dg1995-03-011-11/+11
| | | | | | | | | | New functions create - vm_object_pip_wakeup and pagedaemon_wakeup that are used to reduce the actual number of wakeups. New function vm_page_protect which is used in conjuction with some new page flags to reduce the number of calls to pmap_page_protect. Minor changes to reduce unnecessary spl nesting. Rewrote vm_page_alloc() to improve readability. Various other mostly cosmetic changes.
* Fixed severely broken printf (arguments out of order, no newline).dg1995-02-251-3/+3
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* Only do object paging_in_progress wakeups if someone is waiting on thisdg1995-02-221-2/+6
| | | | | | condition. Submitted by: John Dyson
* Deprecated remaining use of vm_deallocate. Deprecated vm_allocate_with_dg1995-02-211-3/+5
| | | | | | | | pager(). Almost completely rewrote vm_mmap(); when John gets done with the bottom half, it will be a complete rewrite. Deprecated most use of vm_object_setpager(). Removed side effect of setting object persist in vm_object_enter and moved this into the pager(s). A few other cosmetic changes.
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