[akhaldi] 55833: [NEWCC] A reintegration checkpoint for the NewCC branch, brought to you by Team NewCC. Differences with current ReactOS trunk: * A new memory area type, MEMORY_AREA_CACHE, is added...

Author: akhaldi
Date: Thu Feb 23 12:03:06 2012
New Revision: 55833

URL: http://svn.reactos.org/svn/reactos?rev=55833&view=rev
Log:
[NEWCC]
A reintegration checkpoint for the NewCC branch, brought to you by Team NewCC.

Differences with current ReactOS trunk:

* A new memory area type, MEMORY_AREA_CACHE, is added, which represents a mapped region of
a file. In NEWCC mode, user sections are MEMORY_AREA_CACHE type as well, and obey new
semantics. In non-NEWCC mode, they aren't used.
* A way of claiming a page entry for a specific thread's work is added. Placing the
special SWAPENTRY value MM_WAIT_ENTRY in a page table, or in a section page table should
indicate that memory management code is intended to wait for another thread to make some
status change before checking the state of the page entry again. In code that uses this
convention, a return value of STATUS_SUCCESS + 1 is used to indicate that the caller
should use the MiWaitForPageEvent macro to wait until somebody has change the state of a
wait entry before checking again. This is a lighter weight mechanism than PAGEOPs.
* A way of asking the caller to perform some blocking operation without locks held is
provided. This replaces some spaghettified code in which locks are repeatedly taken and
broken by code that performs various blocking operations. Using this mechanism, it is
possible to do a small amount of non-blocking work, fill in a request, then return
STATUS_MORE_PROCESSING_REQUIRED to request that locks be dropped and the blocking
operation be carried out. A MM_REQUIRED_RESOURCES structure is provided to consumers of
this contract to use to accumulate state across many blocking operations. Several
functions wrapping blocking operations are provided in ntoskrnl/cache/reqtools.c.
* Image section pages are no longer direct mapped. This is done to simplify consolidation
of ownership of pages under the data section system. At a later time, it may be possible
to make data pages directly available to image sections for the same file. This is likely
the only direct performance impact this code makes on non-NEWCC mode.

RMAPs:

* A new type of RMAP entry is introduced, distinguished by RMAP_IS_SEGMENT(Address) of the
rmap entry. This kind of entry contains a pointer to a section page table node in the
Process pointer, which in turn links back to the MM_SECTION_SEGMENT it belongs to.
Therefore, a page belonging only to a segment (that is, a segment page that isn't
mapped) can exist and be evicted using the normal page eviction mechanism in balance.c.
Each of the rmap function has been modified to deal with segment rmaps.
* The low 8 bits of the Address field in a segment rmap denote the entry number in the
generic table node pointed to by Process that points to the page the rmap belongs to. By
combining them, you can determine the file offset the page belongs to.
* In NEWCC mode, MmSharePageEntry/UnsharePageEntry are not used, and instead the page
reference count is used to keep track of the number of mappings of a page, allowing the
last reference expiring to allow the page to be recycled without much intervention. These
are still used in non-NEWCC mode. One change has been made, the count fields have been
narrowed by 1 bit to make room for a dirty bit in SSE entries, needed when a page is
present but unmapped.

Section page tables:

* The section page tables are now implemented using RtlGenericTables. This enables a
fairly compact representation of section page tables without having the existence of a
section object imply 4k of fake PDEs. In addition, each node in the generic table has a
wide file offset that is a multiple of 256 pages, or 1 megabyte total. Besides needing
wide file offsets, the only other visible change caused by the switch to generic tables
for section page tables is the need to lock the section segment before interacting with
the section page table.

Eviction:

* Page eviction in cache sections is accomplished by MmpPageOutPhysicalAddress. In the
case of a shared page, it tries to remove all mappings of the indicated page. If this
process fails at any point, the page will simply be drawn back into the target address
spaces. After succeeding at this, if TRUE has been accumulated into the page's dirty
bit in the section page table, it is written back, and then permanently removed.

NewCC mode:

* NEWCC mode is introduced, which rewrites the file cache to a set of cache stripes
actively mapped, along with unmapped section data.
* NewCC is more authentic in its interpretation of the external interface to the windows
cache than the current cache manager, implementing each of the cache manager functions
according to the documented interface with no preconceived ideas about how anything should
be implemented internally. Cache stripes are implemented on top of section objects, using
the same memory manager paths, and therefore economizing code and complexity. This
replaces a rather complicated system in which pages can be owned by the cache manager and
the memory manager simultaneously and they must cooperate in a fairly sophisticated way to
manage them. Since they're quite interdependent in the current code, modifying either
is very difficult. In NEWCC, they have a clear division of labor and thus can be worked on
independently.
* Several third party filesystems that use the kernel Cc interface work properly using
NEWCC, including matt wu's ext3 driver.
* In contrast with code that tries to make CcInitializeCacheMap and CcUninitializeCacheMap
into a pair that supports reference counting, NEWCC lazily initializes the shared and
private cache maps as needed and uses the presence of a PrivateCacheMap on at least one
file pointing to the SharedCacheMap as an indication that the FILE_OBJECT reference in the
SharedCacheMap should still be held. When the last PrivateCacheMap is discarded,
that's the appropriate time to tear down caching for a specific file, as the
SharedCacheMap data is allowed to be saved and reused. We honor this by making the
SharedCacheMap into a depot for keeping track of the PrivateCacheMap objects associated
with views of a file.

Modified:
    trunk/reactos/ntoskrnl/CMakeLists.txt
    trunk/reactos/ntoskrnl/cache/cachesub.c
    trunk/reactos/ntoskrnl/cache/copysup.c
    trunk/reactos/ntoskrnl/cache/fssup.c
    trunk/reactos/ntoskrnl/cache/lazyrite.c
    trunk/reactos/ntoskrnl/cache/logsup.c
    trunk/reactos/ntoskrnl/cache/mdlsup.c
    trunk/reactos/ntoskrnl/cache/newcc.h
    trunk/reactos/ntoskrnl/cache/pinsup.c
    trunk/reactos/ntoskrnl/cache/section/data.c
    trunk/reactos/ntoskrnl/cache/section/fault.c
    trunk/reactos/ntoskrnl/cache/section/io.c
    trunk/reactos/ntoskrnl/cache/section/newmm.h
    trunk/reactos/ntoskrnl/cache/section/reqtools.c
    trunk/reactos/ntoskrnl/cache/section/sptab.c
    trunk/reactos/ntoskrnl/cache/section/swapout.c
    trunk/reactos/ntoskrnl/cc/fs.c
    trunk/reactos/ntoskrnl/include/internal/mm.h
    trunk/reactos/ntoskrnl/mm/amd64/page.c
    trunk/reactos/ntoskrnl/mm/i386/page.c
    trunk/reactos/ntoskrnl/mm/marea.c
    trunk/reactos/ntoskrnl/mm/mmfault.c
    trunk/reactos/ntoskrnl/mm/mminit.c
    trunk/reactos/ntoskrnl/mm/rmap.c
    trunk/reactos/ntoskrnl/mm/section.c
    trunk/reactos/ntoskrnl/ntoskrnl-generic.rbuild
    trunk/reactos/ntoskrnl/po/poshtdwn.c

[This mail would be too long, it was shortened to contain the URLs only.]

Modified: trunk/reactos/ntoskrnl/CMakeLists.txt
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/CMakeLists.txt?re…

Modified: trunk/reactos/ntoskrnl/cache/cachesub.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/cachesub.c?…

Modified: trunk/reactos/ntoskrnl/cache/copysup.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/copysup.c?r…

Modified: trunk/reactos/ntoskrnl/cache/fssup.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/fssup.c?rev…

Modified: trunk/reactos/ntoskrnl/cache/lazyrite.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/lazyrite.c?…

Modified: trunk/reactos/ntoskrnl/cache/logsup.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/logsup.c?re…

Modified: trunk/reactos/ntoskrnl/cache/mdlsup.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/mdlsup.c?re…

Modified: trunk/reactos/ntoskrnl/cache/newcc.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/newcc.h?rev…

Modified: trunk/reactos/ntoskrnl/cache/pinsup.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/pinsup.c?re…

Modified: trunk/reactos/ntoskrnl/cache/section/data.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/dat…

Modified: trunk/reactos/ntoskrnl/cache/section/fault.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/fau…

Modified: trunk/reactos/ntoskrnl/cache/section/io.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/io.…

Modified: trunk/reactos/ntoskrnl/cache/section/newmm.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/new…

Modified: trunk/reactos/ntoskrnl/cache/section/reqtools.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/req…

Modified: trunk/reactos/ntoskrnl/cache/section/sptab.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/spt…

Modified: trunk/reactos/ntoskrnl/cache/section/swapout.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cache/section/swa…

Modified: trunk/reactos/ntoskrnl/cc/fs.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cc/fs.c?rev=55833…

Modified: trunk/reactos/ntoskrnl/include/internal/mm.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/include/internal/…

Modified: trunk/reactos/ntoskrnl/mm/amd64/page.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/amd64/page.c?r…

Modified: trunk/reactos/ntoskrnl/mm/i386/page.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/i386/page.c?re…

Modified: trunk/reactos/ntoskrnl/mm/marea.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/marea.c?rev=55…

Modified: trunk/reactos/ntoskrnl/mm/mmfault.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/mmfault.c?rev=…

Modified: trunk/reactos/ntoskrnl/mm/mminit.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/mminit.c?rev=5…

Modified: trunk/reactos/ntoskrnl/mm/rmap.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/rmap.c?rev=558…

Modified: trunk/reactos/ntoskrnl/mm/section.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/section.c?rev=…

Modified: trunk/reactos/ntoskrnl/ntoskrnl-generic.rbuild
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ntoskrnl-generic.…

Modified: trunk/reactos/ntoskrnl/po/poshtdwn.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/po/poshtdwn.c?rev…