It seems that on process killing, some VACB may be deleted while
still mapped. With current reference counting, they will actually
not be deleted, but leaked, and an ASSERT will be triggered.
CORE-14578
This has have several benefits for ReactOS Cc:
- It helps reducing potential deadlocks situations in Cc
- It speeds up ReactOS by reducing locks
- It gets us a bit closer to Windows VACB
CORE-14349
The avoids race conditions where attempts to read from disk to
not fully initialized VACB were performed.
Also, added more debug prints in such situations.
CORE-14349
This allows being consistent between newly created and looked up
so that VACB can always safely be released.
Should really help with reference issues.
CORE-14481
CORE-14480
CORE-14482
This fixes various bugs linked to VACB counting:
- VACB not released when it should be
- Reference count expectations not being accurate
For the record, VACB should always have at least a reference
count of 1, unless you are to free it and removed it from
any linked list.
This commit also adds a bunch of asserts that should
help triggering invalid reference counting.
It should also fix numerous ASSERT currently triggered and
may help fixing random behaviours in Cc.
CORE-14285
CORE-14401
CORE-14293
Standard shared cache map provides space for a private cache map, do the same
and make it available for the first handle. It avoids two allocations in a row.
This halfplements CcScheduleReadAhead() which is responsible for finding the next reads
to perform given last read and previous reads. I made it very basic for now, at least
to test the whole process.
This also introduces the CcExpressWorkQueue in the lazy writer which is responsible
for dealing with read ahead items and which is dealt with before the regular queue.
In CcCopyData(), if read was fine, schedule read ahead so that it can happen in background
without the FSD to notice it! Also, update the read history so that scheduling as a
bit of data.
Implement (à la "old Cc" ;-)) CcPerformReadAhead() which is responsible for performing
the read. It's only to be called by the worker thread.
Side note on the modifications done in CcRosReleaseFileCache(). Private cache map
is tied to a handle. If it goes away, private cache map gets deleted. Read ahead
can run after the handle was closed (and thus, private cache map deleted), so
it is mandatory to always lock the master lock before accessing the structure in
read ahead or before deleting it in CcRosReleaseFileCache(). Otherwise, you'll
just break everything. You've been warned!
This commit also partly reverts f8b5d27.
CORE-14312
before the call to CcRosReleaseFileCache() which expects to have it to properly clean the file.
So, move deletion code to CcRosReleaseFileCache() so that he's the only one to handle private map.
Should hopefully fix all the recent buildbots issues (and the universe perhaps, who knows?)
This reverts BCB being lazy written when marked dirty.
We'll go back to this behavior when this part will have been reworked and stabilized.
CORE-14263
CORE-14279
CORE-14285
Instead move to a threading model like the Windows one.
We'll queue several work items to be executed in a system thread (Cc worker)
when there are VACB that have been marked as dirty. Furthermore, some delay
will be observed before action to avoid killing the system with IOs.
This new threading model opens way for read ahead and write behind implementation.
Also, moved the initialization of the lazy writer to CcInitializeCacheManager()
it has nothing to do with views and shouldn't be initialized there.
Also, moved the lazy writer implementation to its own file.
Modified CcDeferWrite() and CcRosMarkDirtyVacb() to take into account the new threading model.
Introduced new functions:
- CcPostWorkQueue(): post an item to be handled by Cc worker and spawn a worker if required
- CcScanDpc(): called after some time (not to have lazy writer always running) to queue a lazy scan
- CcLazyWriteScan(): the lazy writer we used to have
- CcScheduleLazyWriteScan(): function to call when you want to start a lazy writer run. It will make a DPC after some time and queue execution
- CcWorkerThread(): the worker thread that will handle lazy write, read ahead, and so on
- CcUnpinDataForThread() only release VACB when the last BCB reference is gone. This avoids having a valid BCB with an invalid VACB
- CcRosMarkDirtyVacb() will only accept non-dirty VACB now. This avoids a major bug where a an already dirty VACB was over-dereferenced
- Thanks to previous point, simplify CcRosUnmapVacb(), CcRosReleaseVacb() implementation
- And only set VACB dirty once in CcSetDirtyPinnedData()
- Add a few sanity checks
With that I can again install ReactOS with 128MB RAM :-).
CORE-14263
CORE-14268
Namely, implement CcSetDirtyPageThreshold() and add support for it
in CcCanIWrite().
Also added my name in the headers of the few files I touched tonight.
CORE-14235