src/sys/vm/vnode_pager.c, branch release/2.2.8

Fixed some busy page wakeup problems that resulted in vmopar hangs.

1998-08-16T00:09:07Z

PR: 5731

YAMFC (NFS mmap fixes and minor memory leak plugged)

1997-05-28T18:26:46Z

Reviewed by: Randy Terbush

1. Fix the vm_page_zero_count accounting. This should improve the

1997-03-25T04:54:38Z

performance of the pre-zero loop. 2. Fix madvise. It had a myriad of bugs, including the potential for system crashes. 3. Improve vm_map handling. This is a result of work done by both (Alan Cox) and me. Earlier versions of the map handling code was very unintelligent about map coalescing. 4. Support a working and closer to POSIX mlock. 5. A couple of performance enhancements that came along for the ride, including changing certain bitfields to flags in vm_map. 6. Bring procfs up to date with respect to the changes. This code has been carefully extracted from -current. Reviewed by: David Greenman

Clean up the rundown of the object backing a vnode. This should fix

1996-10-17T02:49:35Z

NFS problems associated with forcible dismounts.

The whole issue of not support VOP_LOCK for VBLK devices should be

1996-09-10T05:28:23Z

rethought. This fixes YET another problem with unmounting filesystems. The root cause is not fixed here, but at least the problem has gone away.

Even though this looks like it, this is not a complex code change.

1996-08-21T21:56:23Z

The interface into the "VMIO" system has changed to be more consistant and robust. Essentially, it is now no longer necessary to call vn_open to get merged VM/Buffer cache operation, and exceptional conditions such as merged operation of VBLK devices is simpler and more correct. This code corrects a potentially large set of problems including the problems with ktrace output and loaded systems, file create/deletes, etc. Most of the changes to NFS are cosmetic and name changes, eliminating a layer of subroutine calls. The direct calls to vput/vrele have been re-instituted for better cross platform compatibility. Reviewed by: davidg

Backed out the recent changes/enhancements to the VM code. The

1996-07-30T03:08:57Z

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 or

1996-07-27T03:24:10Z

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.

Another sweep over the pmap/vm macros, this time with more focus on

1996-05-03T21:01:54Z

the usage. I'm not satisfied with the naming, but now at least there is less bogus stuff around.

Fix the problem that unmounting filesystems that are backed by a VMIO

1996-03-19T05:13:22Z

device have reference count problems. We mark the underlying object ono-persistent, and account for the reference count that the VM system maintainsfor the special device close. This should fix the removable device problem.