freebsd-nq/sys/mips
Attilio Rao 89f6b8632c Switch the vm_object mutex to be a rwlock. This will enable in the
future further optimizations where the vm_object lock will be held
in read mode most of the time the page cache resident pool of pages
are accessed for reading purposes.

The change is mostly mechanical but few notes are reported:
* The KPI changes as follow:
  - VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK()
  - VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK()
  - VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK()
  - VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED()
    (in order to avoid visibility of implementation details)
  - The read-mode operations are added:
    VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(),
    VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED()
* The vm/vm_pager.h namespace pollution avoidance (forcing requiring
  sys/mutex.h in consumers directly to cater its inlining functions
  using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h
  consumers now must include also sys/rwlock.h.
* zfs requires a quite convoluted fix to include FreeBSD rwlocks into
  the compat layer because the name clash between FreeBSD and solaris
  versions must be avoided.
  At this purpose zfs redefines the vm_object locking functions
  directly, isolating the FreeBSD components in specific compat stubs.

The KPI results heavilly broken by this commit.  Thirdy part ports must
be updated accordingly (I can think off-hand of VirtualBox, for example).

Sponsored by:	EMC / Isilon storage division
Reviewed by:	jeff
Reviewed by:	pjd (ZFS specific review)
Discussed with:	alc
Tested by:	pho
2013-03-09 02:32:23 +00:00
..
adm5120 Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
alchemy Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
atheros Mips Atheros AR71XX: make PCI base slot configurable through hints. 2013-01-06 20:50:31 +00:00
beri Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
cavium Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
compile
conf Add basic support for the Ubiquiti EdgeRouter Lite. 2013-01-02 23:17:50 +00:00
gxemul Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
idt Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
include Define VM_KMEM_SIZE_MAX as a fraction of the kernel address space size 2013-01-12 18:06:21 +00:00
malta Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
mips Switch the vm_object mutex to be a rwlock. This will enable in the 2013-03-09 02:32:23 +00:00
nlm MFcalloutng: 2013-02-28 13:46:03 +00:00
rmi MFcalloutng: 2013-02-28 13:46:03 +00:00
rt305x Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
sentry5 Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00
sibyte Merge from vmobj-rwlock branch: 2013-02-26 01:00:11 +00:00