The flag was mandatory since r209792, where vm_page_grab(9) was
changed to only support the alloc retry semantic.
Suggested and reviewed by: alc
Sponsored by: The FreeBSD Foundation
Unify the 2 concept into a real, minimal, sxlock where the shared
acquisition represent the soft busy and the exclusive acquisition
represent the hard busy.
The old VPO_WANTED mechanism becames the hard-path for this new lock
and it becomes per-page rather than per-object.
The vm_object lock becames an interlock for this functionality:
it can be held in both read or write mode.
However, if the vm_object lock is held in read mode while acquiring
or releasing the busy state, the thread owner cannot make any
assumption on the busy state unless it is also busying it.
Also:
- Add a new flag to directly shared busy pages while vm_page_alloc
and vm_page_grab are being executed. This will be very helpful
once these functions happen under a read object lock.
- Move the swapping sleep into its own per-object flag
The KPI is heavilly changed this is why the version is bumped.
It is very likely that some VM ports users will need to change
their own code.
Sponsored by: EMC / Isilon storage division
Discussed with: alc
Reviewed by: jeff, kib
Tested by: gavin, bapt (older version)
Tested by: pho, scottl
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
to pull vm_param.h was removed. Other big dependency of vm_page.h on
vm_param.h are PA_LOCK* definitions, which are only needed for
in-kernel code, because modules use KBI-safe functions to lock the
pages.
Stop including vm_param.h into vm_page.h. Include vm_param.h
explicitely for the kernel code which needs it.
Suggested and reviewed by: alc
MFC after: 2 weeks
Don't use Maxmem when the amount of memory is meant. Use realmem instead.
Maxmem is not only a MD variable, it represents the highest physical memory
address in use. On systems where memory is sparsely layed-out the highest
memory address and the amount of memory are not interchangeable. Scaling the
AGP aperture based on the actual amount of memory (= realmem) rather than
the available memory (= physmem) makes sure there's consistent behaviour
across architectures.
agp_i810.c:
While arguably the use of Maxmem can be considered correct, replace its use
with realmem anyway. agp_i810.c is specific to amd64, i386 & pc98, which
have a dense physical memory layout. Avoiding Maxmem here is done with an
eye on copy-n-paste behaviour in general and to avoid confusion caused by
using realmem in agp.c and Maxmem in agp_i810.c.
In both cases, remove the inclusion of md_var.h
operations required by GEMified i915.ko. It also attaches to SandyBridge
and IvyBridge CPU northbridges now.
Sponsored by: The FreeBSD Foundation
MFC after: 1 month
scope of the object lock in agp_i810.c. (In this specific case, the scope
of the object lock shouldn't matter, but I don't want to create a bad
example that might be copied to a case where it did matter.)
Reviewed by: kib
This replaces d_mmap() with the d_mmap2() implementation and also
changes the type of offset to vm_ooffset_t.
Purge d_mmap2().
All driver modules will need to be rebuilt since D_VERSION is also
bumped.
Reviewed by: jhb@
MFC after: Not in this lifetime...
- correct format strings
- fill opt_agp.h if AGP_DEBUG is defined
- bring AGP_DEBUG to LINT by mentioning it in NOTES
This should hopefully fix a warning that was...
Found by: Coverity Prevent(tm)
CID: 3676
Tested on: amd64, i386
After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.
This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.
Reviewed by: kib
bumped to 800004 to note the change though userland apps should not be
affected since they use <sys/agpio.h> rather than the headers in
sys/dev/agp.
Discussed with: anholt
Repocopy by: simon
/dev/agpgart and agp_free_res() frees resources like the BAR for the
aperture. Splitting this up lets chipset-specific detach routines
manipulate the aperture during their detach routines without panicing.
MFC after: 1 week
Reviewed by: anholt
This adds a function to agp.c to set the aperture resource ID if it's
not the usual AGP_APBASE. Previously, agp.c had been assuming
AGP_APBASE, which resulted in incorrect agp_info, and contortions by
agp_i810.c to work around it.
This also adds functions to agp.c for default AGP_GET_APERTURE() and
AGP_SET_APERTURE(), which return the aperture resource size and disallow
aperture size changes. Moving to these for our AGP drivers will likely
result in stability improvements. This should fix 855-class aperture
size detection.
Additionally, refuse to attach agp_i810 when some RAM is above 4GB and
the GART can't reference memory that high. This should be very rare.
The correct solution would be bus_dma conversion for agp, which is
beyond the scope of this change. Other AGP drivers could likely use
this change as well.
G33/Q35/Q33 AGP support is also included, but disconnected by default
due to lack of testing.
PR: kern/109724 (855 aperture issue)
Submitted by: FUJIMOTO Kou<fujimoto@j.dendai.ac.jp>
Approved by: re (hrs)
drivers already map sections into KVA as needed anyway. Note that this
will probably break the nvidia driver, but I will coordinate to get that
fixed.
MFC after: 2 weeks
two loops in agp_generic_bind_memory(). As an intended side-effect, all
of the calls to vm_page_wakeup() are now performed with the containing
vm object lock held.
caller to vm_page_grab(). Although this gives VM_ALLOC_ZERO a
different meaning for vm_page_grab() than for vm_page_alloc(), I feel
such change is necessary to accomplish other goals. Specifically, I
want to make the PG_ZERO flag immutable between the time it is
allocated by vm_page_alloc() and freed by vm_page_free() or
vm_page_free_zero() to avoid locking overheads. Once we gave up on
the ability to automatically recognize a zeroed page upon entry to
vm_page_free(), the ability to mutate the PG_ZERO flag became useless.
Instead, I would like to say that "Once a page becomes valid, its
PG_ZERO flag must be ignored."
Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.
Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.
Free approx 86 major numbers with a mostly automatically generated patch.
A number of strategic drivers have been left behind by caution, and a few
because they still (ab)use their major number.
- Fail in agp_alloc_gatt if the aperture size is 0 instead of panicing in
contigmalloc.
Reported by: Bjoern Fischer <bfischer@Techfak.Uni-Bielefeld.DE>
Reviewed by: jhb
MFC after: 1 week
part of the support is that it still assumes one master and one target
where as AGP 3.0 actually supports multiple devices on the bus.
Submitted by: Keith Whitwell <keith@tungstengraphics.com>
Sponsored by: The Weather Channel
