virtual memory reservation and a private pool of memory pages -- by a scheme
based on memory pools.
This allows better utilization of memory because buffers can now be allocated
with a granularity finer than the system's native page size (useful for
filesystems with e.g. 1k or 2k fragment sizes). It also avoids fragmentation
of virtual to physical memory mappings (due to the former fixed virtual
address reservation) resulting in better utilization of MMU resources on some
platforms. Finally, the scheme is more flexible by allowing run-time decisions
on the amount of memory to be used for buffers.
On the other hand, the effectiveness of the LRU queue for buffer recycling
may be somewhat reduced compared to the traditional method since, due to the
nature of the pool based memory allocation, the actual least recently used
buffer may release its memory to a pool different from the one needed by a
newly allocated buffer. However, this effect will kick in only if the
system is under memory pressure.
Add USBVERBOSE, uncomment MIIVERBOSE, sort *VERBOSE.
Add "netbsd-aumac0" config line for root-on-aumac0.
Remove commented out "usb@uhci" device.
Add USB devices from the DB1500 config file.
Add umass/sd.
which is automatically included during kernel config, and add comments
to individual machine-dependant majors.* files to assign new MI majors
in MI file.
Range 0-191 is reserved for machine-specific assignments, range
192+ are MI assignments.
Follows recent discussion on tech-kern@
enabled on amd64). Add a dmat64 field to various PCI attach structures,
and pass it down where needed. Implement a simple new function called
pci_dma64_available(pa) to test if 64bit DMA addresses may be used.
This returns 1 iff _PCI_HAVE_DMA64 is defined in <machine/pci_machdep.h>,
and there is more than 4G of memory.
page: -1 for error, 0 for EOF, 1 otherwise. Inspired by an OpenBSD commit
message, pointed out by Miod Vallat in private mail.
vax/mba/hp.c: check return value <= 0, not < 0 to be concistent with how
other places handle return values from bounds_check_with_label().
cd ${KERNSRCDIR}/${KERNARCHDIR}/compile && ${PRINTOBJDIR}
This is far simpler than the previous system, and more robust with
objdirs built via BSDOBJDIR.
The previous method of finding KERNOBJDIR when using BSDOBJDIR by
referencing _SRC_TOP_OBJ_ from another directory was extremely
fragile due to the depth first tree walk by <bsd.subdir.mk>, and
the caching of _SRC_TOP_OBJ_ (with MAKEOVERRIDES) which would be
empty on the *first* pass to create fresh objdirs.
This change requires adding sys/arch/*/compile/Makefile to create
the objdir in that directory, and descending into arch/*/compile
from arch/*/Makefile. Remove the now-unnecessary .keep_me files
whilst here.
Per lengthy discussion with Andrew Brown.
pk