as argument passed by value' trick, as gcc 3.3.x makes (valid) assumptions
about the stack that will not be true. Costs 2 instructions per trap/syscall
on i386, 4 per interrupt for MP. One instruction per trap/syscall on amd64,
2 per interrupt for MP. I expect gcc 3.3.1 to make up for this by better
optimization (it'd better..)
While here, make amd64 compile again by using subr_mbr_disk.c
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.
Bump the kernel rev up to 1.6V
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.
routing to follow later) if the ACPI implementation is marked as
having a quirky PCI bus/interrupt configuration. If MPBIOS is also
defined, it'll do the job instead.
isa_dmamap_create() calls to their open/close entrypoints. This worked
with some luck, but broke on i386 when _bus_dmamap_create started
to allocate bounce buffers upfront, since memory below 16M may well
not be available when the sound devices is opened for the Nth time.
To fix this, create a new simple interface, isa_drq_alloc/isa_drq_free,
wrappers around already existing bitmask macros. These are expected
to be used before an isa_dmamap_create call, and after an
isa_dmamap_destroy call, respectively. For the sb and ad1848 drivers,
they're deferred until open/close.
All isa_dmamap_create calls can now use BUS_DMA_ALLOCNOW and be done
at attach time.
Make ALLOCNOW the default iff bouncing might be needed (this has
no effect on i386 because ISA DMA devices already had to use
ALLOCNOW, and PCI isn't bounced (yet), since we don't do > 4G
at this point for i386.
extended disk information request to the kernel.
Binary compatible with the existing code, disabled because I don't
have a system with a bios that supports the request.
to extract the physical address from the virtual.
On the ARM, also use the "read-only at MMU" indication to avoid a
redundant cache clean operation.
Other platforms should use these two as examples of how to use these
new pool/mbuf features to improve network performance. Note this requires
a platform to provide a working POOL_VTOPHYS().
Part 3 in a series of simple patches contributed by Wasabi Systems
to improve network performance.