"debug.mpsafevm" results in (almost) Giant-free execution of zero-fill
page faults. (Giant is held only briefly, just long enough to determine
if there is a vnode backing the faulting address.)
Also, condition the acquisition and release of Giant around calls to
pmap_remove() on "debug.mpsafevm".
The effect on performance is significant. On my dual Opteron, I see a
3.6% reduction in "buildworld" time.
- Use atomic operations to update several counters in vm_fault().
before dereferencing sotounpcb() and checking its value, as so_pcb
is protected by protocol locking, not subsystem locking. This
prevents races during close() by one thread and use of ths socket
in another.
unp_bind() now assert the UNP lock, and uipc_bind() now acquires
the lock around calls to unp_bind().
wait for system wires to disappear, do so (much more trivially) by
instead only checking for system wires of user maps and not kernel maps.
Alternative by: tor
Reviewed by: alc
o Update to match 5-CURRENT reality.
o Bump up minimum system requirements.
o Make examples work.
PR: docs/70485
Submitted by: Gavin Atkinson <gavin.atkinson@ury.york.ac.uk>
- pipespace is now able to resize non-empty pipes; this allows
for many more resizing opportunities
- Backing is no longer pre-allocated for the reverse direction
of pipes. This direction is rarely (if ever) used, so this cuts the
amount of map space allocated to a pipe in half.
- Pipe growth is now much more dynamic; a pipe will now grow when
the total amount of data it contains and the size of the write are
larger than the size of pipe. Previously, only individual writes greater
than the size of the pipe would cause growth.
- In low memory situations, pipes will now shrink during both read
and write operations, where possible. Once the memory shortage
ends, the growth code will cause these pipes to grow back to an appropriate
size.
- If the full PIPE_SIZE allocation fails when a new pipe is created, the
allocation will be retried with SMALL_PIPE_SIZE. This helps to deal
with the situation of a fragmented map after a low memory period has
ended.
- Minor documentation + code changes to support the above.
In total, these changes increase the total number of pipes that
can be allocated simultaneously, drastically reducing the chances that
pipe allocation will fail.
Performance appears unchanged due to dynamic resizing.
Decrease log severity to debug if a protocol is not supported by the
kernel (rpcbind checks /etc/netconfig if a protocol is available).
This avoids "rpcbind: cannot create socket for tcp6" messages
at startup on IPv4-only kernels.
for EBus, ISA and PCI, by compiling ofw_isa.c and ofw_pci_if.m unconditio-
nally. The correct way is to rewrite OF_decode_addr() in ofw_machdep.c in
a bus-neutral way. That's certainly possible but we unfortunately didn't
make it for FreeBSD 5.3.
Approved by: tmm
meaningless. In particular, don't assume that it is left untouched if
stat(2) fails; that assumption happens to fail at high optimization
levels on some platforms.
MFC after: 1 week
contained "sanity" checks that could be violated if another CPU modified
the pmap between the emulation trap and locking the pmap in
pmap_emulate_reference(). As a result, the pte could be inconsistent
with the access that caused the emulation trap. In such cases,
pmap_emulate_reference() now flushes the current CPU's TLB entry and
returns.
- Make pmap_changebit() an inline function, reducing object code size.
- Add the manufacturer name to each item in the device list.
- Make the note about supporting "IBM e335" into a general list and
change the entry to use the full product name ("IBM eServer xSeries
335").
- Add Dell PowerEdge 1750 to the list of systems with mpt onboard.
use it, only those with FCode. Add references to dc(4), gem(4) and hme(4)
for obtaining further information about such devices presently supported
by FreeBSD.
- Correct the HISTORY section. There was an eeprom(8) utility in 4.4BSD and
early versions of FreeBSD 2.x.
- Add an AUTHORS section.
