- Designed to be fully MP-safe and highly efficient.
- Tables/IP sets (hash or red-black tree) for high performance lookups.
- Stateful filtering and Network Address Port Translation (NAPT).
Framework for application level gateways (ALGs).
- Packet inspection engine called n-code processor - inspired by BPF -
supporting generic RISC-like and specific CISC-like instructions for
common patterns (e.g. IPv4 address matching). See npf_ncode(9) manual.
- Convenient userland utility npfctl(8) with npf.conf(8).
NOTE: This is not yet a fully capable alternative to PF or IPFilter.
Further work (support for binat/rdr, return-rst/return-icmp, common ALGs,
state saving/restoring, logging, etc) is in progress.
Thanks a lot to Matt Thomas for various useful comments and code review.
Aye by: board@
also known as C-states. The code is modular and provides an easy way to add
the remaining functionality later (namely throttling and P-states).
Remarks:
1. Commented out in the GENERICs; more testing exposure is needed.
2. The C3-state is disabled for the time being because it turns off
timers, among them the local APIC timer. This may not be universally
true on all x86 processors; define ACPICPU_ENABLE_C3 to test.
3. The algorithm used to choose a power state may need tuning. When
evaluating the appropriate state, the implementation uses the
previous sleep time as an indicator. Additional hints would include
for example the system load.
Also bus master activity is evaluated when choosing a state. The
usb(4) stack is notorious for such activity even when unused.
Typically it must be disabled in order to reach the C3-state,
but it may also prevent the use of C2.
4. While no extensive empirical measurements have been carried out, the
power savings are somewhere between 1-2 W with C1 and C2, depending
on the processor, firmware, and load. With C3 even up to 4 W can be
saved. The less something ticks, the more power is saved.
ok jmcneill@, joerg@, and discussed with various people.
These annotations help to mitigate false sharing on multiprocessor
systems.
Variables annotated with __cacheline_aligned are placed into the
.data.cacheline_aligned section in the kernel. Each item in this
section is aligned on a cachline boundary - this avoids false
sharing. Highly contended global locks are a good candidate for
__cacheline_aligned annotation.
Variables annotated with __read_mostly are packed together tightly
into a .data.read_mostly section in the kernel. The idea here is that
we can pack infrequently modified data items into a cacheline and
avoid having to purge the cache, which would happen if read mostly
data and write mostly data shared a cachline. Initialisation variables
are a prime candiate for __read_mostly annotations.
canonicalise several of the ipf option segments in various files
(this mostly means adding commented out IPFILTER_DEFAULT_BLOCK,
or adding commented or uncommented IPFILTER_LOG or IPFILTER_LOOKUP
option statements.)
i built about 20 of these kernels to check, but not all of them.
Thanks to apb@ and cegger@ for initial testing.
XXX: This conflicts with hpqlb(4). Someone with the suitable hardware needs
to complete the list of hotkeys before -- and if -- this can replace
hpqlb(4). For now, the driver was left uncommented in the GENERICs.
Import acpiwmi(4) from Jukka Ruohonen. From the PR:
Attached is a driver that implements ACPI WMI API:
http://www.microsoft.com/whdc/system/pnppwr/wmi/wmi-acpi.mspx
The WMI is used to provide a generic interface for OEMs to use certain
platform/laptop-specific additions to the standard ACPI in a somewhat
portable way. These can be hotkeys for additional buttons, different event
handlers (wireless kill switch, lid switch, etc.), and so on. At least HP
and Acer use it by default nowadays.
The benefit of this interface would be portability. For an example, instead
of hpqlb(4) that works only with certain HP models, we could have a generic
HP WMI-driver that should work in theory across all HP laptops. On many new
laptops WMI may also be the only way to access laptop/manufacturer-specific
features.
It will replace azalia(4) after testing.
To use, comment out azalia in your kernel configuration and uncomment the
hdaudio and hdafg lines so it reads:
# Intel High Definition Audio
hdaudio* at pci? dev ? function ?
hdafg* at hdaudiobus?
You should also:
cd /dev
sh MAKEDEV audio
