to handle current timecounter wraps. Make kern_clocksource.c to honor that
requirement, scheduling sleeps on first CPU for no more then specified
period. Allow other CPUs to sleep up to 1/4 second (for any case).
Do not explicitly enable interrupts in smp_init_secondary() because it
renders any spinlock protected code after that point to run with
interrupts enabled. This is because the processor is executing in the
context of idlethread whose 'md_spinlock_count' is already set to 1.
Instead just let sched_throw() re-enable interrupts when it releases
the spinlock.
The original powerpc commit log for r212559 is available here:
http://svn.freebsd.org/viewvc/base?view=revision&revision=212559
when the original offset is bigger than size of one page. X86BIOS macros
cannot be used here because it is assumed address is only linear in a page.
Tested by: netchild
The $ip6addrctl_policy is a variable to choose a pre-defined address
selection policy set by ip6addrctl(8).
The keyword "ipv4_prefer" sets IPv4-preferred one described in Section 10.3,
the keyword "ipv6_prefer" sets IPv6-preferred one in Section 2.1 in RFC 3484,
respectively. When "AUTO" is specified, it attempts to read
/etc/ip6addrctl.conf first. If it is found, it reads and installs it as
a policy table. If not, either of the two pre-defined policy tables is
chosen automatically according to $ipv6_activate_all_interfaces.
When $ipv6_activate_all_interfaces=NO, interfaces which have no corresponding
$ifconfig_IF_ipv6 is marked as IFDISABLED for security reason.
The default values are ip6addrctl_policy=AUTO and
ipv6_activate_all_interfaces=NO.
Discussed with: ume and bz
unexpected things in copyout(9) and so wiring the user buffer is not
sufficient to perform a copyout(9) while holding a random mutex.
Requested by: nwhitehorn
'makeoptions OPTION=' for consistency with the make commandline.
Previously 'makeoptions WERROR=' would result in a syntax error; now
it produces the same effect as 'makeoptions WERROR'. Both forms now
result in 'WERROR=' in the generated Makefile.
any spin locks acquired between the enabling of interrupts in
machdep_ap_bootstrap() and the invocation of the scheduler would fail to
have interrupts disabled due to the fake spinlock already held by the
idle thread. sched_throw(NULL) will enable interrupts by itself when
exiting this spinlock, so just let it do that and don't enable interrupts
here.
allow the option to be specified multiple times. This will help to
implement things like passing multiple keyfiles to geli(8) instead of
cat(1)ing them all into stdin and reading from there using one '-k -'
option.
understand everything correctly, we don't really need it.
- Provide default numeric value as strings. This allows to simplify
a lot of code.
- Bump version number.
- Remove sync from msgrng_send, sync needs to be called just once before
sending.
- Fix retry logic - don't reload registers when retrying in message_send,
also fix check for send pending fail.
- remove unused message_send_block_fast()
- merge message_receive_fast() to message_receive
- style(9) fixes, and comments
- rge and nlge updated for the sys/mips/rmi/msgring.h changes
ACPI specification sates that if P_LVL2_LAT > 100, then a system doesn't
support C2; if P_LVL3_LAT > 1000, then C3 is not supported.
But there are no such rules for Cx state data returned by _CST. If a
state is not supported it should not be included into the return
package. In other words, any latency value returned by _CST is valid,
it's up to the OS and/or user to decide whether to use it.
Submitted by: nork
Suggested by: mav
MFC after: 1 week
If a kobj method doesn't have any explicitly provided default
implementation, then it is auto-assigned kobj_error_method.
kobj_error_method is proper only for methods that return error code,
because it just returns ENXIO.
So, in the case of unimplemented bus_add_child caller would get
(device_t)ENXIO as a return value, which would cause the mistake to go
unnoticed, because return value is typically checked for NULL.
Thus, a specialized null_add_child is added. It would have sufficied
for correctness to return NULL, but this type of mistake was deemed to
be rare and serious enough to call panic instead.
Watch out for this kind of problem with other kobj methods.
Suggested by: jhb, imp
MFC after: 2 weeks
The main goal of this is to generate timer interrupts only when there is
some work to do. When CPU is busy interrupts are generating at full rate
of hz + stathz to fullfill scheduler and timekeeping requirements. But
when CPU is idle, only minimum set of interrupts (down to 8 interrupts per
second per CPU now), needed to handle scheduled callouts is executed.
This allows significantly increase idle CPU sleep time, increasing effect
of static power-saving technologies. Also it should reduce host CPU load
on virtualized systems, when guest system is idle.
There is set of tunables, also available as writable sysctls, allowing to
control wanted event timer subsystem behavior:
kern.eventtimer.timer - allows to choose event timer hardware to use.
On x86 there is up to 4 different kinds of timers. Depending on whether
chosen timer is per-CPU, behavior of other options slightly differs.
kern.eventtimer.periodic - allows to choose periodic and one-shot
operation mode. In periodic mode, current timer hardware taken as the only
source of time for time events. This mode is quite alike to previous kernel
behavior. One-shot mode instead uses currently selected time counter
hardware to schedule all needed events one by one and program timer to
generate interrupt exactly in specified time. Default value depends of
chosen timer capabilities, but one-shot mode is preferred, until other is
forced by user or hardware.
kern.eventtimer.singlemul - in periodic mode specifies how much times
higher timer frequency should be, to not strictly alias hardclock() and
statclock() events. Default values are 2 and 4, but could be reduced to 1
if extra interrupts are unwanted.
kern.eventtimer.idletick - makes each CPU to receive every timer interrupt
independently of whether they busy or not. By default this options is
disabled. If chosen timer is per-CPU and runs in periodic mode, this option
has no effect - all interrupts are generating.
As soon as this patch modifies cpu_idle() on some platforms, I have also
refactored one on x86. Now it makes use of MONITOR/MWAIT instrunctions
(if supported) under high sleep/wakeup rate, as fast alternative to other
methods. It allows SMP scheduler to wake up sleeping CPUs much faster
without using IPI, significantly increasing performance on some highly
task-switching loads.
Tested by: many (on i386, amd64, sparc64 and powerc)
H/W donated by: Gheorghe Ardelean
Sponsored by: iXsystems, Inc.
costs us another copy of the transform. Revert it.
# Maybe makefile.inc1 should set TARGET_CPUARCH for the cross-tools, but
# it doesn't now. That would solve problems in other places too.
Submitted by: jmallet@
