hardclock() tick should be run on every active CPU, or on only one.
On my tests, avoiding extra interrupts because of this on 8-CPU Core i7
system with HZ=10000 saves about 2% of performance. At this moment option
implemented only for global timers, as reprogramming per-CPU timers is
too expensive now to be compensated by this benefit, especially since we
still have to regularly run hardclock() on at least one active CPU to
update system uptime. For global timer it is quite trivial: timer runs
always, but we just skip IPIs to other CPUs when possible.
Option is enabled by default now, keeping previous behavior, as periodic
hardclock() calls are still used at least to implement setitimer(2) with
ITIMER_VIRTUAL and ITIMER_PROF arguments. But since default schedulers don't
depend on it since r232917, we are much more free to experiment with it.
MFC after: 1 month
Winbond Super I/O chips.
With minor efforts it should be possible the extend the driver to support
further chips/revisions available from Winbond. In the simplest case
only new IDs need to be added, while different chipsets might require
their own function to enter extended function mode, etc.
Sponsored by: Sandvine Incorporated ULC (in 2011)
Reviewed by: emaste, brueffer
MFC after: 2 weeks
interface supported by mvs(4) are 88SX, while AHCI-like chips are 88SE.
PR: kern/165271
Submitted by: Jia-Shiun Li <jiashiun@gmail.com>
MFC after: 1 week
USERSPACE:
1. add support for devices with different number of rx and tx queues;
2. add better support for zero-copy operation, adding an extra field
to the netmap ring to indicate how many buffers we have already processed
but not yet released (with help from Eddie Kohler);
3. The two changes above unfortunately require an API change, so while
at it add a version field and some spares to the ioctl() argument
to help detect mismatches.
4. update the manual page for the two changes above;
5. update sample applications in tools/tools/netmap
KERNEL:
1. simplify the internal structures moving the global wait queues
to the 'struct netmap_adapter';
2. simplify the functions that map kring<->nic ring indexes
3. normalize device-specific code, helps mainteinance;
4. start exploring the impact of micro-optimizations (prefetch etc.)
in the ixgbe driver.
Use 'legacy' descriptors on the tx ring and prefetch slots gives
about 20% speedup at 900 MHz. Another 7-10% would come from removing
the explict calls to bus_dmamap* in the core (they are effectively
NOPs in this case, but it takes expensive load of the per-buffer
dma maps to figure out that they are all NULL.
Rx performance not investigated.
I am postponing the MFC so i can import a few more improvements
before merging.
- Remove all attempts to guess physical temperature using DiodeOffset.
There are too many reports that it varies wildly depending on motherboard.
Instead, if it is known to scale well and its offset is known from other
temperature sensors on board, the user may set "dev.amdtemp.0.sensor_offset"
tunable to compensate the difference. Document the caveats in amdtemp(4).
- Add a quirk for Socket AM2 Revision G processors. These processors are
known to have a different offset according to Linux k8temp driver.
- Warn about Family 10h Erratum 319. These processors have broken sensors.
- Report temperature in more logical orders under dev.amdtemp node. For
example, "dev.amdtemp.0.sensor0.core0" is now "dev.amdtemp.0.core0.sensor0".
- Replace K8, K10 and K11 with official processor names in amdtemp(4).
- Convert to our standard SYNOPSIS language
- Consistently use "The .Nm driver"
- Rewrite .nf .fi block with mdoc
- Add pci dependency to SYNOPSIS
- Start .Bl list with new paragraph
Approved by: luigi
The reasoning behind this, is that if we are consistent in our
documentation about the uint*_t stuff, people will be less tempted to
write new code that uses the non-standard types.
I am not going to bump the man page dates, as these changes can be
considered style nits. The meaning of the man pages is unaffected.
MFC after: 1 month
This should have been included in change 230592.
The supported hardware section still needs some updating to reflect
the current reality.
MFC after: 3 days
TCP_KEEPCNT, that allow to control initial timeout, idle time, idle
re-send interval and idle send count on a per-socket basis.
Reviewed by: andre, bz, lstewart
The isci driver is for the integrated SAS controller in the Intel C600
(Patsburg) chipset. Source files in sys/dev/isci directory are
FreeBSD-specific, and sys/dev/isci/scil subdirectory contains
an OS-agnostic library (SCIL) published by Intel to control the SAS
controller. This library is used primarily as-is in this driver, with
some post-processing to better integrate into the kernel build
environment.
isci.4 and a README in the sys/dev/isci directory contain a few
additional details.
This driver is only built for amd64 and i386 targets.
Sponsored by: Intel
Reviewed by: scottl
Approved by: scottl
