linux/include
Frederic Weisbecker a831881be2 nohz: Basic full dynticks interface
For extreme usecases such as Real Time or HPC, having
the ability to shutdown the tick when a single task runs
on a CPU is a desired feature:

* Reducing the amount of interrupts improves throughput
for CPU-bound tasks. The CPU is less distracted from its
real job, from an execution time and from the cache point
of views.

* This also improve latency response as we have less critical
sections.

Start with introducing a very simple interface to define
full dynticks CPU: use a boot time option defined cpumask
through the "nohz_extended=" kernel parameter. CPUs that
are part of this range will have their tick shutdown
whenever possible: provided they run a single task and
they don't do kernel activity that require the periodic
tick. These details will be later documented in
Documentation/*

An online CPU must be kept outside this range to handle the
timekeeping.

Suggested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-03-21 15:38:33 +01:00
..
acpi Merge branch 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac 2013-02-28 20:42:33 -08:00
asm-generic ImgTec Meta architecture changes for v3.9-rc1 2013-03-03 12:06:09 -08:00
clocksource ImgTec Meta architecture changes for v3.9-rc1 2013-03-03 12:06:09 -08:00
crypto
drm drm: Add HDMI infoframe helpers 2013-02-22 08:20:10 +01:00
keys
linux nohz: Basic full dynticks interface 2013-03-21 15:38:33 +01:00
math-emu
media [media] media: ov7670: Add possibility to disable pixclk during hblank 2013-02-08 14:35:06 -02:00
memory
misc
net Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-03-03 13:23:03 -08:00
pcmcia
ras edac: add support for error type "Info" 2013-02-21 14:16:27 -03:00
rdma IB/core: Add "type 2" memory windows support 2013-02-21 11:51:45 -08:00
rxrpc
scsi SCSI for-linus on 20130301 2013-03-02 11:42:16 -08:00
sound arm-soc: late OMAP changes 2013-02-28 20:00:40 -08:00
target target: Rename spc_get_write_same_sectors -> sbc_get_write_same_sectors 2013-02-23 12:46:14 -08:00
trace Various bug fixes for ext4. The most important is a fix for the new 2013-03-02 19:33:21 -08:00
uapi UAPI disintegration 2012-12-20 2013-03-03 14:24:59 -08:00
video UAPI disintegration 2012-12-20 2013-03-03 14:24:59 -08:00
xen xen: event channel arrays are xen_ulong_t and not unsigned long 2013-02-20 08:45:07 -05:00
Kbuild