defconfig: updated i9305 defconfig

Change-Id: If5a2e70939234eb47f04c8195fa7c9df8a07bbb5
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
defconfig: set ROW as default scheduler

Change-Id: I829d3fd117bdec32dee0e5b25feeb19b32c5456f
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
defconfig: Enabled interactive and conservative CPU governors

The code for interactive and conservative is already implemented into the kernel, so I might as well enable them.
The exception is adaptive, who is causing all sorts of issues, including spontaneous reboots (esp. in recovery)
due to hung task timeouts on basically any device that doesn't have it set to default.

Change-Id: I9ac7b2f65ba95ae41eac153d657e91ebba96ad21
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
cpufreq_conservative: Improve support for micro idle accounting

The minimum samplerate calculations of the current conservative
implementation assume that there is not micro idle accounting present,
however, we do have that capability in our idle estimates.  As a result,
we can support lower polling intervals just like ondemand does.

Change-Id: I134027f28abd8e76ee8212685572272b1ddaa872
Signed-off-by: Andrew Dodd <atd7@cornell.edu>
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
defconfig: Enabled Asynchronous I/O (AIO)

Change-Id: I7c4a5606d0aa62af3288660f280aa1cb76eb1756
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
sched: LOAD_FREQ (4*HZ+61) avoids loadavg Moire

LOAD_FREQ is (5*HZ+1) to avoid high load average when idle:
http://kerneltrap.org/mailarchive/linux-kernel/2007/10/3/328568

I suggest (4*HZ+61) for a better distribution.

With some seconds based load (like SSL heartbeats)
and LOAD_FREQ at (5*HZ+1) I see Moire patterns like inverse sawtooth,
since 2 or 3 probes hit the jobs (load increases quickly),
followed by several probes missing it.

A 4.61 sec interval gives optimal distribution over when within a
second a probe is taken, as .61 is close to golden ratio phi 1.618...
(test in http://ripke.com/goldenratio.c).

12*4.61 = 55.32 secs is still close to a minute,
and 13*4.61=59.93 is even closer than the current 12*5.01=60.12
(with exponents EXP_x adjusted to a ratio of 13 instead of 12).

See http://ripke.com/loadavg/moire for details.

Change-Id: Ic637bbf92c5c7105cb5bddaff54a340401e3f5e2
Signed-off-by: zwliew <zhaoweiliew@gmail.com>
AIO: Don't plug the I/O queue in do_io_submit() Asynchronous I/O latency to a solid-state disk greatly increased between the 2.6.32 and 3.0 kernels. By removing the plug from do_io_submit(), we observed a 34% improvement in the I/O latency.

Unfortunately, at this level, we don't know if the request is to
a rotating disk or not.

Change-Id: I7101df956473ed9fd5dcff18e473dd93b688a5c1
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: linux-aio@kvack.org
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: zwliew <zhaoweiliew@gmail.com>

Conflicts:
	fs/aio.c