gitignore: add auto generated files

Signed-off-by: Blechd0se <alex.christ@hotmail.de>
misc: add dynamic writeback interface

Before this patch, the deamon for flushing
dirty pages kicks in every 600 ms. This patch
changes the behaviour a little bit. While suspended
it flushes more pages (every 500 ms) and while the
the device is awake and in use it flushes only every
4 s to gain a little performance boost.

This is fully controllable;

echo 1 > /sys/devices/virtual/misc/writeback/writeback_enabled
(1 = On (default), 0 = off (and behaviour before this
patch).

Signed-off-by: Blechd0se <alex.christ@hotmail.de>
AIO: Don't plug the I/O queue in do_io_submit() Asynchronous I/O late…
…ncy 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: Blechd0se <alex.christ@hotmail.de>