KGSL: Add a simple GPU governor for Adreno xxx GPU series

initial coding for a Simple GPU governor based on my own work 2 years ago
from Sensation GB kernel commit: c1ea8f64167270d67915b4d4fb00910b1c0f513f

Signed-off-by: Paul Reioux <reioux@gmail.com>
KGSL: make simple govenor a selectable option, co-exist with ondemand

also removed some hardcoded values

Signed-off-by: Paul Reioux <reioux@gmail.com>
KGSL: simple governor: expose tunables to sysfs interface via module_param

Signed-off-by: Paul Reioux <reioux@gmail.com>
KGSL: Simple Governor: fix minor logic issue

Signed-off-by: Paul Reioux <reioux@gmail.com>
enable simple gov
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>
msm: Allow lowmem to be non contiguous and mixed.

Any image that is expected to have a lifetime of
the entire system can give the virtual address
space back for use in vmalloc.

Change-Id: I81ce848cd37e8573d706fa5d1aa52147b3c8da12
Signed-off-by: Neeti Desai <neetid@codeaurora.org>
swap: allow swap readahead to be merged

Swap readahead works fine, but the I/O to disk is almost always done in
page size requests, despite the fact that readahead submits
1<<page-cluster pages at a time.

On older kernels the old per device plugging behavior might have captured
this and merged the requests, but currently all comes down to much more
I/Os than required.

On a single device this might not be an issue, but as soon as a server
runs on shared san resources savin I/Os not only improves swapin
throughput but also provides a lower resource utilization.

With a load running KVM in a lot of memory overcommitment (the hot memory
is 1.5 times the host memory) swapping throughput improves significantly
and the lead feels more responsive as well as achieves more throughput.

In a test setup with 16 swap disks running blocktrace on one of those disks
shows the improved merging:
Prior:
Reads Queued:     560,888,    2,243MiB  Writes Queued:     226,242,  904,968KiB
Read Dispatches:  544,701,    2,243MiB  Write Dispatches:  159,318,  904,968KiB
Reads Requeued:         0               Writes Requeued:         0
Reads Completed:  544,716,    2,243MiB  Writes Completed:  159,321,  904,980KiB
Read Merges:       16,187,   64,748KiB  Write Merges:       61,744,  246,976KiB
IO unplugs:       149,614               Timer unplugs:       2,940

With the patch:
Reads Queued:     734,315,    2,937MiB  Writes Queued:     300,188,    1,200MiB
Read Dispatches:  214,972,    2,937MiB  Write Dispatches:  215,176,    1,200MiB
Reads Requeued:         0               Writes Requeued:         0
Reads Completed:  214,971,    2,937MiB  Writes Completed:  215,177,    1,200MiB
Read Merges:      519,343,    2,077MiB  Write Merges:       73,325,  293,300KiB
IO unplugs:       337,130               Timer unplugs:      11,184

I got ~10% to ~40% more throughput in my cases and at the same time much
lower cpu consumption when broken down per transferred kilobyte (the
majority of that due to saved interrupts and better cache handling).  In a
shared SAN others might get an additional benefit as well, because this
now causes less protocol overhead.

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tweak: deadline, cfq, row
tweaked cache pressure
fs/dcache.c: adaptive vfs_cache_pressure on suspend / resume

low vfs_cache pressure values save battery while idle, while
a low value also causes stutter with longer up times.
tweak: deadline, cfq, row
block: add runtime pm helpers

Add runtime pm helper functions:

void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
  - Initialization function for drivers to call.

int blk_pre_runtime_suspend(struct request_queue *q)
  - If any requests are in the queue, mark last busy and return -EBUSY.
    Otherwise set q->rpm_status to RPM_SUSPENDING and return 0.

void blk_post_runtime_suspend(struct request_queue *q, int err)
  - If the suspend succeeded then set q->rpm_status to RPM_SUSPENDED.
    Otherwise set it to RPM_ACTIVE and mark last busy.

void blk_pre_runtime_resume(struct request_queue *q)
  - Set q->rpm_status to RPM_RESUMING.

void blk_post_runtime_resume(struct request_queue *q, int err)
  - If the resume succeeded then set q->rpm_status to RPM_ACTIVE
    and call __blk_run_queue, then mark last busy and autosuspend.
    Otherwise set q->rpm_status to RPM_SUSPENDED.

The idea and API is designed by Alan Stern and described here:
http://marc.info/?l=linux-scsi&m=133727953625963&w=2

Change-Id: I486612af79c7887116f70a4fde552c107f7fa360
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Git-commit: 6c9546675864f51506af69eca388e5d922942c56
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>

Conflicts:
	block/blk-core.c
block: implement runtime pm strategy

When a request is added:
    If device is suspended or is suspending and the request is not a
    PM request, resume the device.

When the last request finishes:
    Call pm_runtime_mark_last_busy().

When pick a request:
    If device is resuming/suspending, then only PM request is allowed
    to go.

The idea and API is designed by Alan Stern and described here:
http://marc.info/?l=linux-scsi&m=133727953625963&w=2

Change-Id: If9c8332164afba6aeca984277e3398008ad9c45a
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Git-commit: c8158819d506a8aedeca53c52dfb709a0aabe011
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
blkpm: avoid sleep when holding queue lock

In blk_post_runtime_resume, an autosuspend request will be initiated for
the device. Since we are holding the queue lock, we can't sleep and thus
we should use the async version to initiate an autosuspend, i.e.
pm_request_suspend instead of pm_runtime_suspend, which might sleep.

Change-Id: I28cbe7e20ffdcb8f7b3329bf3b827c942dd1b45a
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Git-commit: c60855cdb976c632b3bf8922eeab8a0e78edfc04
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
block: allow REQ_PM requests even when the device is suspended

Some times even though the block device is suspended by the block layer
the low-level driver might want to queue the PM requests to the device.
Allow such requests to get peeked as the blk_pm_add_request() has already
added it to the I/O scheduler otherwise the request would be forever stuck
in the I/O scheduler without being fetched by the driver.

Change-Id: I353943a7008ea1d92ff825d220cad1828fe37c27
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
block: do not notify urgent request, when flush with data in flight

MMC device driver implements URGENT request execution with priority
(using stop flow), as a result currently running (and prepeared) request
may be reinserted back into I/O scheduler. This will break block layer
logic of flushes (flush request should not be inserted into I/O scheduler).

Block layer flush machinery keep q->flush_data_in_flight list updated with
started but not completed flush requests with data (REQ_FUA).

This change will not notify underling block device driver about pending
urgent request during flushes in flight.

Change-Id: I98113621223fe0c7d224de023db888a73bd62b48
Signed-off-by: Konstantin Dorfman <kdorfman@codeaurora.org>
cpufreq: Fix policy getting stuck when user & kernel min/max don't overlap

Every __cpufreq_set_policy starts with checking the new policy min/max has
some overlap with the current policy min/max. This works out fine until we
end up with the policy min/max being set to a range that doesn't overlap
with the user policy min/max. Once we get into this situation, the check at
the start of __cpufreq_set_policy fails and prevents us from getting out of
this state.

This only happens when one of the CPUFREQ_ADJUST/CPUFREQ_INCOMPATIBLE
notifiers called inside __cpufreq_set_policy pick a min/max outside the
range of user policy min/max.

The real intent of the check at the start of __cpufreq_set_policy is to
make sure userspace can't set user policy min > user policy max. Since
__cpufreq_set_policy always gets called only with current user policy
min/max except when the actual user space policy min/max is changed, we can
fix the issue by simply checking the new policy min/max against current
user policy min/max.

Change-Id: Iaac805825e64d7985c41fb9052bd96baacdf3d6f
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
arm: if there's no handler we need to restore sigmask, syscall or no syscall

CRs-fixed: 592079
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Git-commit: 7dfae72027cd8345247e675a3b27439df95fe06e
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-stable.git
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
arm: new way of handling ERESTART_RESTARTBLOCK

new "syscall start" flag; handled in syscall_trace() by switching
syscall number to that of syscall_restart(2).  Restarts of that
kind (ERESTART_RESTARTBLOCK) are handled by setting that bit;
syscall number is not modified until the actual call.

CRs-fixed: 592079
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Git-commit: 6b5c8045ecc7e726cdaa2a9d9c8e5008050e1252
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-stable.git
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>