msm: hotplug: Add MSM Hotplug driver
msm: hotplug: merge with latest myfluxy N5 repo
msm: hotplug: remove lcd notifier routine
msm: hotplug: set min cpus online to two
msm: kgsl: Fix policy sysfs implementation

When switching to another governor, the pwrscale kobject will be deleted
and sysfs_create_group fails due to the uninitialized kobj. This patch
deletes the kobject before attaching the file group.

[   36.270044] [<c0134304>] (__kmalloc_track_caller+0x80/0x194) from [<c010a6d0>] (kstrdup+0x2c/0x54)
[   36.270166] [<c010a6d0>] (kstrdup+0x2c/0x54) from [<c019cc98>] (create_dir+0x24/0x204)
[   36.270257] [<c019cc98>] (create_dir+0x24/0x204) from [<c019d154>] (sysfs_create_subdir+0x24/0x2c)
[   36.270318] [<c019d154>] (sysfs_create_subdir+0x24/0x2c) from [<c019e878>] (sysfs_create_group+0x40/0x1d8)
[   36.270441] [<c019e878>] (sysfs_create_group+0x40/0x1d8) from [<c0389e40>] (kgsl_pwrscale_policy_add_files+0x44/0x68)
[   36.270563] [<c0389e40>] (kgsl_pwrscale_policy_add_files+0x44/0x68) from [<c038e714>] (conservative_init+0xc/0x18)
[   36.270654] [<c038e714>] (conservative_init+0xc/0x18) from [<c0389c6c>] (pwrscale_policy_store+0xcc/0x154)
[   36.270776] [<c0389c6c>] (pwrscale_policy_store+0xcc/0x154) from [<c0389a90>] (pwrscale_sysfs_store+0x20/0x2c)
[   36.270868] [<c0389a90>] (pwrscale_sysfs_store+0x20/0x2c) from [<c019b2a4>] (sysfs_write_file+0x168/0x198)
[   36.270990] [<c019b2a4>] (sysfs_write_file+0x168/0x198) from [<c01382c4>] (vfs_write+0x9c/0x170)
[   36.271112] [<c01382c4>] (vfs_write+0x9c/0x170) from [<c0138440>] (sys_write+0x38/0x70)
[   36.271173] [<c0138440>] (sys_write+0x38/0x70) from [<c000f000>] (ret_fast_syscall+0x0/0x30)
[   36.271265] Code: e7925001 e3550000 0a000033 e5942014 (e795a002)
[   36.271661] ---[ end trace ef0d8b9c8acc7bbb ]---
msm: kgsl: Import conservative governor from jb422 branch

Conflicts:
	drivers/gpu/msm/kgsl_pwrscale.c
msm: kgsl: conservative: Update thresholds

The idea is to keep it from dropping to level 3 too early while
scolling.
msm: kgsl: conservative: change perms to 664
prima: core: change path for WCNSS_qcom_cfg.ini
makefile: remove Wno-sizeof-pointer-memaccess
ARM: makefile: remove march=armv7-a for satisfy targeting MSM Krait CPUs
Perf: add the correct path for perf_trace_counters
time: RCU permitted to stop idle entry via softirq

From: "Paul E. McKenney" <paul.mckenney@xxxxxxxxxx>

The can_stop_idle_tick() function complains if a softirq vector is
raised too late in the idle-entry process, presumably in order to
prevent dangling softirq invocations from being delayed across the
full idle period, which might be indefinitely long -- and if softirq
was asserted any later than the call to this function, such a delay
might well happen.

However, RCU needs to be able to use softirq to stop idle entry in
order to be able to drain RCU callbacks from the current CPU, which in
turn enables faster entry into dyntick-idle mode, which in turn reduces
power consumption. Because RCU takes this action at a well-defined
point in the idle-entry path, it is safe for RCU to take this approach.

This commit therefore silences the error message that is sometimes
produced when the going-idle CPU suddenly finds that it has an RCU_SOFTIRQ
to process. The error message will continue to be issued for other
softirq vectors.

Reported-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
Signed-off-by: Paul E. McKenney <paul.mckenney@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
sched: Add sysinterface for GENTLE_FAIR_SLEEPERS

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched: GENTLE_FAIR_SLEEPERS fix unused cpu var
codel: Controlled Delay AQM

An implementation of CoDel AQM, from Kathleen Nichols and Van Jacobson.

http://queue.acm.org/detail.cfm?id=2209336

This AQM main input is no longer queue size in bytes or packets, but the
delay packets stay in (FIFO) queue.

As we don't have infinite memory, we still can drop packets in enqueue()
in case of massive load, but mean of CoDel is to drop packets in
dequeue(), using a control law based on two simple parameters :

target : target sojourn time (default 5ms)
interval : width of moving time window (default 100ms)

Based on initial work from Dave Taht.

Refactored to help future codel inclusion as a plugin for other linux
qdisc (FQ_CODEL, ...), like RED.

include/net/codel.h contains codel algorithm as close as possible than
Kathleen reference.

net/sched/sch_codel.c contains the linux qdisc specific glue.

Separate structures permit a memory efficient implementation of fq_codel
(to be sent as a separate work) : Each flow has its own struct
codel_vars.

timestamps are taken at enqueue() time with 1024 ns precision, allowing
a range of 2199 seconds in queue, and 100Gb links support. iproute2 uses
usec as base unit.

Selected packets are dropped, unless ECN is enabled and packets can get
ECN mark instead.

Tested from 2Mb to 10Gb speeds with no particular problems, on ixgbe and
tg3 drivers (BQL enabled).

Usage: tc qdisc ... codel [ limit PACKETS ] [ target TIME ]
                          [ interval TIME ] [ ecn ]

qdisc codel 10: parent 1:1 limit 2000p target 3.0ms interval 60.0ms ecn
 Sent 13347099587 bytes 8815805 pkt (dropped 0, overlimits 0 requeues 0)
 rate 202365Kbit 16708pps backlog 113550b 75p requeues 0
  count 116 lastcount 98 ldelay 4.3ms dropping drop_next 816us
  maxpacket 1514 ecn_mark 84399 drop_overlimit 0

CoDel must be seen as a base module, and should be used keeping in mind
there is still a FIFO queue. So a typical setup will probably need a
hierarchy of several qdiscs and packet classifiers to be able to meet
whatever constraints a user might have.

One possible example would be to use fq_codel, which combines Fair
Queueing and CoDel, in replacement of sfq / sfq_red.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Dave Taht <dave.taht@bufferbloat.net>
Cc: Kathleen Nichols <nichols@pollere.com>
Cc: Van Jacobson <van@pollere.net>
Cc: Tom Herbert <therbert@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fq_codel: Fair Queue Codel AQM

Fair Queue Codel packet scheduler

Principles :

- Packets are classified (internal classifier or external) on flows.
- This is a Stochastic model (as we use a hash, several flows might
                              be hashed on same slot)
- Each flow has a CoDel managed queue.
- Flows are linked onto two (Round Robin) lists,
  so that new flows have priority on old ones.

- For a given flow, packets are not reordered (CoDel uses a FIFO)
- head drops only.
- ECN capability is on by default.
- Very low memory footprint (64 bytes per flow)

tc qdisc ... fq_codel [ limit PACKETS ] [ flows number ]
                      [ target TIME ] [ interval TIME ] [ noecn ]
                      [ quantum BYTES ]

defaults : 1024 flows, 10240 packets limit, quantum : device MTU
           target : 5ms (CoDel default)
           interval : 100ms (CoDel default)

Impressive results on load :

class htb 1:1 root leaf 10: prio 0 quantum 1514 rate 200000Kbit ceil 200000Kbit burst 1475b/8 mpu 0b overhead 0b cburst 1475b/8 mpu 0b overhead 0b level 0
 Sent 43304920109 bytes 33063109 pkt (dropped 0, overlimits 0 requeues 0)
 rate 201691Kbit 28595pps backlog 0b 312p requeues 0
 lended: 33063109 borrowed: 0 giants: 0
 tokens: -912 ctokens: -912

class fq_codel 10:1735 parent 10:
 (dropped 1292, overlimits 0 requeues 0)
 backlog 15140b 10p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:4524 parent 10:
 (dropped 1291, overlimits 0 requeues 0)
 backlog 16654b 11p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:4e74 parent 10:
 (dropped 1290, overlimits 0 requeues 0)
 backlog 6056b 4p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 6.4ms dropping drop_next 92.0ms
class fq_codel 10:628a parent 10:
 (dropped 1289, overlimits 0 requeues 0)
 backlog 7570b 5p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 5.4ms dropping drop_next 90.9ms
class fq_codel 10:a4b3 parent 10:
 (dropped 302, overlimits 0 requeues 0)
 backlog 16654b 11p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:c3c2 parent 10:
 (dropped 1284, overlimits 0 requeues 0)
 backlog 13626b 9p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 5.9ms
class fq_codel 10:d331 parent 10:
 (dropped 299, overlimits 0 requeues 0)
 backlog 15140b 10p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 7.0ms
class fq_codel 10:d526 parent 10:
 (dropped 12160, overlimits 0 requeues 0)
 backlog 35870b 211p requeues 0
  deficit 1508 count 12160 lastcount 1 ldelay 15.3ms dropping drop_next 247us
class fq_codel 10:e2c6 parent 10:
 (dropped 1288, overlimits 0 requeues 0)
 backlog 15140b 10p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
class fq_codel 10:eab5 parent 10:
 (dropped 1285, overlimits 0 requeues 0)
 backlog 16654b 11p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 5.9ms
class fq_codel 10:f220 parent 10:
 (dropped 1289, overlimits 0 requeues 0)
 backlog 15140b 10p requeues 0
  deficit 1514 count 1 lastcount 1 ldelay 7.1ms

qdisc htb 1: root refcnt 6 r2q 10 default 1 direct_packets_stat 0 ver 3.17
 Sent 43331086547 bytes 33092812 pkt (dropped 0, overlimits 66063544 requeues 71)
 rate 201697Kbit 28602pps backlog 0b 260p requeues 71
qdisc fq_codel 10: parent 1:1 limit 10240p flows 65536 target 5.0ms interval 100.0ms ecn
 Sent 43331086547 bytes 33092812 pkt (dropped 949359, overlimits 0 requeues 0)
 rate 201697Kbit 28602pps backlog 189352b 260p requeues 0
  maxpacket 1514 drop_overlimit 0 new_flow_count 5582 ecn_mark 125593
  new_flows_len 0 old_flows_len 11

PING 172.30.42.18 (172.30.42.18) 56(84) bytes of data.
64 bytes from 172.30.42.18: icmp_req=1 ttl=64 time=0.227 ms
64 bytes from 172.30.42.18: icmp_req=2 ttl=64 time=0.165 ms
64 bytes from 172.30.42.18: icmp_req=3 ttl=64 time=0.166 ms
64 bytes from 172.30.42.18: icmp_req=4 ttl=64 time=0.151 ms
64 bytes from 172.30.42.18: icmp_req=5 ttl=64 time=0.164 ms
64 bytes from 172.30.42.18: icmp_req=6 ttl=64 time=0.172 ms
64 bytes from 172.30.42.18: icmp_req=7 ttl=64 time=0.175 ms
64 bytes from 172.30.42.18: icmp_req=8 ttl=64 time=0.183 ms
64 bytes from 172.30.42.18: icmp_req=9 ttl=64 time=0.158 ms
64 bytes from 172.30.42.18: icmp_req=10 ttl=64 time=0.200 ms

10 packets transmitted, 10 received, 0% packet loss, time 8999ms
rtt min/avg/max/mdev = 0.151/0.176/0.227/0.022 ms

Much better than SFQ because of priority given to new flows, and fast
path dirtying less cache lines.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
codel: use Newton method instead of sqrt() and divides

As Van pointed out, interval/sqrt(count) can be implemented using
multiplies only.

http://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Iterative_methods_for_reciprocal_square_roots

This patch implements the Newton method and reciprocal divide.

Total cost is 15 cycles instead of 120 on my Corei5 machine (64bit
kernel).

There is a small 'error' for count values < 5, but we don't really care.

I reuse a hole in struct codel_vars :
 - pack the dropping boolean into one bit
 - use 31bit to store the reciprocal value of sqrt(count).

Suggested-by: Van Jacobson <van@pollere.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Dave Taht <dave.taht@bufferbloat.net>
Cc: Kathleen Nichols <nichols@pollere.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/codel: Add missing #include <linux/prefetch.h>

m68k allmodconfig:

net/sched/sch_codel.c: In function ‘dequeue’:
net/sched/sch_codel.c:70: error: implicit declaration of function ‘prefetch’
make[1]: *** [net/sched/sch_codel.o] Error 1

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
codel: use u16 field instead of 31bits for rec_inv_sqrt

David pointed out gcc might generate poor code with 31bit fields.

Using u16 is more than enough and permits a better code output.

Also make the code intent more readable using constants, fixed point arithmetic
not being trivial for everybody.

Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>