rcu: Yield simpler

The rcu_yield() code is amazing. It's there to avoid starvation of the
system when lots of (boosting) work is to be done.

Now looking at the code it's functionality is:

 Make the thread SCHED_OTHER and very nice, i.e. get it out of the way
 Arm a timer with 2 ticks
 schedule()

Now if the system goes idle the rcu task returns, regains SCHED_FIFO
and plugs on. If the systems stays busy the timer fires and wakes a
per node kthread which in turn makes the per cpu thread SCHED_FIFO and
brings it back on the cpu. For the boosting thread the "make it FIFO"
bit is missing and it just runs some magic boost checks. Now this is a
lot of code with extra threads and complexity.

It's way simpler to let the tasks when they detect overload schedule
away for 2 ticks and defer the normal wakeup as long as they are in
yielded state and the cpu is not idle.

That solves the same problem and the only difference is that when the
cpu goes idle it's not guaranteed that the thread returns right away,
but it won't be longer out than two ticks, so no harm is done. If
that's an issue than it is way simpler just to wake the task from
idle as RCU has callbacks there anyway.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120716103948.131256723@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
rcu: Use smp_hotplug_thread facility for RCUs per-CPU kthread

Bring RCU into the new-age CPU-hotplug fold by modifying RCU's per-CPU
kthread code to use the new smp_hotplug_thread facility.

[ tglx: Adapted it to use callbacks and to the simplified rcu yield ]

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20120716103948.673354828@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
msm: msm_bus: Don't divide RPM BW requests

When sending bandwidth requests to slave don't divide the request by
the number of ports as this is done at the RPM driver.

CRs-Fixed: 611965
Change-Id: Ie6870b66d1621677d94e4441136aed89bbdb6595
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>
msm: kgsl: Pass the right timeout to adreno_drawctxt_wait()

adreno_drawctxt_wait() expects the passed in timeout to be in
milliseconds and converts it to jiffies.  Unfortunately, so does
the caller so the timeout is shorter than it should be.

Change-Id: Ic0dedbad85d50b32dba0fbf3ebb914335bf55166
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
msm: kgsl: Fix the api type in adreno drawctxt flags

Adding the missed type field in adreno draw ctxt create
which was giving incorrect data type.

CRs-Fixed: 590103

Signed-off-by: Anoop Kumar Yerukala <ayeruk@codeaurora.org>
Signed-off-by: Prabhat Awasthi <pawasthi@codeaurora.org>
Change-Id: I6f464a3b6cc1fec3891d1189f85c7fe9ac65764e
msm: kgsl: protect syncpoint events with a reference count

Replace the event spinlock with krefs to avoid the possiblity
of calling a sleeping function while holding the spinlock and
to generally make the whole cmdbatch cancel loop a lot more
stable.

Change-Id: I08ba54fa4c5a11c05e3503dfc6a4ee040733e5a6
Signed-off-by: Jeff Boody <jboody@codeaurora.org>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
msm: kgsl: The memory entry pending flag should be guarded

Guard the memory entry free pending flag with the process
private lock. This usage of this flag is guarded everywhere
else in the code with the same lock.

Change-Id: Iac27f08876bfe8ff6205edc8233b9c27c6e9a599
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>
msm: kgsl: Changing to kref_get_unless_zero for process refcount

Do not allow anything to get a refcount to the process_private
structure if its refcount has gone down to 0.

Change-Id: I7cd6f731286aebfc84c288284599b47f666dcd47
Signed-off-by: Shrenuj Bansal <shrenujb@codeaurora.org>
msm: kgsl: Wake gpu up on the max freq when using the performance governor

Use the flag provided by the performance governor on the device
suspend/slumber to wake it up later on the max gpu frequency.

Change-Id: Ia8284458ffe9cd17eb8e87b2eb84c485ae6e8afa
Signed-off-by: Vladimir Razgulin <vrazguli@codeaurora.org>
msm: kgsl: Use GPU to switch pagetables when current one is default

Use the GPU to switch pagetables even if the current pagetable is
the default pagetable. This requires that commands are submitted to
GPU that do not belong to any context since the current context is
a NULL one. This is better for performance because if GPU is not
used to switch pagetable then synchronization is required between the
GPU and CPU.

Change-Id: I6c1a161fed0747714a86419cdd873ac080466bbf
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>
msm: sps: Add integer wrap check for debugfs buffer

When converting debugfs buffer size to kilobytes value
there is a possible integer overflow and it may result
into negative value.

Fix the issue by adding integer wrap check for buffer
size just before conversion.

CRs-fixed: 564177
Change-Id: If4615561ea6a1c58e8be8c1b72f7881c068d8520
Signed-off-by: Dipen Parmar <dipenp@codeaurora.org>
mm: fix calculation of dirtyable memory

The system uses global_dirtyable_memory() to calculate number of
dirtyable pages/pages that can be allocated to the page cache.  A bug
causes an underflow thus making the page count look like a big unsigned
number.  This in turn confuses the dirty writeback throttling to
aggressively write back pages as they become dirty (usually 1 page at a
time).  This generally only affects systems with highmem because the
underflowed count gets subtracted from the global count of dirtyable
memory.

The problem was introduced with v3.2-4896-gab8fabd

Fix is to ensure we don't get an underflowed total of either highmem or
global dirtyable memory.

Change-Id: Ib0c4a8f99870edc5ded863b88a472f2836c690d2
Signed-off-by: Sonny Rao <sonnyrao@chromium.org>
Signed-off-by: Puneet Kumar <puneetster@chromium.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Damien Wyart <damien.wyart@free.fr>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: c8b74c2f6604923de91f8aa6539f8bb934736754
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
netfilter: x_tables: fix ordering of jumpstack allocation and table update

During kernel stability testing on an SMP ARMv7 system, Yalin Wang
reported the following panic from the netfilter code:

  1fe0: 0000001c 5e2d3b10 4007e779 4009e110 60000010 00000032 ff565656 ff545454
  [<c06c48dc>] (ipt_do_table+0x448/0x584) from [<c0655ef0>] (nf_iterate+0x48/0x7c)
  [<c0655ef0>] (nf_iterate+0x48/0x7c) from [<c0655f7c>] (nf_hook_slow+0x58/0x104)
  [<c0655f7c>] (nf_hook_slow+0x58/0x104) from [<c0683bbc>] (ip_local_deliver+0x88/0xa8)
  [<c0683bbc>] (ip_local_deliver+0x88/0xa8) from [<c0683718>] (ip_rcv_finish+0x418/0x43c)
  [<c0683718>] (ip_rcv_finish+0x418/0x43c) from [<c062b1c4>] (__netif_receive_skb+0x4cc/0x598)
  [<c062b1c4>] (__netif_receive_skb+0x4cc/0x598) from [<c062b314>] (process_backlog+0x84/0x158)
  [<c062b314>] (process_backlog+0x84/0x158) from [<c062de84>] (net_rx_action+0x70/0x1dc)
  [<c062de84>] (net_rx_action+0x70/0x1dc) from [<c0088230>] (__do_softirq+0x11c/0x27c)
  [<c0088230>] (__do_softirq+0x11c/0x27c) from [<c008857c>] (do_softirq+0x44/0x50)
  [<c008857c>] (do_softirq+0x44/0x50) from [<c0088614>] (local_bh_enable_ip+0x8c/0xd0)
  [<c0088614>] (local_bh_enable_ip+0x8c/0xd0) from [<c06b0330>] (inet_stream_connect+0x164/0x298)
  [<c06b0330>] (inet_stream_connect+0x164/0x298) from [<c061d68c>] (sys_connect+0x88/0xc8)
  [<c061d68c>] (sys_connect+0x88/0xc8) from [<c000e340>] (ret_fast_syscall+0x0/0x30)
  Code: 2a000021 e59d2028 e59de01c e59f011c (e7824103)
  ---[ end trace da227214a82491bd ]---
  Kernel panic - not syncing: Fatal exception in interrupt

This comes about because CPU1 is executing xt_replace_table in response
to a setsockopt syscall, resulting in:

	ret = xt_jumpstack_alloc(newinfo);
		--> newinfo->jumpstack = kzalloc(size, GFP_KERNEL);

	[...]

	table->private = newinfo;
	newinfo->initial_entries = private->initial_entries;

Meanwhile, CPU0 is handling the network receive path and ends up in
ipt_do_table, resulting in:

	private = table->private;

	[...]

	jumpstack  = (struct ipt_entry **)private->jumpstack[cpu];

On weakly ordered memory architectures, the writes to table->private
and newinfo->jumpstack from CPU1 can be observed out of order by CPU0.
Furthermore, on architectures which don't respect ordering of address
dependencies (i.e. Alpha), the reads from CPU0 can also be re-ordered.

This patch adds an smp_wmb() before the assignment to table->private
(which is essentially publishing newinfo) to ensure that all writes to
newinfo will be observed before plugging it into the table structure.
A dependent-read barrier is also added on the consumer sides, to ensure
the same ordering requirements are also respected there.

Change-Id: Ia320d52510d7184c0f13d7f130102dbe685e8d6f
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reported-by: Wang, Yalin <Yalin.Wang@sonymobile.com>
Tested-by: Wang, Yalin <Yalin.Wang@sonymobile.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Git-commit: b416c144f46af1a30ddfa4e4319a8f077381ad63
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>
net: sock: validate data_len before allocating skb in sock_alloc_send_pskb()

We need to validate the number of pages consumed by data_len, otherwise frags
array could be overflowed by userspace. So this patch validate data_len and
return -EMSGSIZE when data_len may occupies more frags than MAX_SKB_FRAGS.

Change-Id: I2a7d6bb93e4fa04efc6f576d22277f43b11257d3
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: cc9b17ad29ecaa20bfe426a8d4dbfb94b13ff1cc
Git-repo: https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
crypto: msm: multiple qce50 support

In some platforms such as fsm9900, multiple instances of qce50 hw
may be supported.  Each qce50 HW has an ndp-bam. Each qce50 HW
can support multiple instances of qce_dev platform device.
Each qce_dev has its own configured pipe set and associated qce50 HW,
defined by crypto-base and bam-pipe-pair fields in the device tree files.
This patch based on io address, it decides to create a new qce50 hw
instance or use the existing known instance at device probe time.

Furthermore, this patch does iomap for only once for each HW BAM instance
to avoid issue with bam driver. If modprobe, and rmmod of qcedev,
and qcrypto are not in first in last out order, kernel may crash in
bam driver in the last rmmod.
This saves virtual space for IO if multiple instances of qcedev
share the same instance of HW BAM.

Change-Id: I1565b1976981b0512832ff793e0adb29c4be3ccc
Acked-by: Chemin Hsieh <cheminh@qti.qualcomm.com>
Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Signed-off-by: Zhen Kong <zkong@codeaurora.org>
crypto: Fix memory leak in bam_release call

Release pmab memory when an error occurs as well.

Change-Id: I7aa13d5a03edbdfa806345039459feaeac6e7a11
Signed-off-by: Mona Hossain <mhossain@codeaurora.org>
Signed-off-by: Zhen Kong <zkong@codeaurora.org>
crypto: msm: Fix issues related to non-zero byteoffset input

Fix buffer overflow for a non-zero byteoffset value.

Also fixes memory leak issue by adding data_len check in check_params.
One of the scenarios data_len can be less than byteoffset which results
in memory leak with huge data length, which might cause the kernel panic.

Change-Id: I3f773673219f45dad4f17499b1ee0feda2aff1f7
Signed-off-by: AnilKumar Chimata <anilc@codeaurora.org>
crypto: msm: Remove invalid check in qcedev driver

Unsigned int variable is compared for < 0, which is an invalid if
condition. This patch removes the check.

Change-Id: I76c10223672db2c387e025697dd8bd921e5ddc1b
Signed-off-by: AnilKumar Chimata <anilc@codeaurora.org>
crypto: msm: qce50 ota crypto support

Kasumi/snow-3g f8/f9 are defined by 3gpp, as the algorithms for
UMTS, and LTE for over the air ciphering and integrity. The
algorithms are supported by crypto 5 hardware. This patch
enables qce50 driver to provide Kasumi/snow-3g f8/f9
ciphering and integrity services.

Acked-by: hemin Hsieh <cheminh@qti.qualcomm.com>
Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Signed-off-by: Zhen Kong <zkong@codeaurora.org>
crypto: msm: Handle error case

Release memory and disable clk when sps_init fails.

Signed-off-by: Mona Hossain <mhossain@codeaurora.org>
Signed-off-by: Zhen Kong <zkong@codeaurora.org>