block,elevator: use new hashtable implementation

Switch elevator to use the new hashtable implementation. This reduces the
amount of generic unrelated code in the elevator.

This also removes the dymanic allocation of the hash table. The size of the table is
constant so there's no point in paying the price of an extra dereference when accessing
it.

This patch depends on d9b482c ("hashtable: introduce a small and naive
hashtable") which was merged in v3.6.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
mm/ksm.c: use new hashtable implementation

Switch ksm to use the new hashtable implementation.  This reduces the
amount of generic unrelated code in the ksm module.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
rwsem-optimizations [read more]

Merge rwsem optimizations from Michel Lespinasse:
 "These patches extend Alex Shi's work (which added write lock stealing
  on the rwsem slow path) in order to provide rwsem write lock stealing
  on the fast path (that is, without taking the rwsem's wait_lock).

  I have unfortunately been unable to push this through -next before due
  to Ingo Molnar / David Howells / Peter Zijlstra being busy with other
  things.  However, this has gotten some attention from Rik van Riel and
  Davidlohr Bueso who both commented that they felt this was ready for
  v3.10, and Ingo Molnar has said that he was OK with me pushing
  directly to you.  So, here goes :)

  Davidlohr got the following test results from pgbench running on a
  quad-core laptop:

    | db_size | clients  |  tps-vanilla   |   tps-rwsem  |
    +---------+----------+----------------+--------------+
    | 160 MB   |       1 |           5803 |         6906 | + 19.0%
    | 160 MB   |       2 |          13092 |        15931 |
    | 160 MB   |       4 |          29412 |        33021 |
    | 160 MB   |       8 |          32448 |        34626 |
    | 160 MB   |      16 |          32758 |        33098 |
    | 160 MB   |      20 |          26940 |        31343 | + 16.3%
    | 160 MB   |      30 |          25147 |        28961 |
    | 160 MB   |      40 |          25484 |        26902 |
    | 160 MB   |      50 |          24528 |        25760 |
    ------------------------------------------------------
    | 1.6 GB   |       1 |           5733 |         7729 | + 34.8%
    | 1.6 GB   |       2 |           9411 |        19009 | + 101.9%
    | 1.6 GB   |       4 |          31818 |        33185 |
    | 1.6 GB   |       8 |          33700 |        34550 |
    | 1.6 GB   |      16 |          32751 |        33079 |
    | 1.6 GB   |      20 |          30919 |        31494 |
    | 1.6 GB   |      30 |          28540 |        28535 |
    | 1.6 GB   |      40 |          26380 |        27054 |
    | 1.6 GB   |      50 |          25241 |        25591 |
    ------------------------------------------------------
    | 7.6 GB   |       1 |           5779 |         6224 |
    | 7.6 GB   |       2 |          10897 |        13611 | + 24.9%
    | 7.6 GB   |       4 |          32683 |        33108 |
    | 7.6 GB   |       8 |          33968 |        34712 |
    | 7.6 GB   |      16 |          32287 |        32895 |
    | 7.6 GB   |      20 |          27770 |        31689 | + 14.1%
    | 7.6 GB   |      30 |          26739 |        29003 |
    | 7.6 GB   |      40 |          24901 |        26683 |
    | 7.6 GB   |      50 |          17115 |        25925 | + 51.5%
    ------------------------------------------------------

  (Davidlohr also has one additional patch which further improves
  throughput, though I will ask him to send it directly to you as I have
  suggested some minor changes)."

* emailed patches from Michel Lespinasse <walken@google.com>:
  rwsem: no need for explicit signed longs
  x86 rwsem: avoid taking slow path when stealing write lock
  rwsem: do not block readers at head of queue if other readers are active
  rwsem: implement support for write lock stealing on the fastpath
  rwsem: simplify __rwsem_do_wake
  rwsem: skip initial trylock in rwsem_down_write_failed
  rwsem: avoid taking wait_lock in rwsem_down_write_failed
  rwsem: use cmpxchg for trying to steal write lock
  rwsem: more agressive lock stealing in rwsem_down_write_failed
  rwsem: simplify rwsem_down_write_failed
  rwsem: simplify rwsem_down_read_failed
  rwsem: move rwsem_down_failed_common code into rwsem_down_{read,write}_failed
  rwsem: shorter spinlocked section in rwsem_down_failed_common()
  rwsem: make the waiter type an enumeration rather than a bitmask

Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>

Conflicts:
	lib/rwsem.c
asm-generic: rwsem: ensure sem->cnt is only accessed via atomic_long_*

The asm-generic rwsem implementation directly acceses sem->cnt when
performing a __down_read_trylock operation. Whilst this is probably safe
on all architectures, we should stick to the atomic_long_* API and use
atomic_long_read instead.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
asm-generic: rwsem: de-PPCify rwsem.h

asm-generic/rwsem.h used to live under arch/powerpc. During its
liberation to common code, a few references to its former home where
preserved, in particular the definition of RWSEM_ACTIVE_MASK is
predicated on CONFIG_PPC64.

This patch updates the ifdefs and comments to architecturally neutral
versions.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
msm: bam_dmux: fix compilation issue

Change-Id: Ie4dd92ce622a1e59bd415b0d8ba25c1896b20fab
Signed-off-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>
[ljc: also call BUG instead of panic]
Signed-off-by: Luis Cruz <ljc2491@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>

Signed-off-by: Lens-F <tnoah12@gmail.com>
DRIVERS: SLIMBUS: some more tweaks:
Set ROOT_FREQ at 22, which is double what we had before. According to some documents this is what we want for optimium audio quality
Forcec SLIM_RATE to 44.1KHz and 48KHz instead of much lower values. This way it will be forced to run at these freqs to match the majority of audio files user will be playing.

ZeroInfinity/Poondog

Signed-off-by: ZeroInfinity <infinitezero345@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
af_unix: speedup /proc/net/unix

/proc/net/unix has quadratic behavior, and can hold unix_table_lock for
a while if high number of unix sockets are alive. (90 ms for 200k
sockets...)

We already have a hash table, so its quite easy to use it.

Problem is unbound sockets are still hashed in a single hash slot
(unix_socket_table[UNIX_HASH_TABLE])

This patch also spreads unbound sockets to 256 hash slots, to speedup
both /proc/net/unix and unix_diag.

Time to read /proc/net/unix with 200k unix sockets :
(time dd if=/proc/net/unix of=/dev/null bs=4k)

before : 520 secs
after : 2 secs

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>
tcp: move duplicate code from tcp_v4_init_sock()/tcp_v6_init_sock()

This commit moves the (substantial) common code shared between
tcp_v4_init_sock() and tcp_v6_init_sock() to a new address-family
independent function, tcp_init_sock().

Centralizing this functionality should help avoid drift issues,
e.g. where the IPv4 side is updated without a corresponding update to
IPv6. There was already some drift: IPv4 initialized snd_cwnd to
TCP_INIT_CWND, while the IPv6 side was still initializing snd_cwnd to
2 (in this case it should not matter, since snd_cwnd is also
initialized in tcp_init_metrics(), but the general risks and
maintenance overhead remain).

When diffing the old and new code, note that new tcp_init_sock()
function uses the order of steps from the tcp_v4_init_sock()
implementation (the order is slightly different in
tcp_v6_init_sock()).

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: poondog <markj338@gmail.com>
Signed-off-by: Lens-F <tnoah12@gmail.com>