locking/Documentation: Move locking related docs into Documentation/locking/

Specifically:
  Documentation/locking/lockdep-design.txt
  Documentation/locking/lockstat.txt
  Documentation/locking/mutex-design.txt
  Documentation/locking/rt-mutex-design.txt
  Documentation/locking/rt-mutex.txt
  Documentation/locking/spinlocks.txt
  Documentation/locking/ww-mutex-design.txt

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hp.com
Cc: aswin@hp.com
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Mason <clm@fb.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Josef Bacik <jbacik@fusionio.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lubomir Rintel <lkundrak@v3.sk>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: fengguang.wu@intel.com
Link: http://lkml.kernel.org/r/1406752916-3341-6-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 0 insertions, 178 deletions

diff --git a/Documentation/lockstat.txt b/Documentation/lockstat.txt
deleted file mode 100644
index 72d010689751..000000000000
--- a/Documentation/lockstat.txt
+++ /dev/null
@@ -1,178 +0,0 @@
-
-LOCK STATISTICS
-
-- WHAT
-
-As the name suggests, it provides statistics on locks.
-
-- WHY
-
-Because things like lock contention can severely impact performance.
-
-- HOW
-
-Lockdep already has hooks in the lock functions and maps lock instances to
-lock classes. We build on that (see Documentation/lockdep-design.txt).
-The graph below shows the relation between the lock functions and the various
-hooks therein.
-
-        __acquire
-            |
-           lock _____
-            |        \
-            |    __contended
-            |         |
-            |       <wait>
-            | _______/
-            |/
-            |
-       __acquired
-            |
-            .
-          <hold>
-            .
-            |
-       __release
-            |
-         unlock
-
-lock, unlock	- the regular lock functions
-__*		- the hooks
-<> 		- states
-
-With these hooks we provide the following statistics:
-
- con-bounces       - number of lock contention that involved x-cpu data
- contentions       - number of lock acquisitions that had to wait
- wait time min     - shortest (non-0) time we ever had to wait for a lock
-           max     - longest time we ever had to wait for a lock
-	   total   - total time we spend waiting on this lock
-	   avg     - average time spent waiting on this lock
- acq-bounces       - number of lock acquisitions that involved x-cpu data
- acquisitions      - number of times we took the lock
- hold time min     - shortest (non-0) time we ever held the lock
-	   max     - longest time we ever held the lock
-	   total   - total time this lock was held
-	   avg     - average time this lock was held
-
-These numbers are gathered per lock class, per read/write state (when
-applicable).
-
-It also tracks 4 contention points per class. A contention point is a call site
-that had to wait on lock acquisition.
-
- - CONFIGURATION
-
-Lock statistics are enabled via CONFIG_LOCK_STAT.
-
- - USAGE
-
-Enable collection of statistics:
-
-# echo 1 >/proc/sys/kernel/lock_stat
-
-Disable collection of statistics:
-
-# echo 0 >/proc/sys/kernel/lock_stat
-
-Look at the current lock statistics:
-
-( line numbers not part of actual output, done for clarity in the explanation
-  below )
-
-# less /proc/lock_stat
-
-01 lock_stat version 0.4
-02-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-03                              class name    con-bounces    contentions   waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg
-04-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-05
-06                         &mm->mmap_sem-W:            46             84           0.26         939.10       16371.53         194.90          47291        2922365           0.16     2220301.69 17464026916.32        5975.99
-07                         &mm->mmap_sem-R:            37            100           1.31      299502.61      325629.52        3256.30         212344       34316685           0.10        7744.91    95016910.20           2.77
-08                         ---------------
-09                           &mm->mmap_sem              1          [<ffffffff811502a7>] khugepaged_scan_mm_slot+0x57/0x280
-19                           &mm->mmap_sem             96          [<ffffffff815351c4>] __do_page_fault+0x1d4/0x510
-11                           &mm->mmap_sem             34          [<ffffffff81113d77>] vm_mmap_pgoff+0x87/0xd0
-12                           &mm->mmap_sem             17          [<ffffffff81127e71>] vm_munmap+0x41/0x80
-13                         ---------------
-14                           &mm->mmap_sem              1          [<ffffffff81046fda>] dup_mmap+0x2a/0x3f0
-15                           &mm->mmap_sem             60          [<ffffffff81129e29>] SyS_mprotect+0xe9/0x250
-16                           &mm->mmap_sem             41          [<ffffffff815351c4>] __do_page_fault+0x1d4/0x510
-17                           &mm->mmap_sem             68          [<ffffffff81113d77>] vm_mmap_pgoff+0x87/0xd0
-18
-19.............................................................................................................................................................................................................................
-20
-21                         unix_table_lock:           110            112           0.21          49.24         163.91           1.46          21094          66312           0.12         624.42       31589.81           0.48
-22                         ---------------
-23                         unix_table_lock             45          [<ffffffff8150ad8e>] unix_create1+0x16e/0x1b0
-24                         unix_table_lock             47          [<ffffffff8150b111>] unix_release_sock+0x31/0x250
-25                         unix_table_lock             15          [<ffffffff8150ca37>] unix_find_other+0x117/0x230
-26                         unix_table_lock              5          [<ffffffff8150a09f>] unix_autobind+0x11f/0x1b0
-27                         ---------------
-28                         unix_table_lock             39          [<ffffffff8150b111>] unix_release_sock+0x31/0x250
-29                         unix_table_lock             49          [<ffffffff8150ad8e>] unix_create1+0x16e/0x1b0
-30                         unix_table_lock             20          [<ffffffff8150ca37>] unix_find_other+0x117/0x230
-31                         unix_table_lock              4          [<ffffffff8150a09f>] unix_autobind+0x11f/0x1b0
-
-
-This excerpt shows the first two lock class statistics. Line 01 shows the
-output version - each time the format changes this will be updated. Line 02-04
-show the header with column descriptions. Lines 05-18 and 20-31 show the actual
-statistics. These statistics come in two parts; the actual stats separated by a
-short separator (line 08, 13) from the contention points.
-
-The first lock (05-18) is a read/write lock, and shows two lines above the
-short separator. The contention points don't match the column descriptors,
-they have two: contentions and [<IP>] symbol. The second set of contention
-points are the points we're contending with.
-
-The integer part of the time values is in us.
-
-Dealing with nested locks, subclasses may appear:
-
-32...........................................................................................................................................................................................................................
-33
-34                               &rq->lock:       13128          13128           0.43         190.53      103881.26           7.91          97454        3453404           0.00         401.11    13224683.11           3.82
-35                               ---------
-36                               &rq->lock          645          [<ffffffff8103bfc4>] task_rq_lock+0x43/0x75
-37                               &rq->lock          297          [<ffffffff8104ba65>] try_to_wake_up+0x127/0x25a
-38                               &rq->lock          360          [<ffffffff8103c4c5>] select_task_rq_fair+0x1f0/0x74a
-39                               &rq->lock          428          [<ffffffff81045f98>] scheduler_tick+0x46/0x1fb
-40                               ---------
-41                               &rq->lock           77          [<ffffffff8103bfc4>] task_rq_lock+0x43/0x75
-42                               &rq->lock          174          [<ffffffff8104ba65>] try_to_wake_up+0x127/0x25a
-43                               &rq->lock         4715          [<ffffffff8103ed4b>] double_rq_lock+0x42/0x54
-44                               &rq->lock          893          [<ffffffff81340524>] schedule+0x157/0x7b8
-45
-46...........................................................................................................................................................................................................................
-47
-48                             &rq->lock/1:        1526          11488           0.33         388.73      136294.31          11.86          21461          38404           0.00          37.93      109388.53           2.84
-49                             -----------
-50                             &rq->lock/1        11526          [<ffffffff8103ed58>] double_rq_lock+0x4f/0x54
-51                             -----------
-52                             &rq->lock/1         5645          [<ffffffff8103ed4b>] double_rq_lock+0x42/0x54
-53                             &rq->lock/1         1224          [<ffffffff81340524>] schedule+0x157/0x7b8
-54                             &rq->lock/1         4336          [<ffffffff8103ed58>] double_rq_lock+0x4f/0x54
-55                             &rq->lock/1          181          [<ffffffff8104ba65>] try_to_wake_up+0x127/0x25a
-
-Line 48 shows statistics for the second subclass (/1) of &rq->lock class
-(subclass starts from 0), since in this case, as line 50 suggests,
-double_rq_lock actually acquires a nested lock of two spinlocks.
-
-View the top contending locks:
-
-# grep : /proc/lock_stat | head
-			clockevents_lock:       2926159        2947636           0.15       46882.81  1784540466.34         605.41        3381345        3879161           0.00        2260.97    53178395.68          13.71
-		     tick_broadcast_lock:        346460         346717           0.18        2257.43    39364622.71         113.54        3642919        4242696           0.00        2263.79    49173646.60          11.59
-		  &mapping->i_mmap_mutex:        203896         203899           3.36      645530.05 31767507988.39      155800.21        3361776        8893984           0.17        2254.15    14110121.02           1.59
-			       &rq->lock:        135014         136909           0.18         606.09      842160.68           6.15        1540728       10436146           0.00         728.72    17606683.41           1.69
-	       &(&zone->lru_lock)->rlock:         93000          94934           0.16          59.18      188253.78           1.98        1199912        3809894           0.15         391.40     3559518.81           0.93
-			 tasklist_lock-W:         40667          41130           0.23        1189.42      428980.51          10.43         270278         510106           0.16         653.51     3939674.91           7.72
-			 tasklist_lock-R:         21298          21305           0.20        1310.05      215511.12          10.12         186204         241258           0.14        1162.33     1179779.23           4.89
-			      rcu_node_1:         47656          49022           0.16         635.41      193616.41           3.95         844888        1865423           0.00         764.26     1656226.96           0.89
-       &(&dentry->d_lockref.lock)->rlock:         39791          40179           0.15        1302.08       88851.96           2.21        2790851       12527025           0.10        1910.75     3379714.27           0.27
-			      rcu_node_0:         29203          30064           0.16         786.55     1555573.00          51.74          88963         244254           0.00         398.87      428872.51           1.76
-
-Clear the statistics:
-
-# echo 0 > /proc/lock_stat