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[PATCH 1/3] locking/percpu-rwsem: Move text file into Documentation/locking/

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Although this is rather useless and the actual code is orders
of magnitude more detailed and informative than this document.

Might as well keep it instead, I guess its already there and
could give a user a quick why/when use them vs regular rwsems.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 Documentation/locking/percpu-rw-semaphore.txt | 27 +++++++++++++++++++++++++++
 Documentation/percpu-rw-semaphore.txt         | 27 ---------------------------
 2 files changed, 27 insertions(+), 27 deletions(-)
 create mode 100644 Documentation/locking/percpu-rw-semaphore.txt
 delete mode 100644 Documentation/percpu-rw-semaphore.txt

diff --git a/Documentation/locking/percpu-rw-semaphore.txt b/Documentation/locking/percpu-rw-semaphore.txt
new file mode 100644
index 000000000000..7d3c82431909
--- /dev/null
+++ b/Documentation/locking/percpu-rw-semaphore.txt
@@ -0,0 +1,27 @@
+Percpu rw semaphores
+--------------------
+
+Percpu rw semaphores is a new read-write semaphore design that is
+optimized for locking for reading.
+
+The problem with traditional read-write semaphores is that when multiple
+cores take the lock for reading, the cache line containing the semaphore
+is bouncing between L1 caches of the cores, causing performance
+degradation.
+
+Locking for reading is very fast, it uses RCU and it avoids any atomic
+instruction in the lock and unlock path. On the other hand, locking for
+writing is very expensive, it calls synchronize_rcu() that can take
+hundreds of milliseconds.
+
+The lock is declared with "struct percpu_rw_semaphore" type.
+The lock is initialized percpu_init_rwsem, it returns 0 on success and
+-ENOMEM on allocation failure.
+The lock must be freed with percpu_free_rwsem to avoid memory leak.
+
+The lock is locked for read with percpu_down_read, percpu_up_read and
+for write with percpu_down_write, percpu_up_write.
+
+The idea of using RCU for optimized rw-lock was introduced by
+Eric Dumazet <eric.dumazet@gmail.com>.
+The code was written by Mikulas Patocka <mpatocka@redhat.com>
diff --git a/Documentation/percpu-rw-semaphore.txt b/Documentation/percpu-rw-semaphore.txt
deleted file mode 100644
index 7d3c82431909..000000000000
--- a/Documentation/percpu-rw-semaphore.txt
+++ /dev/null
@@ -1,27 +0,0 @@
-Percpu rw semaphores
---------------------
-
-Percpu rw semaphores is a new read-write semaphore design that is
-optimized for locking for reading.
-
-The problem with traditional read-write semaphores is that when multiple
-cores take the lock for reading, the cache line containing the semaphore
-is bouncing between L1 caches of the cores, causing performance
-degradation.
-
-Locking for reading is very fast, it uses RCU and it avoids any atomic
-instruction in the lock and unlock path. On the other hand, locking for
-writing is very expensive, it calls synchronize_rcu() that can take
-hundreds of milliseconds.
-
-The lock is declared with "struct percpu_rw_semaphore" type.
-The lock is initialized percpu_init_rwsem, it returns 0 on success and
--ENOMEM on allocation failure.
-The lock must be freed with percpu_free_rwsem to avoid memory leak.
-
-The lock is locked for read with percpu_down_read, percpu_up_read and
-for write with percpu_down_write, percpu_up_write.
-
-The idea of using RCU for optimized rw-lock was introduced by
-Eric Dumazet <eric.dumazet@gmail.com>.
-The code was written by Mikulas Patocka <mpatocka@redhat.com>
-- 
2.6.6

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[PATCH -tip 0/3] locking/percpu-rwsem: writer-side optimizations Davidlohr Bueso <dave@stgolabs.net> - 2016-11-18 20:00 +0100
  [PATCH 1/3] locking/percpu-rwsem: Move text file into Documentation/locking/ Davidlohr Bueso <dave@stgolabs.net> - 2016-11-18 20:00 +0100
  [PATCH 2/3] locking/percpu-rwsem: Replace bulky wait-queues with swait Davidlohr Bueso <dave@stgolabs.net> - 2016-11-18 20:00 +0100
    Re: [PATCH 2/3] locking/percpu-rwsem: Replace bulky wait-queues         with swait Oleg Nesterov <oleg@redhat.com> - 2016-11-21 14:00 +0100
      Re: [PATCH 2/3] locking/percpu-rwsem: Replace bulky wait-queues with  swait Davidlohr Bueso <dave@stgolabs.net> - 2016-11-21 18:30 +0100
  [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer wakeups Davidlohr Bueso <dave@stgolabs.net> - 2016-11-18 20:00 +0100
    Re: [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer  wakeups Peter Zijlstra <peterz@infradead.org> - 2016-11-21 13:30 +0100
      Re: [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer         wakeups Oleg Nesterov <oleg@redhat.com> - 2016-11-21 13:50 +0100
        Re: [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer         wakeups Oleg Nesterov <oleg@redhat.com> - 2016-11-21 16:10 +0100
          Re: [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer  wakeups Davidlohr Bueso <dave@stgolabs.net> - 2016-11-22 05:00 +0100
            Re: [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer         wakeups Oleg Nesterov <oleg@redhat.com> - 2016-11-23 15:50 +0100
    Re: [PATCH 3/3] locking/percpu-rwsem: Avoid unnecessary writer         wakeups Oleg Nesterov <oleg@redhat.com> - 2016-11-21 13:30 +0100

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