Commit:     34aebfd3bdc93c0c5614f1f61e43b6ddc4be52ae
Parent:     545c4423335469de06af7f7c95e97c1122c1c818
Author:     Li Zefan <[EMAIL PROTECTED]>
AuthorDate: Thu Jan 17 15:21:20 2008 -0800
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Thu Jan 17 15:38:59 2008 -0800

    Revert "local_t Documentation update"
    This reverts commit e1265205c0ee3919c3f2c750662630154c8faab2.
    It's a duplicate commit of commit 74beb9db77930be476b267ec8518a642f39a04bf,
    resulting in a duplicate section.
    Signed-off-by: Li Zefan <[EMAIL PROTECTED]>
    Acked-by: Mathieu Desnoyers <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
 Documentation/local_ops.txt |   23 -----------------------
 1 files changed, 0 insertions(+), 23 deletions(-)

diff --git a/Documentation/local_ops.txt b/Documentation/local_ops.txt
index 1a45f11..4269a11 100644
--- a/Documentation/local_ops.txt
+++ b/Documentation/local_ops.txt
@@ -68,29 +68,6 @@ typedef struct { atomic_long_t a; } local_t;
   variable can be read when reading some _other_ cpu's variables.
-* Rules to follow when using local atomic operations
-- Variables touched by local ops must be per cpu variables.
-- _Only_ the CPU owner of these variables must write to them.
-- This CPU can use local ops from any context (process, irq, softirq, nmi, ...)
-  to update its local_t variables.
-- Preemption (or interrupts) must be disabled when using local ops in
-  process context to   make sure the process won't be migrated to a
-  different CPU between getting the per-cpu variable and doing the
-  actual local op.
-- When using local ops in interrupt context, no special care must be
-  taken on a mainline kernel, since they will run on the local CPU with
-  preemption already disabled. I suggest, however, to explicitly
-  disable preemption anyway to make sure it will still work correctly on
-  -rt kernels.
-- Reading the local cpu variable will provide the current copy of the
-  variable.
-- Reads of these variables can be done from any CPU, because updates to
-  "long", aligned, variables are always atomic. Since no memory
-  synchronization is done by the writer CPU, an outdated copy of the
-  variable can be read when reading some _other_ cpu's variables.
 * How to use local atomic operations
 #include <linux/percpu.h>
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