X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Flocal_ops.txt;h=4269a1105b378fafcc689435a2531b9d9d4287db;hb=13a6ddb08e58a1bd344da7898c4e2f13bdf18c2f;hp=1a45f11e645e978f445ba7396f0c5411a1695e06;hpb=febb187761b02fce7d61b9c897d0e701f672b5ee;p=linux-2.6

diff --git a/Documentation/local_ops.txt b/Documentation/local_ops.txt
index 1a45f11e64..4269a1105b 100644
--- a/Documentation/local_ops.txt
+++ b/Documentation/local_ops.txt
@@ -45,29 +45,6 @@ long fails. The definition looks like :
 typedef struct { atomic_long_t a; } local_t;
 
 
-* 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-  synchronization is done by the writer CPU, an outdated copy of the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.
-
-
 * Rules to follow when using local atomic operations
 
 - Variables touched by local ops must be per cpu variables.