via-velocity: fix vlan receipt

[linux-2.6-omap-h63xx.git] / Documentation / vm / numa_memory_policy.txt

diff --git a/Documentation/vm/numa_memory_policy.txt b/Documentation/vm/numa_memory_policy.txt
index 8242f52d0f2294833373621ed061e1eebeb2acdd..dd49864979964f10ee097fd46779294e4b2cbe21 100644 (file)
--- a/Documentation/vm/numa_memory_policy.txt
+++ b/Documentation/vm/numa_memory_policy.txt
@@ -302,31 +302,30 @@ MEMORY POLICIES AND CPUSETS
 
 Memory policies work within cpusets as described above.  For memory policies
 that require a node or set of nodes, the nodes are restricted to the set of
 
 Memory policies work within cpusets as described above.  For memory policies
 that require a node or set of nodes, the nodes are restricted to the set of

-nodes whose memories are allowed by the cpuset constraints.  If the
-intersection of the set of nodes specified for the policy and the set of nodes
-allowed by the cpuset is the empty set, the policy is considered invalid and
-cannot be installed.
+nodes whose memories are allowed by the cpuset constraints.  If the nodemask
+specified for the policy contains nodes that are not allowed by the cpuset, or
+the intersection of the set of nodes specified for the policy and the set of
+nodes with memory is the empty set, the policy is considered invalid
+and cannot be installed.

 
 The interaction of memory policies and cpusets can be problematic for a
 couple of reasons:
 
 
 The interaction of memory policies and cpusets can be problematic for a
 couple of reasons:
 

-1) the memory policy APIs take physical node id's as arguments.  However, the
-   memory policy APIs do not provide a way to determine what nodes are valid
-   in the context where the application is running.  An application MAY consult
-   the cpuset file system [directly or via an out of tree, and not generally
-   available, libcpuset API] to obtain this information, but then the
-   application must be aware that it is running in a cpuset and use what are
-   intended primarily as administrative APIs.
-
-   However, as long as the policy specifies at least one node that is valid
-   in the controlling cpuset, the policy can be used.
+1) the memory policy APIs take physical node id's as arguments.  As mentioned
+   above, it is illegal to specify nodes that are not allowed in the cpuset.
+   The application must query the allowed nodes using the get_mempolicy()
+   API with the MPOL_F_MEMS_ALLOWED flag to determine the allowed nodes and
+   restrict itself to those nodes.  However, the resources available to a
+   cpuset can be changed by the system administrator, or a workload manager
+   application, at any time.  So, a task may still get errors attempting to
+   specify policy nodes, and must query the allowed memories again.

 
 2) when tasks in two cpusets share access to a memory region, such as shared
    memory segments created by shmget() of mmap() with the MAP_ANONYMOUS and
    MAP_SHARED flags, and any of the tasks install shared policy on the region,
    only nodes whose memories are allowed in both cpusets may be used in the
 
 2) when tasks in two cpusets share access to a memory region, such as shared
    memory segments created by shmget() of mmap() with the MAP_ANONYMOUS and
    MAP_SHARED flags, and any of the tasks install shared policy on the region,
    only nodes whose memories are allowed in both cpusets may be used in the

-   policies.  Again, obtaining this information requires "stepping outside"
-   the memory policy APIs, as well as knowing in what cpusets other task might
-   be attaching to the shared region, to use the cpuset information.
+   policies.  Obtaining this information requires "stepping outside" the
+   memory policy APIs to use the cpuset information and requires that one
+   know in what cpusets other task might be attaching to the shared region.

    Furthermore, if the cpusets' allowed memory sets are disjoint, "local"
    allocation is the only valid policy.
    Furthermore, if the cpusets' allowed memory sets are disjoint, "local"
    allocation is the only valid policy.