summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/admin-guide/mm/numa_memory_policy.rst15
-rw-r--r--mm/mempolicy.c7
2 files changed, 12 insertions, 10 deletions
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index 067a90a1499c..64fd0ba0d057 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -245,6 +245,13 @@ MPOL_INTERLEAVED
address range or file. During system boot up, the temporary
interleaved system default policy works in this mode.
+MPOL_PREFERRED_MANY
+ This mode specifices that the allocation should be preferrably
+ satisfied from the nodemask specified in the policy. If there is
+ a memory pressure on all nodes in the nodemask, the allocation
+ can fall back to all existing numa nodes. This is effectively
+ MPOL_PREFERRED allowed for a mask rather than a single node.
+
NUMA memory policy supports the following optional mode flags:
MPOL_F_STATIC_NODES
@@ -253,10 +260,10 @@ MPOL_F_STATIC_NODES
nodes changes after the memory policy has been defined.
Without this flag, any time a mempolicy is rebound because of a
- change in the set of allowed nodes, the node (Preferred) or
- nodemask (Bind, Interleave) is remapped to the new set of
- allowed nodes. This may result in nodes being used that were
- previously undesired.
+ change in the set of allowed nodes, the preferred nodemask (Preferred
+ Many), preferred node (Preferred) or nodemask (Bind, Interleave) is
+ remapped to the new set of allowed nodes. This may result in nodes
+ being used that were previously undesired.
With this flag, if the user-specified nodes overlap with the
nodes allowed by the task's cpuset, then the memory policy is
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 64be3565ab7f..9e58854d7929 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1463,12 +1463,7 @@ static inline int sanitize_mpol_flags(int *mode, unsigned short *flags)
*flags = *mode & MPOL_MODE_FLAGS;
*mode &= ~MPOL_MODE_FLAGS;
- /*
- * The check should be 'mode >= MPOL_MAX', but as 'prefer_many'
- * is not fully implemented, don't permit it to be used for now,
- * and the logic will be restored in following patch
- */
- if ((unsigned int)(*mode) >= MPOL_PREFERRED_MANY)
+ if ((unsigned int)(*mode) >= MPOL_MAX)
return -EINVAL;
if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES))
return -EINVAL;