diff options
Diffstat (limited to 'mm')
-rw-r--r-- | mm/mempolicy.c | 60 |
1 files changed, 30 insertions, 30 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 44dd9d1521ec..bda230e52acd 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c | |||
@@ -888,36 +888,36 @@ int do_migrate_pages(struct mm_struct *mm, | |||
888 | if (err) | 888 | if (err) |
889 | goto out; | 889 | goto out; |
890 | 890 | ||
891 | /* | 891 | /* |
892 | * Find a 'source' bit set in 'tmp' whose corresponding 'dest' | 892 | * Find a 'source' bit set in 'tmp' whose corresponding 'dest' |
893 | * bit in 'to' is not also set in 'tmp'. Clear the found 'source' | 893 | * bit in 'to' is not also set in 'tmp'. Clear the found 'source' |
894 | * bit in 'tmp', and return that <source, dest> pair for migration. | 894 | * bit in 'tmp', and return that <source, dest> pair for migration. |
895 | * The pair of nodemasks 'to' and 'from' define the map. | 895 | * The pair of nodemasks 'to' and 'from' define the map. |
896 | * | 896 | * |
897 | * If no pair of bits is found that way, fallback to picking some | 897 | * If no pair of bits is found that way, fallback to picking some |
898 | * pair of 'source' and 'dest' bits that are not the same. If the | 898 | * pair of 'source' and 'dest' bits that are not the same. If the |
899 | * 'source' and 'dest' bits are the same, this represents a node | 899 | * 'source' and 'dest' bits are the same, this represents a node |
900 | * that will be migrating to itself, so no pages need move. | 900 | * that will be migrating to itself, so no pages need move. |
901 | * | 901 | * |
902 | * If no bits are left in 'tmp', or if all remaining bits left | 902 | * If no bits are left in 'tmp', or if all remaining bits left |
903 | * in 'tmp' correspond to the same bit in 'to', return false | 903 | * in 'tmp' correspond to the same bit in 'to', return false |
904 | * (nothing left to migrate). | 904 | * (nothing left to migrate). |
905 | * | 905 | * |
906 | * This lets us pick a pair of nodes to migrate between, such that | 906 | * This lets us pick a pair of nodes to migrate between, such that |
907 | * if possible the dest node is not already occupied by some other | 907 | * if possible the dest node is not already occupied by some other |
908 | * source node, minimizing the risk of overloading the memory on a | 908 | * source node, minimizing the risk of overloading the memory on a |
909 | * node that would happen if we migrated incoming memory to a node | 909 | * node that would happen if we migrated incoming memory to a node |
910 | * before migrating outgoing memory source that same node. | 910 | * before migrating outgoing memory source that same node. |
911 | * | 911 | * |
912 | * A single scan of tmp is sufficient. As we go, we remember the | 912 | * A single scan of tmp is sufficient. As we go, we remember the |
913 | * most recent <s, d> pair that moved (s != d). If we find a pair | 913 | * most recent <s, d> pair that moved (s != d). If we find a pair |
914 | * that not only moved, but what's better, moved to an empty slot | 914 | * that not only moved, but what's better, moved to an empty slot |
915 | * (d is not set in tmp), then we break out then, with that pair. | 915 | * (d is not set in tmp), then we break out then, with that pair. |
916 | * Otherwise when we finish scannng from_tmp, we at least have the | 916 | * Otherwise when we finish scannng from_tmp, we at least have the |
917 | * most recent <s, d> pair that moved. If we get all the way through | 917 | * most recent <s, d> pair that moved. If we get all the way through |
918 | * the scan of tmp without finding any node that moved, much less | 918 | * the scan of tmp without finding any node that moved, much less |
919 | * moved to an empty node, then there is nothing left worth migrating. | 919 | * moved to an empty node, then there is nothing left worth migrating. |
920 | */ | 920 | */ |
921 | 921 | ||
922 | tmp = *from_nodes; | 922 | tmp = *from_nodes; |
923 | while (!nodes_empty(tmp)) { | 923 | while (!nodes_empty(tmp)) { |