Messages in this thread | | | Date | Thu, 22 Apr 2010 14:20:23 -0700 (PDT) | From | David Rientjes <> | Subject | Re: [PATCH 1/2] mm: fix bugs of mpol_rebind_nodemask() |
| |
On Thu, 22 Apr 2010, Miao Xie wrote:
> - local variable might be an empty nodemask, so must be checked before setting > pol->v.nodes to it. > > - nodes_remap() may cause the weight of pol->v.nodes being monotonic decreasing. > and never become large even we pass a nodemask with large weight after > ->v.nodes become little. >
That's always been the intention of rebinding a mempolicy nodemask: we remap the current mempolicy nodes over the new nodemask given the set of allowed nodes. The nodes_remap() shouldn't be removed.
> this patch fixes these two problem. > > Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> > --- > mm/mempolicy.c | 9 ++++++--- > 1 files changed, 6 insertions(+), 3 deletions(-) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 08f40a2..03ba9fc 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -291,12 +291,15 @@ static void mpol_rebind_nodemask(struct mempolicy *pol, > else if (pol->flags & MPOL_F_RELATIVE_NODES) > mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes); > else { > - nodes_remap(tmp, pol->v.nodes, pol->w.cpuset_mems_allowed, > - *nodes); > + tmp = *nodes; > pol->w.cpuset_mems_allowed = *nodes; > } > > - pol->v.nodes = tmp; > + if (nodes_empty(tmp)) > + pol->v.nodes = *nodes; > + else > + pol->v.nodes = tmp; > + > if (!node_isset(current->il_next, tmp)) { > current->il_next = next_node(current->il_next, tmp); > if (current->il_next >= MAX_NUMNODES)
| |