The patch titled
Subject: mm/hugetlb: get rid of NODEMASK_ALLOC
has been added to the -mm tree. Its filename is
mm-hugetlb-get-rid-of-nodemask_alloc.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-get-rid-of-nodemask_alloc.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-get-rid-of-nodemask_alloc.patch
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The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: Oscar Salvador <osalvador@xxxxxxx>
Subject: mm/hugetlb: get rid of NODEMASK_ALLOC
NODEMASK_ALLOC is used to allocate a nodemask bitmap, and it does it by
first determining whether it should be allocated on the stack or
dynamically, depending on NODES_SHIFT. Right now, it goes the dynamic
path whenever the nodemask_t is above 32 bytes.
Although we could bump it to a reasonable value, the largest a nodemask_t
can get is 128 bytes, so since __nr_hugepages_store_common is called from
a rather short stack we can just get rid of the NODEMASK_ALLOC call here.
This reduces some code churn and complexity.
Link: http://lkml.kernel.org/r/20190402133415.21983-1-osalvador@xxxxxxx
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Alex Ghiti <alex@xxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Jing Xiangfeng <jingxiangfeng@xxxxxxxxxx>
Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/hugetlb.c | 36 +++++++++++-------------------------
1 file changed, 11 insertions(+), 25 deletions(-)
--- a/mm/hugetlb.c~mm-hugetlb-get-rid-of-nodemask_alloc
+++ a/mm/hugetlb.c
@@ -2447,44 +2447,30 @@ static ssize_t __nr_hugepages_store_comm
unsigned long count, size_t len)
{
int err;
- NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY);
+ nodemask_t nodes_allowed, *n_mask;
- if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) {
- err = -EINVAL;
- goto out;
- }
+ if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+ return -EINVAL;
if (nid == NUMA_NO_NODE) {
/*
* global hstate attribute
*/
if (!(obey_mempolicy &&
- init_nodemask_of_mempolicy(nodes_allowed))) {
- NODEMASK_FREE(nodes_allowed);
- nodes_allowed = &node_states[N_MEMORY];
- }
- } else if (nodes_allowed) {
+ init_nodemask_of_mempolicy(&nodes_allowed)))
+ n_mask = &node_states[N_MEMORY];
+ else
+ n_mask = &nodes_allowed;
+ } else {
/*
* Node specific request. count adjustment happens in
* set_max_huge_pages() after acquiring hugetlb_lock.
*/
- init_nodemask_of_node(nodes_allowed, nid);
- } else {
- /*
- * Node specific request, but we could not allocate the few
- * words required for a node mask. We are unlikely to hit
- * this condition. Since we can not pass down the appropriate
- * node mask, just return ENOMEM.
- */
- err = -ENOMEM;
- goto out;
+ init_nodemask_of_node(&nodes_allowed, nid);
+ n_mask = &nodes_allowed;
}
- err = set_max_huge_pages(h, count, nid, nodes_allowed);
-
-out:
- if (nodes_allowed != &node_states[N_MEMORY])
- NODEMASK_FREE(nodes_allowed);
+ err = set_max_huge_pages(h, count, nid, n_mask);
return err ? err : len;
}
_
Patches currently in -mm which might be from osalvador@xxxxxxx are
mmmemory_hotplug-unlock-1gb-hugetlb-on-x86_64.patch
mmmemory_hotplug-drop-redundant-hugepage_migration_supported-check.patch
mm-hugetlb-get-rid-of-nodemask_alloc.patch
