[PATCH v1 4/6] mm/memory_hotplug: remove HIGHMEM leftovers

David Hildenbrand
2021-09-29T14:37:34Z

We don't support CONFIG_MEMORY_HOTPLUG on 32 bit and consequently not
HIGHMEM. Let's remove any leftover code -- including the unused
"status_change_nid_high" field part of the memory notifier.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
Documentation/core-api/memory-hotplug.rst | 3 --
.../zh_CN/core-api/memory-hotplug.rst | 4 ---
include/linux/memory.h | 1 -
mm/memory_hotplug.c | 36 ++-----------------
4 files changed, 2 insertions(+), 42 deletions(-)

diff --git a/Documentation/core-api/memory-hotplug.rst b/Documentation/core-api/memory-hotplug.rst
index de7467e48067..682259ee633a 100644
--- a/Documentation/core-api/memory-hotplug.rst
+++ b/Documentation/core-api/memory-hotplug.rst
@@ -57,7 +57,6 @@ The third argument (arg) passes a pointer of struct memory_notify::
unsigned long start_pfn;
unsigned long nr_pages;
int status_change_nid_normal;
- int status_change_nid_high;
int status_change_nid;
}

@@ -65,8 +64,6 @@ The third argument (arg) passes a pointer of struct memory_notify::
- nr_pages is # of pages of online/offline memory.
- status_change_nid_normal is set node id when N_NORMAL_MEMORY of nodemask
is (will be) set/clear, if this is -1, then nodemask status is not changed.
-- status_change_nid_high is set node id when N_HIGH_MEMORY of nodemask
- is (will be) set/clear, if this is -1, then nodemask status is not changed.
- status_change_nid is set node id when N_MEMORY of nodemask is (will be)
set/clear. It means a new(memoryless) node gets new memory by online and a
node loses all memory. If this is -1, then nodemask status is not changed.
diff --git a/Documentation/translations/zh_CN/core-api/memory-hotplug.rst b/Documentation/translations/zh_CN/core-api/memory-hotplug.rst
index 161f4d2c18cc..9a204eb196f2 100644
--- a/Documentation/translations/zh_CN/core-api/memory-hotplug.rst
+++ b/Documentation/translations/zh_CN/core-api/memory-hotplug.rst
@@ -63,7 +63,6 @@ memory_notify结构体的指针::
unsigned long start_pfn;
unsigned long nr_pages;
int status_change_nid_normal;
- int status_change_nid_high;
int status_change_nid;
}

@@ -74,9 +73,6 @@ memory_notify结构体的指针::
- status_change_nid_normal是当nodemask的N_NORMAL_MEMORY被设置/清除时设置节
点id，如果是-1，则nodemask状态不改变。

-- status_change_nid_high是当nodemask的N_HIGH_MEMORY被设置/清除时设置的节点
- id，如果这个值为-1，那么nodemask状态不会改变。
-
- status_change_nid是当nodemask的N_MEMORY被（将）设置/清除时设置的节点id。这
意味着一个新的（没上线的）节点通过联机获得新的内存，而一个节点失去了所有的内
存。如果这个值为-1，那么nodemask的状态就不会改变。
diff --git a/include/linux/memory.h b/include/linux/memory.h
index dd6e608c3e0b..c46ff374d48d 100644
--- a/include/linux/memory.h
+++ b/include/linux/memory.h
@@ -96,7 +96,6 @@ struct memory_notify {
unsigned long start_pfn;
unsigned long nr_pages;
int status_change_nid_normal;
- int status_change_nid_high;
int status_change_nid;
};

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 8d7b2b593a26..95c927c8bfb8 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -21,7 +21,6 @@
#include <linux/memory.h>
#include <linux/memremap.h>
#include <linux/memory_hotplug.h>
-#include <linux/highmem.h>
#include <linux/vmalloc.h>
#include <linux/ioport.h>
#include <linux/delay.h>
@@ -585,10 +584,6 @@ void generic_online_page(struct page *page, unsigned int order)
debug_pagealloc_map_pages(page, 1 << order);
__free_pages_core(page, order);
totalram_pages_add(1UL << order);
-#ifdef CONFIG_HIGHMEM
- if (PageHighMem(page))
- totalhigh_pages_add(1UL << order);
-#endif
}
EXPORT_SYMBOL_GPL(generic_online_page);

@@ -625,16 +620,11 @@ static void node_states_check_changes_online(unsigned long nr_pages,

arg->status_change_nid = NUMA_NO_NODE;
arg->status_change_nid_normal = NUMA_NO_NODE;
- arg->status_change_nid_high = NUMA_NO_NODE;

if (!node_state(nid, N_MEMORY))
arg->status_change_nid = nid;
if (zone_idx(zone) <= ZONE_NORMAL && !node_state(nid, N_NORMAL_MEMORY))
arg->status_change_nid_normal = nid;
-#ifdef CONFIG_HIGHMEM
- if (zone_idx(zone) <= ZONE_HIGHMEM && !node_state(nid, N_HIGH_MEMORY))
- arg->status_change_nid_high = nid;
-#endif
}

static void node_states_set_node(int node, struct memory_notify *arg)
@@ -642,9 +632,6 @@ static void node_states_set_node(int node, struct memory_notify *arg)
if (arg->status_change_nid_normal >= 0)
node_set_state(node, N_NORMAL_MEMORY);

- if (arg->status_change_nid_high >= 0)
- node_set_state(node, N_HIGH_MEMORY);
-
if (arg->status_change_nid >= 0)
node_set_state(node, N_MEMORY);
}
@@ -1801,7 +1788,6 @@ static void node_states_check_changes_offline(unsigned long nr_pages,

arg->status_change_nid = NUMA_NO_NODE;
arg->status_change_nid_normal = NUMA_NO_NODE;
- arg->status_change_nid_high = NUMA_NO_NODE;

/*
* Check whether node_states[N_NORMAL_MEMORY] will be changed.
@@ -1816,24 +1802,9 @@ static void node_states_check_changes_offline(unsigned long nr_pages,
if (zone_idx(zone) <= ZONE_NORMAL && nr_pages >= present_pages)
arg->status_change_nid_normal = zone_to_nid(zone);

-#ifdef CONFIG_HIGHMEM
- /*
- * node_states[N_HIGH_MEMORY] contains nodes which
- * have normal memory or high memory.
- * Here we add the present_pages belonging to ZONE_HIGHMEM.
- * If the zone is within the range of [0..ZONE_HIGHMEM), and
- * we determine that the zones in that range become empty,
- * we need to clear the node for N_HIGH_MEMORY.
- */
- present_pages += pgdat->node_zones[ZONE_HIGHMEM].present_pages;
- if (zone_idx(zone) <= ZONE_HIGHMEM && nr_pages >= present_pages)
- arg->status_change_nid_high = zone_to_nid(zone);
-#endif
-
/*
- * We have accounted the pages from [0..ZONE_NORMAL), and
- * in case of CONFIG_HIGHMEM the pages from ZONE_HIGHMEM
- * as well.
+ * We have accounted the pages from [0..ZONE_NORMAL); ZONE_HIGHMEM
+ * does not apply as we don't support 32bit.
* Here we count the possible pages from ZONE_MOVABLE.
* If after having accounted all the pages, we see that the nr_pages
* to be offlined is over or equal to the accounted pages,
@@ -1851,9 +1822,6 @@ static void node_states_clear_node(int node, struct memory_notify *arg)
if (arg->status_change_nid_normal >= 0)
node_clear_state(node, N_NORMAL_MEMORY);

- if (arg->status_change_nid_high >= 0)
- node_clear_state(node, N_HIGH_MEMORY);
-
if (arg->status_change_nid >= 0)
node_clear_state(node, N_MEMORY);
}
--
2.31.1