3 files changed, 11 insertions, 20 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 551f68bec2fa..e7e92c8f4883 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -770,7 +770,6 @@ static inline bool is_dev_zone(const struct zone *zone)
 
 #include <linux/memory_hotplug.h>
 
-extern struct mutex zonelists_mutex;
 void build_all_zonelists(pg_data_t *pgdat);
 void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx);
 bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 2f0c7ebc7624..73bf17df6899 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -897,7 +897,7 @@ static struct zone * __meminit move_pfn_range(int online_type, int nid,
         return zone;
 }
 
-/* Must be protected by mem_hotplug_begin() */
+/* Must be protected by mem_hotplug_begin() or a device_lock */
 int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
 {
         unsigned long flags;
@@ -926,7 +926,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
          * This means the page allocator ignores this zone.
          * So, zonelist must be updated after online.
          */
-        mutex_lock(&zonelists_mutex);
         if (!populated_zone(zone)) {
                 need_zonelists_rebuild = 1;
                 setup_zone_pageset(zone);
@@ -937,7 +936,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
         if (ret) {
                 if (need_zonelists_rebuild)
                         zone_pcp_reset(zone);
-                mutex_unlock(&zonelists_mutex);
                 goto failed_addition;
         }
 
@@ -955,8 +953,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
                         zone_pcp_update(zone);
         }
 
-        mutex_unlock(&zonelists_mutex);
-
         init_per_zone_wmark_min();
 
         if (onlined_pages) {
@@ -1027,9 +1023,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
          * The node we allocated has no zone fallback lists. For avoiding
          * to access not-initialized zonelist, build here.
          */
-        mutex_lock(&zonelists_mutex);
         build_all_zonelists(pgdat);
-        mutex_unlock(&zonelists_mutex);
 
         /*
          * zone->managed_pages is set to an approximate value in
@@ -1696,9 +1690,7 @@ repeat:
 
         if (!populated_zone(zone)) {
                 zone_pcp_reset(zone);
-                mutex_lock(&zonelists_mutex);
                 build_all_zonelists(NULL);
-                mutex_unlock(&zonelists_mutex);
         } else
                 zone_pcp_update(zone);
 
@@ -1724,7 +1716,7 @@ failed_removal:
         return ret;
 }
 
-/* Must be protected by mem_hotplug_begin() */
+/* Must be protected by mem_hotplug_begin() or a device_lock */
 int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 {
         return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e3086d0fd945..0bea94af0423 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5131,17 +5131,14 @@ static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
 static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
 static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
 
-/*
- * Global mutex to protect against size modification of zonelists
- * as well as to serialize pageset setup for the new populated zone.
- */
-DEFINE_MUTEX(zonelists_mutex);
-
 static void __build_all_zonelists(void *data)
 {
         int nid;
         int __maybe_unused cpu;
         pg_data_t *self = data;
+        static DEFINE_SPINLOCK(lock);
+
+        spin_lock(&lock);
 
 #ifdef CONFIG_NUMA
         memset(node_load, 0, sizeof(node_load));
@@ -5173,6 +5170,8 @@ static void __build_all_zonelists(void *data)
                         set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
 #endif
         }
+
+        spin_unlock(&lock);
 }
 
 static noinline void __init
@@ -5203,7 +5202,6 @@ build_all_zonelists_init(void)
 }
 
 /*
- * Called with zonelists_mutex held always
  * unless system_state == SYSTEM_BOOTING.
  *
  * __ref due to call of __init annotated helper build_all_zonelists_init
@@ -6939,9 +6937,11 @@ static void __setup_per_zone_wmarks(void)
  */
 void setup_per_zone_wmarks(void)
 {
-        mutex_lock(&zonelists_mutex);
+        static DEFINE_SPINLOCK(lock);
+
+        spin_lock(&lock);
         __setup_per_zone_wmarks();
-        mutex_unlock(&zonelists_mutex);
+        spin_unlock(&lock);
 }
 
 /*