From d5196996eb3f21f592bfb9d33be59adbb03b0d35 Mon Sep 17 00:00:00 2001
From: Andi Kleen <andi@firstfloor.org>
Date: Tue, 17 Nov 2009 14:06:22 -0800
Subject: [PATCH] --- yaml --- r: 168705 b: refs/heads/master c:
 6ad696d2cf535772dff659298ec7e7260e344595 h: refs/heads/master i:   168703:
 98fbea8ea5fda3786d867c9b576312c10fa85094 v: v3

---
 [refs]                        |  2 +-
 trunk/include/linux/suspend.h | 21 +++++++++++++++++++--
 trunk/mm/Kconfig              |  5 +----
 trunk/mm/memory_hotplug.c     | 21 +++++++++++++++++----
 4 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/[refs] b/[refs]
index b35da7a023f0..8122412cdc75 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9398180097e359646d46083c3e079a54e20bee82
+refs/heads/master: 6ad696d2cf535772dff659298ec7e7260e344595
diff --git a/trunk/include/linux/suspend.h b/trunk/include/linux/suspend.h
index cd15df6c63cd..5e781d824e6d 100644
--- a/trunk/include/linux/suspend.h
+++ b/trunk/include/linux/suspend.h
@@ -301,6 +301,8 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
 #define pm_notifier(fn, pri)	do { (void)(fn); } while (0)
 #endif /* !CONFIG_PM_SLEEP */
 
+extern struct mutex pm_mutex;
+
 #ifndef CONFIG_HIBERNATION
 static inline void register_nosave_region(unsigned long b, unsigned long e)
 {
@@ -308,8 +310,23 @@ static inline void register_nosave_region(unsigned long b, unsigned long e)
 static inline void register_nosave_region_late(unsigned long b, unsigned long e)
 {
 }
-#endif
 
-extern struct mutex pm_mutex;
+static inline void lock_system_sleep(void) {}
+static inline void unlock_system_sleep(void) {}
+
+#else
+
+/* Let some subsystems like memory hotadd exclude hibernation */
+
+static inline void lock_system_sleep(void)
+{
+	mutex_lock(&pm_mutex);
+}
+
+static inline void unlock_system_sleep(void)
+{
+	mutex_unlock(&pm_mutex);
+}
+#endif
 
 #endif /* _LINUX_SUSPEND_H */
diff --git a/trunk/mm/Kconfig b/trunk/mm/Kconfig
index fd3386242cf0..44cf6f0a3a6d 100644
--- a/trunk/mm/Kconfig
+++ b/trunk/mm/Kconfig
@@ -128,12 +128,9 @@ config SPARSEMEM_VMEMMAP
 config MEMORY_HOTPLUG
 	bool "Allow for memory hot-add"
 	depends on SPARSEMEM || X86_64_ACPI_NUMA
-	depends on HOTPLUG && !(HIBERNATION && !S390) && ARCH_ENABLE_MEMORY_HOTPLUG
+	depends on HOTPLUG && ARCH_ENABLE_MEMORY_HOTPLUG
 	depends on (IA64 || X86 || PPC_BOOK3S_64 || SUPERH || S390)
 
-comment "Memory hotplug is currently incompatible with Software Suspend"
-	depends on SPARSEMEM && HOTPLUG && HIBERNATION && !S390
-
 config MEMORY_HOTPLUG_SPARSE
 	def_bool y
 	depends on SPARSEMEM && MEMORY_HOTPLUG
diff --git a/trunk/mm/memory_hotplug.c b/trunk/mm/memory_hotplug.c
index 380aef45c2cf..2047465cd27c 100644
--- a/trunk/mm/memory_hotplug.c
+++ b/trunk/mm/memory_hotplug.c
@@ -26,6 +26,7 @@
 #include <linux/migrate.h>
 #include <linux/page-isolation.h>
 #include <linux/pfn.h>
+#include <linux/suspend.h>
 
 #include <asm/tlbflush.h>
 
@@ -485,14 +486,18 @@ int __ref add_memory(int nid, u64 start, u64 size)
 	struct resource *res;
 	int ret;
 
+	lock_system_sleep();
+
 	res = register_memory_resource(start, size);
+	ret = -EEXIST;
 	if (!res)
-		return -EEXIST;
+		goto out;
 
 	if (!node_online(nid)) {
 		pgdat = hotadd_new_pgdat(nid, start);
+		ret = -ENOMEM;
 		if (!pgdat)
-			return -ENOMEM;
+			goto out;
 		new_pgdat = 1;
 	}
 
@@ -515,7 +520,8 @@ int __ref add_memory(int nid, u64 start, u64 size)
 		BUG_ON(ret);
 	}
 
-	return ret;
+	goto out;
+
 error:
 	/* rollback pgdat allocation and others */
 	if (new_pgdat)
@@ -523,6 +529,8 @@ int __ref add_memory(int nid, u64 start, u64 size)
 	if (res)
 		release_memory_resource(res);
 
+out:
+	unlock_system_sleep();
 	return ret;
 }
 EXPORT_SYMBOL_GPL(add_memory);
@@ -759,6 +767,8 @@ int offline_pages(unsigned long start_pfn,
 	if (!test_pages_in_a_zone(start_pfn, end_pfn))
 		return -EINVAL;
 
+	lock_system_sleep();
+
 	zone = page_zone(pfn_to_page(start_pfn));
 	node = zone_to_nid(zone);
 	nr_pages = end_pfn - start_pfn;
@@ -766,7 +776,7 @@ int offline_pages(unsigned long start_pfn,
 	/* set above range as isolated */
 	ret = start_isolate_page_range(start_pfn, end_pfn);
 	if (ret)
-		return ret;
+		goto out;
 
 	arg.start_pfn = start_pfn;
 	arg.nr_pages = nr_pages;
@@ -844,6 +854,7 @@ int offline_pages(unsigned long start_pfn,
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_OFFLINE, &arg);
+	unlock_system_sleep();
 	return 0;
 
 failed_removal:
@@ -853,6 +864,8 @@ int offline_pages(unsigned long start_pfn,
 	/* pushback to free area */
 	undo_isolate_page_range(start_pfn, end_pfn);
 
+out:
+	unlock_system_sleep();
 	return ret;
 }