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Diffstat (limited to 'mm/memory_hotplug.c')
-rw-r--r--mm/memory_hotplug.c89
1 files changed, 15 insertions, 74 deletions
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 7cd4377ac83e..8dccc317aac2 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -52,32 +52,17 @@ static void generic_online_page(struct page *page);
static online_page_callback_t online_page_callback = generic_online_page;
static DEFINE_MUTEX(online_page_callback_lock);
-/* The same as the cpu_hotplug lock, but for memory hotplug. */
-static struct {
- struct task_struct *active_writer;
- struct mutex lock; /* Synchronizes accesses to refcount, */
- /*
- * Also blocks the new readers during
- * an ongoing mem hotplug operation.
- */
- int refcount;
+DEFINE_STATIC_PERCPU_RWSEM(mem_hotplug_lock);
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif
-} mem_hotplug = {
- .active_writer = NULL,
- .lock = __MUTEX_INITIALIZER(mem_hotplug.lock),
- .refcount = 0,
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- .dep_map = {.name = "mem_hotplug.lock" },
-#endif
-};
+void get_online_mems(void)
+{
+ percpu_down_read(&mem_hotplug_lock);
+}
-/* Lockdep annotations for get/put_online_mems() and mem_hotplug_begin/end() */
-#define memhp_lock_acquire_read() lock_map_acquire_read(&mem_hotplug.dep_map)
-#define memhp_lock_acquire() lock_map_acquire(&mem_hotplug.dep_map)
-#define memhp_lock_release() lock_map_release(&mem_hotplug.dep_map)
+void put_online_mems(void)
+{
+ percpu_up_read(&mem_hotplug_lock);
+}
bool movable_node_enabled = false;
@@ -99,60 +84,16 @@ static int __init setup_memhp_default_state(char *str)
}
__setup("memhp_default_state=", setup_memhp_default_state);
-void get_online_mems(void)
-{
- might_sleep();
- if (mem_hotplug.active_writer == current)
- return;
- memhp_lock_acquire_read();
- mutex_lock(&mem_hotplug.lock);
- mem_hotplug.refcount++;
- mutex_unlock(&mem_hotplug.lock);
-
-}
-
-void put_online_mems(void)
-{
- if (mem_hotplug.active_writer == current)
- return;
- mutex_lock(&mem_hotplug.lock);
-
- if (WARN_ON(!mem_hotplug.refcount))
- mem_hotplug.refcount++; /* try to fix things up */
-
- if (!--mem_hotplug.refcount && unlikely(mem_hotplug.active_writer))
- wake_up_process(mem_hotplug.active_writer);
- mutex_unlock(&mem_hotplug.lock);
- memhp_lock_release();
-
-}
-
-/* Serializes write accesses to mem_hotplug.active_writer. */
-static DEFINE_MUTEX(memory_add_remove_lock);
-
void mem_hotplug_begin(void)
{
- mutex_lock(&memory_add_remove_lock);
-
- mem_hotplug.active_writer = current;
-
- memhp_lock_acquire();
- for (;;) {
- mutex_lock(&mem_hotplug.lock);
- if (likely(!mem_hotplug.refcount))
- break;
- __set_current_state(TASK_UNINTERRUPTIBLE);
- mutex_unlock(&mem_hotplug.lock);
- schedule();
- }
+ cpus_read_lock();
+ percpu_down_write(&mem_hotplug_lock);
}
void mem_hotplug_done(void)
{
- mem_hotplug.active_writer = NULL;
- mutex_unlock(&mem_hotplug.lock);
- memhp_lock_release();
- mutex_unlock(&memory_add_remove_lock);
+ percpu_up_write(&mem_hotplug_lock);
+ cpus_read_unlock();
}
/* add this memory to iomem resource */
@@ -1725,7 +1666,7 @@ repeat:
goto failed_removal;
ret = 0;
if (drain) {
- lru_add_drain_all();
+ lru_add_drain_all_cpuslocked();
cond_resched();
drain_all_pages(zone);
}
@@ -1746,7 +1687,7 @@ repeat:
}
}
/* drain all zone's lru pagevec, this is asynchronous... */
- lru_add_drain_all();
+ lru_add_drain_all_cpuslocked();
yield();
/* drain pcp pages, this is synchronous. */
drain_all_pages(zone);