From nfont@austin.ibm.com Tue Oct 19 10:58:51 2010 Message-ID: <4CBDD934.1070204@austin.ibm.com> Date: Tue, 19 Oct 2010 12:45:24 -0500 From: Nathan Fontenot To: Greg KH CC: Nathan Fontenot Subject: Driver core: Add mutex for adding/removing memory blocks Add a new mutex for use in adding and removing of memory blocks. This is needed to avoid any race conditions in which the same memory block could be added and removed at the same time. Signed-off-by: Nathan Fontenot Reviewed-by: Robin Holt Reviewed-By: KAMEZAWA Hiroyuki Signed-off-by: Greg Kroah-Hartman --- drivers/base/memory.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -27,6 +27,8 @@ #include #include +static DEFINE_MUTEX(mem_sysfs_mutex); + #define MEMORY_CLASS_NAME "memory" static struct sysdev_class memory_sysdev_class = { @@ -484,6 +486,8 @@ static int add_memory_block(int nid, str if (!mem) return -ENOMEM; + mutex_lock(&mem_sysfs_mutex); + mem->phys_index = __section_nr(section); mem->state = state; mutex_init(&mem->state_mutex); @@ -504,6 +508,7 @@ static int add_memory_block(int nid, str ret = register_mem_sect_under_node(mem, nid); } + mutex_unlock(&mem_sysfs_mutex); return ret; } @@ -512,6 +517,7 @@ int remove_memory_block(unsigned long no { struct memory_block *mem; + mutex_lock(&mem_sysfs_mutex); mem = find_memory_block(section); unregister_mem_sect_under_nodes(mem); mem_remove_simple_file(mem, phys_index); @@ -520,6 +526,7 @@ int remove_memory_block(unsigned long no mem_remove_simple_file(mem, removable); unregister_memory(mem, section); + mutex_unlock(&mem_sysfs_mutex); return 0; }