diff options
Diffstat (limited to 'mm/init-mm.c')
| -rw-r--r-- | mm/init-mm.c | 11 | 
1 files changed, 11 insertions, 0 deletions
| diff --git a/mm/init-mm.c b/mm/init-mm.c index f0179c9c04c2..a787a319211e 100644 --- a/mm/init-mm.c +++ b/mm/init-mm.c @@ -15,6 +15,16 @@  #define INIT_MM_CONTEXT(name)  #endif +/* + * For dynamically allocated mm_structs, there is a dynamically sized cpumask + * at the end of the structure, the size of which depends on the maximum CPU + * number the system can see. That way we allocate only as much memory for + * mm_cpumask() as needed for the hundreds, or thousands of processes that + * a system typically runs. + * + * Since there is only one init_mm in the entire system, keep it simple + * and size this cpu_bitmask to NR_CPUS. + */  struct mm_struct init_mm = {  	.mm_rb		= RB_ROOT,  	.pgd		= swapper_pg_dir, @@ -25,5 +35,6 @@ struct mm_struct init_mm = {  	.arg_lock	=  __SPIN_LOCK_UNLOCKED(init_mm.arg_lock),  	.mmlist		= LIST_HEAD_INIT(init_mm.mmlist),  	.user_ns	= &init_user_ns, +	.cpu_bitmap	= { [BITS_TO_LONGS(NR_CPUS)] = 0},  	INIT_MM_CONTEXT(init_mm)  }; |