mm: save some bytes in mm_struct by filling holes on 64bit

Save some bytes in mm_struct by filling holes

Putting int values together for better packing on 64bit shrinks sizeof(struct
mm_struct) from 776 bytes to 764 bytes.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index af190ceab9719dc68b148e3b22b05b28a54c64d2..29adaa781cb602b69cf471b4563edc6d827e89a9 100644 (file)
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -172,6 +172,7 @@ struct mm_struct {
        atomic_t mm_users;                      /* How many users with user space? */
        atomic_t mm_count;                      /* How many references to "struct mm_struct" (users count as 1) */
        int map_count;                          /* number of VMAs */
+       int core_waiters;
        struct rw_semaphore mmap_sem;
        spinlock_t page_table_lock;             /* Protects page tables and some counters */
 
@@ -216,11 +217,10 @@ struct mm_struct {
        unsigned long flags; /* Must use atomic bitops to access the bits */
 
        /* coredumping support */
-       int core_waiters;
        struct completion *core_startup_done, core_done;
 
        /* aio bits */
-       rwlock_t                ioctx_list_lock;
+       rwlock_t                ioctx_list_lock;        /* aio lock */
        struct kioctx           *ioctx_list;
 #ifdef CONFIG_CGROUP_MEM_RES_CTLR
        struct mem_cgroup *mem_cgroup;