mm, vmalloc: iterate vmap_area_list, instead of vmlist, in vmallocinfo()

This patch is a preparatory step for removing vmlist entirely.  For
above purpose, we change iterating a vmap_list codes to iterating a
vmap_area_list.  It is somewhat trivial change, but just one thing
should be noticed.

Using vmap_area_list in vmallocinfo() introduce ordering problem in SMP
system.  In s_show(), we retrieve some values from vm_struct.
vm_struct's values is not fully setup when va->vm is assigned.  Full
setup is notified by removing VM_UNLIST flag without holding a lock.
When we see that VM_UNLIST is removed, it is not ensured that vm_struct
has proper values in view of other CPUs.  So we need smp_[rw]mb for
ensuring that proper values is assigned when we see that VM_UNLIST is
removed.

Therefore, this patch not only change a iteration list, but also add a
appropriate smp_[rw]mb to right places.

Signed-off-by: Joonsoo Kim <[email protected]>
Signed-off-by: Joonsoo Kim <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Atsushi Kumagai <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Dave Anderson <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: Guan Xuetao <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Vivek Goyal <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions