From a0715cc22601e8830ace98366c0c2bd8da52af52 Mon Sep 17 00:00:00 2001 From: Alex Thorlton Date: Mon, 7 Apr 2014 15:37:10 -0700 Subject: mm, thp: add VM_INIT_DEF_MASK and PRCTL_THP_DISABLE Add VM_INIT_DEF_MASK, to allow us to set the default flags for VMs. It also adds a prctl control which allows us to set the THP disable bit in mm->def_flags so that VMs will pick up the setting as they are created. Signed-off-by: Alex Thorlton Suggested-by: Oleg Nesterov Cc: Gerald Schaefer Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Christian Borntraeger Cc: Paolo Bonzini Cc: "Kirill A. Shutemov" Cc: Mel Gorman Acked-by: Rik van Riel Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Andrea Arcangeli Cc: Oleg Nesterov Cc: "Eric W. Biederman" Cc: Alexander Viro Cc: Johannes Weiner Cc: David Rientjes Cc: Paolo Bonzini Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 3 +++ include/uapi/linux/prctl.h | 3 +++ 2 files changed, 6 insertions(+) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 35300f390eb6..c270fa68a32b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -177,6 +177,9 @@ extern unsigned int kobjsize(const void *objp); */ #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) +/* This mask defines which mm->def_flags a process can inherit its parent */ +#define VM_INIT_DEF_MASK VM_NOHUGEPAGE + /* * mapping from the currently active vm_flags protection bits (the * low four bits) to a page protection mask.. diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 289760f424aa..58afc04c107e 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -149,4 +149,7 @@ #define PR_GET_TID_ADDRESS 40 +#define PR_SET_THP_DISABLE 41 +#define PR_GET_THP_DISABLE 42 + #endif /* _LINUX_PRCTL_H */ -- cgit v1.2.3-58-ga151