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| author | Alex Thorlton <athorlton@sgi.com> | 2014-04-08 00:37:10 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-08 01:35:52 +0200 |
| commit | a0715cc22601e8830ace98366c0c2bd8da52af52 (patch) | |
| tree | 4444c61a4685d10d683e1f29177a9e7cfbccae73 /kernel | |
| parent | mm: revert "thp: make MADV_HUGEPAGE check for mm->def_flags" (diff) | |
| download | linux-a0715cc22601e8830ace98366c0c2bd8da52af52.tar.xz linux-a0715cc22601e8830ace98366c0c2bd8da52af52.zip | |
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 <athorlton@sgi.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/fork.c | 11 | ||||
| -rw-r--r-- | kernel/sys.c | 15 |
2 files changed, 23 insertions, 3 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index abc45890f0a5..e40c0a01d5a6 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -530,8 +530,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p) atomic_set(&mm->mm_count, 1); init_rwsem(&mm->mmap_sem); INIT_LIST_HEAD(&mm->mmlist); - mm->flags = (current->mm) ? - (current->mm->flags & MMF_INIT_MASK) : default_dump_filter; mm->core_state = NULL; atomic_long_set(&mm->nr_ptes, 0); memset(&mm->rss_stat, 0, sizeof(mm->rss_stat)); @@ -540,8 +538,15 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p) mm_init_owner(mm, p); clear_tlb_flush_pending(mm); - if (likely(!mm_alloc_pgd(mm))) { + if (current->mm) { + mm->flags = current->mm->flags & MMF_INIT_MASK; + mm->def_flags = current->mm->def_flags & VM_INIT_DEF_MASK; + } else { + mm->flags = default_dump_filter; mm->def_flags = 0; + } + + if (likely(!mm_alloc_pgd(mm))) { mmu_notifier_mm_init(mm); return mm; } diff --git a/kernel/sys.c b/kernel/sys.c index adaeab6f7a87..fba0f29401ea 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1996,6 +1996,21 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, if (arg2 || arg3 || arg4 || arg5) return -EINVAL; return current->no_new_privs ? 1 : 0; + case PR_GET_THP_DISABLE: + if (arg2 || arg3 || arg4 || arg5) + return -EINVAL; + error = !!(me->mm->def_flags & VM_NOHUGEPAGE); + break; + case PR_SET_THP_DISABLE: + if (arg3 || arg4 || arg5) + return -EINVAL; + down_write(&me->mm->mmap_sem); + if (arg2) + me->mm->def_flags |= VM_NOHUGEPAGE; + else + me->mm->def_flags &= ~VM_NOHUGEPAGE; + up_write(&me->mm->mmap_sem); + break; default: error = -EINVAL; break; |