From f1f1007644ffc8051a4c11427d58b1967ae7b75a Mon Sep 17 00:00:00 2001 From: Vegard Nossum Date: Mon, 27 Feb 2017 14:30:07 -0800 Subject: mm: add new mmgrab() helper Apart from adding the helper function itself, the rest of the kernel is converted mechanically using: git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/' git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/' This is needed for a later patch that hooks into the helper, but might be a worthwhile cleanup on its own. (Michal Hocko provided most of the kerneldoc comment.) Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com Signed-off-by: Vegard Nossum Acked-by: Michal Hocko Acked-by: Peter Zijlstra (Intel) Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/khugepaged.c | 2 +- mm/ksm.c | 2 +- mm/mmu_context.c | 2 +- mm/mmu_notifier.c | 2 +- mm/oom_kill.c | 4 ++-- 5 files changed, 6 insertions(+), 6 deletions(-) (limited to 'mm') diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 77ae3239c3de..34bce5c308e3 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -420,7 +420,7 @@ int __khugepaged_enter(struct mm_struct *mm) list_add_tail(&mm_slot->mm_node, &khugepaged_scan.mm_head); spin_unlock(&khugepaged_mm_lock); - atomic_inc(&mm->mm_count); + mmgrab(mm); if (wakeup) wake_up_interruptible(&khugepaged_wait); diff --git a/mm/ksm.c b/mm/ksm.c index cf211c01ceac..520e4c37fec7 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -1854,7 +1854,7 @@ int __ksm_enter(struct mm_struct *mm) spin_unlock(&ksm_mmlist_lock); set_bit(MMF_VM_MERGEABLE, &mm->flags); - atomic_inc(&mm->mm_count); + mmgrab(mm); if (needs_wakeup) wake_up_interruptible(&ksm_thread_wait); diff --git a/mm/mmu_context.c b/mm/mmu_context.c index 6f4d27c5bb32..daf67bb02b4a 100644 --- a/mm/mmu_context.c +++ b/mm/mmu_context.c @@ -25,7 +25,7 @@ void use_mm(struct mm_struct *mm) task_lock(tsk); active_mm = tsk->active_mm; if (active_mm != mm) { - atomic_inc(&mm->mm_count); + mmgrab(mm); tsk->active_mm = mm; } tsk->mm = mm; diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index f4259e496f83..32bc9f2ff7eb 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -275,7 +275,7 @@ static int do_mmu_notifier_register(struct mmu_notifier *mn, mm->mmu_notifier_mm = mmu_notifier_mm; mmu_notifier_mm = NULL; } - atomic_inc(&mm->mm_count); + mmgrab(mm); /* * Serialize the update against mmu_notifier_unregister. A diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 578321f1c070..51c091849dcb 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -653,7 +653,7 @@ static void mark_oom_victim(struct task_struct *tsk) /* oom_mm is bound to the signal struct life time. */ if (!cmpxchg(&tsk->signal->oom_mm, NULL, mm)) - atomic_inc(&tsk->signal->oom_mm->mm_count); + mmgrab(tsk->signal->oom_mm); /* * Make sure that the task is woken up from uninterruptible sleep @@ -870,7 +870,7 @@ static void oom_kill_process(struct oom_control *oc, const char *message) /* Get a reference to safely compare mm after task_unlock(victim) */ mm = victim->mm; - atomic_inc(&mm->mm_count); + mmgrab(mm); /* * We should send SIGKILL before setting TIF_MEMDIE in order to prevent * the OOM victim from depleting the memory reserves from the user -- cgit v1.2.3-59-g8ed1b