diff options
| author | Vegard Nossum <vegard.nossum@oracle.com> | 2017-02-08 10:44:11 +1100 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2017-02-17 16:03:17 +1100 |
| commit | 5ba8974f69c28a4cd3586d66e5c376760da0f94b (patch) | |
| tree | 5283f96299856f232e2e9f45b100f289742b93ba /kernel | |
| parent | 803d7fc24ac8eb2bd495eb271e0989b4c1803d3d (diff) | |
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 <vegard.nossum@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/exit.c | 2 | ||||
| -rw-r--r-- | kernel/futex.c | 2 | ||||
| -rw-r--r-- | kernel/sched/core.c | 4 |
3 files changed, 4 insertions, 4 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 90b09ca35c84..8a768a3672a5 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -539,7 +539,7 @@ static void exit_mm(void) __set_current_state(TASK_RUNNING); down_read(&mm->mmap_sem); } - atomic_inc(&mm->mm_count); + mmgrab(mm); BUG_ON(mm != current->active_mm); /* more a memory barrier than a real lock */ task_lock(current); diff --git a/kernel/futex.c b/kernel/futex.c index cdf365036141..b687cb22301c 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -338,7 +338,7 @@ static inline bool should_fail_futex(bool fshared) static inline void futex_get_mm(union futex_key *key) { - atomic_inc(&key->private.mm->mm_count); + mmgrab(key->private.mm); /* * Ensure futex_get_mm() implies a full barrier such that * get_futex_key() implies a full barrier. This is relied upon diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 34e2291a9a6c..c7ded3311ec4 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2844,7 +2844,7 @@ context_switch(struct rq *rq, struct task_struct *prev, if (!mm) { next->active_mm = oldmm; - atomic_inc(&oldmm->mm_count); + mmgrab(oldmm); enter_lazy_tlb(oldmm, next); } else switch_mm_irqs_off(oldmm, mm, next); @@ -6095,7 +6095,7 @@ void __init sched_init(void) /* * The boot idle thread does lazy MMU switching as well: */ - atomic_inc(&init_mm.mm_count); + mmgrab(&init_mm); enter_lazy_tlb(&init_mm, current); /* |