diff options
| author | Vegard Nossum <vegard.nossum@oracle.com> | 2017-02-27 14:30:07 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-27 18:43:48 -0800 |
| commit | f1f1007644ffc8051a4c11427d58b1967ae7b75a (patch) | |
| tree | e7e590cb1baa494b963d81b967a3f98d3c56f33e /fs | |
| parent | 522b837c672eba9e9fb69f9f52bced0256dc6697 (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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/proc/base.c | 4 | ||||
| -rw-r--r-- | fs/userfaultfd.c | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index b8f06273353e..5d51a188871b 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -766,7 +766,7 @@ struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) if (!IS_ERR_OR_NULL(mm)) { /* ensure this mm_struct can't be freed */ - atomic_inc(&mm->mm_count); + mmgrab(mm); /* but do not pin its memory */ mmput(mm); } @@ -1064,7 +1064,7 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) if (p) { if (atomic_read(&p->mm->mm_users) > 1) { mm = p->mm; - atomic_inc(&mm->mm_count); + mmgrab(mm); } task_unlock(p); } diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index e6e0a619cb3a..3c421d06a18e 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1847,7 +1847,7 @@ static struct file *userfaultfd_file_create(int flags) ctx->released = false; ctx->mm = current->mm; /* prevent the mm struct to be freed */ - atomic_inc(&ctx->mm->mm_count); + mmgrab(ctx->mm); file = anon_inode_getfile("[userfaultfd]", &userfaultfd_fops, ctx, O_RDWR | (flags & UFFD_SHARED_FCNTL_FLAGS)); |