diff options
author | Vladimir Davydov <vdavydov@parallels.com> | 2014-08-08 23:21:58 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-09 00:57:23 +0200 |
commit | ce65cefa5debefc0e81d0a533bda467f0aa67350 (patch) | |
tree | 326946387f9add11f607bea19b2f8367de348e8e /kernel/fork.c | |
parent | fork/exec: cleanup mm initialization (diff) | |
download | linux-ce65cefa5debefc0e81d0a533bda467f0aa67350.tar.xz linux-ce65cefa5debefc0e81d0a533bda467f0aa67350.zip |
fork: reset mm->pinned_vm
mm->pinned_vm counts pages of mm's address space that were permanently
pinned in memory by increasing their reference counter. The counter was
introduced by commit bc3e53f682d9 ("mm: distinguish between mlocked and
pinned pages"), while before it locked_vm had been used for such pages.
Obviously, we should reset the counter on fork if !CLONE_VM, just like
we do with locked_vm, but currently we don't. Let's fix it.
This patch will fix the contents of /proc/pid/status:VmPin.
ib_umem_get[infiniband] and perf_mmap still check pinned_vm against
RLIMIT_MEMLOCK. It's left from the times when pinned pages were accounted
under locked_vm, but today it looks wrong. It isn't clear how we should
deal with it.
We still have some drivers accounting pinned pages under mm->locked_vm -
this is what commit bc3e53f682d9 was fighting against. It's
infiniband/usnic and vfio.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
-rw-r--r-- | kernel/fork.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 418b52a9ec6a..5a547a59a38a 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -543,6 +543,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p) atomic_long_set(&mm->nr_ptes, 0); mm->map_count = 0; mm->locked_vm = 0; + mm->pinned_vm = 0; memset(&mm->rss_stat, 0, sizeof(mm->rss_stat)); spin_lock_init(&mm->page_table_lock); mm_init_cpumask(mm); |