mm, shmem: fix handling /sys/kernel/mm/transparent_hugepage/shmem_enabled

/sys/kernel/mm/transparent_hugepage/shmem_enabled controls if we want
to allocate huge pages when allocate pages for private in-kernel shmem
mount.

Unfortunately, as Dan noticed, I've screwed it up and the only way to
make kernel allocate huge page for the mount is to use "force" there.
All other values will be effectively ignored.

Link: http://lkml.kernel.org/r/20170822144254.66431-1-kirill.shutemov@linux.intel.com
Fixes: 5a6e75f811 ("shmem: prepare huge= mount option and sysfs knob")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Kirill A. Shutemov 2017-08-25 15:55:33 -07:00 committed by Linus Torvalds
parent 556b969a1c
commit 435c0b87d6

View File

@ -3967,7 +3967,7 @@ int __init shmem_init(void)
}
#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE
if (has_transparent_hugepage() && shmem_huge < SHMEM_HUGE_DENY)
if (has_transparent_hugepage() && shmem_huge > SHMEM_HUGE_DENY)
SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge;
else
shmem_huge = 0; /* just in case it was patched */
@ -4028,7 +4028,7 @@ static ssize_t shmem_enabled_store(struct kobject *kobj,
return -EINVAL;
shmem_huge = huge;
if (shmem_huge < SHMEM_HUGE_DENY)
if (shmem_huge > SHMEM_HUGE_DENY)
SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge;
return count;
}