diff options
| author | Jia He <hejianet@gmail.com> | 2016-08-02 14:02:31 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-08-20 18:09:24 +0200 |
| commit | 4733b66d45d4452155a123b12dfeba3edba0facd (patch) | |
| tree | 6ca1400d8aa7472a0b89a0b8795e890ce8945e70 | |
| parent | 7928de5185f04b970dc9505cb8caa1cb5e46fa07 (diff) | |
mm/hugetlb: avoid soft lockup in set_max_huge_pages()
commit 649920c6ab93429b94bc7c1aa7c0e8395351be32 upstream.
In powerpc servers with large memory(32TB), we watched several soft
lockups for hugepage under stress tests.
The call traces are as follows:
1.
get_page_from_freelist+0x2d8/0xd50
__alloc_pages_nodemask+0x180/0xc20
alloc_fresh_huge_page+0xb0/0x190
set_max_huge_pages+0x164/0x3b0
2.
prep_new_huge_page+0x5c/0x100
alloc_fresh_huge_page+0xc8/0x190
set_max_huge_pages+0x164/0x3b0
This patch fixes such soft lockups. It is safe to call cond_resched()
there because it is out of spin_lock/unlock section.
Link: http://lkml.kernel.org/r/1469674442-14848-1-git-send-email-hejianet@gmail.com
Signed-off-by: Jia He <hejianet@gmail.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | mm/hugetlb.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ef6963b577fd..0c31f184daf8 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2170,6 +2170,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, * and reducing the surplus. */ spin_unlock(&hugetlb_lock); + + /* yield cpu to avoid soft lockup */ + cond_resched(); + if (hstate_is_gigantic(h)) ret = alloc_fresh_gigantic_page(h, nodes_allowed); else |