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author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-01-16 01:54:00 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-16 02:56:32 +0100 |
commit | 4d2fa965483f4c39bd097ff9bbf3efe62d4cf367 (patch) | |
tree | d885a08dddf9a93e755ae02be7a4a3e012c09cd2 /mm | |
parent | thp: add option to setup migration entries during PMD split (diff) | |
download | linux-4d2fa965483f4c39bd097ff9bbf3efe62d4cf367.tar.xz linux-4d2fa965483f4c39bd097ff9bbf3efe62d4cf367.zip |
thp, mm: split_huge_page(): caller need to lock page
We're going to use migration entries instead of compound_lock() to
stabilize page refcounts. Setup and remove migration entries require
page to be locked.
Some of split_huge_page() callers already have the page locked. Let's
require everybody to lock the page before calling split_huge_page().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: 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 'mm')
-rw-r--r-- | mm/memory-failure.c | 8 | ||||
-rw-r--r-- | mm/migrate.c | 8 |
2 files changed, 13 insertions, 3 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 5b965e27aaae..a2c987df80eb 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1149,7 +1149,9 @@ int memory_failure(unsigned long pfn, int trapno, int flags) } if (!PageHuge(p) && PageTransHuge(hpage)) { + lock_page(hpage); if (!PageAnon(hpage) || unlikely(split_huge_page(hpage))) { + unlock_page(hpage); if (!PageAnon(hpage)) pr_err("MCE: %#lx: non anonymous thp\n", pfn); else @@ -1159,6 +1161,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags) put_hwpoison_page(p); return -EBUSY; } + unlock_page(hpage); VM_BUG_ON_PAGE(!page_count(p), p); hpage = compound_head(p); } @@ -1751,7 +1754,10 @@ int soft_offline_page(struct page *page, int flags) return -EBUSY; } if (!PageHuge(page) && PageTransHuge(hpage)) { - if (PageAnon(hpage) && unlikely(split_huge_page(hpage))) { + lock_page(page); + ret = split_huge_page(hpage); + unlock_page(page); + if (unlikely(ret)) { pr_info("soft offline: %#lx: failed to split THP\n", pfn); if (flags & MF_COUNT_INCREASED) diff --git a/mm/migrate.c b/mm/migrate.c index 91545da23fd1..dec81a9e2fd6 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -943,9 +943,13 @@ static ICE_noinline int unmap_and_move(new_page_t get_new_page, goto out; } - if (unlikely(PageTransHuge(page))) - if (unlikely(split_huge_page(page))) + if (unlikely(PageTransHuge(page))) { + lock_page(page); + rc = split_huge_page(page); + unlock_page(page); + if (rc) goto out; + } rc = __unmap_and_move(page, newpage, force, mode); if (rc == MIGRATEPAGE_SUCCESS) |