diff options
| author | Haggai Eran <haggaie@mellanox.com> | 2012-10-09 03:33:35 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-09 11:22:58 +0400 |
| commit | 6bdb913f0a70a4dfb7f066fb15e2d6f960701d00 (patch) | |
| tree | 9a61960b27bf801794104b8bb8fccee1813f1b4b /mm/memory.c | |
| parent | 2ec74c3ef2d8c58d71e0e00336fb6b891192155a (diff) | |
| download | linux-6bdb913f0a70a4dfb7f066fb15e2d6f960701d00.tar.xz | |
mm: wrap calls to set_pte_at_notify with invalidate_range_start and invalidate_range_end
In order to allow sleeping during invalidate_page mmu notifier calls, we
need to avoid calling when holding the PT lock. In addition to its direct
calls, invalidate_page can also be called as a substitute for a change_pte
call, in case the notifier client hasn't implemented change_pte.
This patch drops the invalidate_page call from change_pte, and instead
wraps all calls to change_pte with invalidate_range_start and
invalidate_range_end calls.
Note that change_pte still cannot sleep after this patch, and that clients
implementing change_pte should not take action on it in case the number of
outstanding invalidate_range_start calls is larger than one, otherwise
they might miss a later invalidation.
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Cc: Andrea Arcangeli <andrea@qumranet.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Haggai Eran <haggaie@mellanox.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Cc: Liran Liss <liranl@mellanox.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/mm/memory.c b/mm/memory.c index b03a4a21c1d0..01ec048ece8b 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2527,6 +2527,9 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, int ret = 0; int page_mkwrite = 0; struct page *dirty_page = NULL; + unsigned long mmun_start; /* For mmu_notifiers */ + unsigned long mmun_end; /* For mmu_notifiers */ + bool mmun_called = false; /* For mmu_notifiers */ old_page = vm_normal_page(vma, address, orig_pte); if (!old_page) { @@ -2704,6 +2707,11 @@ gotten: if (mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL)) goto oom_free_new; + mmun_start = address & PAGE_MASK; + mmun_end = (address & PAGE_MASK) + PAGE_SIZE; + mmun_called = true; + mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); + /* * Re-check the pte - we dropped the lock */ @@ -2766,14 +2774,12 @@ gotten: } else mem_cgroup_uncharge_page(new_page); + if (new_page) + page_cache_release(new_page); unlock: pte_unmap_unlock(page_table, ptl); - if (new_page) { - if (new_page == old_page) - /* cow happened, notify before releasing old_page */ - mmu_notifier_invalidate_page(mm, address); - page_cache_release(new_page); - } + if (mmun_called) + mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); if (old_page) { /* * Don't let another task, with possibly unlocked vma, |