mm, oom: avoid reaping only for mm's with blockable invalidate callbacks

This uses the new annotation to determine if an mm has mmu notifiers
with blockable invalidate range callbacks to avoid oom reaping.
Otherwise, the callbacks are used around unmap_page_range().

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1712141330120.74052@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Oded Gabbay <oded.gabbay@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Rientjes 2018-01-31 16:18:36 -08:00 committed by Linus Torvalds
parent 5ff7091f5a
commit f340ff8203
1 changed files with 11 additions and 10 deletions

View File

@ -514,15 +514,12 @@ static bool __oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm)
} }
/* /*
* If the mm has notifiers then we would need to invalidate them around * If the mm has invalidate_{start,end}() notifiers that could block,
* unmap_page_range and that is risky because notifiers can sleep and
* what they do is basically undeterministic. So let's have a short
* sleep to give the oom victim some more time. * sleep to give the oom victim some more time.
* TODO: we really want to get rid of this ugly hack and make sure that * TODO: we really want to get rid of this ugly hack and make sure that
* notifiers cannot block for unbounded amount of time and add * notifiers cannot block for unbounded amount of time
* mmu_notifier_invalidate_range_{start,end} around unmap_page_range
*/ */
if (mm_has_notifiers(mm)) { if (mm_has_blockable_invalidate_notifiers(mm)) {
up_read(&mm->mmap_sem); up_read(&mm->mmap_sem);
schedule_timeout_idle(HZ); schedule_timeout_idle(HZ);
goto unlock_oom; goto unlock_oom;
@ -565,10 +562,14 @@ static bool __oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm)
* count elevated without a good reason. * count elevated without a good reason.
*/ */
if (vma_is_anonymous(vma) || !(vma->vm_flags & VM_SHARED)) { if (vma_is_anonymous(vma) || !(vma->vm_flags & VM_SHARED)) {
tlb_gather_mmu(&tlb, mm, vma->vm_start, vma->vm_end); const unsigned long start = vma->vm_start;
unmap_page_range(&tlb, vma, vma->vm_start, vma->vm_end, const unsigned long end = vma->vm_end;
NULL);
tlb_finish_mmu(&tlb, vma->vm_start, vma->vm_end); tlb_gather_mmu(&tlb, mm, start, end);
mmu_notifier_invalidate_range_start(mm, start, end);
unmap_page_range(&tlb, vma, start, end, NULL);
mmu_notifier_invalidate_range_end(mm, start, end);
tlb_finish_mmu(&tlb, start, end);
} }
} }
pr_info("oom_reaper: reaped process %d (%s), now anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n", pr_info("oom_reaper: reaped process %d (%s), now anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n",