The patch titled
Subject: mm/mempolicy: remove or narrow the lock on current
has been added to the -mm tree. Its filename is
mm-mempolicy-remove-or-narrow-the-lock-on-current.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-mempolicy-remove-or-narrow-the-lock-on-current.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-mempolicy-remove-or-narrow-the-lock-on-current.patch
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------------------------------------------------------
From: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
Subject: mm/mempolicy: remove or narrow the lock on current
It is not necessary to hold the lock of current when setting nodemask of
a new policy.
Link: https://lkml.kernel.org/r/20200921040416.86185-1-richard.weiyang@xxxxxxxxxxxxxxxxx
Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mempolicy.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
--- a/mm/mempolicy.c~mm-mempolicy-remove-or-narrow-the-lock-on-current
+++ a/mm/mempolicy.c
@@ -875,13 +875,12 @@ static long do_set_mempolicy(unsigned sh
goto out;
}
- task_lock(current);
ret = mpol_set_nodemask(new, nodes, scratch);
if (ret) {
- task_unlock(current);
mpol_put(new);
goto out;
}
+ task_lock(current);
old = current->mempolicy;
current->mempolicy = new;
if (new && new->mode == MPOL_INTERLEAVE)
@@ -1324,9 +1323,7 @@ static long do_mbind(unsigned long start
NODEMASK_SCRATCH(scratch);
if (scratch) {
mmap_write_lock(mm);
- task_lock(current);
err = mpol_set_nodemask(new, nmask, scratch);
- task_unlock(current);
if (err)
mmap_write_unlock(mm);
} else
_
Patches currently in -mm which might be from richard.weiyang@xxxxxxxxxxxxxxxxx are
mm-mmap-rename-__vma_unlink_common-to-__vma_unlink.patch
mm-mmap-leverage-vma_rb_erase_ignore-to-implement-vma_rb_erase.patch
mm-mmap-leave-adjust_next-as-virtual-address-instead-of-page-frame-number.patch
mm-mmap-not-necessary-to-check-mapping-separately.patch
mm-mmap-check-on-file-instead-of-the-rb_root_cached-of-its-address_space.patch
mm-hugetlb-not-necessary-to-coalesce-regions-recursively.patch
mm-hugetlb-remove-vm_bug_onnrg-in-get_file_region_entry_from_cache.patch
mm-hugetlb-use-list_splice-to-merge-two-list-at-once.patch
mm-hugetlb-count-file_region-to-be-added-when-regions_needed-=-null.patch
mm-hugetlb-a-page-from-buddy-is-not-on-any-list.patch
mm-hugetlb-narrow-the-hugetlb_lock-protection-area-during-preparing-huge-page.patch
mm-hugetlb-take-the-free-hpage-during-the-iteration-directly.patch
mm-hugetlb-take-the-free-hpage-during-the-iteration-directly-v4.patch
mm-mempolicy-remove-or-narrow-the-lock-on-current.patch
mm-page_reporting-drop-stale-list-head-check-in-page_reporting_cycle.patch
bitops-simplify-get_count_order_long.patch
bitops-use-the-same-mechanism-for-get_count_order.patch
