Messages in this thread | | | Subject | Re: [v2 PATCH] mm: move_pages: report the number of non-attempted pages | From | Yang Shi <> | Date | Thu, 23 Jan 2020 15:36:58 -0800 |
| |
On 1/23/20 2:59 PM, Wei Yang wrote: > On Thu, Jan 23, 2020 at 07:38:51AM +0800, Yang Shi wrote: >> Since commit a49bd4d71637 ("mm, numa: rework do_pages_move"), >> the semantic of move_pages() was changed to return the number of >> non-migrated pages (failed to migration) and the call would be aborted >> immediately if migrate_pages() returns positive value. But it didn't >> report the number of pages that we even haven't attempted to migrate. >> So, fix it by including non-attempted pages in the return value. >> >> Fixes: a49bd4d71637 ("mm, numa: rework do_pages_move") >> Suggested-by: Michal Hocko <mhocko@suse.com> >> Cc: Wei Yang <richardw.yang@linux.intel.com> >> Cc: <stable@vger.kernel.org> [4.17+] >> Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> >> --- >> v2: Rebased on top of the latest mainline kernel per Andrew >> >> mm/migrate.c | 24 ++++++++++++++++++++++-- >> 1 file changed, 22 insertions(+), 2 deletions(-) >> >> diff --git a/mm/migrate.c b/mm/migrate.c >> index 86873b6..9b8eb5d 100644 >> --- a/mm/migrate.c >> +++ b/mm/migrate.c >> @@ -1627,8 +1627,18 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, >> start = i; >> } else if (node != current_node) { >> err = do_move_pages_to_node(mm, &pagelist, current_node); >> - if (err) >> + if (err) { >> + /* >> + * Positive err means the number of failed >> + * pages to migrate. Since we are going to >> + * abort and return the number of non-migrated >> + * pages, so need incude the rest of the >> + * nr_pages that have not attempted as well. >> + */ >> + if (err > 0) >> + err += nr_pages - i - 1; >> goto out; >> + } >> err = store_status(status, start, current_node, i - start); >> if (err) >> goto out; >> @@ -1659,8 +1669,11 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, >> goto out_flush; >> >> err = do_move_pages_to_node(mm, &pagelist, current_node); >> - if (err) >> + if (err) { >> + if (err > 0) >> + err += nr_pages - i - 1; >> goto out; >> + } >> if (i > start) { >> err = store_status(status, start, current_node, i - start); >> if (err) >> @@ -1674,6 +1687,13 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, >> >> /* Make sure we do not overwrite the existing error */ >> err1 = do_move_pages_to_node(mm, &pagelist, current_node); >> + /* >> + * Don't have to report non-attempted pages here since: > In previous comment, you use "non-migrated". Here is "non-attempted". What's > the difference?
In that comment "non-migrated" includes both reported by migrate_pages() and the non-attempted.
> >> + * - If the above loop is done gracefully there is not non-attempted >> + * page. >> + * - If the above loop is aborted to it means more fatal error >> + * happened, should return err. >> + */ >> if (!err1) >> err1 = store_status(status, start, current_node, i - start); >> if (!err) >> -- >> 1.8.3.1
| |