Messages in this thread | | | From | "Huang, Ying" <> | Subject | Re: [PATCH 13/16] mm/migration: return errno when isolate_huge_page failed | Date | Wed, 09 Mar 2022 09:00:01 +0800 |
| |
Miaohe Lin <linmiaohe@huawei.com> writes:
> On 2022/3/7 13:07, Huang, Ying wrote: >> Miaohe Lin <linmiaohe@huawei.com> writes: >> >>> We should return errno (-EBUSY here) when failed to isolate the huge page >>> rather than always return 1 which could confuse the user. >>> >>> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> >>> --- >>> mm/migrate.c | 6 ++---- >>> 1 file changed, 2 insertions(+), 4 deletions(-) >>> >>> diff --git a/mm/migrate.c b/mm/migrate.c >>> index 6c2dfed2ddb8..279940c0c064 100644 >>> --- a/mm/migrate.c >>> +++ b/mm/migrate.c >>> @@ -1618,10 +1618,8 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, >>> goto out_putpage; >>> >>> if (PageHuge(page)) { >>> - if (PageHead(page)) { >>> - isolate_huge_page(page, pagelist); >>> - err = 1; >>> - } >>> + if (PageHead(page)) >>> + err = isolate_huge_page(page, pagelist) ? 1 : -EBUSY; >> >> IMHO, it's better to determine the proper errno inside >> isolate_huge_page() instead of in the caller. If you think it's >> necessary to get errno here. How about change isolate_huge_page() >> instead? > > IMO, -EBUSY should be enough for the user (as they could not do much) and this > errno keeps consistent with the non-hugetlb page case. What do you think?
I found the prototype of isolate_lru_page() is as follows,
int isolate_lru_page(struct page *page)
And it will return errno directly. I think we should follow same convention here?
Best Regards, Huang, Ying
| |