On 12/5/19 11:34 AM, Qian Cai wrote:
On Dec 5, 2019, at 2:27 PM, Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> wrote:
John noticed another return value inconsistency between the implementation and the manpage. The manpage says it should return -ENOENT if the page is already on the target node, but it doesn't. It looks the original code didn't return -ENOENT either, I'm not sure if this is a document issue or not. Anyway this is another issue, once we confirm it we can fix it later.
No, I think it is important to figure out this in the first place. Otherwise, it is pointless to touch this piece of code over and over again, i.e., this is not another issue but the core of this problem on hand.
As I said the status return value issue is a regression, but the -ENOENT
issue has been there since the syscall was introduced (The visual
inspection shows so I didn't actually run test against 2.6.x kernel, but
it returns 0 for >= 3.10 at least). It does need further clarification
(doc problem or code problem).
Michal also noticed several inconsistencies when he was reworking
move_pages(), and I agree with him that we'd better not touch them
without a clear usecase.