Re: [PATCH v4 9/9] mm/lru: revise the comments of lru_lock

From: Alex Shi
Date: Wed Nov 20 2019 - 06:49:09 EST




在 2019/11/20 上午12:19, Johannes Weiner 写道:
> On Tue, Nov 19, 2019 at 08:23:23PM +0800, Alex Shi wrote:
>> Since we changed the pgdat->lru_lock to lruvec->lru_lock, it's time to
>> fix the incorrect comments in code. Also fixed some zone->lru_lock comment
>> error from ancient time. etc.
>>
>> Originally-from: Hugh Dickins <hughd@xxxxxxxxxx>
>
> You can resubmit a patch written by somebody else, but you need to
> preserve authorship such that git can attribute it properly:
>
> From: Hugh Dickins <hughd@xxxxxxxxxx>
>
> in the patch header, as well as
>
> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
>
> in the changelog tags. It should look something like this:
>
> ---
> From: Hugh Dickins <hughd@xxxxxxxxxx>
> Subject: [PATCH] mm/memcg: update lru_lock Doc and comments
>
> Update scattered references from "zone_lru_lock" to "lruvec->lru_lock"
> (in low-level descriptions) or "lruvec lock" (where that reads better).
>
> In the course of doing so, update lock ordering comments in mm/rmap.c
> and mm/filemap.c and Documentation/cgroups/memory.txt - slightly, with
> no attempt to be complete (swap_lock, in particular, left out-of-date).
> Remove allusions to set_page_dirty under page_remove_rmap: gone in v3.9.
>
> memcg_test.txt looks quite out-of-date: just give LRU a short paragraph.
> Replaced zone by node throughout unevictable-lru.txt (except for stats).
> Leave Documentation/locking/lockstat.txt untouched this time: it doesn't
> matter if that still refers to zone->lru_lock, along with other history.
>
> I struggled to understand the comment above move_pages_to_lru() (surely
> it never calls page_referenced()), and eventually realized that most of
> it had got separated from shrink_active_list(): move that comment back.
>
> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
> ---
>

Thanks for teaching!