Re: [PATCH v2 2/4] mm: change to return bool for isolate_lru_page()
From: SeongJae Park <sj@kernel.org>
Date: 2023-02-14 19:32:18
Also in:
damon, linux-mm, lkml
On Tue, 14 Feb 2023 21:59:30 +0800 Baolin Wang [off-list ref] wrote:
The isolate_lru_page() can only return 0 or -EBUSY, and most users did not care about the negative error of isolate_lru_page(), except one user in add_page_for_migration(). So we can convert the isolate_lru_page() to return a boolean value, which can help to make the code more clear when checking the return value of isolate_lru_page(). Also convert all users' logic of checking the isolation state. No functional changes intended. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> --- mm/folio-compat.c | 12 +++--------- mm/internal.h | 2 +- mm/khugepaged.c | 2 +- mm/memcontrol.c | 4 ++-- mm/memory-failure.c | 4 ++-- mm/memory_hotplug.c | 2 +- mm/migrate.c | 9 ++++++--- mm/migrate_device.c | 2 +- 8 files changed, 17 insertions(+), 20 deletions(-)
[...]
quoted hunk ↗ jump to hunk
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index a1e8c3e9ab08..17ed80707518 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c@@ -1668,7 +1668,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) * LRU and non-lru movable pages. */ if (PageLRU(page)) - ret = isolate_lru_page(page); + ret = !isolate_lru_page(page);
This may change return value of this function. That is, this function will return 1 instead of -EBUSY after this change. It's not a real issue as no caller of this function takes care of the return value, though. Thanks, SJ
else
ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE);
if (!ret) { /* Success */[...]