[4/5] mm/compaction: remove unnecessary cursor page in isolate_freepages_block
Commit Message
The cursor is only used for page forward currently. We can simply move page
forward directly to remove unnecessary cursor.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
---
mm/compaction.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
Comments
On 7/30/2023 1:43 AM, Kemeng Shi wrote:
> The cursor is only used for page forward currently. We can simply move page
> forward directly to remove unnecessary cursor.
>
> Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
LGTM.
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> ---
> mm/compaction.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/mm/compaction.c b/mm/compaction.c
> index 65791a74c5e8..cfb661f4ce23 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -589,7 +589,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
> bool strict)
> {
> int nr_scanned = 0, total_isolated = 0;
> - struct page *cursor;
> + struct page *page;
> unsigned long flags = 0;
> spinlock_t *locked = NULL;
> unsigned long blockpfn = *start_pfn;
> @@ -599,12 +599,11 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
> if (strict)
> stride = 1;
>
> - cursor = pfn_to_page(blockpfn);
> + page = pfn_to_page(blockpfn);
>
> /* Isolate free pages. */
> - for (; blockpfn < end_pfn; blockpfn += stride, cursor += stride) {
> + for (; blockpfn < end_pfn; blockpfn += stride, page += stride) {
> int isolated;
> - struct page *page = cursor;
>
> /*
> * Periodically drop the lock (if held) regardless of its
> @@ -628,7 +627,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
>
> if (likely(order <= MAX_ORDER)) {
> blockpfn += (1UL << order) - 1;
> - cursor += (1UL << order) - 1;
> + page += (1UL << order) - 1;
> nr_scanned += (1UL << order) - 1;
> }
> goto isolate_fail;
> @@ -665,7 +664,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
> }
> /* Advance to the end of split page */
> blockpfn += isolated - 1;
> - cursor += isolated - 1;
> + page += isolated - 1;
> continue;
>
> isolate_fail:
@@ -589,7 +589,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
bool strict)
{
int nr_scanned = 0, total_isolated = 0;
- struct page *cursor;
+ struct page *page;
unsigned long flags = 0;
spinlock_t *locked = NULL;
unsigned long blockpfn = *start_pfn;
@@ -599,12 +599,11 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
if (strict)
stride = 1;
- cursor = pfn_to_page(blockpfn);
+ page = pfn_to_page(blockpfn);
/* Isolate free pages. */
- for (; blockpfn < end_pfn; blockpfn += stride, cursor += stride) {
+ for (; blockpfn < end_pfn; blockpfn += stride, page += stride) {
int isolated;
- struct page *page = cursor;
/*
* Periodically drop the lock (if held) regardless of its
@@ -628,7 +627,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
if (likely(order <= MAX_ORDER)) {
blockpfn += (1UL << order) - 1;
- cursor += (1UL << order) - 1;
+ page += (1UL << order) - 1;
nr_scanned += (1UL << order) - 1;
}
goto isolate_fail;
@@ -665,7 +664,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
}
/* Advance to the end of split page */
blockpfn += isolated - 1;
- cursor += isolated - 1;
+ page += isolated - 1;
continue;
isolate_fail: