Re: [PATCH v4] mm/damon: simplify scheme create in lru_sort.c

[haoxin <xhao@xxxxxxxxxxxxxxxxx>]

Reviewed-by: Xin Hao <xhao@xxxxxxxxxxxxxxxxx>

Thanks.

在 2022/9/15 下午9:30, SeongJae Park 写道:
> From: Xin Hao <xhao@xxxxxxxxxxxxxxxxx>
>
> In damon_lru_sort_new_hot_scheme() and damon_lru_sort_new_cold_scheme(),
> they have so much in common, so we can combine them into a single
> function, and we just need to distinguish their differences.
>
> Suggested-by: SeongJae Park <sj@xxxxxxxxxx>
> Signed-off-by: Xin Hao <xhao@xxxxxxxxxxxxxxxxx>
> Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
> ---
> changes from v3
> (https://lore.kernel.org/damon/20220915023655.41923-1-xhao@xxxxxxxxxxxxxxxxx/)
> - Cosmetic cleanups
>
> Changes from v2
> (https://lore.kernel.org/linux-mm/20220914113859.37637-1-xhao@xxxxxxxxxxxxxxxxx/)
> - Add static global 'struct damos_access_pattern' stub variable
>
>   mm/damon/lru_sort.c | 39 +++++++++++++++++----------------------
>   1 file changed, 17 insertions(+), 22 deletions(-)
>
> diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
> index 46e7c0738bc5..abfaf471e3e9 100644
> --- a/mm/damon/lru_sort.c
> +++ b/mm/damon/lru_sort.c
> @@ -132,6 +132,18 @@ DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_lru_sort_cold_stat,
>   		lru_sort_tried_cold_regions, lru_sorted_cold_regions,
>   		cold_quota_exceeds);
>   
> +struct damos_access_pattern damon_lru_sort_stub_pattern = {
> +	/* Find regions having PAGE_SIZE or larger size */
> +	.min_sz_region = PAGE_SIZE,
> +	.max_sz_region = ULONG_MAX,
> +	/* no matter its access frequency */
> +	.min_nr_accesses = 0,
> +	.max_nr_accesses = UINT_MAX,
> +	/* no matter its age */
> +	.min_age_region = 0,
> +	.max_age_region = UINT_MAX,
> +};
> +
>   static struct damon_ctx *ctx;
>   static struct damon_target *target;
>   
> @@ -157,36 +169,19 @@ static struct damos *damon_lru_sort_new_scheme(
>   /* Create a DAMON-based operation scheme for hot memory regions */
>   static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres)
>   {
> -	struct damos_access_pattern pattern = {
> -		/* Find regions having PAGE_SIZE or larger size */
> -		.min_sz_region = PAGE_SIZE,
> -		.max_sz_region = ULONG_MAX,
> -		/* and accessed for more than the threshold */
> -		.min_nr_accesses = hot_thres,
> -		.max_nr_accesses = UINT_MAX,
> -		/* no matter its age */
> -		.min_age_region = 0,
> -		.max_age_region = UINT_MAX,
> -	};
> +	struct damos_access_pattern pattern = damon_lru_sort_stub_pattern;
>   
> +	pattern.min_nr_accesses = hot_thres;
>   	return damon_lru_sort_new_scheme(&pattern, DAMOS_LRU_PRIO);
>   }
>   
>   /* Create a DAMON-based operation scheme for cold memory regions */
>   static struct damos *damon_lru_sort_new_cold_scheme(unsigned int cold_thres)
>   {
> -	struct damos_access_pattern pattern = {
> -		/* Find regions having PAGE_SIZE or larger size */
> -		.min_sz_region = PAGE_SIZE,
> -		.max_sz_region = ULONG_MAX,
> -		/* and not accessed at all */
> -		.min_nr_accesses = 0,
> -		.max_nr_accesses = 0,
> -		/* for min_age or more micro-seconds */
> -		.min_age_region = cold_thres,
> -		.max_age_region = UINT_MAX,
> -	};
> +	struct damos_access_pattern pattern = damon_lru_sort_stub_pattern;
>   
> +	pattern.max_nr_accesses = 0;
> +	pattern.min_age_region = cold_thres;
>   	return damon_lru_sort_new_scheme(&pattern, DAMOS_LRU_DEPRIO);
>   }
>