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Message-ID: <1beedefc-bbcc-3161-a44b-8056666d5dee@linux.alibaba.com>
Date:   Thu, 8 Sep 2022 10:27:21 +0800
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Subject: Re: [PATCH V2] mm/damon: Remove duplicate get_monitoring_region()
 definitions
To:     sj@kernel.org
Cc:     akpm@linux-foundation.org, damon@lists.linux.dev,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20220908021544.70212-1-xhao@linux.alibaba.com>
From:   haoxin <xhao@linux.alibaba.com>
In-Reply-To: <20220908021544.70212-1-xhao@linux.alibaba.com>
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在 2022/9/8 上午10:15, Xin Hao 写道:
> In lru_sort.c and reclaim.c, they are all defining get_monitoring_region()
> function, there is no need to define it separately.
>
> BTW, this patch removes two struct 'damon_lru_sort_ram_walk_arg' and
> 'damon_reclaim_ram_walk_arg', though the two structs are removed, if we
> want to add more fields to these structs for other purposes later, it will
> not too late for us to use them again.
> For example:
>      struct damon_reclaim_ram_walk_arg {
> 	struct damon_addr_range raw_walk;
> 	xxx  A;
> 	xxx  B;
>      }
>      struct damon_lru_sort_ram_walk_arg {
> 	struct damon_addr_range raw_walk;
> 	xxx  A;
> 	xxx  B;
>      }
>
> Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
> ---
>   include/linux/damon.h |  1 +
>   mm/damon/core.c       | 28 ++++++++++++++++++++++++++++
>   mm/damon/lru_sort.c   | 37 ++-----------------------------------
>   mm/damon/ops-common.h |  1 +
>   mm/damon/reclaim.c    | 37 ++-----------------------------------
>   5 files changed, 34 insertions(+), 70 deletions(-)
>
> diff --git a/include/linux/damon.h b/include/linux/damon.h
> index 7b1f4a488230..f27b92e5afc2 100644
> --- a/include/linux/damon.h
> +++ b/include/linux/damon.h
> @@ -500,6 +500,7 @@ void damon_add_region(struct damon_region *r, struct damon_target *t);
>   void damon_destroy_region(struct damon_region *r, struct damon_target *t);
>   int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges,
>   		unsigned int nr_ranges);
> +bool damon_get_sram_monitoring_region(unsigned long *start, unsigned long *end);
>   
>   struct damos *damon_new_scheme(
>   		unsigned long min_sz_region, unsigned long max_sz_region,
> diff --git a/mm/damon/core.c b/mm/damon/core.c
> index 7d25dc582fe3..05a2d1b9d03d 100644
> --- a/mm/damon/core.c
> +++ b/mm/damon/core.c
> @@ -276,6 +276,34 @@ struct damos *damon_new_scheme(
>   	return scheme;
>   }
>   
> +static inline int walk_system_ram(struct resource *res, void *arg)
> +{
> +	struct damon_addr_range *a = arg;
> +
> +	if (a->end - a->start < resource_size(res)) {
> +		a->start = res->start;
> +		a->end = res->end;
> +	}
> +	return 0;
> +}
> +
> +/*
> + * Find biggest 'System RAM' resource and store its start and end address in
> + * @start and @end, respectively.  If no System RAM is found, returns false.
> + */
> +bool damon_get_sram_monitoring_region(unsigned long *start, unsigned long *end)
> +{
> +	struct damon_addr_range arg = {};
> +
> +	walk_system_ram_res(0, ULONG_MAX, &arg, walk_system_ram);
> +	if (arg.end <= arg.start)
> +		return false;
> +
> +	*start = arg.start;
> +	*end = arg.end;
> +	return true;
> +}
> +
>   void damon_add_scheme(struct damon_ctx *ctx, struct damos *s)
>   {
>   	list_add_tail(&s->list, &ctx->schemes);
> diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
> index 9de6f00a71c5..cbe7e865dc74 100644
> --- a/mm/damon/lru_sort.c
> +++ b/mm/damon/lru_sort.c
> @@ -257,39 +257,6 @@ module_param(nr_cold_quota_exceeds, ulong, 0400);
>   static struct damon_ctx *ctx;
>   static struct damon_target *target;
>   
> -struct damon_lru_sort_ram_walk_arg {
> -	unsigned long start;
> -	unsigned long end;
> -};
> -
> -static int walk_system_ram(struct resource *res, void *arg)
> -{
> -	struct damon_lru_sort_ram_walk_arg *a = arg;
> -
> -	if (a->end - a->start < resource_size(res)) {
> -		a->start = res->start;
> -		a->end = res->end;
> -	}
> -	return 0;
> -}
> -
> -/*
> - * Find biggest 'System RAM' resource and store its start and end address in
> - * @start and @end, respectively.  If no System RAM is found, returns false.
> - */
> -static bool get_monitoring_region(unsigned long *start, unsigned long *end)
> -{
> -	struct damon_lru_sort_ram_walk_arg arg = {};
> -
> -	walk_system_ram_res(0, ULONG_MAX, &arg, walk_system_ram);
> -	if (arg.end <= arg.start)
> -		return false;
> -
> -	*start = arg.start;
> -	*end = arg.end;
> -	return true;
> -}
> -
>   /* Create a DAMON-based operation scheme for hot memory regions */
>   static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres)
>   {
> @@ -404,8 +371,8 @@ static int damon_lru_sort_apply_parameters(void)
>   	if (monitor_region_start > monitor_region_end)
>   		return -EINVAL;
>   	if (!monitor_region_start && !monitor_region_end &&
> -			!get_monitoring_region(&monitor_region_start,
> -				&monitor_region_end))
> +	    !damon_get_sram_monitoring_region(&monitor_region_start,
> +					      &monitor_region_end))
>   		return -EINVAL;
>   	addr_range.start = monitor_region_start;
>   	addr_range.end = monitor_region_end;
> diff --git a/mm/damon/ops-common.h b/mm/damon/ops-common.h
> index 52329ff361cd..e6f1c9b48042 100644
> --- a/mm/damon/ops-common.h
> +++ b/mm/damon/ops-common.h
> @@ -16,3 +16,4 @@ int damon_pageout_score(struct damon_ctx *c, struct damon_region *r,
>   			struct damos *s);
>   int damon_hot_score(struct damon_ctx *c, struct damon_region *r,
>   			struct damos *s);
> +bool get_monitoring_region(unsigned long *start, unsigned long *end);
There should be removed,  please ignore this patch, i will send a V3 
patch,  thanks.
> diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
> index a7faf51b4bd4..484bb802d249 100644
> --- a/mm/damon/reclaim.c
> +++ b/mm/damon/reclaim.c
> @@ -229,39 +229,6 @@ module_param(nr_quota_exceeds, ulong, 0400);
>   static struct damon_ctx *ctx;
>   static struct damon_target *target;
>   
> -struct damon_reclaim_ram_walk_arg {
> -	unsigned long start;
> -	unsigned long end;
> -};
> -
> -static int walk_system_ram(struct resource *res, void *arg)
> -{
> -	struct damon_reclaim_ram_walk_arg *a = arg;
> -
> -	if (a->end - a->start < resource_size(res)) {
> -		a->start = res->start;
> -		a->end = res->end;
> -	}
> -	return 0;
> -}
> -
> -/*
> - * Find biggest 'System RAM' resource and store its start and end address in
> - * @start and @end, respectively.  If no System RAM is found, returns false.
> - */
> -static bool get_monitoring_region(unsigned long *start, unsigned long *end)
> -{
> -	struct damon_reclaim_ram_walk_arg arg = {};
> -
> -	walk_system_ram_res(0, ULONG_MAX, &arg, walk_system_ram);
> -	if (arg.end <= arg.start)
> -		return false;
> -
> -	*start = arg.start;
> -	*end = arg.end;
> -	return true;
> -}
> -
>   static struct damos *damon_reclaim_new_scheme(void)
>   {
>   	struct damos_watermarks wmarks = {
> @@ -323,8 +290,8 @@ static int damon_reclaim_apply_parameters(void)
>   	if (monitor_region_start > monitor_region_end)
>   		return -EINVAL;
>   	if (!monitor_region_start && !monitor_region_end &&
> -			!get_monitoring_region(&monitor_region_start,
> -				&monitor_region_end))
> +	    !damon_get_sram_monitoring_region(&monitor_region_start,
> +					      &monitor_region_end))
>   		return -EINVAL;
>   	addr_range.start = monitor_region_start;
>   	addr_range.end = monitor_region_end;