[PATCH V4] mm/damon: Remove duplicate get_monitoring_region() definitions

[PATCH V4] mm/damon: Remove duplicate get_monitoring_region() definitions

[Xin Hao]

In lru_sort.c and reclaim.c, they are all defining get_monitoring_region()
function, there is no need to define it separately.

As 'get_monitoring_region()' is not a 'static' function anymore, we try
to use a prefix to distinguish with other functions, so there rename it
to 'damon_find_biggest_system_ram'.

Suggested-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
---
 include/linux/damon.h | 11 +++++++++++
 mm/damon/core.c       | 29 +++++++++++++++++++++++++++++
 mm/damon/lru_sort.c   | 37 ++-----------------------------------
 mm/damon/reclaim.c    | 37 ++-----------------------------------
 4 files changed, 44 insertions(+), 70 deletions(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index 7b1f4a488230..6c863b281fb2 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -448,6 +448,16 @@ struct damon_ctx {
 	struct list_head schemes;
 };
 
+/**
+ * struct damon_system_ram_region - System RAM resource address region of [@start, @end).
+ * @start:	Start address of the  (inclusive).
+ * @end:	End address of the region (exclusive).
+ */
+struct damon_system_ram_region {
+	unsigned long start;
+	unsigned long end;
+};
+
 static inline struct damon_region *damon_next_region(struct damon_region *r)
 {
 	return container_of(r->list.next, struct damon_region, list);
@@ -500,6 +510,7 @@ 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_find_biggest_system_ram(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..d07181e1473b 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -276,6 +276,35 @@ struct damos *damon_new_scheme(
 	return scheme;
 }
 
+static int walk_system_ram(struct resource *res, void *arg)
+{
+	struct damon_system_ram_region *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_find_biggest_system_ram(unsigned long *start, unsigned long *end)
+
+{
+	struct damon_system_ram_region 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..b8ec52739e0f 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_find_biggest_system_ram(&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/reclaim.c b/mm/damon/reclaim.c
index a7faf51b4bd4..7d41913cb0e1 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_find_biggest_system_ram(&monitor_region_start,
+					   &monitor_region_end))
 		return -EINVAL;
 	addr_range.start = monitor_region_start;
 	addr_range.end = monitor_region_end;
-- 
2.31.0

Re: [PATCH V4] mm/damon: Remove duplicate get_monitoring_region() definitions

[SeongJae Park]

On Fri, 9 Sep 2022 10:41:05 +0800 Xin Hao <xhao@linux.alibaba.com> wrote:

> In lru_sort.c and reclaim.c, they are all defining get_monitoring_region()
> function, there is no need to define it separately.
> 
> As 'get_monitoring_region()' is not a 'static' function anymore, we try
> to use a prefix to distinguish with other functions, so there rename it
> to 'damon_find_biggest_system_ram'.
> 
> Suggested-by: SeongJae Park <sj@kernel.org>
> Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
> ---
>  include/linux/damon.h | 11 +++++++++++
>  mm/damon/core.c       | 29 +++++++++++++++++++++++++++++
>  mm/damon/lru_sort.c   | 37 ++-----------------------------------
>  mm/damon/reclaim.c    | 37 ++-----------------------------------
>  4 files changed, 44 insertions(+), 70 deletions(-)
> 
> diff --git a/include/linux/damon.h b/include/linux/damon.h
> index 7b1f4a488230..6c863b281fb2 100644
> --- a/include/linux/damon.h
> +++ b/include/linux/damon.h
> @@ -448,6 +448,16 @@ struct damon_ctx {
>  	struct list_head schemes;
>  };
>  
> +/**
> + * struct damon_system_ram_region - System RAM resource address region of [@start, @end).

I prefer 80 columns, let's break down this line.
https://docs.kernel.org/process/coding-style.html#breaking-long-lines-and-strings

Also this struct is gonna be used by only damon_find_biggest_system_ram(), so I
think it might make more sense to move this into core.c.

And, as this is not aimed to directly be used by external API users, I think it
would make more sense to hide from kernel doc (/* instead of /**).

> + * @start:	Start address of the  (inclusive).

of the 'region'?

> + * @end:	End address of the region (exclusive).

I like the nice explanation: whether its inclusive or exclusive.

> + */
> +struct damon_system_ram_region {
> +	unsigned long start;
> +	unsigned long end;
> +};
> +

As this struct is only used by damon_find_biggest_system_ram(), I think it
might make more sense to move this into core.c?

Below parts all look good.

Also, this patch seems cannot cleanly applied on top of the latest
mm/mm-unstable branch.  Would need rebase.


Thanks,
SJ

[...]

Re: [PATCH V4] mm/damon: Remove duplicate get_monitoring_region() definitions

[SeongJae Park]

As my previous comments are almost only cosmetic trivial nits and I don't want
to make this unnecessarily delayed long, I made the changes on my own and
posted it:
https://lore.kernel.org/damon/20220909213606.136221-1-sj@kernel.org/

Xin, if there was anything I missed or there is anything you disagree about my
changes, please let me know.


Thanks,
SJ

On Fri, 9 Sep 2022 20:45:20 +0000 SeongJae Park <sj@kernel.org> wrote:

> On Fri, 9 Sep 2022 10:41:05 +0800 Xin Hao <xhao@linux.alibaba.com> wrote:
> 
> > In lru_sort.c and reclaim.c, they are all defining get_monitoring_region()
> > function, there is no need to define it separately.
> > 
> > As 'get_monitoring_region()' is not a 'static' function anymore, we try
> > to use a prefix to distinguish with other functions, so there rename it
> > to 'damon_find_biggest_system_ram'.
> > 
> > Suggested-by: SeongJae Park <sj@kernel.org>
> > Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
> > ---
> >  include/linux/damon.h | 11 +++++++++++
> >  mm/damon/core.c       | 29 +++++++++++++++++++++++++++++
> >  mm/damon/lru_sort.c   | 37 ++-----------------------------------
> >  mm/damon/reclaim.c    | 37 ++-----------------------------------
> >  4 files changed, 44 insertions(+), 70 deletions(-)
> > 
> > diff --git a/include/linux/damon.h b/include/linux/damon.h
> > index 7b1f4a488230..6c863b281fb2 100644
> > --- a/include/linux/damon.h
> > +++ b/include/linux/damon.h
> > @@ -448,6 +448,16 @@ struct damon_ctx {
> >  	struct list_head schemes;
> >  };
> >  
> > +/**
> > + * struct damon_system_ram_region - System RAM resource address region of [@start, @end).
> 
> I prefer 80 columns, let's break down this line.
> https://docs.kernel.org/process/coding-style.html#breaking-long-lines-and-strings
> 
> Also this struct is gonna be used by only damon_find_biggest_system_ram(), so I
> think it might make more sense to move this into core.c.
> 
> And, as this is not aimed to directly be used by external API users, I think it
> would make more sense to hide from kernel doc (/* instead of /**).
> 
> > + * @start:	Start address of the  (inclusive).
> 
> of the 'region'?
> 
> > + * @end:	End address of the region (exclusive).
> 
> I like the nice explanation: whether its inclusive or exclusive.
> 
> > + */
> > +struct damon_system_ram_region {
> > +	unsigned long start;
> > +	unsigned long end;
> > +};
> > +
> 
> As this struct is only used by damon_find_biggest_system_ram(), I think it
> might make more sense to move this into core.c?
> 
> Below parts all look good.
> 
> Also, this patch seems cannot cleanly applied on top of the latest
> mm/mm-unstable branch.  Would need rebase.
> 
> 
> Thanks,
> SJ
> 
> [...]
> 

Re: [PATCH V4] mm/damon: Remove duplicate get_monitoring_region() definitions

[haoxin]

在 2022/9/10 上午5:39, SeongJae Park 写道:
> As my previous comments are almost only cosmetic trivial nits and I don't want
> to make this unnecessarily delayed long, I made the changes on my own and
> posted it:
> https://lore.kernel.org/damon/20220909213606.136221-1-sj@kernel.org/
Thanks a lot for your modification，your suggestion is reasonable too.
>
> Xin, if there was anything I missed or there is anything you disagree about my
> changes, please let me know.
>
>
> Thanks,
> SJ
>
> On Fri, 9 Sep 2022 20:45:20 +0000 SeongJae Park <sj@kernel.org> wrote:
>
>> On Fri, 9 Sep 2022 10:41:05 +0800 Xin Hao <xhao@linux.alibaba.com> wrote:
>>
>>> In lru_sort.c and reclaim.c, they are all defining get_monitoring_region()
>>> function, there is no need to define it separately.
>>>
>>> As 'get_monitoring_region()' is not a 'static' function anymore, we try
>>> to use a prefix to distinguish with other functions, so there rename it
>>> to 'damon_find_biggest_system_ram'.
>>>
>>> Suggested-by: SeongJae Park <sj@kernel.org>
>>> Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
>>> ---
>>>   include/linux/damon.h | 11 +++++++++++
>>>   mm/damon/core.c       | 29 +++++++++++++++++++++++++++++
>>>   mm/damon/lru_sort.c   | 37 ++-----------------------------------
>>>   mm/damon/reclaim.c    | 37 ++-----------------------------------
>>>   4 files changed, 44 insertions(+), 70 deletions(-)
>>>
>>> diff --git a/include/linux/damon.h b/include/linux/damon.h
>>> index 7b1f4a488230..6c863b281fb2 100644
>>> --- a/include/linux/damon.h
>>> +++ b/include/linux/damon.h
>>> @@ -448,6 +448,16 @@ struct damon_ctx {
>>>   	struct list_head schemes;
>>>   };
>>>   
>>> +/**
>>> + * struct damon_system_ram_region - System RAM resource address region of [@start, @end).
>> I prefer 80 columns, let's break down this line.
>> https://docs.kernel.org/process/coding-style.html#breaking-long-lines-and-strings
>>
>> Also this struct is gonna be used by only damon_find_biggest_system_ram(), so I
>> think it might make more sense to move this into core.c.
>>
>> And, as this is not aimed to directly be used by external API users, I think it
>> would make more sense to hide from kernel doc (/* instead of /**).
>>
>>> + * @start:	Start address of the  (inclusive).
>> of the 'region'?
>>
>>> + * @end:	End address of the region (exclusive).
>> I like the nice explanation: whether its inclusive or exclusive.
>>
>>> + */
>>> +struct damon_system_ram_region {
>>> +	unsigned long start;
>>> +	unsigned long end;
>>> +};
>>> +
>> As this struct is only used by damon_find_biggest_system_ram(), I think it
>> might make more sense to move this into core.c?
>>
>> Below parts all look good.
>>
>> Also, this patch seems cannot cleanly applied on top of the latest
>> mm/mm-unstable branch.  Would need rebase.
>>
>>
>> Thanks,
>> SJ
>>
>> [...]
>>