2020-04-21 21:41:15

by Wei Yang

Subject: [Patch v2 1/3] mm/swapfile.c: found_free could be represented by (tmp < max)

This is not necessary to use the variable found_free to record the
status. Just check tmp and max is enough.

Signed-off-by: Wei Yang <[email protected]>
---
mm/swapfile.c | 11 +++--------
1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 469ab417ed43..d203cdc6750a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -601,7 +601,6 @@ static bool scan_swap_map_try_ssd_cluster(struct swap_info_struct *si,
{
struct percpu_cluster *cluster;
struct swap_cluster_info *ci;
- bool found_free;
unsigned long tmp, max;

new_cluster:
@@ -623,8 +622,6 @@ static bool scan_swap_map_try_ssd_cluster(struct swap_info_struct *si,
return false;
}

- found_free = false;
-
/*
* Other CPUs can use our cluster if they can't find a free cluster,
* check if there is still free entry in the cluster
@@ -638,21 +635,19 @@ static bool scan_swap_map_try_ssd_cluster(struct swap_info_struct *si,
}
ci = lock_cluster(si, tmp);
while (tmp < max) {
- if (!si->swap_map[tmp]) {
- found_free = true;
+ if (!si->swap_map[tmp])
break;
- }
tmp++;
}
unlock_cluster(ci);
- if (!found_free) {
+ if (tmp >= max) {
cluster_set_null(&cluster->index);
goto new_cluster;
}
cluster->next = tmp + 1;
*offset = tmp;
*scan_base = tmp;
- return found_free;
+ return tmp < max;
}

static void __del_from_avail_list(struct swap_info_struct *p)
--
2.23.0

2020-04-22 00:37:54

by Huang, Ying

Subject: Re: [Patch v2 1/3] mm/swapfile.c: found_free could be represented by (tmp < max)

Wei Yang <[email protected]> writes:

> This is not necessary to use the variable found_free to record the
> status. Just check tmp and max is enough.
>
> Signed-off-by: Wei Yang <[email protected]>

All 3 patches looks good to me. Thanks!

Reviewed-by: "Huang, Ying" <[email protected]>

Best Regards,
Huang, Ying

> ---
> mm/swapfile.c | 11 +++--------
> 1 file changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/mm/swapfile.c b/mm/swapfile.c
> index 469ab417ed43..d203cdc6750a 100644
> --- a/mm/swapfile.c
> +++ b/mm/swapfile.c
> @@ -601,7 +601,6 @@ static bool scan_swap_map_try_ssd_cluster(struct swap_info_struct *si,
> {
> struct percpu_cluster *cluster;
> struct swap_cluster_info *ci;
> - bool found_free;
> unsigned long tmp, max;
>
> new_cluster:
> @@ -623,8 +622,6 @@ static bool scan_swap_map_try_ssd_cluster(struct swap_info_struct *si,
> return false;
> }
>
> - found_free = false;
> -
> /*
> * Other CPUs can use our cluster if they can't find a free cluster,
> * check if there is still free entry in the cluster
> @@ -638,21 +635,19 @@ static bool scan_swap_map_try_ssd_cluster(struct swap_info_struct *si,
> }
> ci = lock_cluster(si, tmp);
> while (tmp < max) {
> - if (!si->swap_map[tmp]) {
> - found_free = true;
> + if (!si->swap_map[tmp])
> break;
> - }
> tmp++;
> }
> unlock_cluster(ci);
> - if (!found_free) {
> + if (tmp >= max) {
> cluster_set_null(&cluster->index);
> goto new_cluster;
> }
> cluster->next = tmp + 1;
> *offset = tmp;
> *scan_base = tmp;
> - return found_free;
> + return tmp < max;
> }
>
> static void __del_from_avail_list(struct swap_info_struct *p)