Re: [PATCH] LMK: Optimize lowmem_shrink

[Colin Cross]

On Mon, Aug 19, 2013 at 7:23 PM, Colin Cross <ccross@xxxxxxxxxxx> wrote:
> On Mon, Aug 19, 2013 at 6:16 PM, Leon Ma <xindong.ma@xxxxxxxxx> wrote:
>> From: Leon Ma <xindong.ma@xxxxxxxxx>
>> Date: Mon, 19 Aug 2013 14:22:38 +0800
>> Subject: [PATCH] LMK: Optimize lowmem_shrink.
>>
>> By comparing with selected_oom_score_adj instead of min_score_adj,
>> we may do less calculation.
>>
>> Signed-off-by: Leon Ma <xindong.ma@xxxxxxxxx>
>> ---
>>  drivers/staging/android/lowmemorykiller.c |   12 ++++--------
>>  1 files changed, 4 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/staging/android/lowmemorykiller.c
>> b/drivers/staging/android/lowmemorykiller.c
>> index f6c05c9..cb944c5 100644
>> --- a/drivers/staging/android/lowmemorykiller.c
>> +++ b/drivers/staging/android/lowmemorykiller.c
>> @@ -126,7 +126,7 @@ static int lowmem_shrink(struct shrinker *s, struct
>> shrink_control *sc)
>>                         return 0;
>>                 }
>>                 oom_score_adj = p->signal->oom_score_adj;
>> -               if (oom_score_adj < min_score_adj) {
>> +               if (oom_score_adj < selected_oom_score_adj) {
>
> This needs to be oom_score_adj <= selected_oom_score_adj.

Sorry, got the logic inverted, yours is correct.

>>                         task_unlock(p);
>>                         continue;
>>                 }
>> @@ -134,13 +134,9 @@ static int lowmem_shrink(struct shrinker *s, struct
>> shrink_control *sc)
>>                 task_unlock(p);
>>                 if (tasksize <= 0)
>>                         continue;
>> -               if (selected) {
>> -                       if (oom_score_adj < selected_oom_score_adj)
>> -                               continue;
>> -                       if (oom_score_adj == selected_oom_score_adj &&
>> -                           tasksize <= selected_tasksize)
>> -                               continue;
>> -               }
>> +               if (selected && oom_score_adj == selected_oom_score_adj &&
>> +                       tasksize <= selected_tasksize)
>> +                       continue;
>>                 selected = p;
>>                 selected_tasksize = tasksize;
>>                 selected_oom_score_adj = oom_score_adj;
>> --
>> 1.7.4.1
>>
>>
>>
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