[PATCH v2] fs/pstore: Optimization function ramoops_init_przs

[PATCH v2] fs/pstore: Optimization function ramoops_init_przs

[Wang Long]

The value of cxt->record_size does not change in the loop,
so this patch optimize the assign statement by dropping
sz entirely and using cxt->record_size in its place.

Signed-off-by: Wang Long <long.wanglong@huawei.com>
---
 fs/pstore/ram.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 44a549b..f29373d 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -394,18 +394,16 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
 	}
 
 	for (i = 0; i < cxt->max_dump_cnt; i++) {
-		size_t sz = cxt->record_size;
-
-		cxt->przs[i] = persistent_ram_new(*paddr, sz, 0,
+		cxt->przs[i] = persistent_ram_new(*paddr, cxt->record_size, 0,
 						  &cxt->ecc_info,
 						  cxt->memtype);
 		if (IS_ERR(cxt->przs[i])) {
 			err = PTR_ERR(cxt->przs[i]);
 			dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
-				sz, (unsigned long long)*paddr, err);
+				cxt->record_size, (unsigned long long)*paddr, err);
 			goto fail_prz;
 		}
-		*paddr += sz;
+		*paddr += cxt->record_size;
 	}
 
 	return 0;
-- 
1.8.3.4

Re: [PATCH v2] fs/pstore: Optimization function ramoops_init_przs

[Kees Cook]

On Tue, Mar 17, 2015 at 6:41 PM, Wang Long <long.wanglong@huawei.com> wrote:
> The value of cxt->record_size does not change in the loop,
> so this patch optimize the assign statement by dropping
> sz entirely and using cxt->record_size in its place.
>
> Signed-off-by: Wang Long <long.wanglong@huawei.com>

Thanks!

Acked-by: Kees Cook <keescook@chromium.org>

-Kees

> ---
>  fs/pstore/ram.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
> index 44a549b..f29373d 100644
> --- a/fs/pstore/ram.c
> +++ b/fs/pstore/ram.c
> @@ -394,18 +394,16 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
>         }
>
>         for (i = 0; i < cxt->max_dump_cnt; i++) {
> -               size_t sz = cxt->record_size;
> -
> -               cxt->przs[i] = persistent_ram_new(*paddr, sz, 0,
> +               cxt->przs[i] = persistent_ram_new(*paddr, cxt->record_size, 0,
>                                                   &cxt->ecc_info,
>                                                   cxt->memtype);
>                 if (IS_ERR(cxt->przs[i])) {
>                         err = PTR_ERR(cxt->przs[i]);
>                         dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
> -                               sz, (unsigned long long)*paddr, err);
> +                               cxt->record_size, (unsigned long long)*paddr, err);
>                         goto fail_prz;
>                 }
> -               *paddr += sz;
> +               *paddr += cxt->record_size;
>         }
>
>         return 0;
> --
> 1.8.3.4
>
> --
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-- 
Kees Cook
Chrome OS Security

Re: [PATCH v2] fs/pstore: Optimization function ramoops_init_przs

[long.wanglong]

On 2015/3/19 4:11, Kees Cook wrote:
> On Tue, Mar 17, 2015 at 6:41 PM, Wang Long <long.wanglong@huawei.com> wrote:
>> The value of cxt->record_size does not change in the loop,
>> so this patch optimize the assign statement by dropping
>> sz entirely and using cxt->record_size in its place.
>>
>> Signed-off-by: Wang Long <long.wanglong@huawei.com>
> 
> Thanks!
> 
> Acked-by: Kees Cook <keescook@chromium.org>
> 
> -Kees
> 
>> ---
>>  fs/pstore/ram.c | 8 +++-----
>>  1 file changed, 3 insertions(+), 5 deletions(-)
>>
>> diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
>> index 44a549b..f29373d 100644
>> --- a/fs/pstore/ram.c
>> +++ b/fs/pstore/ram.c
>> @@ -394,18 +394,16 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
>>         }
>>
>>         for (i = 0; i < cxt->max_dump_cnt; i++) {
>> -               size_t sz = cxt->record_size;
>> -
>> -               cxt->przs[i] = persistent_ram_new(*paddr, sz, 0,
>> +               cxt->przs[i] = persistent_ram_new(*paddr, cxt->record_size, 0,
>>                                                   &cxt->ecc_info,
>>                                                   cxt->memtype);
>>                 if (IS_ERR(cxt->przs[i])) {
>>                         err = PTR_ERR(cxt->przs[i]);
>>                         dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
>> -                               sz, (unsigned long long)*paddr, err);
>> +                               cxt->record_size, (unsigned long long)*paddr, err);
>>                         goto fail_prz;
>>                 }
>> -               *paddr += sz;
>> +               *paddr += cxt->record_size;
>>         }
>>
>>         return 0;
>> --
>> 1.8.3.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
> 
> 
> 

Hi Tony Luck,

Could you please help to commit this patch?

Thank you.

Best Regards
Wang Long