[PATCH] crypto: xor - Remove unused variable count in do_xor_speed

[PATCH] crypto: xor - Remove unused variable count in do_xor_speed

[Nathan Chancellor]

Clang warns:

crypto/xor.c:101:4: warning: variable 'count' is uninitialized when used
here [-Wuninitialized]
                        count++;
                        ^~~~~
crypto/xor.c:86:17: note: initialize the variable 'count' to silence
this warning
        int i, j, count;
                       ^
                        = 0
1 warning generated.

After the refactoring to use ktime that happened in this function, count
is only assigned, never read. Just remove the variable to get rid of the
warning.

Fixes: c055e3eae0f1 ("crypto: xor - use ktime for template benchmarking")
Link: https://github.com/ClangBuiltLinux/linux/issues/1171
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---
 crypto/xor.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/crypto/xor.c b/crypto/xor.c
index a0badbc03577..eacbf4f93990 100644
--- a/crypto/xor.c
+++ b/crypto/xor.c
@@ -83,7 +83,7 @@ static void __init
 do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
 {
 	int speed;
-	int i, j, count;
+	int i, j;
 	ktime_t min, start, diff;
 
 	tmpl->next = template_list;
@@ -98,8 +98,6 @@ do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
 			mb(); /* prevent loop optimzation */
 			tmpl->do_2(BENCH_SIZE, b1, b2);
 			mb();
-			count++;
-			mb();
 		}
 		diff = ktime_sub(ktime_get(), start);
 		if (diff < min)

base-commit: ed4424f2fb02497b0ea92bf58c533c598c0da1d3
-- 
2.29.0.rc0

Re: [PATCH] crypto: xor - Remove unused variable count in do_xor_speed

[Doug Anderson]

Hi,

On Tue, Oct 6, 2020 at 12:59 PM Nathan Chancellor
<natechancellor@gmail.com> wrote:
>
> Clang warns:
>
> crypto/xor.c:101:4: warning: variable 'count' is uninitialized when used
> here [-Wuninitialized]
>                         count++;
>                         ^~~~~
> crypto/xor.c:86:17: note: initialize the variable 'count' to silence
> this warning
>         int i, j, count;
>                        ^
>                         = 0
> 1 warning generated.
>
> After the refactoring to use ktime that happened in this function, count
> is only assigned, never read. Just remove the variable to get rid of the
> warning.
>
> Fixes: c055e3eae0f1 ("crypto: xor - use ktime for template benchmarking")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1171
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
>  crypto/xor.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)

Whoops!  Sorry for missing this in my review.

Reviewed-by: Douglas Anderson <dianders@chromium.org>

Re: [PATCH] crypto: xor - Remove unused variable count in do_xor_speed

[Ard Biesheuvel]

On Tue, 6 Oct 2020 at 21:59, Nathan Chancellor <natechancellor@gmail.com> wrote:
>
> Clang warns:
>
> crypto/xor.c:101:4: warning: variable 'count' is uninitialized when used
> here [-Wuninitialized]
>                         count++;
>                         ^~~~~
> crypto/xor.c:86:17: note: initialize the variable 'count' to silence
> this warning
>         int i, j, count;
>                        ^
>                         = 0
> 1 warning generated.
>
> After the refactoring to use ktime that happened in this function, count
> is only assigned, never read. Just remove the variable to get rid of the
> warning.
>
> Fixes: c055e3eae0f1 ("crypto: xor - use ktime for template benchmarking")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1171
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Acked-by: Ard Biesheuvel <ardb@kernel.org>

> ---
>  crypto/xor.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/crypto/xor.c b/crypto/xor.c
> index a0badbc03577..eacbf4f93990 100644
> --- a/crypto/xor.c
> +++ b/crypto/xor.c
> @@ -83,7 +83,7 @@ static void __init
>  do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
>  {
>         int speed;
> -       int i, j, count;
> +       int i, j;
>         ktime_t min, start, diff;
>
>         tmpl->next = template_list;
> @@ -98,8 +98,6 @@ do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
>                         mb(); /* prevent loop optimzation */
>                         tmpl->do_2(BENCH_SIZE, b1, b2);
>                         mb();
> -                       count++;
> -                       mb();
>                 }
>                 diff = ktime_sub(ktime_get(), start);
>                 if (diff < min)
>
> base-commit: ed4424f2fb02497b0ea92bf58c533c598c0da1d3
> --
> 2.29.0.rc0
>

Re: [PATCH] crypto: xor - Remove unused variable count in do_xor_speed

[Herbert Xu]

On Tue, Oct 06, 2020 at 12:58:48PM -0700, Nathan Chancellor wrote:
> Clang warns:
> 
> crypto/xor.c:101:4: warning: variable 'count' is uninitialized when used
> here [-Wuninitialized]
>                         count++;
>                         ^~~~~
> crypto/xor.c:86:17: note: initialize the variable 'count' to silence
> this warning
>         int i, j, count;
>                        ^
>                         = 0
> 1 warning generated.
> 
> After the refactoring to use ktime that happened in this function, count
> is only assigned, never read. Just remove the variable to get rid of the
> warning.
> 
> Fixes: c055e3eae0f1 ("crypto: xor - use ktime for template benchmarking")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1171
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
>  crypto/xor.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt