[PATCH] x86/resctrl: remove redundant assignment to variable chunks

[PATCH] x86/resctrl: remove redundant assignment to variable chunks

[Colin Ian King]

The variable chunks is being shifted right and re-assinged the shifted
value which is then returned. Since chunks is not being read afterwards
the assignment is redundant and the >>= operator can be replaced with a
shift >> operator instead.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
---
 arch/x86/kernel/cpu/resctrl/monitor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index c9f0f3d63f75..eaf25a234ff5 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -282,7 +282,7 @@ static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr, unsigned int width)
 	u64 shift = 64 - width, chunks;
 
 	chunks = (cur_msr << shift) - (prev_msr << shift);
-	return chunks >>= shift;
+	return chunks >> shift;
 }
 
 static u64 __mon_event_count(u32 rmid, struct rmid_read *rr)
-- 
2.33.1

Re: [PATCH] x86/resctrl: remove redundant assignment to variable chunks

[Fenghua Yu]

On Tue, Dec 07, 2021 at 10:37:35PM +0000, Colin Ian King wrote:
> The variable chunks is being shifted right and re-assinged the shifted
> value which is then returned. Since chunks is not being read afterwards
> the assignment is redundant and the >>= operator can be replaced with a
> shift >> operator instead.
> 
> Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
> ---
>  arch/x86/kernel/cpu/resctrl/monitor.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
> index c9f0f3d63f75..eaf25a234ff5 100644
> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> @@ -282,7 +282,7 @@ static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr, unsigned int width)
>  	u64 shift = 64 - width, chunks;
>  
>  	chunks = (cur_msr << shift) - (prev_msr << shift);
> -	return chunks >>= shift;
> +	return chunks >> shift;
>  }
>  
>  static u64 __mon_event_count(u32 rmid, struct rmid_read *rr)

Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>

Thanks.

-Fenghua

[tip: x86/cache] x86/resctrl: Remove redundant assignment to variable chunks

[tip-bot2 for Colin Ian King]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     df0114f1f8711dbf481324c44cf5a8349130b913
Gitweb:        https://git.kernel.org/tip/df0114f1f8711dbf481324c44cf5a8349130b913
Author:        Colin Ian King <colin.i.king@gmail.com>
AuthorDate:    Tue, 07 Dec 2021 22:37:35 
Committer:     Dave Hansen <dave.hansen@linux.intel.com>
CommitterDate: Thu, 09 Dec 2021 09:57:16 -08:00

x86/resctrl: Remove redundant assignment to variable chunks

The variable chunks is being shifted right and re-assinged the shifted
value which is then returned. Since chunks is not being read afterwards
the assignment is redundant and the >>= operator can be replaced with a
shift >> operator instead.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lkml.kernel.org/r/20211207223735.35173-1-colin.i.king@gmail.com
---
 arch/x86/kernel/cpu/resctrl/monitor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index c9f0f3d..eaf25a2 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -282,7 +282,7 @@ static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr, unsigned int width)
 	u64 shift = 64 - width, chunks;
 
 	chunks = (cur_msr << shift) - (prev_msr << shift);
-	return chunks >>= shift;
+	return chunks >> shift;
 }
 
 static u64 __mon_event_count(u32 rmid, struct rmid_read *rr)