Re: [PATCH 1/1] IOMMU-MSM: Deletion of unnecessary checks before the function call "clk_disable"

Re: [PATCH 1/1] IOMMU-MSM: Deletion of unnecessary checks before the function call "clk_disable"

[SF Markus Elfring]

>> If you are convinced that dropping the null tests is a good idea, then you 
>> can submit the patch that makes the change to the relevant maintainers and 
>> mailing lists.

>From af73fb59d5d4b2c2890000fb236d0752522b6b38 Mon Sep 17 00:00:00 2001
From: Markus Elfring <elfring@users.sourceforge.net>
Date: Wed, 22 Oct 2014 19:39:21 +0200
Subject: [PATCH] IOMMU-MSM: Deletion of unnecessary checks before the function
 call "clk_disable"

A semantic patch approach was proposed with the subject "[PATCH with
Coccinelle?] Deletion of unnecessary checks before specific function calls"
on 2014-03-05.
https://lkml.org/lkml/2014/3/5/344
http://article.gmane.org/gmane.comp.version-control.coccinelle/3513/

This patch pattern application was repeated with the help of the software
"Coccinelle 1.0.0-rc22" on the source files for Linux 3.17.1. An extract
of the automatically generated update suggestions is shown here.

It was determined that the affected source code places call functions
which perform input parameter validation already. It is therefore not
needed that a similar safety check is repeated at the call site.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
 drivers/iommu/msm_iommu.c     | 3 +--
 drivers/iommu/msm_iommu_dev.c | 6 ++----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index 6e3dcc28..3e4d888 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -73,8 +73,7 @@ fail:

 static void __disable_clocks(struct msm_iommu_drvdata *drvdata)
 {
-	if (drvdata->clk)
-		clk_disable(drvdata->clk);
+	clk_disable(drvdata->clk);
 	clk_disable(drvdata->pclk);
 }

diff --git a/drivers/iommu/msm_iommu_dev.c b/drivers/iommu/msm_iommu_dev.c
index 61def7cb..9574d21 100644
--- a/drivers/iommu/msm_iommu_dev.c
+++ b/drivers/iommu/msm_iommu_dev.c
@@ -224,8 +224,7 @@ static int msm_iommu_probe(struct platform_device *pdev)

 	platform_set_drvdata(pdev, drvdata);

-	if (iommu_clk)
-		clk_disable(iommu_clk);
+	clk_disable(iommu_clk);

 	clk_disable(iommu_pclk);

@@ -323,8 +322,7 @@ static int msm_iommu_ctx_probe(struct platform_device *pdev)
 		SET_NSCFG(drvdata->base, mid, 3);
 	}

-	if (drvdata->clk)
-		clk_disable(drvdata->clk);
+	clk_disable(drvdata->clk);
 	clk_disable(drvdata->pclk);

 	dev_info(&pdev->dev, "context %s using bank %d\n", c->name, c->num);
-- 
2.1.2

Re: [PATCH 1/1] IOMMU-MSM: Deletion of unnecessary checks before the function call "clk_disable"

[Jörg Rödel]

On Wed, Oct 22, 2014 at 08:00:17PM +0200, SF Markus Elfring wrote:
>  drivers/iommu/msm_iommu.c     | 3 +--
>  drivers/iommu/msm_iommu_dev.c | 6 ++----
>  2 files changed, 3 insertions(+), 6 deletions(-)

Applied to arm/msm, thanks.

[PATCH] iommu/arm-smmu: Delete an unnecessary check before the function call "free_io_pgtable_ops"

[SF Markus Elfring]

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Sun, 28 Jun 2015 15:55:11 +0200

The free_io_pgtable_ops() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
 drivers/iommu/arm-smmu-v3.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index f141301..8e9ec81 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -1389,8 +1389,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 
-	if (smmu_domain->pgtbl_ops)
-		free_io_pgtable_ops(smmu_domain->pgtbl_ops);
+	free_io_pgtable_ops(smmu_domain->pgtbl_ops);
 
 	/* Free the CD and ASID, if we allocated them */
 	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-- 
2.4.4

[PATCH] iommu/arm-smmu: Delete an unnecessary check before free_io_pgtable_ops()

[SF Markus Elfring]

From: Markus Elfring <elfring-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
Date: Fri, 6 Nov 2015 18:32:41 +0100

The free_io_pgtable_ops() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
---
 drivers/iommu/arm-smmu.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 47dc7a7..1ce4b85 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -945,9 +945,7 @@ static void arm_smmu_destroy_domain_context(struct iommu_domain *domain)
 		free_irq(irq, domain);
 	}
 
-	if (smmu_domain->pgtbl_ops)
-		free_io_pgtable_ops(smmu_domain->pgtbl_ops);
-
+	free_io_pgtable_ops(smmu_domain->pgtbl_ops);
 	__arm_smmu_free_bitmap(smmu->context_map, cfg->cbndx);
 }
 
-- 
2.6.2

[PATCH] IOMMU-Tegra: gart: Delete an unnecessary check before the function call "vfree"

[SF Markus Elfring]

From: Markus Elfring <elfring-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
Date: Thu, 5 Feb 2015 17:54:16 +0100

The vfree() function performs also input parameter validation.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
---
 drivers/iommu/tegra-gart.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index f722a0c..07a795a 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -404,8 +404,7 @@ static int tegra_gart_remove(struct platform_device *pdev)
 	struct gart_device *gart = platform_get_drvdata(pdev);
 
 	writel(0, gart->regs + GART_CONFIG);
-	if (gart->savedata)
-		vfree(gart->savedata);
+	vfree(gart->savedata);
 	gart_handle = NULL;
 	return 0;
 }
-- 
2.2.2

Re: [PATCH] IOMMU-Tegra: gart: Delete an unnecessary check before the function call "vfree"

[SF Markus Elfring]

> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Thu, 5 Feb 2015 17:54:16 +0100
> 
> The vfree() function performs also input parameter validation.
> Thus the test around the call is not needed.
> 
> This issue was detected by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
>  drivers/iommu/tegra-gart.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
> index f722a0c..07a795a 100644
> --- a/drivers/iommu/tegra-gart.c
> +++ b/drivers/iommu/tegra-gart.c
> @@ -404,8 +404,7 @@ static int tegra_gart_remove(struct platform_device *pdev)
>  	struct gart_device *gart = platform_get_drvdata(pdev);
>  
>  	writel(0, gart->regs + GART_CONFIG);
> -	if (gart->savedata)
> -		vfree(gart->savedata);
> +	vfree(gart->savedata);
>  	gart_handle = NULL;
>  	return 0;
>  }
> 

Would you like to integrate this update suggestion
into another source code repository?

Regards,
Markus