2019-01-23 08:39:42

by Yue Haibing

Subject: [PATCH -next] usb: host: drop pointless static qualifier

There is no need to have the 'dummy_mask' variable static since new
value always be assigned before use it.

Signed-off-by: YueHaibing <[email protected]>
---
drivers/usb/host/ehci-ps3.c | 2 +-
drivers/usb/host/ohci-ps3.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/ehci-ps3.c b/drivers/usb/host/ehci-ps3.c
index 454d8c6..91cee02 100644
--- a/drivers/usb/host/ehci-ps3.c
+++ b/drivers/usb/host/ehci-ps3.c
@@ -86,7 +86,7 @@ static int ps3_ehci_probe(struct ps3_system_bus_device *dev)
int result;
struct usb_hcd *hcd;
unsigned int virq;
- static u64 dummy_mask;
+ u64 dummy_mask;

if (usb_disabled()) {
result = -ENODEV;
diff --git a/drivers/usb/host/ohci-ps3.c b/drivers/usb/host/ohci-ps3.c
index 395f9d3..a1c1bdf 100644
--- a/drivers/usb/host/ohci-ps3.c
+++ b/drivers/usb/host/ohci-ps3.c
@@ -69,7 +69,7 @@ static int ps3_ohci_probe(struct ps3_system_bus_device *dev)
int result;
struct usb_hcd *hcd;
unsigned int virq;
- static u64 dummy_mask;
+ u64 dummy_mask;

if (usb_disabled()) {
result = -ENODEV;
--
2.7.0

2019-01-23 16:11:04

by Alan Stern

Subject: Re: [PATCH -next] usb: host: drop pointless static qualifier

On Wed, 23 Jan 2019, YueHaibing wrote:

> There is no need to have the 'dummy_mask' variable static since new
> value always be assigned before use it.
>
> Signed-off-by: YueHaibing <[email protected]>
> ---
> drivers/usb/host/ehci-ps3.c | 2 +-
> drivers/usb/host/ohci-ps3.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/host/ehci-ps3.c b/drivers/usb/host/ehci-ps3.c
> index 454d8c6..91cee02 100644
> --- a/drivers/usb/host/ehci-ps3.c
> +++ b/drivers/usb/host/ehci-ps3.c
> @@ -86,7 +86,7 @@ static int ps3_ehci_probe(struct ps3_system_bus_device *dev)
> int result;
> struct usb_hcd *hcd;
> unsigned int virq;
> - static u64 dummy_mask;
> + u64 dummy_mask;
>
> if (usb_disabled()) {
> result = -ENODEV;
> diff --git a/drivers/usb/host/ohci-ps3.c b/drivers/usb/host/ohci-ps3.c
> index 395f9d3..a1c1bdf 100644
> --- a/drivers/usb/host/ohci-ps3.c
> +++ b/drivers/usb/host/ohci-ps3.c
> @@ -69,7 +69,7 @@ static int ps3_ohci_probe(struct ps3_system_bus_device *dev)
> int result;
> struct usb_hcd *hcd;
> unsigned int virq;
> - static u64 dummy_mask;
> + u64 dummy_mask;
>
> if (usb_disabled()) {
> result = -ENODEV;

No. You need to read the code and understand how a variable is used
before you decide to modify it.

In this case, a suitable approach would be to change the declaration
so that it says:

status u64 dummy_mask = DMA_BIT_MASK(32);

and remove the line that does the assignment dynamically.

Alan Stern

2019-01-24 03:15:01

by Yue Haibing

Subject: Re: [PATCH -next] usb: host: drop pointless static qualifier

On 2019/1/24 0:09, Alan Stern wrote:
> On Wed, 23 Jan 2019, YueHaibing wrote:
>
>> There is no need to have the 'dummy_mask' variable static since new
>> value always be assigned before use it.
>>
>> Signed-off-by: YueHaibing <[email protected]>
>> ---
>> drivers/usb/host/ehci-ps3.c | 2 +-
>> drivers/usb/host/ohci-ps3.c | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/host/ehci-ps3.c b/drivers/usb/host/ehci-ps3.c
>> index 454d8c6..91cee02 100644
>> --- a/drivers/usb/host/ehci-ps3.c
>> +++ b/drivers/usb/host/ehci-ps3.c
>> @@ -86,7 +86,7 @@ static int ps3_ehci_probe(struct ps3_system_bus_device *dev)
>> int result;
>> struct usb_hcd *hcd;
>> unsigned int virq;
>> - static u64 dummy_mask;
>> + u64 dummy_mask;
>>
>> if (usb_disabled()) {
>> result = -ENODEV;
>> diff --git a/drivers/usb/host/ohci-ps3.c b/drivers/usb/host/ohci-ps3.c
>> index 395f9d3..a1c1bdf 100644
>> --- a/drivers/usb/host/ohci-ps3.c
>> +++ b/drivers/usb/host/ohci-ps3.c
>> @@ -69,7 +69,7 @@ static int ps3_ohci_probe(struct ps3_system_bus_device *dev)
>> int result;
>> struct usb_hcd *hcd;
>> unsigned int virq;
>> - static u64 dummy_mask;
>> + u64 dummy_mask;
>>
>> if (usb_disabled()) {
>> result = -ENODEV;
>
> No. You need to read the code and understand how a variable is used
> before you decide to modify it.

Sorry, I misread the code, so just leave it as is.

>
> In this case, a suitable approach would be to change the declaration
> so that it says:
>
> status u64 dummy_mask = DMA_BIT_MASK(32);
>
> and remove the line that does the assignment dynamically.
>
> Alan Stern
>
>
> .
>