* Re: [Outreachy kernel] [PATCH] staging: rtl8712: Add comment to lock declaration
2019-10-07 20:52 [PATCH] staging: rtl8712: Add comment to lock declaration Jules Irenge
@ 2019-10-07 20:55 ` Julia Lawall
2019-10-09 11:18 ` Jules Irenge
2019-10-08 6:16 ` Dan Carpenter
1 sibling, 1 reply; 4+ messages in thread
From: Julia Lawall @ 2019-10-07 20:55 UTC (permalink / raw)
To: Jules Irenge; +Cc: outreachy-kernel, gregkh, Larry.Finger, devel
On Mon, 7 Oct 2019, Jules Irenge wrote:
> Add comment to spinlock declaration to fix warning issued by checkpatch.pl
> "CHECK: spinlock_t definition without comment".
Since it is not apparent from the shown code, it would be helpful to
describe what evidence you used to choose this comment.
thanks,
julia
>
> Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
> ---
> drivers/staging/rtl8712/drv_types.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/rtl8712/drv_types.h b/drivers/staging/rtl8712/drv_types.h
> index 0c4325073c63..960d8709aada 100644
> --- a/drivers/staging/rtl8712/drv_types.h
> +++ b/drivers/staging/rtl8712/drv_types.h
> @@ -160,7 +160,7 @@ struct _adapter {
> int pid; /*process id from UI*/
> struct work_struct wk_filter_rx_ff0;
> u8 blnEnableRxFF0Filter;
> - spinlock_t lock_rx_ff0_filter;
> + spinlock_t lock_rx_ff0_filter; /*spinlock to protect interrupt request*/
> const struct firmware *fw;
> struct usb_interface *pusb_intf;
> struct mutex mutex_start;
> --
> 2.21.0
>
> --
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>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] staging: rtl8712: Add comment to lock declaration
2019-10-07 20:52 [PATCH] staging: rtl8712: Add comment to lock declaration Jules Irenge
2019-10-07 20:55 ` [Outreachy kernel] " Julia Lawall
@ 2019-10-08 6:16 ` Dan Carpenter
1 sibling, 0 replies; 4+ messages in thread
From: Dan Carpenter @ 2019-10-08 6:16 UTC (permalink / raw)
To: Jules Irenge; +Cc: outreachy-kernel, devel, gregkh, Larry.Finger
On Mon, Oct 07, 2019 at 09:52:48PM +0100, Jules Irenge wrote:
> Add comment to spinlock declaration to fix warning issued by checkpatch.pl
> "CHECK: spinlock_t definition without comment".
>
> Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
> ---
> drivers/staging/rtl8712/drv_types.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/rtl8712/drv_types.h b/drivers/staging/rtl8712/drv_types.h
> index 0c4325073c63..960d8709aada 100644
> --- a/drivers/staging/rtl8712/drv_types.h
> +++ b/drivers/staging/rtl8712/drv_types.h
> @@ -160,7 +160,7 @@ struct _adapter {
> int pid; /*process id from UI*/
> struct work_struct wk_filter_rx_ff0;
> u8 blnEnableRxFF0Filter;
> - spinlock_t lock_rx_ff0_filter;
> + spinlock_t lock_rx_ff0_filter; /*spinlock to protect interrupt request*/
This spinlock seems to be nonsense. It's only used one time:
drivers/staging/rtl8712/xmit_linux.c
94 void r8712_SetFilter(struct work_struct *work)
95 {
96 struct _adapter *adapter = container_of(work, struct _adapter,
97 wk_filter_rx_ff0);
98 u8 oldvalue = 0x00, newvalue = 0x00;
99 unsigned long irqL;
100
101 oldvalue = r8712_read8(adapter, 0x117);
102 newvalue = oldvalue & 0xfe;
103 r8712_write8(adapter, 0x117, newvalue);
104
105 spin_lock_irqsave(&adapter->lock_rx_ff0_filter, irqL);
106 adapter->blnEnableRxFF0Filter = 1;
It only protects writing to ->blnEnableRxFF0Filter but it doesn't
protect reading so it can't possibly work.
107 spin_unlock_irqrestore(&adapter->lock_rx_ff0_filter, irqL);
108 do {
109 msleep(100);
110 } while (adapter->blnEnableRxFF0Filter == 1);
111 r8712_write8(adapter, 0x117, oldvalue);
112 }
Also put a space after /* and before */ so the comment looks like:
/* spinlock to protect interrupt request */
But in this case, the comment isn't correct so please just leave it
as-is until someone can fix the locking.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 4+ messages in thread