Re: [PATCH v3 -next] staging: vc04_services: use DEFINE_MUTEX() for mutex lock

From: Greg KH
Date: Tue Jan 05 2021 - 01:03:31 EST


On Tue, Jan 05, 2021 at 10:05:47AM +0800, Zheng Yongjun wrote:
> mutex lock can be initialized automatically with DEFINE_MUTEX()
> rather than explicitly calling mutex_init().
>
> Signed-off-by: Zheng Yongjun <zhengyongjun3@xxxxxxxxxx>
> ---
> .../vc04_services/interface/vchiq_arm/vchiq_connected.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_connected.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_connected.c
> index 79b75efa6868..938307f39b9c 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_connected.c
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_connected.c
> @@ -12,15 +12,13 @@ static int g_connected;
> static int g_num_deferred_callbacks;
> static VCHIQ_CONNECTED_CALLBACK_T g_deferred_callback[MAX_CALLBACKS];
> static int g_once_init;
> -static struct mutex g_connected_mutex;
> +static DEFINE_MUTEX(g_connected_mutex);
>
> /* Function to initialize our lock */
> static void connected_init(void)
> {
> - if (!g_once_init) {
> - mutex_init(&g_connected_mutex);
> + if (!g_once_init)
> g_once_init = 1;
> - }

Why do you still need g_once_init now?