Re: [PATCH v2 3/3] clk: intel: Avoid unnecessary memset by improving code

From: Stephen Boyd
Date: Fri Jul 24 2020 - 04:56:23 EST


Quoting Rahul Tanwar (2020-07-15 23:30:32)
> memset can be avoided in a loop if the variables used are declared
> inside the loop. Move such variables declaration inside the loop
> to avoid memset.
>
> Signed-off-by: Rahul Tanwar <rahul.tanwar@xxxxxxxxxxxxxxx>
> ---
> drivers/clk/x86/clk-cgu.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/clk/x86/clk-cgu.c b/drivers/clk/x86/clk-cgu.c
> index c379fedfb9f2..9a1be7035fd0 100644
> --- a/drivers/clk/x86/clk-cgu.c
> +++ b/drivers/clk/x86/clk-cgu.c
> @@ -581,19 +581,18 @@ int lgm_clk_register_ddiv(struct lgm_clk_provider *ctx,
> unsigned int nr_clk)
> {
> struct device *dev = ctx->dev;
> - struct clk_init_data init = {};
> - struct lgm_clk_ddiv *ddiv;
> struct clk_hw *hw;
> unsigned int idx;
> int ret;
>
> for (idx = 0; idx < nr_clk; idx++, list++) {
> - ddiv = NULL;
> + struct clk_init_data init = {};
> + struct lgm_clk_ddiv *ddiv = NULL;

Assigning to NULL isn't necessary...

> +
> ddiv = devm_kzalloc(dev, sizeof(*ddiv), GFP_KERNEL);

because it's assigned right here. I'll just fix it.

> if (!ddiv)
> return -ENOMEM;
>
> - memset(&init, 0, sizeof(init));
> init.name = list->name;
> init.ops = &lgm_clk_ddiv_ops;
> init.flags = list->flags;