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SubjectRe: First kernel patch (optimization)
On Tue, Sep 15, 2015 at 08:53:28PM +0100, Eric Curtin wrote:
> My first kernel patch, hope I did everything correctly! Instead of calling strlen on every iteration of the for loop, just call it once instead and store in a variable.

this should be broken up at 72 characters. Also, your subject and commit
log make no sense from a project history perspective. You don't need to
mention it's your first patch, just go straight to the details.

For the subject, I'd use something like:

tools: usbip: detach: avoid calling strlen() at each iteration

and for the commit log:

Instead of calling strlen() on every iterations of the for loop,
just call it once and cache the result in a temporary local variable
which will be used in the for loop instead.

cheers

> Signed-off-by: Eric Curtin <ericcurtin17@gmail.com>
>
> diff --git a/tools/usb/usbip/src/usbip_detach.c b/tools/usb/usbip/src/usbip_detach.c
> index 05c6d15..9db9d21 100644
> --- a/tools/usb/usbip/src/usbip_detach.c
> +++ b/tools/usb/usbip/src/usbip_detach.c
> @@ -47,7 +47,9 @@ static int detach_port(char *port)
> uint8_t portnum;
> char path[PATH_MAX+1];
>
> - for (unsigned int i = 0; i < strlen(port); i++)
> + unsigned int port_len = strlen(port);
> +
> + for (unsigned int i = 0; i < port_len; i++)
> if (!isdigit(port[i])) {
> err("invalid port %s", port);
> return -1;
>
> --
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--
balbi
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