Re: [PATCH v9 REBASE 6/9] USB: notify phy when root hub port connect change

[Greg KH <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>]

On Sat, Jul 07, 2012 at 10:56:45PM +0800, Richard Zhao wrote:
> Phy may need to change settings when port connect change.
> 
> Signed-off-by: Richard Zhao <richard.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
> Tested-by: Subodh Nijsure <snijsure-4jo+YWezP1RWk0Htik3J/w@public.gmane.org>
> ---
>  drivers/usb/core/hub.c |    8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 4cc8dc9..2ba9d84 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -20,6 +20,7 @@
>  #include <linux/usb.h>
>  #include <linux/usbdevice_fs.h>
>  #include <linux/usb/hcd.h>
> +#include <linux/usb/otg.h>
>  #include <linux/usb/quirks.h>
>  #include <linux/kthread.h>
>  #include <linux/mutex.h>
> @@ -4037,6 +4038,13 @@ static void hub_port_connect_change(struct usb_hub *hub, int port1,
>  		}
>  	}
>  
> +	if (unlikely(hcd->phy && !hdev->parent)) {

Why is this "unlikely"?  And why mark it as such, is this a "fast path"
that needs the compiler to know this hint to optimize things here?

Please don't use likely() or unlikely() except in places it really is
needed, _and_ you have measured the difference.  Have you done so in
this place?

thanks,

greg k-h
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