Re: [Linuxptp-users] Fw: “Resource temporarily unavailable” errors during flood ping test

[Richard C. <ric...@gm...>]

On Tue, Oct 30, 2012 at 04:47:09PM +0100, Mario Molitor wrote:
>  
> I have instrument the ptp4l code and I could see that a part of problem was a not correct error handling in the function sk_receive(). The recvmsg() returns sometime a EAGAIN and try-again variable was not increment.
> I have changed this and now disappears this error message with GM Clock search during my flood ping test and it works all very well. 
>  
>  My code changes:
>  --- a/sk.c	
>  +++ b/sk.c	
>  
>   		}
>   		if (errno == EINTR) {
>   			try_again++;
>  -		} else if (errno == EAGAIN) {
>  +		} else if ((errno == EAGAIN ) || (errno == EWOULDBLOCK)) {

This does not accomplish anything since:

--- /usr/include/asm-generic/errno.h ---

#define	  EWOULDBLOCK	 EAGAIN	  /* Operation would block */


>   			usleep(1);
>  +			try_again++;

This is the wrong solution. The right way is to set the
tx_timestamp_retries configuration variable to a higher number, like
200 or 2000 instead of the default of 2.

HTH,
Richard