RE: [PATCH 2/4 ethtool] ethtool: Support for configurable RSS hash key.

[Venkata Duvvuru <VenkatKumar.Duvvuru@Emulex.Com>]

Ben, Please ignore my previous reply. My reply options were screwed up in that.

> -----Original Message-----
> From: Ben Hutchings [mailto:ben@decadent.org.uk]
> Sent: Monday, January 20, 2014 12:06 AM
> To: Venkata Duvvuru
> Cc: netdev@vger.kernel.org
> Subject: Re: [PATCH 2/4 ethtool] ethtool: Support for configurable RSS hash
> key.
> 
> On Fri, 2014-01-17 at 13:02 +0000, Venkata Duvvuru wrote:
> > This ethtool patch will primarily implement the parser for the options
> provided by the user for set and get hashkey before invoking the ioctl.
> > This patch also has Ethtool man page changes which describes the Usage of
> set and get hashkey options.
> 
> I'd prefer to have this combined with the -x/-X options (and add new long
> options to reflect that they cover the key as well).

if we add hashkey options to the existing -x/-X (--show-rxfh-indir/ --set-rxfh-indir), I think it won't be appropriate going by the command name.
We could change the command name to something like --show-rssconfig /--rss-config but I'm afraid would that be backward compatible?

> 
> [...]
> > diff --git a/ethtool.c b/ethtool.c
> > index b06dfa3..4b05b0c 100644
> > --- a/ethtool.c
> > +++ b/ethtool.c
> > @@ -471,6 +471,59 @@ static int rxflow_str_to_type(const char *str)
> >  	return flow_type;
> >  }
> >
> > +static inline int is_hkey_char_valid(const char rss_hkey_string) {
> 
> A char is not a string.
> 
> > +	/* Are there any invalid characters in the string */
> > +	return ((rss_hkey_string >= '0' && rss_hkey_string <= '9') ||
> > +	       (rss_hkey_string >= 'a' && rss_hkey_string <= 'f') ||
> > +	       (rss_hkey_string >= 'A' && rss_hkey_string <= 'F')); }
> 
> Braces are in the wrong places.  And the whole function is redundant with
> isxdigit() anyway.
> 
> > +static int convert_string_to_hashkey(struct ethtool_rss_hkey *rss_hkey,
> > +				      const char *rss_hkey_string) {
> > +	int i = 0;
> > +	int hex_byte;
> > +
> > +	do {
> > +		if (i > (RSS_HASH_KEY_LEN - 1)) {
> 
> Comparing with the wrong limit.
> 
> [...]
> > +static int get_hashkey(struct cmd_context *ctx) {
> 
> Brace in the wrong place.
> 
> [...]
> > +	for (i = 0; i < RSS_HASH_KEY_LEN; i++) {
> > +		if (i == (RSS_HASH_KEY_LEN - 1))
> 
> Wrong length.
> 
> > +			printf("%02x\n", rss_hkey->data[i]);
> > +		else
> > +			printf("%02x:", rss_hkey->data[i]);
> > +	}
> > +
> > +done:
> > +	free(rss_hkey);
> > +	return rc;
> > +}
> [...]
> 
> --
> Ben Hutchings
> friends: People who know you well, but like you anyway.