netdev - Re: [Xen-devel] [PATCH net-next V7 3/4] xen-netback: coalesce slots in TX path and fix regressions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20130430154453.GA8728@zion.uk.xensource.com>
Date:	Tue, 30 Apr 2013 16:44:53 +0100
From:	Wei Liu <wei.liu2@...rix.com>
To:	Jan Beulich <JBeulich@...e.com>
CC:	Wei Liu <wei.liu2@...rix.com>,
	Ian Campbell <Ian.Campbell@...rix.com>,
	"davem@...emloft.net" <davem@...emloft.net>,
	"xen-devel@...ts.xen.org" <xen-devel@...ts.xen.org>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [Xen-devel] [PATCH net-next V7 3/4] xen-netback: coalesce slots
 in TX path and fix regressions

On Tue, Apr 30, 2013 at 01:59:59PM +0100, Jan Beulich wrote:
> >>> On 22.04.13 at 14:20, Wei Liu <wei.liu2@...rix.com> wrote:
> > @@ -898,47 +928,78 @@ static void netbk_fatal_tx_err(struct xenvif *vif)
> >  
> >  static int netbk_count_requests(struct xenvif *vif,
> >  				struct xen_netif_tx_request *first,
> > +				RING_IDX first_idx,
> >  				struct xen_netif_tx_request *txp,
> >  				int work_to_do)
> >  {
> >  	RING_IDX cons = vif->tx.req_cons;
> 
> It looks bogus and confusing to me to pass first_idx into this
> function when this really is the same as cons.
> 

So the idea came from David Vrabel and went through two iterations.
Looking at the code he might be mimicking other error handling path up
in the caller, i.e. xen_netbk_tx_build_gops.

It's safe to remove first_idx I think. Just tested replacing first_idx
with cons, everything worked as before.


Wei.

> Jan
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html