linux-kernel - Re: [RFC][PATCH 2/4] tracing: add rb_event

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <1237356725.7922.16.camel@charm-linux>
Date:	Wed, 18 Mar 2009 01:12:05 -0500
From:	Tom Zanussi <tzanussi@...il.com>
To:	Steven Rostedt <rostedt@...dmis.org>
Cc:	linux-kernel <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...e.hu>,
	Frédéric Weisbecker <fweisbec@...il.com>
Subject: Re: [RFC][PATCH 2/4] tracing: add rb_event_discard() hack


On Tue, 2009-03-17 at 21:21 -0400, Steven Rostedt wrote:
> On Tue, 17 Mar 2009, Tom Zanussi wrote:

> >  
> >  	rb_update_read_stamp(cpu_buffer, event);
> > @@ -2026,8 +2051,8 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
> >  	 * can have.  Nesting 10 deep of interrupts is clearly
> >  	 * an anomaly.
> >  	 */
> > -	if (RB_WARN_ON(cpu_buffer, ++nr_loops > 10))
> > -		return NULL;
> > +//	if (RB_WARN_ON(cpu_buffer, ++nr_loops > 10))
> > +//		return NULL;
> 
> Were you hitting this? If so, we need to investigate.
> 

I was hitting this, but only because my code would always loop around to
'again' for a discarded event.  So, 10 discarded events in a row would
trigger it.

I noticed that your fix returns instead, so it's no longer a problem.

Thanks,

Tom



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/