Subject: Re: TRACE: config warning for IRQSOFF_TRACER
From: Steven Rostedt <rostedt@goodmis.org>
To: Richard Kennedy <richard@rsk.demon.co.uk>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
        lkml <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@redhat.com>
In-Reply-To: <1282402332.1978.32.camel@castor.rsk>
References: <1282402332.1978.32.camel@castor.rsk>
Content-Type: text/plain; charset="ISO-8859-15"
Date: Mon, 30 Aug 2010 20:47:33 -0400
Message-ID: <1283215653.1377.41.camel@gandalf.stny.rr.com>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1182
Lines: 31

On Sat, 2010-08-21 at 15:52 +0100, Richard Kennedy wrote: 
> In my config with PROVE_LOCKING=n and FTRACE=y (which defaults
> IRQSOFF_TRACER to y), I get the following warning from make oldconfig.
> 
> scripts/kconfig/conf --oldconfig arch/x86/Kconfig
> warning: (IRQSOFF_TRACER && TRACING_SUPPORT && FTRACE &&
> TRACE_IRQFLAGS_SUPPORT && !ARCH_USES_GETTIMEOFFSET) selects
> TRACE_IRQFLAGS which has unmet direct dependencies (DEBUG_KERNEL &&
> TRACE_IRQFLAGS_SUPPORT && PROVE_LOCKING)
> 
> The problem is that TRACE_IRQFLAGS depends on PROVE_LOCKING.
> Should it select PROVE_LOCKING instead? or is there a better way to fix
> this?

The TRACE_IRQFLAGS was originally written for lockdep, but it is now
used by Ftrace's irqsoff tracer.

I just compiled and booted with TRACE_IRQFLAGS=y and PROVE_LOCKING not
set, and it worked fine.

I think the correct patch is to remove the dependency of TRACE_IRQFLAGS
on PROVE_LOCKING.

-- Steve


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