From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Richter Subject: Re: [PATCH 5/6] ARM: Make oprofile depend on CONFIG_HW_PERF_EVENTS Date: Thu, 16 Sep 2010 15:34:44 +0200 Message-ID: <20100916133444.GB13563@erda.amd.com> References: <831bc9523fe04ce899bc78230990033fbe009431.1284357372.git.matt@console-pimps.org> <1284367192.3042.2.camel@e102144-lin.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Received: from tx2ehsobe003.messaging.microsoft.com ([65.55.88.13]:13377 "EHLO TX2EHSOBE006.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751456Ab0IPNjx (ORCPT ); Thu, 16 Sep 2010 09:39:53 -0400 Content-Disposition: inline In-Reply-To: <1284367192.3042.2.camel@e102144-lin.cambridge.arm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Will Deacon Cc: Matt Fleming , Paul Mundt , Russell King , "linux-arm-kernel@lists.infradead.org" , "linux-sh@vger.kernel.org" , Peter Zijlstra , Ingo Molnar , Frederic Weisbecker , Arnaldo Carvalho de Melo , "linux-arch@vger.kernel.org" On 13.09.10 04:39:52, Will Deacon wrote: > Hi Matt, > > On Mon, 2010-09-13 at 07:07 +0100, Matt Fleming wrote: > > Currently, oprofile support is only functional if CONFIG_HW_PERF_EVENTS > > is set. If this symbol is not set, oprofile initialisation will fail at > > runtime. Instead of allowing the oprofile code to build but fail at > > runtime it seems less confusing to not allow the code to be built unless > > hardware performance counter support is available. > > > > Signed-off-by: Matt Fleming > > --- > > arch/arm/Kconfig | 2 +- > > arch/arm/oprofile/common.c | 9 --------- > > 2 files changed, 1 insertions(+), 10 deletions(-) > When oprofile_arch_init fails (-ENODEV), oprofile will fall back to > timer mode. With this patch, how can you make use of a timer fallback? True, if you want an error at compile time, maybe we use the #error pragma instead. But falling back to timer mode is fine to me too. Will leave that decision to the arm folks. -Robert > > I'll try and get around to testing the rest of this series today. > > Cheers, > > Will > > > > -- Advanced Micro Devices, Inc. Operating System Research Center From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Richter Date: Thu, 16 Sep 2010 13:34:44 +0000 Subject: Re: [PATCH 5/6] ARM: Make oprofile depend on CONFIG_HW_PERF_EVENTS Message-Id: <20100916133444.GB13563@erda.amd.com> List-Id: References: <831bc9523fe04ce899bc78230990033fbe009431.1284357372.git.matt@console-pimps.org> In-Reply-To: <831bc9523fe04ce899bc78230990033fbe009431.1284357372.git.matt@console-pimps.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org On 13.09.10 04:39:52, Will Deacon wrote: > Hi Matt, > > On Mon, 2010-09-13 at 07:07 +0100, Matt Fleming wrote: > > Currently, oprofile support is only functional if CONFIG_HW_PERF_EVENTS > > is set. If this symbol is not set, oprofile initialisation will fail at > > runtime. Instead of allowing the oprofile code to build but fail at > > runtime it seems less confusing to not allow the code to be built unless > > hardware performance counter support is available. > > > > Signed-off-by: Matt Fleming > > --- > > arch/arm/Kconfig | 2 +- > > arch/arm/oprofile/common.c | 9 --------- > > 2 files changed, 1 insertions(+), 10 deletions(-) > When oprofile_arch_init fails (-ENODEV), oprofile will fall back to > timer mode. With this patch, how can you make use of a timer fallback? True, if you want an error at compile time, maybe we use the #error pragma instead. But falling back to timer mode is fine to me too. Will leave that decision to the arm folks. -Robert > > I'll try and get around to testing the rest of this series today. > > Cheers, > > Will > > > > -- Advanced Micro Devices, Inc. Operating System Research Center From mboxrd@z Thu Jan 1 00:00:00 1970 From: robert.richter@amd.com (Robert Richter) Date: Thu, 16 Sep 2010 15:34:44 +0200 Subject: [PATCH 5/6] ARM: Make oprofile depend on CONFIG_HW_PERF_EVENTS In-Reply-To: <1284367192.3042.2.camel@e102144-lin.cambridge.arm.com> References: <831bc9523fe04ce899bc78230990033fbe009431.1284357372.git.matt@console-pimps.org> <1284367192.3042.2.camel@e102144-lin.cambridge.arm.com> Message-ID: <20100916133444.GB13563@erda.amd.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 13.09.10 04:39:52, Will Deacon wrote: > Hi Matt, > > On Mon, 2010-09-13 at 07:07 +0100, Matt Fleming wrote: > > Currently, oprofile support is only functional if CONFIG_HW_PERF_EVENTS > > is set. If this symbol is not set, oprofile initialisation will fail at > > runtime. Instead of allowing the oprofile code to build but fail at > > runtime it seems less confusing to not allow the code to be built unless > > hardware performance counter support is available. > > > > Signed-off-by: Matt Fleming > > --- > > arch/arm/Kconfig | 2 +- > > arch/arm/oprofile/common.c | 9 --------- > > 2 files changed, 1 insertions(+), 10 deletions(-) > When oprofile_arch_init fails (-ENODEV), oprofile will fall back to > timer mode. With this patch, how can you make use of a timer fallback? True, if you want an error at compile time, maybe we use the #error pragma instead. But falling back to timer mode is fine to me too. Will leave that decision to the arm folks. -Robert > > I'll try and get around to testing the rest of this series today. > > Cheers, > > Will > > > > -- Advanced Micro Devices, Inc. Operating System Research Center