From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754032AbeBGKi2 (ORCPT ); Wed, 7 Feb 2018 05:38:28 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:48506 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753732AbeBGKi0 (ORCPT ); Wed, 7 Feb 2018 05:38:26 -0500 Date: Wed, 7 Feb 2018 10:38:22 +0000 From: Dave Martin To: Suzuki K Poulose Cc: linux-arm-kernel@lists.infradead.org, mark.rutland@arm.com, ckadabi@codeaurora.org, ard.biesheuvel@linaro.org, marc.zyngier@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, jnair@caviumnetworks.com, dave.martin@arm.com Subject: Re: [PATCH v2 07/20] arm64: capabilities: Filter the entries based on a given mask Message-ID: <20180207103821.GX5862@e103592.cambridge.arm.com> References: <20180131182807.32134-1-suzuki.poulose@arm.com> <20180131182807.32134-8-suzuki.poulose@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180131182807.32134-8-suzuki.poulose@arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 31, 2018 at 06:27:54PM +0000, Suzuki K Poulose wrote: > While processing the list of capabilities, it is useful to > filter out some of the entries based on the given mask for the > scope of the capabilities to allow better control. This can be > used later for handling LOCAL vs SYSTEM wide capabilities and more. > All capabilities should have their scope set to either LOCAL_CPU or > SYSTEM. No functional/flow change. > > Cc: Dave Martin > Cc: Will Deacon > Cc: Mark Rutland > Signed-off-by: Suzuki K Poulose > --- > arch/arm64/include/asm/cpufeature.h | 2 ++ > arch/arm64/kernel/cpufeature.c | 35 ++++++++++++++++++++++++----------- > 2 files changed, 26 insertions(+), 11 deletions(-) > > diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h > index 69b5ce366598..cda62b70d338 100644 > --- a/arch/arm64/include/asm/cpufeature.h > +++ b/arch/arm64/include/asm/cpufeature.h > @@ -198,6 +198,8 @@ extern struct arm64_ftr_reg arm64_ftr_reg_ctrel0; > /* Is it safe for a late CPU to miss this capability when system has it */ > #define ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU ((u16)BIT(5)) > > +#define ARM64_CPUCAP_SCOPE_ALL \ > + (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_SCOPE_SYSTEM) Perhaps we could just use _MASK rather than having a separate #define, but it's good either way. Is there a situation in which _ALL and _MASK would need to be different? > /* > * CPU errata detected at boot time based on feature of one or more CPUs. > * It is not safe for a late CPU to have this feature when the system doesn't > diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c > index 5e4d581c97f1..5163dc51b975 100644 > --- a/arch/arm64/kernel/cpufeature.c > +++ b/arch/arm64/kernel/cpufeature.c > @@ -1185,10 +1185,12 @@ static bool __this_cpu_has_cap(const struct arm64_cpu_capabilities *cap_array, > } > > static void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, > - const char *info) > + u16 scope_mask, const char *info) > { > + scope_mask &= ARM64_CPUCAP_SCOPE_MASK; > for (; caps->matches; caps++) { > - if (!caps->matches(caps, cpucap_default_scope(caps))) > + if (!(caps->type & scope_mask) || > + !caps->matches(caps, cpucap_default_scope(caps))) > continue; > > if (!cpus_have_cap(caps->capability) && caps->desc) > @@ -1210,12 +1212,14 @@ static int __enable_cpu_capability(void *arg) > * Run through the enabled capabilities and enable() it on all active > * CPUs > */ > -static void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps) > +static void __init > +enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps, u16 scope_mask) > { > + scope_mask &= ARM64_CPUCAP_SCOPE_MASK; > for (; caps->matches; caps++) { > unsigned int num = caps->capability; > > - if (!cpus_have_cap(num)) > + if (!(caps->type & scope_mask) || !cpus_have_cap(num)) > continue; > > /* Ensure cpus_have_const_cap(num) works */ > @@ -1240,12 +1244,18 @@ static void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities * > * > * Returns "false" on conflicts. > */ > -static bool __verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps_list) > +static bool __verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps_list, > + u16 scope_mask) > { > bool cpu_has_cap, system_has_cap; > const struct arm64_cpu_capabilities *caps = caps_list; > > + scope_mask &= ARM64_CPUCAP_SCOPE_MASK; > for (; caps->matches; caps++) { > + Nit: extra blank line? [...] With that fixed, Reviewed-by: Dave Martin