From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dave Hansen , Thomas Gleixner , Ingo Molnar Subject: [PATCH 4.17 33/97] x86/topology: Provide topology_smt_supported() Date: Tue, 14 Aug 2018 19:16:45 +0200 Message-Id: <20180814171434.436951422@linuxfoundation.org> In-Reply-To: <20180814171433.160434170@linuxfoundation.org> References: <20180814171433.160434170@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Gleixner commit f048c399e0f7490ab7296bc2c255d37eb14a9675 upstream Provide information whether SMT is supoorted by the CPUs. Preparatory patch for SMT control mechanism. Suggested-by: Dave Hansen Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/topology.h | 2 ++ arch/x86/kernel/smpboot.c | 8 ++++++++ 2 files changed, 10 insertions(+) --- a/arch/x86/include/asm/topology.h +++ b/arch/x86/include/asm/topology.h @@ -125,6 +125,7 @@ static inline int topology_max_smt_threa int topology_update_package_map(unsigned int apicid, unsigned int cpu); int topology_phys_to_logical_pkg(unsigned int pkg); bool topology_is_primary_thread(unsigned int cpu); +bool topology_smt_supported(void); #else #define topology_max_packages() (1) static inline int @@ -132,6 +133,7 @@ topology_update_package_map(unsigned int static inline int topology_phys_to_logical_pkg(unsigned int pkg) { return 0; } static inline int topology_max_smt_threads(void) { return 1; } static inline bool topology_is_primary_thread(unsigned int cpu) { return true; } +static inline bool topology_smt_supported(void) { return false; } #endif static inline void arch_fix_phys_package_id(int num, u32 slot) --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -282,6 +282,14 @@ bool topology_is_primary_thread(unsigned } /** + * topology_smt_supported - Check whether SMT is supported by the CPUs + */ +bool topology_smt_supported(void) +{ + return smp_num_siblings > 1; +} + +/** * topology_phys_to_logical_pkg - Map a physical package id to a logical * * Returns logical package id or -1 if not found