Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752950AbbH0R1z (ORCPT ); Thu, 27 Aug 2015 13:27:55 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:37310 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750967AbbH0R1x (ORCPT ); Thu, 27 Aug 2015 13:27:53 -0400 Date: Thu, 27 Aug 2015 10:27:46 -0700 From: Guenter Roeck To: Huang Rui Cc: Borislav Petkov , Jean Delvare , Andy Lutomirski , Andreas Herrmann , Thomas Gleixner , Peter Zijlstra , Ingo Molnar , "Rafael J. Wysocki" , Len Brown , John Stultz , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org, x86@kernel.org, Andreas Herrmann , Aravind Gopalakrishnan , Borislav Petkov , Fengguang Wu , Aaron Lu , Tony Li Subject: Re: [PATCH 09/15] x86, amd: add accessor for number of cores per compute unit Message-ID: <20150827172746.GA27452@roeck-us.net> References: <1440662866-28716-1-git-send-email-ray.huang@amd.com> <1440662866-28716-10-git-send-email-ray.huang@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1440662866-28716-10-git-send-email-ray.huang@amd.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=0.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3161 Lines: 98 On Thu, Aug 27, 2015 at 04:07:40PM +0800, Huang Rui wrote: > Add an accessor function amd_get_cores_per_cu() which returns the > number of cores per compute unit. > > In a subsequent patch, we will use this function in fam15h_power > driver. > > Signed-off-by: Huang Rui > --- > arch/x86/include/asm/processor.h | 1 + > arch/x86/kernel/cpu/amd.c | 19 +++++++++++++++++-- > 2 files changed, 18 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h > index 19577dd..831ad682 100644 > --- a/arch/x86/include/asm/processor.h > +++ b/arch/x86/include/asm/processor.h > @@ -810,6 +810,7 @@ static inline int mpx_disable_management(void) > > extern u16 amd_get_nb_id(int cpu); > extern u32 amd_get_nodes_per_socket(void); > +extern u32 amd_get_cores_per_cu(void); > > static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves) > { > diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c > index 51ad2af..8ab939a 100644 > --- a/arch/x86/kernel/cpu/amd.c > +++ b/arch/x86/kernel/cpu/amd.c > @@ -26,6 +26,9 @@ > */ > static u32 nodes_per_socket = 1; > > +/* cores_per_cu: stores the number of cores per compute unit */ > +static u32 cores_per_cu = 1; > + Is this value going to be constant even if there are multiple CPUs in the system ? In other words, if there are multiple CPUs, do they always have to have the same number of cores per CU ? Thanks, Guenter > static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p) > { > u32 gprs[8] = { 0 }; > @@ -298,7 +301,6 @@ static int nearby_node(int apicid) > #ifdef CONFIG_SMP > static void amd_get_topology(struct cpuinfo_x86 *c) > { > - u32 cores_per_cu = 1; > u8 node_id; > int cpu = smp_processor_id(); > > @@ -313,7 +315,6 @@ static void amd_get_topology(struct cpuinfo_x86 *c) > /* get compute unit information */ > smp_num_siblings = ((ebx >> 8) & 3) + 1; > c->compute_unit_id = ebx & 0xff; > - cores_per_cu += ((ebx >> 8) & 3); > } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) { > u64 value; > > @@ -379,6 +380,13 @@ u32 amd_get_nodes_per_socket(void) > } > EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket); > > +/* this function returns the number of cores per compute unit */ > +u32 amd_get_cores_per_cu(void) > +{ > + return cores_per_cu; > +} > +EXPORT_SYMBOL_GPL(amd_get_cores_per_cu); > + > static void srat_detect_node(struct cpuinfo_x86 *c) > { > #ifdef CONFIG_NUMA > @@ -506,6 +514,13 @@ static void bsp_init_amd(struct cpuinfo_x86 *c) > /* A random value per boot for bit slice [12:upper_bit) */ > va_align.bits = get_random_int() & va_align.mask; > } > + > + if (cpu_has_topoext) { > + u32 cpuid; > + > + cpuid = cpuid_ebx(0x8000001e); > + cores_per_cu += ((cpuid >> 8) & 3); > + } > } > > static void early_init_amd(struct cpuinfo_x86 *c) > -- > 1.9.1 > -- 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/