Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751062AbVLZI2l (ORCPT ); Mon, 26 Dec 2005 03:28:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751065AbVLZI2l (ORCPT ); Mon, 26 Dec 2005 03:28:41 -0500 Received: from fmr24.intel.com ([143.183.121.16]:37067 "EHLO scsfmr004.sc.intel.com") by vger.kernel.org with ESMTP id S1751060AbVLZI2k (ORCPT ); Mon, 26 Dec 2005 03:28:40 -0500 Date: Mon, 26 Dec 2005 00:28:39 -0800 From: Yanmin Zhang To: Greg KH Cc: Greg KH , linux-kernel@vger.kernel.org, discuss@x86-64.org, linux-ia64@vger.kernel.org, "Siddha, Suresh B" , "Shah, Rajesh" , "Pallipadi, Venkatesh" , yanmin.zhang@intel.com Subject: Re: [PATCH v2:3/3]Export cpu topology by sysfs Message-ID: <20051226002839.A24653@unix-os.sc.intel.com> References: <8126E4F969BA254AB43EA03C59F44E84044DE5EA@pdsmsx404> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit User-Agent: Mutt/1.2.5.1i In-Reply-To: <8126E4F969BA254AB43EA03C59F44E84044DE5EA@pdsmsx404>; from yanmin.zhang@intel.com on Mon, Dec 26, 2005 at 03:38:16PM +0800 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12325 Lines: 338 On Mon, Dec 26, 2005 at 03:38:16PM +0800, Zhang, Yanmin wrote: > >>-----Original Message----- > >>From: Greg KH [mailto:greg@kroah.com] > >>Sent: 2005??12??24?? 3:16 > >>To: Zhang, Yanmin > >>Cc: Yanmin Zhang; linux-kernel@vger.kernel.org; discuss@x86-64.org; linux-ia64@vger.kernel.org; Siddha, Suresh B; Shah, Rajesh; > >>Pallipadi, Venkatesh > >>Subject: Re: [PATCH v2:3/3]Export cpu topology by sysfs > >> > >>On Fri, Dec 23, 2005 at 12:03:27PM +0800, Zhang, Yanmin wrote: > >>> >>Can't you just use an attribute group and attach it to the cpu kobject? > >>> >>That would save an array of kobjects I think. > >>> As you know, current i386/x86_64 arch also export cache info under > >>> /sys/device/system/cpu/cpuX/cache. Is it clearer to export topology > >>> under a new directory than under cpu directly? > >> > >>No, the place in the sysfs tree you are putting this is just fine. I'm > >>just saying that you do not need to create a new kobject for these > >>attributes. Just use an attribute group, and you will get the same > >>naming, without the need for an extra kobject (and the whole array of > >>kobjects) at all. > >> > >>Does that make more sense? > Yes, indeed. Now, I used your idea and the patch became simpler. Thanks. > > > >> > >>> >>> +static int __cpuinit topology_cpu_callback(struct notifier_block *nfb, > >>> >>> + unsigned long action, void *hcpu) > >>> >>> +{ > >>> >>> + unsigned int cpu = (unsigned long)hcpu; > >>> >>> + struct sys_device *sys_dev; > >>> >>> + > >>> >>> + sys_dev = get_cpu_sysdev(cpu); > >>> >>> + switch (action) { > >>> >>> + case CPU_ONLINE: > >>> >>> + topology_add_dev(sys_dev); > >>> >>> + break; > >>> >>> +#ifdef CONFIG_HOTPLUG_CPU > >>> >>> + case CPU_DEAD: > >>> >>> + topology_remove_dev(sys_dev); > >>> >>> + break; > >>> >>> +#endif > >>> >> > >>> >>Why ifdef? Isn't it safe to just always have this in? > >>> If no ifdef here, gcc reported a compiling warning when I compiled it > >>> on IA64 with CONFIG_HOTPLUG_CPU=n. > >> > >>Then you should probably go change it so that CPU_DEAD is defined on > >>non-smp builds, otherwise the code gets quite messy like the above :) > > Sorry. My previous explanation is confusing. It's a link warning on ia64. On ia64, the kernel vmlinux doesn't include section .exit.text, so ld will report a link warning when a function is in section .exit.text and another function (not in .exit.text) calls the first one. When CONFIG_HOTPLUG_CPU=n, function topology_remove_dev is in section .exit.text, but its caller topology_remove_dev is not in .exit.text. > > i386 and x86_64 kernel vmlinux does include .exit.text and discard it only when running, so there is no such warning on i386/x86_64. > > There is no other better approach to get rid of the warning unless we change arch/ia64/kernel/vmlinux.lds.S to keep all .exit.text in kernel image. Here is the new patch. Thank Greg. --- diff -Nraup linux-2.6.15_rc3/arch/ia64/kernel/topology.c linux-2.6.15_rc3_topology/arch/ia64/kernel/topology.c --- linux-2.6.15_rc3/arch/ia64/kernel/topology.c 2001-06-06 08:57:20.000000000 +0800 +++ linux-2.6.15_rc3_topology/arch/ia64/kernel/topology.c 2001-06-06 08:55:35.000000000 +0800 @@ -98,4 +98,4 @@ out: return err; } -__initcall(topology_init); +subsys_initcall(topology_init); diff -Nraup linux-2.6.15_rc3/Documentation/cputopology.txt linux-2.6.15_rc3_topology/Documentation/cputopology.txt --- linux-2.6.15_rc3/Documentation/cputopology.txt 1970-01-01 08:00:00.000000000 +0800 +++ linux-2.6.15_rc3_topology/Documentation/cputopology.txt 2001-06-06 08:55:35.000000000 +0800 @@ -0,0 +1,31 @@ + +Export cpu topology info by sysfs. Items (attributes) are similar +to /proc/cpuinfo. + +1) /sys/devices/system/cpu/cpuX/topology/physical_package_id: +represent the physical package id of cpu X; +2) /sys/devices/system/cpu/cpuX/topology/core_id: +represent the cpu core id to cpu X; +3) /sys/devices/system/cpu/cpuX/topology/thread_id: +represent the cpu thread id to cpu X; +4) /sys/devices/system/cpu/cpuX/topology/thread_siblings: +represent the thread siblings to cpu X in the same core; +5) /sys/devices/system/cpu/cpuX/topology/core_siblings: +represent the thread siblings to cpu X in the same physical package; + +To implement it in an architecture-neutral way, a new source file, +driver/base/topology.c, is to export the 5 attributes. + +If one architecture wants to support this feature, it just needs to +implement 5 defines, typically in file include/asm-XXX/topology.h. +The 5 defines are: +#define topology_physical_package_id(cpu) +#define topology_core_id(cpu) +#define topology_thread_id(cpu) +#define topology_thread_siblings(cpu) +#define topology_core_siblings(cpu) + +The type of siblings is cpumask_t. + +If an attribute isn't defined on an architecture, it won't be exported. + diff -Nraup linux-2.6.15_rc3/drivers/base/Makefile linux-2.6.15_rc3_topology/drivers/base/Makefile --- linux-2.6.15_rc3/drivers/base/Makefile 2001-06-06 08:57:20.000000000 +0800 +++ linux-2.6.15_rc3_topology/drivers/base/Makefile 2001-06-06 08:55:35.000000000 +0800 @@ -8,6 +8,7 @@ obj-y += power/ obj-$(CONFIG_FW_LOADER) += firmware_class.o obj-$(CONFIG_NUMA) += node.o obj-$(CONFIG_MEMORY_HOTPLUG) += memory.o +obj-$(CONFIG_SMP) += topology.o ifeq ($(CONFIG_DEBUG_DRIVER),y) EXTRA_CFLAGS += -DDEBUG diff -Nraup linux-2.6.15_rc3/drivers/base/topology.c linux-2.6.15_rc3_topology/drivers/base/topology.c --- linux-2.6.15_rc3/drivers/base/topology.c 1970-01-01 08:00:00.000000000 +0800 +++ linux-2.6.15_rc3_topology/drivers/base/topology.c 2001-06-06 09:01:30.000000000 +0800 @@ -0,0 +1,159 @@ +/* + * driver/base/topology.c - Populate sysfs with cpu topology information + * + * Written by: Zhang Yanmin, Intel Corporation + * + * Copyright (C) 2005, Intel Corp. + * + * All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ +#include +#include +#include +#include +#include +#include + +#define define_one_ro(_name) \ +static SYSDEV_ATTR(_name, 0444, show_##_name, NULL) + +#define define_id_show_func(name) \ +static ssize_t show_##name(struct sys_device *dev, char *buf) \ +{ \ + unsigned int cpu = dev->id; \ + return sprintf(buf, "%d\n", topology_##name(cpu)); \ +} + +#define define_siblings_show_func(name) \ +static ssize_t show_##name(struct sys_device *dev, char *buf) \ +{ \ + ssize_t len = -1; \ + unsigned int cpu = dev->id; \ + len = cpumask_scnprintf(buf, NR_CPUS+1, topology_##name(cpu)); \ + return (len + sprintf(buf + len, "\n")); \ +} + +#ifdef topology_physical_package_id +define_id_show_func(physical_package_id); +define_one_ro(physical_package_id); +#define ref_physical_package_id_attr &attr_physical_package_id.attr, +#else +#define ref_physical_package_id_attr +#endif + +#ifdef topology_core_id +define_id_show_func(core_id); +define_one_ro(core_id); +#define ref_core_id_attr &attr_core_id.attr, +#else +#define ref_core_id_attr +#endif + +#ifdef topology_thread_id +define_id_show_func(thread_id); +define_one_ro(thread_id); +#define ref_thread_id_attr &attr_thread_id.attr, +#else +#define ref_thread_id_attr +#endif + +#ifdef topology_thread_siblings +define_siblings_show_func(thread_siblings); +define_one_ro(thread_siblings); +#define ref_thread_siblings_attr &attr_thread_siblings.attr, +#else +#define ref_thread_siblings_attr +#endif + +#ifdef topology_core_siblings +define_siblings_show_func(core_siblings); +define_one_ro(core_siblings); +#define ref_core_siblings_attr &attr_core_siblings.attr, +#else +#define ref_core_siblings_attr +#endif + +static struct attribute * default_attrs[] = { + ref_physical_package_id_attr + ref_core_id_attr + ref_thread_id_attr + ref_thread_siblings_attr + ref_core_siblings_attr + NULL +}; + +static struct attribute_group topology_attr_group = { + .attrs = default_attrs, + .name = "topology" +}; + +/* Add/Remove cpu_topology interface for CPU device */ +static int __cpuinit topology_add_dev(struct sys_device * sys_dev) +{ + sysfs_create_group(&sys_dev->kobj, &topology_attr_group); + return 0; +} + +static int __cpuexit topology_remove_dev(struct sys_device * sys_dev) +{ + sysfs_remove_group(&sys_dev->kobj, &topology_attr_group); + return 0; +} + +static int __cpuinit topology_cpu_callback(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + unsigned int cpu = (unsigned long)hcpu; + struct sys_device *sys_dev; + + sys_dev = get_cpu_sysdev(cpu); + switch (action) { + case CPU_ONLINE: + topology_add_dev(sys_dev); + break; +#ifdef CONFIG_HOTPLUG_CPU + case CPU_DEAD: + topology_remove_dev(sys_dev); + break; +#endif + } + return NOTIFY_OK; +} + +static struct notifier_block topology_cpu_notifier = +{ + .notifier_call = topology_cpu_callback, +}; + +static int __cpuinit topology_sysfs_init(void) +{ + int i; + + for_each_online_cpu(i) { + topology_cpu_callback(&topology_cpu_notifier, CPU_ONLINE, + (void *)(long)i); + } + + register_cpu_notifier(&topology_cpu_notifier); + + return 0; +} + +device_initcall(topology_sysfs_init); + diff -Nraup linux-2.6.15_rc3/include/asm-i386/topology.h linux-2.6.15_rc3_topology/include/asm-i386/topology.h --- linux-2.6.15_rc3/include/asm-i386/topology.h 2001-06-06 08:57:20.000000000 +0800 +++ linux-2.6.15_rc3_topology/include/asm-i386/topology.h 2001-06-06 08:55:35.000000000 +0800 @@ -27,6 +27,14 @@ #ifndef _ASM_I386_TOPOLOGY_H #define _ASM_I386_TOPOLOGY_H +#ifdef CONFIG_SMP +#define topology_physical_package_id(cpu) phys_proc_id[cpu] +#define topology_core_id(cpu) cpu_core_id[cpu] +#define topology_thread_id(cpu) cpu_thread_id[cpu] +#define topology_core_siblings(cpu) cpu_core_map[cpu] +#define topology_thread_siblings(cpu) cpu_sibling_map[cpu] +#endif + #ifdef CONFIG_NUMA #include diff -Nraup linux-2.6.15_rc3/include/asm-ia64/topology.h linux-2.6.15_rc3_topology/include/asm-ia64/topology.h --- linux-2.6.15_rc3/include/asm-ia64/topology.h 2001-06-06 08:57:20.000000000 +0800 +++ linux-2.6.15_rc3_topology/include/asm-ia64/topology.h 2001-06-06 08:55:35.000000000 +0800 @@ -100,6 +100,14 @@ void build_cpu_to_node_map(void); #endif /* CONFIG_NUMA */ +#ifdef CONFIG_SMP +#define topology_physical_package_id(cpu) cpu_data(cpu)->socket_id +#define topology_core_id(cpu) cpu_data(cpu)->core_id +#define topology_thread_id(cpu) cpu_data(cpu)->thread_id +#define topology_core_siblings(cpu) cpu_core_map[cpu] +#define topology_thread_siblings(cpu) cpu_sibling_map[cpu] +#endif + #include #endif /* _ASM_IA64_TOPOLOGY_H */ diff -Nraup linux-2.6.15_rc3/include/asm-x86_64/topology.h linux-2.6.15_rc3_topology/include/asm-x86_64/topology.h --- linux-2.6.15_rc3/include/asm-x86_64/topology.h 2001-06-06 08:57:20.000000000 +0800 +++ linux-2.6.15_rc3_topology/include/asm-x86_64/topology.h 2001-06-06 08:55:35.000000000 +0800 @@ -58,6 +58,14 @@ extern int __node_distance(int, int); #endif +#ifdef CONFIG_SMP +#define topology_physical_package_id(cpu) phys_proc_id[cpu] +#define topology_core_id(cpu) cpu_core_id[cpu] +#define topology_thread_id(cpu) cpu_thread_id[cpu] +#define topology_core_siblings(cpu) cpu_core_map[cpu] +#define topology_thread_siblings(cpu) cpu_sibling_map[cpu] +#endif + #include #endif - 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/