From fad12ac8c8c2591c7f4e61d19b6a9d76cd49fafa Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Thu, 26 Jan 2012 00:09:14 +0100 Subject: [PATCH] CPU: Introduce ARCH_HAS_CPU_AUTOPROBE and X86 parts This patch is based on Andi Kleen's work: Implement autoprobing/loading of modules serving CPU specific features (x86cpu autoloading). And Kay Siever's work to get rid of sysdev cpu structures and making use of struct device instead. Before, the cpuid driver had to be loaded to get the x86cpu autoloading feature. With this patch autoloading works through the /sys/devices/system/cpu object Cc: Kay Sievers Cc: Dave Jones Cc: Jens Axboe Cc: Herbert Xu Cc: Huang Ying Cc: Len Brown Acked-by: Andi Kleen Signed-off-by: Thomas Renninger Acked-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- arch/x86/Kconfig | 3 ++ arch/x86/kernel/cpu/match.c | 44 +++++++++++++++++++++++++++ arch/x86/kernel/cpuid.c | 59 +------------------------------------ drivers/base/cpu.c | 11 +++++++ include/linux/cpu.h | 7 +++++ 5 files changed, 66 insertions(+), 58 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 864cc6e6ac8..6baa1e66e1b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -179,6 +179,9 @@ config ARCH_HAS_DEFAULT_IDLE config ARCH_HAS_CACHE_LINE_SIZE def_bool y +config ARCH_HAS_CPU_AUTOPROBE + def_bool y + config HAVE_SETUP_PER_CPU_AREA def_bool y diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c index 7acc961422e..940e2d48307 100644 --- a/arch/x86/kernel/cpu/match.c +++ b/arch/x86/kernel/cpu/match.c @@ -2,6 +2,7 @@ #include #include #include +#include /** * x86_match_cpu - match current CPU again an array of x86_cpu_ids @@ -46,3 +47,46 @@ const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match) return NULL; } EXPORT_SYMBOL(x86_match_cpu); + +ssize_t arch_print_cpu_modalias(struct device *dev, + struct device_attribute *attr, + char *bufptr) +{ + int size = PAGE_SIZE; + int i, n; + char *buf = bufptr; + + n = snprintf(buf, size, "x86cpu:vendor:%04X:family:%04X:" + "model:%04X:feature:", + boot_cpu_data.x86_vendor, + boot_cpu_data.x86, + boot_cpu_data.x86_model); + size -= n; + buf += n; + size -= 2; + for (i = 0; i < NCAPINTS*32; i++) { + if (boot_cpu_has(i)) { + n = snprintf(buf, size, ",%04X", i); + if (n < 0) { + WARN(1, "x86 features overflow page\n"); + break; + } + size -= n; + buf += n; + } + } + *buf++ = ','; + *buf++ = '\n'; + return buf - bufptr; +} + +int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (buf) { + arch_print_cpu_modalias(NULL, NULL, buf); + add_uevent_var(env, "MODALIAS=%s", buf); + kfree(buf); + } + return 0; +} diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c index 7c89880eefd..a524353d93f 100644 --- a/arch/x86/kernel/cpuid.c +++ b/arch/x86/kernel/cpuid.c @@ -40,7 +40,6 @@ #include #include #include -#include #include #include @@ -139,57 +138,13 @@ static const struct file_operations cpuid_fops = { .open = cpuid_open, }; -static ssize_t print_cpu_modalias(struct device *dev, - struct device_attribute *attr, - char *bufptr) -{ - int size = PAGE_SIZE; - int i, n; - char *buf = bufptr; - - n = snprintf(buf, size, "x86cpu:vendor:%04X:family:" - "%04X:model:%04X:feature:", - boot_cpu_data.x86_vendor, - boot_cpu_data.x86, - boot_cpu_data.x86_model); - size -= n; - buf += n; - size -= 2; - for (i = 0; i < NCAPINTS*32; i++) { - if (boot_cpu_has(i)) { - n = snprintf(buf, size, ",%04X", i); - if (n < 0) { - WARN(1, "x86 features overflow page\n"); - break; - } - size -= n; - buf += n; - } - } - *buf++ = ','; - *buf++ = '\n'; - return buf - bufptr; -} - -static DEVICE_ATTR(modalias, 0444, print_cpu_modalias, NULL); - static __cpuinit int cpuid_device_create(int cpu) { struct device *dev; - int err; dev = device_create(cpuid_class, NULL, MKDEV(CPUID_MAJOR, cpu), NULL, "cpu%d", cpu); - if (IS_ERR(dev)) - return PTR_ERR(dev); - - err = device_create_file(dev, &dev_attr_modalias); - if (err) { - /* keep device around on error. attribute is optional. */ - err = 0; - } - - return 0; + return IS_ERR(dev) ? PTR_ERR(dev) : 0; } static void cpuid_device_destroy(int cpu) @@ -227,17 +182,6 @@ static char *cpuid_devnode(struct device *dev, umode_t *mode) return kasprintf(GFP_KERNEL, "cpu/%u/cpuid", MINOR(dev->devt)); } -static int cpuid_dev_uevent(struct device *dev, struct kobj_uevent_env *env) -{ - char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (buf) { - print_cpu_modalias(NULL, NULL, buf); - add_uevent_var(env, "MODALIAS=%s", buf); - kfree(buf); - } - return 0; -} - static int __init cpuid_init(void) { int i, err = 0; @@ -256,7 +200,6 @@ static int __init cpuid_init(void) goto out_chrdev; } cpuid_class->devnode = cpuid_devnode; - cpuid_class->dev_uevent = cpuid_dev_uevent; for_each_online_cpu(i) { err = cpuid_device_create(i); if (err != 0) diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index db87e78d745..2a0c670c281 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include "base.h" @@ -223,6 +224,9 @@ int __cpuinit register_cpu(struct cpu *cpu, int num) cpu->node_id = cpu_to_node(num); cpu->dev.id = num; cpu->dev.bus = &cpu_subsys; +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE + cpu->dev.bus->uevent = arch_cpu_uevent; +#endif error = device_register(&cpu->dev); if (!error && cpu->hotpluggable) register_cpu_control(cpu); @@ -247,6 +251,10 @@ struct device *get_cpu_device(unsigned cpu) } EXPORT_SYMBOL_GPL(get_cpu_device); +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE +static DEVICE_ATTR(modalias, 0444, arch_print_cpu_modalias, NULL); +#endif + static struct attribute *cpu_root_attrs[] = { #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE &dev_attr_probe.attr, @@ -257,6 +265,9 @@ static struct attribute *cpu_root_attrs[] = { &cpu_attrs[2].attr.attr, &dev_attr_kernel_max.attr, &dev_attr_offline.attr, +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE + &dev_attr_modalias.attr, +#endif NULL }; diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 1f6587590a1..6e53b4823d7 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -44,6 +44,13 @@ extern ssize_t arch_cpu_release(const char *, size_t); #endif struct notifier_block; +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE +extern int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env); +extern ssize_t arch_print_cpu_modalias(struct device *dev, + struct device_attribute *attr, + char *bufptr); +#endif + /* * CPU notifier priorities. */ -- 2.39.5