From e9eee03e99d519599eb615c3e251d5f6cc4be57d Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 8 Apr 2009 12:31:17 +0200 Subject: [PATCH] x86, mce: clean up mce_64.c This file has been modified many times along the years, by multiple authors, so the general style and structure has diverged in a number of areas making this file hard to read. So fix the coding style match that of the rest of the x86 arch code. [ Impact: cleanup ] Signed-off-by: Ingo Molnar Signed-off-by: Hidetoshi Seto Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/mcheck/mce_64.c | 247 +++++++++++++++++----------- 1 file changed, 149 insertions(+), 98 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c index 77effb55afe7..1491246c4d69 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_64.c +++ b/arch/x86/kernel/cpu/mcheck/mce_64.c @@ -1,46 +1,47 @@ /* * Machine check handler. + * * K8 parts Copyright 2002,2003 Andi Kleen, SuSE Labs. * Rest from unknown author(s). * 2004 Andi Kleen. Rewrote most of it. * Copyright 2008 Intel Corporation * Author: Andi Kleen */ - -#include -#include -#include -#include +#include +#include +#include +#include +#include +#include #include +#include +#include +#include +#include #include -#include -#include #include -#include -#include -#include -#include -#include -#include -#include #include -#include -#include -#include +#include #include -#include +#include +#include +#include +#include +#include +#include + #include -#include -#include #include -#include #include +#include +#include +#include -#define MISC_MCELOG_MINOR 227 +#define MISC_MCELOG_MINOR 227 atomic_t mce_entry; -static int mce_dont_init; +static int mce_dont_init; /* * Tolerant levels: @@ -49,16 +50,16 @@ static int mce_dont_init; * 2: SIGBUS or log uncorrected errors (if possible), log corrected errors * 3: never panic or SIGBUS, log all errors (for testing only) */ -static int tolerant = 1; -static int banks; -static u64 *bank; -static unsigned long notify_user; -static int rip_msr; -static int mce_bootlog = -1; -static atomic_t mce_events; +static int tolerant = 1; +static int banks; +static u64 *bank; +static unsigned long notify_user; +static int rip_msr; +static int mce_bootlog = -1; +static atomic_t mce_events; -static char trigger[128]; -static char *trigger_argv[2] = { trigger, NULL }; +static char trigger[128]; +static char *trigger_argv[2] = { trigger, NULL }; static DECLARE_WAIT_QUEUE_HEAD(mce_wait); @@ -89,19 +90,23 @@ static struct mce_log mcelog = { void mce_log(struct mce *mce) { unsigned next, entry; + atomic_inc(&mce_events); mce->finished = 0; wmb(); for (;;) { entry = rcu_dereference(mcelog.next); for (;;) { - /* When the buffer fills up discard new entries. Assume - that the earlier errors are the more interesting. */ + /* + * When the buffer fills up discard new entries. + * Assume that the earlier errors are the more + * interesting ones: + */ if (entry >= MCE_LOG_LEN) { set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog.flags); return; } - /* Old left over entry. Skip. */ + /* Old left over entry. Skip: */ if (mcelog.entry[entry].finished) { entry++; continue; @@ -264,12 +269,12 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b) * implies that most kernel services cannot be safely used. Don't even * think about putting a printk in there! */ -void do_machine_check(struct pt_regs * regs, long error_code) +void do_machine_check(struct pt_regs *regs, long error_code) { struct mce m, panicm; + int panicm_found = 0; u64 mcestart = 0; int i; - int panicm_found = 0; /* * If no_way_out gets set, there is no safe way to recover from this * MCE. If tolerant is cranked up, we'll try anyway. @@ -293,6 +298,7 @@ void do_machine_check(struct pt_regs * regs, long error_code) mce_setup(&m); rdmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus); + /* if the restart IP is not valid, we're done for */ if (!(m.mcgstatus & MCG_STATUS_RIPV)) no_way_out = 1; @@ -356,23 +362,29 @@ void do_machine_check(struct pt_regs * regs, long error_code) mce_get_rip(&m, regs); mce_log(&m); - /* Did this bank cause the exception? */ - /* Assume that the bank with uncorrectable errors did it, - and that there is only a single one. */ - if ((m.status & MCI_STATUS_UC) && (m.status & MCI_STATUS_EN)) { + /* + * Did this bank cause the exception? + * + * Assume that the bank with uncorrectable errors did it, + * and that there is only a single one: + */ + if ((m.status & MCI_STATUS_UC) && + (m.status & MCI_STATUS_EN)) { panicm = m; panicm_found = 1; } } - /* If we didn't find an uncorrectable error, pick - the last one (shouldn't happen, just being safe). */ + /* + * If we didn't find an uncorrectable error, pick + * the last one (shouldn't happen, just being safe). + */ if (!panicm_found) panicm = m; /* * If we have decided that we just CAN'T continue, and the user - * has not set tolerant to an insane level, give up and die. + * has not set tolerant to an insane level, give up and die. */ if (no_way_out && tolerant < 3) mce_panic("Machine check", &panicm, mcestart); @@ -451,10 +463,9 @@ void mce_log_therm_throt_event(__u64 status) * poller finds an MCE, poll 2x faster. When the poller finds no more * errors, poll 2x slower (up to check_interval seconds). */ - static int check_interval = 5 * 60; /* 5 minutes */ + static DEFINE_PER_CPU(int, next_interval); /* in jiffies */ -static void mcheck_timer(unsigned long); static DEFINE_PER_CPU(struct timer_list, mce_timer); static void mcheck_timer(unsigned long data) @@ -464,9 +475,10 @@ static void mcheck_timer(unsigned long data) WARN_ON(smp_processor_id() != data); - if (mce_available(¤t_cpu_data)) + if (mce_available(¤t_cpu_data)) { machine_check_poll(MCP_TIMESTAMP, &__get_cpu_var(mce_poll_banks)); + } /* * Alert userspace if needed. If we logged an MCE, reduce the @@ -501,6 +513,7 @@ int mce_notify_user(void) static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2); clear_thread_flag(TIF_MCE_NOTIFY); + if (test_and_clear_bit(0, ¬ify_user)) { wake_up_interruptible(&mce_wait); @@ -520,9 +533,10 @@ int mce_notify_user(void) return 0; } -/* see if the idle task needs to notify userspace */ +/* see if the idle task needs to notify userspace: */ static int -mce_idle_callback(struct notifier_block *nfb, unsigned long action, void *junk) +mce_idle_callback(struct notifier_block *nfb, unsigned long action, + void *unused) { /* IDLE_END should be safe - interrupts are back on */ if (action == IDLE_END && test_thread_flag(TIF_MCE_NOTIFY)) @@ -532,7 +546,7 @@ mce_idle_callback(struct notifier_block *nfb, unsigned long action, void *junk) } static struct notifier_block mce_idle_notifier = { - .notifier_call = mce_idle_callback, + .notifier_call = mce_idle_callback, }; static __init int periodic_mcheck_init(void) @@ -547,8 +561,8 @@ __initcall(periodic_mcheck_init); */ static int mce_cap_init(void) { - u64 cap; unsigned b; + u64 cap; rdmsrl(MSR_IA32_MCG_CAP, cap); b = cap & 0xff; @@ -578,9 +592,9 @@ static int mce_cap_init(void) static void mce_init(void *dummy) { + mce_banks_t all_banks; u64 cap; int i; - mce_banks_t all_banks; /* * Log the machine checks left over from the previous reset. @@ -605,14 +619,21 @@ static void mce_cpu_quirks(struct cpuinfo_x86 *c) { /* This should be disabled by the BIOS, but isn't always */ if (c->x86_vendor == X86_VENDOR_AMD) { - if (c->x86 == 15 && banks > 4) - /* disable GART TBL walk error reporting, which trips off - incorrectly with the IOMMU & 3ware & Cerberus. */ + if (c->x86 == 15 && banks > 4) { + /* + * disable GART TBL walk error reporting, which + * trips off incorrectly with the IOMMU & 3ware + * & Cerberus: + */ clear_bit(10, (unsigned long *)&bank[4]); - if(c->x86 <= 17 && mce_bootlog < 0) - /* Lots of broken BIOS around that don't clear them - by default and leave crap in there. Don't log. */ + } + if (c->x86 <= 17 && mce_bootlog < 0) { + /* + * Lots of broken BIOS around that don't clear them + * by default and leave crap in there. Don't log: + */ mce_bootlog = 0; + } } } @@ -646,7 +667,7 @@ static void mce_init_timer(void) /* * Called for each booted CPU to set up machine checks. - * Must be called with preempt off. + * Must be called with preempt off: */ void __cpuinit mcheck_init(struct cpuinfo_x86 *c) { @@ -669,8 +690,8 @@ void __cpuinit mcheck_init(struct cpuinfo_x86 *c) */ static DEFINE_SPINLOCK(mce_state_lock); -static int open_count; /* #times opened */ -static int open_exclu; /* already open exclusive? */ +static int open_count; /* #times opened */ +static int open_exclu; /* already open exclusive? */ static int mce_open(struct inode *inode, struct file *file) { @@ -680,6 +701,7 @@ static int mce_open(struct inode *inode, struct file *file) if (open_exclu || (open_count && (file->f_flags & O_EXCL))) { spin_unlock(&mce_state_lock); unlock_kernel(); + return -EBUSY; } @@ -712,13 +734,14 @@ static void collect_tscs(void *data) rdtscll(cpu_tsc[smp_processor_id()]); } +static DEFINE_MUTEX(mce_read_mutex); + static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize, loff_t *off) { + char __user *buf = ubuf; unsigned long *cpu_tsc; - static DEFINE_MUTEX(mce_read_mutex); unsigned prev, next; - char __user *buf = ubuf; int i, err; cpu_tsc = kmalloc(nr_cpu_ids * sizeof(long), GFP_KERNEL); @@ -732,6 +755,7 @@ static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize, if (*off != 0 || usize < MCE_LOG_LEN*sizeof(struct mce)) { mutex_unlock(&mce_read_mutex); kfree(cpu_tsc); + return -EINVAL; } @@ -770,6 +794,7 @@ timeout: * synchronize. */ on_each_cpu(collect_tscs, cpu_tsc, 1); + for (i = next; i < MCE_LOG_LEN; i++) { if (mcelog.entry[i].finished && mcelog.entry[i].tsc < cpu_tsc[mcelog.entry[i].cpu]) { @@ -782,6 +807,7 @@ timeout: } mutex_unlock(&mce_read_mutex); kfree(cpu_tsc); + return err ? -EFAULT : buf - ubuf; } @@ -799,6 +825,7 @@ static long mce_ioctl(struct file *f, unsigned int cmd, unsigned long arg) if (!capable(CAP_SYS_ADMIN)) return -EPERM; + switch (cmd) { case MCE_GET_RECORD_LEN: return put_user(sizeof(struct mce), p); @@ -810,6 +837,7 @@ static long mce_ioctl(struct file *f, unsigned int cmd, unsigned long arg) do { flags = mcelog.flags; } while (cmpxchg(&mcelog.flags, flags, 0) != flags); + return put_user(flags, p); } default: @@ -818,11 +846,11 @@ static long mce_ioctl(struct file *f, unsigned int cmd, unsigned long arg) } static const struct file_operations mce_chrdev_ops = { - .open = mce_open, - .release = mce_release, - .read = mce_read, - .poll = mce_poll, - .unlocked_ioctl = mce_ioctl, + .open = mce_open, + .release = mce_release, + .read = mce_read, + .poll = mce_poll, + .unlocked_ioctl = mce_ioctl, }; static struct miscdevice mce_log_device = { @@ -891,13 +919,16 @@ static int mce_shutdown(struct sys_device *dev) return mce_disable(); } -/* On resume clear all MCE state. Don't want to see leftovers from the BIOS. - Only one CPU is active at this time, the others get readded later using - CPU hotplug. */ +/* + * On resume clear all MCE state. Don't want to see leftovers from the BIOS. + * Only one CPU is active at this time, the others get re-added later using + * CPU hotplug: + */ static int mce_resume(struct sys_device *dev) { mce_init(NULL); mce_cpu_features(¤t_cpu_data); + return 0; } @@ -916,14 +947,16 @@ static void mce_restart(void) } static struct sysdev_class mce_sysclass = { - .suspend = mce_suspend, - .shutdown = mce_shutdown, - .resume = mce_resume, - .name = "machinecheck", + .suspend = mce_suspend, + .shutdown = mce_shutdown, + .resume = mce_resume, + .name = "machinecheck", }; DEFINE_PER_CPU(struct sys_device, device_mce); -void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu) __cpuinitdata; + +__cpuinitdata +void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu); /* Why are there no generic functions for this? */ #define ACCESSOR(name, var, start) \ @@ -937,9 +970,12 @@ void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu) __cpuinit const char *buf, size_t siz) { \ char *end; \ unsigned long new = simple_strtoul(buf, &end, 0); \ - if (end == buf) return -EINVAL; \ + \ + if (end == buf) \ + return -EINVAL; \ var = new; \ start; \ + \ return end-buf; \ } \ static SYSDEV_ATTR(name, 0644, show_ ## name, set_ ## name); @@ -950,6 +986,7 @@ static ssize_t show_bank(struct sys_device *s, struct sysdev_attribute *attr, char *buf) { u64 b = bank[attr - bank_attrs]; + return sprintf(buf, "%llx\n", b); } @@ -958,15 +995,18 @@ static ssize_t set_bank(struct sys_device *s, struct sysdev_attribute *attr, { char *end; u64 new = simple_strtoull(buf, &end, 0); + if (end == buf) return -EINVAL; + bank[attr - bank_attrs] = new; mce_restart(); + return end-buf; } -static ssize_t show_trigger(struct sys_device *s, struct sysdev_attribute *attr, - char *buf) +static ssize_t +show_trigger(struct sys_device *s, struct sysdev_attribute *attr, char *buf) { strcpy(buf, trigger); strcat(buf, "\n"); @@ -974,21 +1014,27 @@ static ssize_t show_trigger(struct sys_device *s, struct sysdev_attribute *attr, } static ssize_t set_trigger(struct sys_device *s, struct sysdev_attribute *attr, - const char *buf,size_t siz) + const char *buf, size_t siz) { char *p; int len; + strncpy(trigger, buf, sizeof(trigger)); trigger[sizeof(trigger)-1] = 0; len = strlen(trigger); p = strchr(trigger, '\n'); - if (*p) *p = 0; + + if (*p) + *p = 0; + return len; } static SYSDEV_ATTR(trigger, 0644, show_trigger, set_trigger); static SYSDEV_INT_ATTR(tolerant, 0644, tolerant); -ACCESSOR(check_interval,check_interval,mce_restart()) + +ACCESSOR(check_interval, check_interval, mce_restart()) + static struct sysdev_attribute *mce_attributes[] = { &attr_tolerant.attr, &attr_check_interval, &attr_trigger, NULL @@ -996,7 +1042,7 @@ static struct sysdev_attribute *mce_attributes[] = { static cpumask_var_t mce_device_initialized; -/* Per cpu sysdev init. All of the cpus still share the same ctl bank */ +/* Per cpu sysdev init. All of the cpus still share the same ctrl bank: */ static __cpuinit int mce_create_device(unsigned int cpu) { int err; @@ -1006,15 +1052,15 @@ static __cpuinit int mce_create_device(unsigned int cpu) return -EIO; memset(&per_cpu(device_mce, cpu).kobj, 0, sizeof(struct kobject)); - per_cpu(device_mce,cpu).id = cpu; - per_cpu(device_mce,cpu).cls = &mce_sysclass; + per_cpu(device_mce, cpu).id = cpu; + per_cpu(device_mce, cpu).cls = &mce_sysclass; - err = sysdev_register(&per_cpu(device_mce,cpu)); + err = sysdev_register(&per_cpu(device_mce, cpu)); if (err) return err; for (i = 0; mce_attributes[i]; i++) { - err = sysdev_create_file(&per_cpu(device_mce,cpu), + err = sysdev_create_file(&per_cpu(device_mce, cpu), mce_attributes[i]); if (err) goto error; @@ -1035,10 +1081,10 @@ error2: } error: while (--i >= 0) { - sysdev_remove_file(&per_cpu(device_mce,cpu), + sysdev_remove_file(&per_cpu(device_mce, cpu), mce_attributes[i]); } - sysdev_unregister(&per_cpu(device_mce,cpu)); + sysdev_unregister(&per_cpu(device_mce, cpu)); return err; } @@ -1051,12 +1097,12 @@ static __cpuinit void mce_remove_device(unsigned int cpu) return; for (i = 0; mce_attributes[i]; i++) - sysdev_remove_file(&per_cpu(device_mce,cpu), + sysdev_remove_file(&per_cpu(device_mce, cpu), mce_attributes[i]); for (i = 0; i < banks; i++) sysdev_remove_file(&per_cpu(device_mce, cpu), &bank_attrs[i]); - sysdev_unregister(&per_cpu(device_mce,cpu)); + sysdev_unregister(&per_cpu(device_mce, cpu)); cpumask_clear_cpu(cpu, mce_device_initialized); } @@ -1076,11 +1122,12 @@ static void mce_disable_cpu(void *h) static void mce_reenable_cpu(void *h) { - int i; unsigned long action = *(unsigned long *)h; + int i; if (!mce_available(¤t_cpu_data)) return; + if (!(action & CPU_TASKS_FROZEN)) cmci_reenable(); for (i = 0; i < banks; i++) @@ -1088,8 +1135,8 @@ static void mce_reenable_cpu(void *h) } /* Get notified when a cpu comes on/off. Be hotplug friendly. */ -static int __cpuinit mce_cpu_callback(struct notifier_block *nfb, - unsigned long action, void *hcpu) +static int __cpuinit +mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; struct timer_list *t = &per_cpu(mce_timer, cpu); @@ -1142,12 +1189,14 @@ static __init int mce_init_banks(void) for (i = 0; i < banks; i++) { struct sysdev_attribute *a = &bank_attrs[i]; - a->attr.name = kasprintf(GFP_KERNEL, "bank%d", i); + + a->attr.name = kasprintf(GFP_KERNEL, "bank%d", i); if (!a->attr.name) goto nomem; - a->attr.mode = 0644; - a->show = show_bank; - a->store = set_bank; + + a->attr.mode = 0644; + a->show = show_bank; + a->store = set_bank; } return 0; @@ -1156,6 +1205,7 @@ nomem: kfree(bank_attrs[i].attr.name); kfree(bank_attrs); bank_attrs = NULL; + return -ENOMEM; } @@ -1185,6 +1235,7 @@ static __init int mce_init_device(void) register_hotcpu_notifier(&mce_cpu_notifier); misc_register(&mce_log_device); + return err; } -- 2.34.1