mce, edac: Use an atomic notifier for MCEs decoding

Add an atomic notifier which ensures proper locking when conveying
MCE info to EDAC for decoding. The actual notifier call overrides a
default, negative priority notifier.

Note: make sure we register the default decoder only once since
mcheck_init() runs on each CPU.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20091003065752.GA8935@liondog.tnic>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Borislav Petkov 2009-10-07 13:20:38 +02:00 committed by Ingo Molnar
parent d93a8f829f
commit fb2531953f
3 changed files with 34 additions and 19 deletions

View File

@ -108,6 +108,8 @@ struct mce_log {
#define K8_MCE_THRESHOLD_BANK_5 (MCE_THRESHOLD_BASE + 5 * 9)
#define K8_MCE_THRESHOLD_DRAM_ECC (MCE_THRESHOLD_BANK_4 + 0)
extern struct atomic_notifier_head x86_mce_decoder_chain;
#ifdef __KERNEL__
#include <linux/percpu.h>
@ -213,6 +215,5 @@ extern void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
void intel_init_thermal(struct cpuinfo_x86 *c);
void mce_log_therm_throt_event(__u64 status);
#endif /* __KERNEL__ */
#endif /* _ASM_X86_MCE_H */

View File

@ -85,18 +85,26 @@ static DECLARE_WAIT_QUEUE_HEAD(mce_wait);
static DEFINE_PER_CPU(struct mce, mces_seen);
static int cpu_missing;
static void default_decode_mce(struct mce *m)
/*
* CPU/chipset specific EDAC code can register a notifier call here to print
* MCE errors in a human-readable form.
*/
ATOMIC_NOTIFIER_HEAD(x86_mce_decoder_chain);
EXPORT_SYMBOL_GPL(x86_mce_decoder_chain);
static int default_decode_mce(struct notifier_block *nb, unsigned long val,
void *data)
{
pr_emerg("No human readable MCE decoding support on this CPU type.\n");
pr_emerg("Run the message through 'mcelog --ascii' to decode.\n");
return NOTIFY_STOP;
}
/*
* CPU/chipset specific EDAC code can register a callback here to print
* MCE errors in a human-readable form:
*/
void (*x86_mce_decode_callback)(struct mce *m) = default_decode_mce;
EXPORT_SYMBOL(x86_mce_decode_callback);
static struct notifier_block mce_dec_nb = {
.notifier_call = default_decode_mce,
.priority = -1,
};
/* MCA banks polled by the period polling timer for corrected events */
DEFINE_PER_CPU(mce_banks_t, mce_poll_banks) = {
@ -204,9 +212,9 @@ static void print_mce(struct mce *m)
/*
* Print out human-readable details about the MCE error,
* (if the CPU has an implementation for that):
* (if the CPU has an implementation for that)
*/
x86_mce_decode_callback(m);
atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, m);
}
static void print_mce_head(void)
@ -1420,6 +1428,9 @@ void __cpuinit mcheck_init(struct cpuinfo_x86 *c)
mce_cpu_features(c);
mce_init_timer();
INIT_WORK(&__get_cpu_var(mce_work), mce_process_work);
if (raw_smp_processor_id() == 0)
atomic_notifier_chain_register(&x86_mce_decoder_chain, &mce_dec_nb);
}
/*

View File

@ -3,7 +3,6 @@
static bool report_gart_errors;
static void (*nb_bus_decoder)(int node_id, struct err_regs *regs);
static void (*orig_mce_callback)(struct mce *m);
void amd_report_gart_errors(bool v)
{
@ -363,8 +362,10 @@ static inline void amd_decode_err_code(unsigned int ec)
pr_warning("Huh? Unknown MCE error 0x%x\n", ec);
}
static void amd_decode_mce(struct mce *m)
static int amd_decode_mce(struct notifier_block *nb, unsigned long val,
void *data)
{
struct mce *m = (struct mce *)data;
struct err_regs regs;
int node, ecc;
@ -420,20 +421,22 @@ static void amd_decode_mce(struct mce *m)
}
amd_decode_err_code(m->status & 0xffff);
return NOTIFY_STOP;
}
static struct notifier_block amd_mce_dec_nb = {
.notifier_call = amd_decode_mce,
};
static int __init mce_amd_init(void)
{
/*
* We can decode MCEs for Opteron and later CPUs:
*/
if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) &&
(boot_cpu_data.x86 >= 0xf)) {
/* safe the default decode mce callback */
orig_mce_callback = x86_mce_decode_callback;
x86_mce_decode_callback = amd_decode_mce;
}
(boot_cpu_data.x86 >= 0xf))
atomic_notifier_chain_register(&x86_mce_decoder_chain, &amd_mce_dec_nb);
return 0;
}
@ -442,7 +445,7 @@ early_initcall(mce_amd_init);
#ifdef MODULE
static void __exit mce_amd_exit(void)
{
x86_mce_decode_callback = orig_mce_callback;
atomic_notifier_chain_unregister(&x86_mce_decoder_chain, &amd_mce_dec_nb);
}
MODULE_DESCRIPTION("AMD MCE decoder");