Commit 817f32d0 authored by Andi Kleen's avatar Andi Kleen Committed by H. Peter Anvin
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x86, mce: add table driven machine check grading 



The machine check grading (as in deciding what should be done for a given
register value) has to be done multiple times soon and it's also getting
more complicated.
So it makes sense to consolidate it into a single function. To get smaller
and more straight forward and possibly more extensible code I opted towards
a new table driven method. The various rules are put into a table
when is then executed by a very simple interpreter.

The grading engine is in a new file mce-severity.c. I also added a private
include file mce-internal.h, because mce.h is already a bit too cluttered.

This is dead code right now, but will be used in followon patches.

Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Signed-off-by: default avatarHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
parent a0189c70

arch/x86/kernel/cpu/mcheck/Makefile

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obj-y				=  mce.o therm_throt.o



obj-$(CONFIG_X86_NEW_MCE)	+= mce-severity.o

obj-$(CONFIG_X86_OLD_MCE)	+= k7.o p4.o p6.o

obj-$(CONFIG_X86_ANCIENT_MCE)	+= winchip.o p5.o

obj-$(CONFIG_X86_MCE_P4THERMAL)	+= mce_intel.o

arch/x86/kernel/cpu/mcheck/mce-internal.h

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#include <asm/mce.h>



enum severity_level {

	MCE_NO_SEVERITY,

	MCE_SOME_SEVERITY,

	MCE_UC_SEVERITY,

	MCE_PANIC_SEVERITY,

};



int mce_severity(struct mce *a, int tolerant, char **msg);

arch/x86/kernel/cpu/mcheck/mce-severity.c

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Original line number Diff line number Diff line 
/*

 * MCE grading rules.

 * Copyright 2008, 2009 Intel Corporation.

 *

 * 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; version 2

 * of the License.

 *

 * Author: Andi Kleen

 */

#include <linux/kernel.h>

#include <asm/mce.h>



#include "mce-internal.h"



/*

 * Grade an mce by severity. In general the most severe ones are processed

 * first. Since there are quite a lot of combinations test the bits in a

 * table-driven way. The rules are simply processed in order, first

 * match wins.

 */



static struct severity {

	u64 mask;

	u64 result;

	unsigned char sev;

	unsigned char mcgmask;

	unsigned char mcgres;

	char *msg;

} severities[] = {

#define SEV(s) .sev = MCE_ ## s ## _SEVERITY

#define BITCLR(x, s, m, r...) { .mask = x, .result = 0, SEV(s), .msg = m, ## r }

#define BITSET(x, s, m, r...) { .mask = x, .result = x, SEV(s), .msg = m, ## r }

#define MCGMASK(x, res, s, m, r...) \

	{ .mcgmask = x, .mcgres = res, SEV(s), .msg = m, ## r }

	BITCLR(MCI_STATUS_VAL, NO, "Invalid"),

	BITCLR(MCI_STATUS_EN, NO, "Not enabled"),

	BITSET(MCI_STATUS_PCC, PANIC, "Processor context corrupt"),

	MCGMASK(MCG_STATUS_RIPV, 0, PANIC, "No restart IP"),

	BITSET(MCI_STATUS_UC|MCI_STATUS_OVER, PANIC, "Overflowed uncorrected"),

	BITSET(MCI_STATUS_UC, UC, "Uncorrected"),

	BITSET(0, SOME, "No match")	/* always matches. keep at end */

};



int mce_severity(struct mce *a, int tolerant, char **msg)

{

	struct severity *s;

	for (s = severities;; s++) {

		if ((a->status & s->mask) != s->result)

			continue;

		if ((a->mcgstatus & s->mcgmask) != s->mcgres)

			continue;

		if (s->sev > MCE_NO_SEVERITY && (a->status & MCI_STATUS_UC) &&

			tolerant < 1)

			return MCE_PANIC_SEVERITY;

		if (msg)

			*msg = s->msg;

		return s->sev;

	}

}

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