From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752808AbXCYMS3 (ORCPT ); Sun, 25 Mar 2007 08:18:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753348AbXCYMS2 (ORCPT ); Sun, 25 Mar 2007 08:18:28 -0400 Received: from smtp-100-sunday.noc.nerim.net ([62.4.17.100]:1468 "EHLO mallaury.nerim.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752808AbXCYMS1 (ORCPT ); Sun, 25 Mar 2007 08:18:27 -0400 Date: Sun, 25 Mar 2007 14:18:23 +0200 From: Jean Delvare To: LKML , Andrew Morton Cc: Rudolf Marek , Alexey Dobriyan , Dave Jones Subject: [PATCH 1/2] MSR: Add support for safe variants Message-Id: <20070325141823.c0e9c4c7.khali@linux-fr.org> X-Mailer: Sylpheed version 2.2.10 (GTK+ 2.8.20; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Rudolf Marek Add support for _safe (exception handled) variants of rdmsr_on_cpu and wrmsr_on_cpu. This is needed for the upcoming coretemp hardware monitoring driver, which might step into non-existing (poorly documented) MSR. Signed-off-by: Rudolf Marek Cc: Alexey Dobriyan Cc: Dave Jones Signed-off-by: Jean Delvare --- Andrew, can you please pick this patch? I don't want to keep it in my hwmon tree, as it might useful for others as well. arch/i386/lib/msr-on-cpu.c | 71 ++++++++++++++++++++++++++++++++++++++++---- include/asm-i386/msr.h | 12 +++++++ include/asm-x86_64/msr.h | 11 +++++++ 3 files changed, 87 insertions(+), 7 deletions(-) --- linux-2.6.21-rc4.orig/arch/i386/lib/msr-on-cpu.c 2007-02-28 09:48:18.000000000 +0100 +++ linux-2.6.21-rc4/arch/i386/lib/msr-on-cpu.c 2007-03-24 20:50:05.000000000 +0100 @@ -6,6 +6,7 @@ struct msr_info { u32 msr_no; u32 l, h; + int err; }; static void __rdmsr_on_cpu(void *info) @@ -15,20 +16,38 @@ static void __rdmsr_on_cpu(void *info) rdmsr(rv->msr_no, rv->l, rv->h); } -void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) +static void __rdmsr_safe_on_cpu(void *info) { + struct msr_info *rv = info; + + rv->err = rdmsr_safe(rv->msr_no, &rv->l, &rv->h); +} + +static int _rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h, int safe) +{ + int err = 0; preempt_disable(); if (smp_processor_id() == cpu) - rdmsr(msr_no, *l, *h); + if (safe) + err = rdmsr_safe(msr_no, l, h); + else + rdmsr(msr_no, *l, *h); else { struct msr_info rv; rv.msr_no = msr_no; - smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 0, 1); + if (safe) { + smp_call_function_single(cpu, __rdmsr_safe_on_cpu, + &rv, 0, 1); + err = rv.err; + } else { + smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 0, 1); + } *l = rv.l; *h = rv.h; } preempt_enable(); + return err; } static void __wrmsr_on_cpu(void *info) @@ -38,21 +57,61 @@ static void __wrmsr_on_cpu(void *info) wrmsr(rv->msr_no, rv->l, rv->h); } -void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) +static void __wrmsr_safe_on_cpu(void *info) { + struct msr_info *rv = info; + + rv->err = wrmsr_safe(rv->msr_no, rv->l, rv->h); +} + +static int _wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h, int safe) +{ + int err = 0; preempt_disable(); if (smp_processor_id() == cpu) - wrmsr(msr_no, l, h); + if (safe) + err = wrmsr_safe(msr_no, l, h); + else + wrmsr(msr_no, l, h); else { struct msr_info rv; rv.msr_no = msr_no; rv.l = l; rv.h = h; - smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 0, 1); + if (safe) { + smp_call_function_single(cpu, __wrmsr_safe_on_cpu, + &rv, 0, 1); + err = rv.err; + } else { + smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 0, 1); + } } preempt_enable(); + return err; +} + +void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) +{ + _wrmsr_on_cpu(cpu, msr_no, l, h, 0); +} + +void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) +{ + _rdmsr_on_cpu(cpu, msr_no, l, h, 0); +} + +int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) +{ + return _wrmsr_on_cpu(cpu, msr_no, l, h, 1); +} + +int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) +{ + return _rdmsr_on_cpu(cpu, msr_no, l, h, 1); } EXPORT_SYMBOL(rdmsr_on_cpu); EXPORT_SYMBOL(wrmsr_on_cpu); +EXPORT_SYMBOL(rdmsr_safe_on_cpu); +EXPORT_SYMBOL(wrmsr_safe_on_cpu); --- linux-2.6.21-rc4.orig/include/asm-i386/msr.h 2007-02-28 09:48:21.000000000 +0100 +++ linux-2.6.21-rc4/include/asm-i386/msr.h 2007-03-24 20:50:05.000000000 +0100 @@ -4,7 +4,7 @@ #ifdef CONFIG_PARAVIRT #include #else - +#include /* * Access to machine-specific registers (available on 586 and better only) * Note: the rd* operations modify the parameters directly (without using @@ -86,6 +86,8 @@ static inline void wrmsrl (unsigned long #ifdef CONFIG_SMP void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); +int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); +int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); #else /* CONFIG_SMP */ static inline void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) { @@ -95,6 +97,14 @@ static inline void wrmsr_on_cpu(unsigned { wrmsr(msr_no, l, h); } +static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) +{ + return rdmsr_safe(msr_no, l, h); +} +static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) +{ + return wrmsr_safe(msr_no, l, h); +} #endif /* CONFIG_SMP */ /* symbolic names for some interesting MSRs */ --- linux-2.6.21-rc4.orig/include/asm-x86_64/msr.h 2007-02-28 09:48:21.000000000 +0100 +++ linux-2.6.21-rc4/include/asm-x86_64/msr.h 2007-03-24 20:50:05.000000000 +0100 @@ -2,6 +2,7 @@ #define X86_64_MSR_H 1 #ifndef __ASSEMBLY__ +#include /* * Access to machine-specific registers (available on 586 and better only) * Note: the rd* operations modify the parameters directly (without using @@ -163,6 +164,8 @@ static inline unsigned int cpuid_edx(uns #ifdef CONFIG_SMP void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); +int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); +int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); #else /* CONFIG_SMP */ static inline void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) { @@ -172,6 +175,14 @@ static inline void wrmsr_on_cpu(unsigned { wrmsr(msr_no, l, h); } +static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) +{ + return rdmsr_safe(msr_no, l, h); +} +static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) +{ + return wrmsr_safe(msr_no, l, h); +} #endif /* CONFIG_SMP */ #endif -- Jean Delvare