Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753443AbYHRKdh (ORCPT ); Mon, 18 Aug 2008 06:33:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751977AbYHRKd1 (ORCPT ); Mon, 18 Aug 2008 06:33:27 -0400 Received: from mail.free-electrons.com ([88.191.46.45]:41821 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751713AbYHRKd0 (ORCPT ); Mon, 18 Aug 2008 06:33:26 -0400 From: Thomas Petazzoni To: mingo@elte.hu Cc: linux-kernel@vger.kernel.org, linux-embedded@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, michael@free-electrons.com, thomas.petazzoni@free-electrons.com Subject: [PATCH] [x86] Move cmpxchg fallbacks to a generic place Date: Mon, 18 Aug 2008 12:33:21 +0200 Message-Id: <1219055602-8046-2-git-send-email-thomas.petazzoni@free-electrons.com> X-Mailer: git-send-email 1.5.4.3 In-Reply-To: <> References: <> In-Reply-To: <20080815143843.GA519@elte.hu> References: <20080815143843.GA519@elte.hu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5120 Lines: 192 arch/x86/kernel/cpu/intel.c defines a few fallback functions (cmpxchg_*()) that are used when the CPU doesn't support cmpxchg and/or cmpxchg64 natively. However, while defined in an Intel-specific file, these functions are also used for CPUs from other vendors when they don't support cmpxchg and/or cmpxchg64. This breaks the compilation when support for Intel CPUs is disabled. This patch moves these functions to a new arch/x86/kernel/cpu/cmpxchg.c file, unconditionally compiled when X86_32 is enabled. Signed-off-by: Thomas Petazzoni --- arch/x86/kernel/cpu/Makefile | 2 +- arch/x86/kernel/cpu/cmpxchg.c | 72 +++++++++++++++++++++++++++++++++++++++++ arch/x86/kernel/cpu/intel.c | 64 ------------------------------------ 3 files changed, 73 insertions(+), 65 deletions(-) create mode 100644 arch/x86/kernel/cpu/cmpxchg.c diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index a35ee92..a0fc6c1 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -5,7 +5,7 @@ obj-y := intel_cacheinfo.o addon_cpuid_features.o obj-y += proc.o feature_names.o -obj-$(CONFIG_X86_32) += common.o bugs.o +obj-$(CONFIG_X86_32) += common.o bugs.o cmpxchg.o obj-$(CONFIG_X86_64) += common_64.o bugs_64.o obj-$(CONFIG_CPU_SUP_AMD_32) += amd.o diff --git a/arch/x86/kernel/cpu/cmpxchg.c b/arch/x86/kernel/cpu/cmpxchg.c new file mode 100644 index 0000000..2056ccf --- /dev/null +++ b/arch/x86/kernel/cpu/cmpxchg.c @@ -0,0 +1,72 @@ +/* + * cmpxchg*() fallbacks for CPU not supporting these instructions + */ + +#include +#include +#include + +#ifndef CONFIG_X86_CMPXCHG +unsigned long cmpxchg_386_u8(volatile void *ptr, u8 old, u8 new) +{ + u8 prev; + unsigned long flags; + + /* Poor man's cmpxchg for 386. Unsuitable for SMP */ + local_irq_save(flags); + prev = *(u8 *)ptr; + if (prev == old) + *(u8 *)ptr = new; + local_irq_restore(flags); + return prev; +} +EXPORT_SYMBOL(cmpxchg_386_u8); + +unsigned long cmpxchg_386_u16(volatile void *ptr, u16 old, u16 new) +{ + u16 prev; + unsigned long flags; + + /* Poor man's cmpxchg for 386. Unsuitable for SMP */ + local_irq_save(flags); + prev = *(u16 *)ptr; + if (prev == old) + *(u16 *)ptr = new; + local_irq_restore(flags); + return prev; +} +EXPORT_SYMBOL(cmpxchg_386_u16); + +unsigned long cmpxchg_386_u32(volatile void *ptr, u32 old, u32 new) +{ + u32 prev; + unsigned long flags; + + /* Poor man's cmpxchg for 386. Unsuitable for SMP */ + local_irq_save(flags); + prev = *(u32 *)ptr; + if (prev == old) + *(u32 *)ptr = new; + local_irq_restore(flags); + return prev; +} +EXPORT_SYMBOL(cmpxchg_386_u32); +#endif + +#ifndef CONFIG_X86_CMPXCHG64 +unsigned long long cmpxchg_486_u64(volatile void *ptr, u64 old, u64 new) +{ + u64 prev; + unsigned long flags; + + /* Poor man's cmpxchg8b for 386 and 486. Unsuitable for SMP */ + local_irq_save(flags); + prev = *(u64 *)ptr; + if (prev == old) + *(u64 *)ptr = new; + local_irq_restore(flags); + return prev; +} +EXPORT_SYMBOL(cmpxchg_486_u64); +#endif + diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 5c8959b..77618c7 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -307,69 +307,5 @@ static struct cpu_dev intel_cpu_dev __cpuinitdata = { cpu_vendor_dev_register(X86_VENDOR_INTEL, &intel_cpu_dev); -#ifndef CONFIG_X86_CMPXCHG -unsigned long cmpxchg_386_u8(volatile void *ptr, u8 old, u8 new) -{ - u8 prev; - unsigned long flags; - - /* Poor man's cmpxchg for 386. Unsuitable for SMP */ - local_irq_save(flags); - prev = *(u8 *)ptr; - if (prev == old) - *(u8 *)ptr = new; - local_irq_restore(flags); - return prev; -} -EXPORT_SYMBOL(cmpxchg_386_u8); - -unsigned long cmpxchg_386_u16(volatile void *ptr, u16 old, u16 new) -{ - u16 prev; - unsigned long flags; - - /* Poor man's cmpxchg for 386. Unsuitable for SMP */ - local_irq_save(flags); - prev = *(u16 *)ptr; - if (prev == old) - *(u16 *)ptr = new; - local_irq_restore(flags); - return prev; -} -EXPORT_SYMBOL(cmpxchg_386_u16); - -unsigned long cmpxchg_386_u32(volatile void *ptr, u32 old, u32 new) -{ - u32 prev; - unsigned long flags; - - /* Poor man's cmpxchg for 386. Unsuitable for SMP */ - local_irq_save(flags); - prev = *(u32 *)ptr; - if (prev == old) - *(u32 *)ptr = new; - local_irq_restore(flags); - return prev; -} -EXPORT_SYMBOL(cmpxchg_386_u32); -#endif - -#ifndef CONFIG_X86_CMPXCHG64 -unsigned long long cmpxchg_486_u64(volatile void *ptr, u64 old, u64 new) -{ - u64 prev; - unsigned long flags; - - /* Poor man's cmpxchg8b for 386 and 486. Unsuitable for SMP */ - local_irq_save(flags); - prev = *(u64 *)ptr; - if (prev == old) - *(u64 *)ptr = new; - local_irq_restore(flags); - return prev; -} -EXPORT_SYMBOL(cmpxchg_486_u64); -#endif - /* arch_initcall(intel_cpu_init); */ -- 1.5.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/