Messages in this thread Patch in this message | | | Date | Mon, 4 Aug 2014 13:55:40 +0200 | From | Ingo Molnar <> | Subject | [GIT PULL] x86/cleanups for v3.17 |
| |
Linus,
Please pull the latest x86-cleanups-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-cleanups-for-linus
# HEAD: b08ee5f7e4135d64b8edd769367f8964a725122e x86: Simplify __HAVE_ARCH_CMPXCHG tests
Two cleanups.
Thanks,
Ingo
------------------> Borislav Petkov (1): x86: Simplify __HAVE_ARCH_CMPXCHG tests
Michal Nazarewicz (1): x86/tsc: Get rid of custom DIV_ROUND() macro
arch/x86/include/asm/cmpxchg.h | 4 ++-- arch/x86/include/asm/cmpxchg_32.h | 2 -- arch/x86/include/asm/cmpxchg_64.h | 2 -- arch/x86/include/asm/mc146818rtc.h | 2 +- arch/x86/include/asm/mutex_32.h | 16 ++-------------- arch/x86/kernel/acpi/boot.c | 4 ---- arch/x86/kernel/tsc.c | 7 +++---- 7 files changed, 8 insertions(+), 29 deletions(-)
diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h index d47786a..99c105d7 100644 --- a/arch/x86/include/asm/cmpxchg.h +++ b/arch/x86/include/asm/cmpxchg.h @@ -4,6 +4,8 @@ #include <linux/compiler.h> #include <asm/alternative.h> /* Provides LOCK_PREFIX */ +#define __HAVE_ARCH_CMPXCHG 1 + /* * Non-existant functions to indicate usage errors at link time * (or compile-time if the compiler implements __compiletime_error(). @@ -143,7 +145,6 @@ extern void __add_wrong_size(void) # include <asm/cmpxchg_64.h> #endif -#ifdef __HAVE_ARCH_CMPXCHG #define cmpxchg(ptr, old, new) \ __cmpxchg(ptr, old, new, sizeof(*(ptr))) @@ -152,7 +153,6 @@ extern void __add_wrong_size(void) #define cmpxchg_local(ptr, old, new) \ __cmpxchg_local(ptr, old, new, sizeof(*(ptr))) -#endif /* * xadd() adds "inc" to "*ptr" and atomically returns the previous diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h index f8bf2ee..f7e1429 100644 --- a/arch/x86/include/asm/cmpxchg_32.h +++ b/arch/x86/include/asm/cmpxchg_32.h @@ -34,8 +34,6 @@ static inline void set_64bit(volatile u64 *ptr, u64 value) : "memory"); } -#define __HAVE_ARCH_CMPXCHG 1 - #ifdef CONFIG_X86_CMPXCHG64 #define cmpxchg64(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg64((ptr), (unsigned long long)(o), \ diff --git a/arch/x86/include/asm/cmpxchg_64.h b/arch/x86/include/asm/cmpxchg_64.h index 614be87..1af9469 100644 --- a/arch/x86/include/asm/cmpxchg_64.h +++ b/arch/x86/include/asm/cmpxchg_64.h @@ -6,8 +6,6 @@ static inline void set_64bit(volatile u64 *ptr, u64 val) *ptr = val; } -#define __HAVE_ARCH_CMPXCHG 1 - #define cmpxchg64(ptr, o, n) \ ({ \ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h index a55c7ef..0f555cc 100644 --- a/arch/x86/include/asm/mc146818rtc.h +++ b/arch/x86/include/asm/mc146818rtc.h @@ -13,7 +13,7 @@ #define RTC_ALWAYS_BCD 1 /* RTC operates in binary mode */ #endif -#if defined(CONFIG_X86_32) && defined(__HAVE_ARCH_CMPXCHG) +#if defined(CONFIG_X86_32) /* * This lock provides nmi access to the CMOS/RTC registers. It has some * special properties. It is owned by a CPU and stores the index register diff --git a/arch/x86/include/asm/mutex_32.h b/arch/x86/include/asm/mutex_32.h index 0208c3c..85e6cda 100644 --- a/arch/x86/include/asm/mutex_32.h +++ b/arch/x86/include/asm/mutex_32.h @@ -100,23 +100,11 @@ do { \ static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { - /* - * We have two variants here. The cmpxchg based one is the best one - * because it never induce a false contention state. It is included - * here because architectures using the inc/dec algorithms over the - * xchg ones are much more likely to support cmpxchg natively. - * - * If not we fall back to the spinlock based variant - that is - * just as efficient (and simpler) as a 'destructive' probing of - * the mutex state would be. - */ -#ifdef __HAVE_ARCH_CMPXCHG + /* cmpxchg because it never induces a false contention state. */ if (likely(atomic_cmpxchg(count, 1, 0) == 1)) return 1; + return 0; -#else - return fail_fn(count); -#endif } #endif /* _ASM_X86_MUTEX_32_H */ diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 86281ff..a531f65 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -74,10 +74,6 @@ int acpi_fix_pin2_polarity __initdata; static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE; #endif -#ifndef __HAVE_ARCH_CMPXCHG -#warning ACPI uses CMPXCHG, i486 and later hardware -#endif - /* -------------------------------------------------------------------------- Boot-time Configuration -------------------------------------------------------------------------- */ diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 57e5ce1..8764232 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -234,9 +234,6 @@ static inline unsigned long long cycles_2_ns(unsigned long long cyc) return ns; } -/* XXX surely we already have this someplace in the kernel?! */ -#define DIV_ROUND(n, d) (((n) + ((d) / 2)) / (d)) - static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) { unsigned long long tsc_now, ns_now; @@ -259,7 +256,9 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) * time function is continuous; see the comment near struct * cyc2ns_data. */ - data->cyc2ns_mul = DIV_ROUND(NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR, cpu_khz); + data->cyc2ns_mul = + DIV_ROUND_CLOSEST(NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR, + cpu_khz); data->cyc2ns_shift = CYC2NS_SCALE_FACTOR; data->cyc2ns_offset = ns_now - mul_u64_u32_shr(tsc_now, data->cyc2ns_mul, CYC2NS_SCALE_FACTOR);
| |