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-rw-r--r--arch/x86/Makefile9
-rw-r--r--arch/x86/boot/code16gcc.h24
-rw-r--r--arch/x86/include/asm/cmpxchg.h4
-rw-r--r--arch/x86/include/asm/cmpxchg_32.h2
-rw-r--r--arch/x86/include/asm/cmpxchg_64.h2
-rw-r--r--arch/x86/include/asm/mc146818rtc.h2
-rw-r--r--arch/x86/include/asm/mutex_32.h16
-rw-r--r--arch/x86/kernel/acpi/boot.c4
-rw-r--r--arch/x86/kernel/entry_64.S52
-rw-r--r--arch/x86/kernel/tsc.c7
10 files changed, 47 insertions, 75 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 33f71b0..c65fd96 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -15,12 +15,9 @@ endif
# that way we can complain to the user if the CPU is insufficient.
#
# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For
-# older versions of GCC, we need to play evil and unreliable tricks to
-# attempt to ensure that our asm(".code16gcc") is first in the asm
-# output.
-CODE16GCC_CFLAGS := -m32 -include $(srctree)/arch/x86/boot/code16gcc.h \
- $(call cc-option, -fno-toplevel-reorder,\
- $(call cc-option, -fno-unit-at-a-time))
+# older versions of GCC, include an *assembly* header to make sure that
+# gcc doesn't play any games behind our back.
+CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
M16_CFLAGS := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -D__KERNEL__ \
diff --git a/arch/x86/boot/code16gcc.h b/arch/x86/boot/code16gcc.h
index d93e480..5ff4265 100644
--- a/arch/x86/boot/code16gcc.h
+++ b/arch/x86/boot/code16gcc.h
@@ -1,15 +1,11 @@
-/*
- * code16gcc.h
- *
- * This file is -include'd when compiling 16-bit C code.
- * Note: this asm() needs to be emitted before gcc emits any code.
- * Depending on gcc version, this requires -fno-unit-at-a-time or
- * -fno-toplevel-reorder.
- *
- * Hopefully gcc will eventually have a real -m16 option so we can
- * drop this hack long term.
- */
+#
+# code16gcc.h
+#
+# This file is added to the assembler via -Wa when compiling 16-bit C code.
+# This is done this way instead via asm() to make sure gcc does not reorder
+# things around us.
+#
+# gcc 4.9+ has a real -m16 option so we can drop this hack long term.
+#
-#ifndef __ASSEMBLY__
-asm(".code16gcc");
-#endif
+ .code16gcc
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/entry_64.S b/arch/x86/kernel/entry_64.S
index c844f08..2fac134 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -207,7 +207,6 @@ ENDPROC(native_usergs_sysret64)
*/
.macro XCPT_FRAME start=1 offset=0
INTR_FRAME \start, RIP+\offset-ORIG_RAX
- /*CFI_REL_OFFSET orig_rax, ORIG_RAX-ORIG_RAX*/
.endm
/*
@@ -287,21 +286,21 @@ ENDPROC(native_usergs_sysret64)
ENTRY(save_paranoid)
XCPT_FRAME 1 RDI+8
cld
- movq_cfi rdi, RDI+8
- movq_cfi rsi, RSI+8
+ movq %rdi, RDI+8(%rsp)
+ movq %rsi, RSI+8(%rsp)
movq_cfi rdx, RDX+8
movq_cfi rcx, RCX+8
movq_cfi rax, RAX+8
- movq_cfi r8, R8+8
- movq_cfi r9, R9+8
- movq_cfi r10, R10+8
- movq_cfi r11, R11+8
+ movq %r8, R8+8(%rsp)
+ movq %r9, R9+8(%rsp)
+ movq %r10, R10+8(%rsp)
+ movq %r11, R11+8(%rsp)
movq_cfi rbx, RBX+8
- movq_cfi rbp, RBP+8
- movq_cfi r12, R12+8
- movq_cfi r13, R13+8
- movq_cfi r14, R14+8
- movq_cfi r15, R15+8
+ movq %rbp, RBP+8(%rsp)
+ movq %r12, R12+8(%rsp)
+ movq %r13, R13+8(%rsp)
+ movq %r14, R14+8(%rsp)
+ movq %r15, R15+8(%rsp)
movl $1,%ebx
movl $MSR_GS_BASE,%ecx
rdmsr
@@ -1387,21 +1386,21 @@ ENTRY(error_entry)
CFI_ADJUST_CFA_OFFSET 15*8
/* oldrax contains error code */
cld
- movq_cfi rdi, RDI+8
- movq_cfi rsi, RSI+8
- movq_cfi rdx, RDX+8
- movq_cfi rcx, RCX+8
- movq_cfi rax, RAX+8
- movq_cfi r8, R8+8
- movq_cfi r9, R9+8
- movq_cfi r10, R10+8
- movq_cfi r11, R11+8
+ movq %rdi, RDI+8(%rsp)
+ movq %rsi, RSI+8(%rsp)
+ movq %rdx, RDX+8(%rsp)
+ movq %rcx, RCX+8(%rsp)
+ movq %rax, RAX+8(%rsp)
+ movq %r8, R8+8(%rsp)
+ movq %r9, R9+8(%rsp)
+ movq %r10, R10+8(%rsp)
+ movq %r11, R11+8(%rsp)
movq_cfi rbx, RBX+8
- movq_cfi rbp, RBP+8
- movq_cfi r12, R12+8
- movq_cfi r13, R13+8
- movq_cfi r14, R14+8
- movq_cfi r15, R15+8
+ movq %rbp, RBP+8(%rsp)
+ movq %r12, R12+8(%rsp)
+ movq %r13, R13+8(%rsp)
+ movq %r14, R14+8(%rsp)
+ movq %r15, R15+8(%rsp)
xorl %ebx,%ebx
testl $3,CS+8(%rsp)
je error_kernelspace
@@ -1419,6 +1418,7 @@ error_sti:
* compat mode. Check for these here too.
*/
error_kernelspace:
+ CFI_REL_OFFSET rcx, RCX+8
incl %ebx
leaq native_irq_return_iret(%rip),%rcx
cmpq %rcx,RIP+8(%rsp)
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index ea03031..56b0c33 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);