: i386: make x86_64 tsc header require i386 rather than vice-versa
PATCH 1/1 : i386: make x86_64 tsc header require i386 rather than vice-versa
Prior to commit 95492e4646e5de8b43d9a7908d6177fb737b61f0 ([PATCH] x86:
rewrite SMP TSC sync code), the headers in asm-i386 did not really require anything in include/asm-x86_64. This means that distributions such as fedora did not include asm-x86_64 in kernel-devel headers for i386. Ingo's commit changed that, and broke things. This is easy enough to hack around in package builds by just including asm-x86_64 on i386, but that's kind of annoying. If anything, x86_64 should depend upon i386, not the other way around.
This patch changes it so that asm-x86_64/tsc.h includes asm-i386/tsc.h, rather than vice-versa.
include/asm-i386/tsc.h +66 -1
@@ -1 +1,66 @@ -#include <asm-x86_64/tsc.h> +/* +* linux/include/asm-i386/tsc.h +* +* x86 TSC related functions +*/ +#ifndef _ASM_i386_TSC_H +#define _ASM_i386_TSC_H + +#include <asm/processor.h> + +/* +* Standard way to access the cycle counter. +*/ +typedef unsigned long long cycles_t ; + +extern unsigned int cpu_khz; +extern unsigned int tsc_khz; + +static inline cycles_t get_cycles (void ) +{ +unsigned long long ret =0 ; + +#ifndef CONFIG_X86_TSC +if (!cpu_has_tsc) +return 0 ; +#endif + +#if defined(CONFIG_X86_GENERIC ) || defined(CONFIG_X86_TSC ) +rdtscll (ret); +#endif +return ret; +} + +/* Like get_cycles, but make sure the CPU is synchronized. */ +static __always_inline cycles_t get_cycles_sync(void) +{ +unsigned long long ret; +#ifdef X86_FEATURE_SYNC_RDTSC +unsigned eax; + +/* +* Don't do an additional sync on CPUs where we know +* RDTSC is already synchronous: +*/ +alternative_io ("cpuid" ,ASM_NOP2 ,X86_FEATURE_SYNC_RDTSC , + "=a" (eax), "0" (1) : "ebx","ecx","edx","memory"); +#else +sync_core (); +#endif +rdtscll (ret); + +return ret; +} + +extern void tsc_init (void ); +extern void mark_tsc_unstable (void ); +extern int unsynchronized_tsc (void ); + +/* +* Boot-time check whether the TSCs are synchronized across +* all CPUs/cores: +*/ +extern void check_tsc_sync_source (int cpu); +extern void check_tsc_sync_target (void ); + +#endif
include/asm-x86_64/tsc.h +1 -66
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Quoted 11 lines · On Fri, 02 Mar 2007 22:10:33 -0500 Andres Salomon <[email protected]> wrote:
Prior to commit
95492e4646e5de8b43d9a7908d6177fb737b61f0([PATCH] x86:
rewrite SMP TSC sync code), the headers in asm-i386 did not really require anything ininclude/asm-x86_64. This means that distributions such as fedora did not include asm-x86_64 in kernel-devel headers for i386. Ingo's commit changed that, and broke things. This is easy enough to hack around in package builds by just including asm-x86_64 on i386, but that's kind of annoying. If anything,x86_64should depend upon i386, not the other way around.This patch changes it so that
asm-x86_64/tsc.hincludesasm-i386/tsc.h, rather than vice-versa.
Agree - I don't see any gain in making the references be bidirectional, and it just makes life more complicated. Knowing "x86_64 always references i386" is a useful mental mark.
That, plus the kernel-headers point which you describe..
<looks at early_printk.c>