diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:20:03 +0200 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:20:03 +0200 |
commit | 96a388de5dc53a8b234b3fd41f3ae2cedc9ffd42 (patch) | |
tree | d947a467aa2da3140279617bc4b9b101640d7bf4 /include/asm-x86/tsc.h | |
parent | 27bd0c955648646abf2a353a8371d28c37bcd982 (diff) |
i386/x86_64: move headers to include/asm-x86
Move the headers to include/asm-x86 and fixup the
header install make rules
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/tsc.h')
-rw-r--r-- | include/asm-x86/tsc.h | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/include/asm-x86/tsc.h b/include/asm-x86/tsc.h new file mode 100644 index 000000000000..a4d806610b7f --- /dev/null +++ b/include/asm-x86/tsc.h @@ -0,0 +1,75 @@ +/* + * linux/include/asm-i386/tsc.h + * + * i386 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; + unsigned eax, edx; + + /* + * Use RDTSCP if possible; it is guaranteed to be synchronous + * and doesn't cause a VMEXIT on Hypervisors + */ + alternative_io(ASM_NOP3, ".byte 0x0f,0x01,0xf9", X86_FEATURE_RDTSCP, + ASM_OUTPUT2("=a" (eax), "=d" (edx)), + "a" (0U), "d" (0U) : "ecx", "memory"); + ret = (((unsigned long long)edx) << 32) | ((unsigned long long)eax); + if (ret) + return ret; + + /* + * 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"); + rdtscll(ret); + + return ret; +} + +extern void tsc_init(void); +extern void mark_tsc_unstable(char *reason); +extern int unsynchronized_tsc(void); +extern void init_tsc_clocksource(void); +int check_tsc_unstable(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 |