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| author | Andy Lutomirski <luto@amacapital.net> | 2014-10-30 14:58:01 -0700 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2014-11-03 13:41:53 +0100 |
| commit | e76b027e6408f5570dc940b731ec9ae870c6188a (patch) | |
| tree | d94287f98ee13c7e2fedd4890499f178079ce6ab /arch/x86/include/asm/vsyscall.h | |
| parent | a92f101bc99d17b75021cf29f18cc57f39a37d1f (diff) | |
| download | linux-0-day-e76b027e6408f5570dc940b731ec9ae870c6188a.tar.gz linux-0-day-e76b027e6408f5570dc940b731ec9ae870c6188a.tar.xz | |
x86,vdso: Use LSL unconditionally for vgetcpu
LSL is faster than RDTSCP and works everywhere; there's no need to
switch between them depending on CPU.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Andi Kleen <andi@firstfloor.org>
Link: http://lkml.kernel.org/r/72f73d5ec4514e02bba345b9759177ef03742efb.1414706021.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/include/asm/vsyscall.h')
| -rw-r--r-- | arch/x86/include/asm/vsyscall.h | 29 |
1 files changed, 0 insertions, 29 deletions
diff --git a/arch/x86/include/asm/vsyscall.h b/arch/x86/include/asm/vsyscall.h index 2a46ca720afca..34f7d8857542c 100644 --- a/arch/x86/include/asm/vsyscall.h +++ b/arch/x86/include/asm/vsyscall.h @@ -4,15 +4,6 @@ #include <linux/seqlock.h> #include <uapi/asm/vsyscall.h> -#define VGETCPU_RDTSCP 1 -#define VGETCPU_LSL 2 - -/* kernel space (writeable) */ -extern int vgetcpu_mode; -extern struct timezone sys_tz; - -#include <asm/vvar.h> - extern void map_vsyscall(void); /* @@ -21,24 +12,4 @@ extern void map_vsyscall(void); */ extern bool emulate_vsyscall(struct pt_regs *regs, unsigned long address); -#ifdef CONFIG_X86_64 - -#define VGETCPU_CPU_MASK 0xfff - -static inline unsigned int __getcpu(void) -{ - unsigned int p; - - if (VVAR(vgetcpu_mode) == VGETCPU_RDTSCP) { - /* Load per CPU data from RDTSCP */ - native_read_tscp(&p); - } else { - /* Load per CPU data from GDT */ - asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG)); - } - - return p; -} -#endif /* CONFIG_X86_64 */ - #endif /* _ASM_X86_VSYSCALL_H */ |