From c08c820508233b424deab3302bc404bbecc6493a Mon Sep 17 00:00:00 2001 From: Vojtech Pavlik Date: Tue, 26 Sep 2006 10:52:28 +0200 Subject: [PATCH] Add the vgetcpu vsyscall This patch adds a vgetcpu vsyscall, which depending on the CPU RDTSCP capability uses either the RDTSCP or CPUID to obtain a CPU and node numbers and pass them to the program. AK: Lots of changes over Vojtech's original code: Better prototype for vgetcpu() It's better to pass the cpu / node numbers as separate arguments to avoid mistakes when going from SMP to NUMA. Also add a fast time stamp based cache using a user supplied argument to speed things more up. Use fast method from Chuck Ebbert to retrieve node/cpu from GDT limit instead of CPUID Made sure RDTSCP init is always executed after node is known. Drop printk Signed-off-by: Vojtech Pavlik Signed-off-by: Andi Kleen --- include/asm-x86_64/vsyscall.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/asm-x86_64/vsyscall.h') diff --git a/include/asm-x86_64/vsyscall.h b/include/asm-x86_64/vsyscall.h index 146b24402a5f..2281e9399b96 100644 --- a/include/asm-x86_64/vsyscall.h +++ b/include/asm-x86_64/vsyscall.h @@ -4,6 +4,7 @@ enum vsyscall_num { __NR_vgettimeofday, __NR_vtime, + __NR_vgetcpu, }; #define VSYSCALL_START (-10UL << 20) @@ -15,6 +16,7 @@ enum vsyscall_num { #include #define __section_vxtime __attribute__ ((unused, __section__ (".vxtime"), aligned(16))) +#define __section_vgetcpu_mode __attribute__ ((unused, __section__ (".vgetcpu_mode"), aligned(16))) #define __section_wall_jiffies __attribute__ ((unused, __section__ (".wall_jiffies"), aligned(16))) #define __section_jiffies __attribute__ ((unused, __section__ (".jiffies"), aligned(16))) #define __section_sys_tz __attribute__ ((unused, __section__ (".sys_tz"), aligned(16))) @@ -26,6 +28,9 @@ enum vsyscall_num { #define VXTIME_HPET 2 #define VXTIME_PMTMR 3 +#define VGETCPU_RDTSCP 1 +#define VGETCPU_LSL 2 + struct vxtime_data { long hpet_address; /* HPET base address */ int last; @@ -40,6 +45,7 @@ struct vxtime_data { /* vsyscall space (readonly) */ extern struct vxtime_data __vxtime; +extern int __vgetcpu_mode; extern struct timespec __xtime; extern volatile unsigned long __jiffies; extern unsigned long __wall_jiffies; @@ -48,6 +54,7 @@ extern seqlock_t __xtime_lock; /* kernel space (writeable) */ extern struct vxtime_data vxtime; +extern int vgetcpu_mode; extern unsigned long wall_jiffies; extern struct timezone sys_tz; extern int sysctl_vsyscall; @@ -55,6 +62,8 @@ extern seqlock_t xtime_lock; extern int sysctl_vsyscall; +extern void vsyscall_set_cpu(int cpu); + #define ARCH_HAVE_XTIME_LOCK 1 #endif /* __KERNEL__ */ -- cgit v1.2.1