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/segment.h | 5 +++-- include/asm-x86_64/smp.h | 12 +++++++++--- include/asm-x86_64/vsyscall.h | 9 +++++++++ 3 files changed, 21 insertions(+), 5 deletions(-) (limited to 'include/asm-x86_64') diff --git a/include/asm-x86_64/segment.h b/include/asm-x86_64/segment.h index d4bed33fb32..334ddcdd8f9 100644 --- a/include/asm-x86_64/segment.h +++ b/include/asm-x86_64/segment.h @@ -20,15 +20,16 @@ #define __USER_CS 0x33 /* 6*8+3 */ #define __USER32_DS __USER_DS -#define GDT_ENTRY_TLS 1 #define GDT_ENTRY_TSS 8 /* needs two entries */ #define GDT_ENTRY_LDT 10 /* needs two entries */ #define GDT_ENTRY_TLS_MIN 12 #define GDT_ENTRY_TLS_MAX 14 -/* 15 free */ #define GDT_ENTRY_TLS_ENTRIES 3 +#define GDT_ENTRY_PER_CPU 15 /* Abused to load per CPU data from limit */ +#define __PER_CPU_SEG (GDT_ENTRY_PER_CPU * 8 + 3) + /* TLS indexes for 64bit - hardcoded in arch_prctl */ #define FS_TLS 0 #define GS_TLS 1 diff --git a/include/asm-x86_64/smp.h b/include/asm-x86_64/smp.h index 6805e1feb30..d61547fd833 100644 --- a/include/asm-x86_64/smp.h +++ b/include/asm-x86_64/smp.h @@ -133,13 +133,19 @@ static __inline int logical_smp_processor_id(void) /* we don't want to mark this access volatile - bad code generation */ return GET_APIC_LOGICAL_ID(*(unsigned long *)(APIC_BASE+APIC_LDR)); } -#endif #ifdef CONFIG_SMP #define cpu_physical_id(cpu) x86_cpu_to_apicid[cpu] #else #define cpu_physical_id(cpu) boot_cpu_id -#endif - +static inline int smp_call_function_single(int cpuid, void (*func) (void *info), + void *info, int retry, int wait) +{ + /* Disable interrupts here? */ + func(info); + return 0; +} +#endif /* !CONFIG_SMP */ +#endif /* !__ASSEMBLY */ #endif diff --git a/include/asm-x86_64/vsyscall.h b/include/asm-x86_64/vsyscall.h index 146b24402a5..2281e9399b9 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 v1.2.3-70-g09d2