Steven Rostedt
2007-Apr-18 13:02 UTC
[RFC/PATCH PV_OPS X86_64 14/17] paravirt_ops - vsyscall
plain text document attachment (xx-paravirt-vsyscall.patch) vsyscall interface updates for paravirt ops. Signed-off-by: Steven Rostedt srostedt@redhat.com Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Index: clean-start/arch/x86_64/kernel/vsyscall.c ==================================================================--- clean-start.orig/arch/x86_64/kernel/vsyscall.c +++ clean-start/arch/x86_64/kernel/vsyscall.c @@ -73,7 +73,7 @@ static __always_inline void do_vgettimeo usec = __xtime.tv_nsec / 1000; if (__vxtime.mode != VXTIME_HPET) { - t = get_cycles_sync(); + t = vget_cycles_sync(); if (t < __vxtime.last_tsc) t = __vxtime.last_tsc; usec += ((t - __vxtime.last_tsc) * @@ -147,8 +147,8 @@ time_t __vsyscall(1) vtime(time_t *t) long __vsyscall(2) vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache) { - unsigned int dummy, p; - unsigned long j = 0; + unsigned int p; + unsigned long dummy, j = 0; /* Fast cache - only recompute value once per jiffies and avoid relatively costly rdtscp/cpuid otherwise. @@ -162,7 +162,8 @@ vgetcpu(unsigned *cpu, unsigned *node, s p = tcache->blob[1]; } else if (__vgetcpu_mode == VGETCPU_RDTSCP) { /* Load per CPU data from RDTSCP */ - rdtscp(dummy, dummy, p); + /* rdtscp() cannot be called due to the paravirt indirection */ + asm("rdtscp" : "=A" (dummy), "=c" (p)); } else { /* Load per CPU data from GDT */ asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG)); @@ -256,7 +257,11 @@ static void __cpuinit vsyscall_set_cpu(i node = cpu_to_node[cpu]; #endif if (cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP)) - write_rdtscp_aux((node << 12) | cpu); + /* This is write_rdtscp_aux. It cannot be called directly + * due to the paravirt indirection */ + asm("wrmsr" : /* no output */ + : "d"(0), + "a" ((node << 12) | cpu), "c" (0xc0000103)); /* Store cpu number in limit so that it can be loaded quickly in user space in vgetcpu. @@ -285,8 +290,12 @@ cpu_vsyscall_notifier(struct notifier_bl static void __init map_vsyscall(void) { +#ifndef CONFIG_PARAVIRT extern char __vsyscall_0; unsigned long physaddr_page0 = __pa_symbol(&__vsyscall_0); +#else + unsigned long physaddr_page0 = __pa_symbol(paravirt_ops.vsyscall_page); +#endif /* Note that VSYSCALL_MAPPED_PAGES must agree with the code below. */ __set_fixmap(VSYSCALL_FIRST_PAGE, physaddr_page0, PAGE_KERNEL_VSYSCALL); @@ -299,7 +308,14 @@ static int __init vsyscall_init(void) BUG_ON((unsigned long) &vtime != VSYSCALL_ADDR(__NR_vtime)); BUG_ON((VSYSCALL_ADDR(0) != __fix_to_virt(VSYSCALL_FIRST_PAGE))); BUG_ON((unsigned long) &vgetcpu != VSYSCALL_ADDR(__NR_vgetcpu)); - map_vsyscall(); +#ifdef CONFIG_PARAVIRT + if (paravirt_ops.vsyscall_page) +#endif + map_vsyscall(); +#ifdef CONFIG_PARAVIRT + else + __sysctl_vsyscall = 0; +#endif #ifdef CONFIG_SYSCTL register_sysctl_table(kernel_root_table2, 0); #endif --