From f927da178671a824cf6c530f0623544206387e57 Mon Sep 17 00:00:00 2001 From: Isaku Yamahata Date: Wed, 4 Mar 2009 21:05:40 +0900 Subject: ia64/pv_ops/pv_time_ops: add sched_clock hook. add sched_clock() hook to paravirtualize sched_clock(). ia64 sched_clock() is based on ar.itc which isn't stable on virtualized environment because vcpu may move around on pcpus. So it needs paravirtualization. Signed-off-by: Isaku Yamahata Signed-off-by: Tony Luck --- arch/ia64/kernel/head.S | 10 ++++++++-- arch/ia64/kernel/paravirt.c | 1 + arch/ia64/kernel/time.c | 9 +++++++++ 3 files changed, 18 insertions(+), 2 deletions(-) (limited to 'arch/ia64/kernel') diff --git a/arch/ia64/kernel/head.S b/arch/ia64/kernel/head.S index 59301c47280..23f846de62d 100644 --- a/arch/ia64/kernel/head.S +++ b/arch/ia64/kernel/head.S @@ -1050,7 +1050,7 @@ END(ia64_delay_loop) * except that the multiplication and the shift are done with 128-bit * intermediate precision so that we can produce a full 64-bit result. */ -GLOBAL_ENTRY(sched_clock) +GLOBAL_ENTRY(ia64_native_sched_clock) addl r8=THIS_CPU(cpu_info) + IA64_CPUINFO_NSEC_PER_CYC_OFFSET,r0 mov.m r9=ar.itc // fetch cycle-counter (35 cyc) ;; @@ -1066,7 +1066,13 @@ GLOBAL_ENTRY(sched_clock) ;; shrp r8=r9,r8,IA64_NSEC_PER_CYC_SHIFT br.ret.sptk.many rp -END(sched_clock) +END(ia64_native_sched_clock) +#ifndef CONFIG_PARAVIRT + //unsigned long long + //sched_clock(void) __attribute__((alias("ia64_native_sched_clock"))); + .global sched_clock +sched_clock = ia64_native_sched_clock +#endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING GLOBAL_ENTRY(cycle_to_cputime) diff --git a/arch/ia64/kernel/paravirt.c b/arch/ia64/kernel/paravirt.c index 9f14c16f636..6bc33a6db75 100644 --- a/arch/ia64/kernel/paravirt.c +++ b/arch/ia64/kernel/paravirt.c @@ -366,4 +366,5 @@ ia64_native_do_steal_accounting(unsigned long *new_itm) struct pv_time_ops pv_time_ops = { .do_steal_accounting = ia64_native_do_steal_accounting, + .sched_clock = ia64_native_sched_clock, }; diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c index f0ebb342409..c323c7b9c77 100644 --- a/arch/ia64/kernel/time.c +++ b/arch/ia64/kernel/time.c @@ -49,6 +49,15 @@ EXPORT_SYMBOL(last_cli_ip); #endif +#ifdef CONFIG_PARAVIRT +/* We need to define a real function for sched_clock, to override the + weak default version */ +unsigned long long sched_clock(void) +{ + return paravirt_sched_clock(); +} +#endif + #ifdef CONFIG_PARAVIRT static void paravirt_clocksource_resume(void) -- cgit v1.2.3