From 2d854e5738cded368a0759f85b1197f5c044513d Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 12 Jul 2013 19:02:30 +0200 Subject: context_tracing: Fix guest accounting with native vtime 1) If context tracking is enabled with native vtime accounting (which combo is useless except for dev testing), we call vtime_guest_enter() and vtime_guest_exit() on host <-> guest switches. But those are stubs in this configurations. As a result, cputime is not correctly flushed on kvm context switches. 2) If context tracking runs but is disabled on some CPUs, those CPUs end up calling __guest_enter/__guest_exit which in turn call vtime_account_system(). We don't want to call this because we run in tick based accounting for these CPUs. Refactor the guest_enter/guest_exit code such that all combinations finally work. Signed-off-by: Frederic Weisbecker Cc: Steven Rostedt Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Li Zhong Cc: Mike Galbraith Cc: Kevin Hilman --- kernel/context_tracking.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'kernel/context_tracking.c') diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c index 942835c12ae5..1f47119c5b09 100644 --- a/kernel/context_tracking.c +++ b/kernel/context_tracking.c @@ -141,12 +141,13 @@ void user_exit(void) local_irq_restore(flags); } +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN void guest_enter(void) { if (vtime_accounting_enabled()) vtime_guest_enter(current); else - __guest_enter(); + current->flags |= PF_VCPU; } EXPORT_SYMBOL_GPL(guest_enter); @@ -155,9 +156,10 @@ void guest_exit(void) if (vtime_accounting_enabled()) vtime_guest_exit(current); else - __guest_exit(); + current->flags &= ~PF_VCPU; } EXPORT_SYMBOL_GPL(guest_exit); +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */ /** -- cgit