guest_enter() doesn't call context_tracking_enabled() before calling
context_tracking_enabled_this_cpu(). Therefore the guest code doesn't
benefit from the static key on the fast path.
Just make sure that context_tracking_enabled_*cpu() functions check
the static key by themselves to propagate the optimization.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-11-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
static inline bool context_tracking_enabled_cpu(int cpu)
{
- return per_cpu(context_tracking.active, cpu);
+ return context_tracking_enabled() && per_cpu(context_tracking.active, cpu);
}
static inline bool context_tracking_enabled_this_cpu(void)
{
- return __this_cpu_read(context_tracking.active);
+ return context_tracking_enabled() && __this_cpu_read(context_tracking.active);
}
static inline bool context_tracking_in_user(void)
static inline bool vtime_accounting_enabled_cpu(int cpu)
{
- return (vtime_accounting_enabled() && context_tracking_enabled_cpu(cpu));
+ return context_tracking_enabled_cpu(cpu);
}
static inline bool vtime_accounting_enabled_this_cpu(void)
{
- return (vtime_accounting_enabled() && context_tracking_enabled_this_cpu());
+ return context_tracking_enabled_this_cpu();
}
extern void vtime_task_switch_generic(struct task_struct *prev);