context_tracking: Optimize guest APIs off case with static key
Optimize guest entry/exit APIs with static keys. This minimize the overhead for those who enable CONFIG_NO_HZ_FULL without always using it. Having no range passed to nohz_full= should result in the probes overhead to be minimized. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
This commit is contained in:
parent
ad65782fba
commit
48d6a816a8
3 changed files with 21 additions and 23 deletions
|
@ -95,8 +95,23 @@ static inline void context_tracking_init(void) { }
|
||||||
|
|
||||||
|
|
||||||
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
|
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
|
||||||
extern void guest_enter(void);
|
static inline void guest_enter(void)
|
||||||
extern void guest_exit(void);
|
{
|
||||||
|
if (static_key_false(&context_tracking_enabled) &&
|
||||||
|
vtime_accounting_enabled())
|
||||||
|
vtime_guest_enter(current);
|
||||||
|
else
|
||||||
|
current->flags |= PF_VCPU;
|
||||||
|
}
|
||||||
|
|
||||||
|
static inline void guest_exit(void)
|
||||||
|
{
|
||||||
|
if (static_key_false(&context_tracking_enabled) &&
|
||||||
|
vtime_accounting_enabled())
|
||||||
|
vtime_guest_exit(current);
|
||||||
|
else
|
||||||
|
current->flags &= ~PF_VCPU;
|
||||||
|
}
|
||||||
#else
|
#else
|
||||||
static inline void guest_enter(void)
|
static inline void guest_enter(void)
|
||||||
{
|
{
|
||||||
|
|
|
@ -21,8 +21,10 @@
|
||||||
#include <linux/export.h>
|
#include <linux/export.h>
|
||||||
|
|
||||||
struct static_key context_tracking_enabled = STATIC_KEY_INIT_FALSE;
|
struct static_key context_tracking_enabled = STATIC_KEY_INIT_FALSE;
|
||||||
|
EXPORT_SYMBOL_GPL(context_tracking_enabled);
|
||||||
|
|
||||||
DEFINE_PER_CPU(struct context_tracking, context_tracking);
|
DEFINE_PER_CPU(struct context_tracking, context_tracking);
|
||||||
|
EXPORT_SYMBOL_GPL(context_tracking);
|
||||||
|
|
||||||
void context_tracking_cpu_set(int cpu)
|
void context_tracking_cpu_set(int cpu)
|
||||||
{
|
{
|
||||||
|
@ -163,27 +165,6 @@ void context_tracking_user_exit(void)
|
||||||
local_irq_restore(flags);
|
local_irq_restore(flags);
|
||||||
}
|
}
|
||||||
|
|
||||||
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
|
|
||||||
void guest_enter(void)
|
|
||||||
{
|
|
||||||
if (vtime_accounting_enabled())
|
|
||||||
vtime_guest_enter(current);
|
|
||||||
else
|
|
||||||
current->flags |= PF_VCPU;
|
|
||||||
}
|
|
||||||
EXPORT_SYMBOL_GPL(guest_enter);
|
|
||||||
|
|
||||||
void guest_exit(void)
|
|
||||||
{
|
|
||||||
if (vtime_accounting_enabled())
|
|
||||||
vtime_guest_exit(current);
|
|
||||||
else
|
|
||||||
current->flags &= ~PF_VCPU;
|
|
||||||
}
|
|
||||||
EXPORT_SYMBOL_GPL(guest_exit);
|
|
||||||
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
|
|
||||||
|
|
||||||
|
|
||||||
/**
|
/**
|
||||||
* context_tracking_task_switch - context switch the syscall callbacks
|
* context_tracking_task_switch - context switch the syscall callbacks
|
||||||
* @prev: the task that is being switched out
|
* @prev: the task that is being switched out
|
||||||
|
|
|
@ -724,6 +724,7 @@ void vtime_guest_enter(struct task_struct *tsk)
|
||||||
current->flags |= PF_VCPU;
|
current->flags |= PF_VCPU;
|
||||||
write_sequnlock(&tsk->vtime_seqlock);
|
write_sequnlock(&tsk->vtime_seqlock);
|
||||||
}
|
}
|
||||||
|
EXPORT_SYMBOL_GPL(vtime_guest_enter);
|
||||||
|
|
||||||
void vtime_guest_exit(struct task_struct *tsk)
|
void vtime_guest_exit(struct task_struct *tsk)
|
||||||
{
|
{
|
||||||
|
@ -732,6 +733,7 @@ void vtime_guest_exit(struct task_struct *tsk)
|
||||||
current->flags &= ~PF_VCPU;
|
current->flags &= ~PF_VCPU;
|
||||||
write_sequnlock(&tsk->vtime_seqlock);
|
write_sequnlock(&tsk->vtime_seqlock);
|
||||||
}
|
}
|
||||||
|
EXPORT_SYMBOL_GPL(vtime_guest_exit);
|
||||||
|
|
||||||
void vtime_account_idle(struct task_struct *tsk)
|
void vtime_account_idle(struct task_struct *tsk)
|
||||||
{
|
{
|
||||||
|
|
Loading…
Reference in a new issue