diff options
| author | Frederic Weisbecker <fweisbec@gmail.com> | 2013-07-10 02:44:35 +0200 |
|---|---|---|
| committer | Frederic Weisbecker <fweisbec@gmail.com> | 2013-08-14 17:14:46 +0200 |
| commit | 48d6a816a8bf36e2a197c322697323003bdc1cfe (patch) | |
| tree | 6a51b602ec4451b8443b2b58337e9a55c84ceb48 /include/linux/context_tracking.h | |
| parent | ad65782fba507d91a0a98f519b59e79cac1b474c (diff) | |
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>
Diffstat (limited to 'include/linux/context_tracking.h')
| -rw-r--r-- | include/linux/context_tracking.h | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index 38ab60b3f3a6..8854eadb2142 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -95,8 +95,23 @@ static inline void context_tracking_init(void) { } #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN -extern void guest_enter(void); -extern void guest_exit(void); +static inline void guest_enter(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 static inline void guest_enter(void) { |