On Tue, 05 May 2020 15:16:35 +0200 Thomas Gleixner <[email protected]> wrote:
> From: Peter Zijlstra <[email protected]> > > ftrace_nmi_enter() > trace_hwlat_callback() > trace_clock_local() > sched_clock() > paravirt_sched_clock() > native_sched_clock() > > All must not be traced or kprobed, it will be called from do_debug() > before the kprobe handler. > Looks good to me. Reviewed-by: Masami Hiramatsu <[email protected]> Thank you, > Signed-off-by: Peter Zijlstra (Intel) <[email protected]> > Signed-off-by: Thomas Gleixner <[email protected]> > Acked-by: Steven Rostedt (VMware) <[email protected]> > --- > arch/x86/include/asm/paravirt.h | 2 +- > arch/x86/kernel/tsc.c | 4 ++-- > include/linux/ftrace_irq.h | 4 ++-- > kernel/trace/trace_clock.c | 3 ++- > kernel/trace/trace_hwlat.c | 2 +- > 5 files changed, 8 insertions(+), 7 deletions(-) > > --- a/arch/x86/include/asm/paravirt.h > +++ b/arch/x86/include/asm/paravirt.h > @@ -17,7 +17,7 @@ > #include <linux/cpumask.h> > #include <asm/frame.h> > > -static inline unsigned long long paravirt_sched_clock(void) > +static __always_inline unsigned long long paravirt_sched_clock(void) > { > return PVOP_CALL0(unsigned long long, time.sched_clock); > } > --- a/arch/x86/kernel/tsc.c > +++ b/arch/x86/kernel/tsc.c > @@ -207,7 +207,7 @@ static void __init cyc2ns_init_secondary > /* > * Scheduler clock - returns current time in nanosec units. > */ > -u64 native_sched_clock(void) > +noinstr u64 native_sched_clock(void) > { > if (static_branch_likely(&__use_tsc)) { > u64 tsc_now = rdtsc(); > @@ -240,7 +240,7 @@ u64 native_sched_clock_from_tsc(u64 tsc) > /* We need to define a real function for sched_clock, to override the > weak default version */ > #ifdef CONFIG_PARAVIRT > -unsigned long long sched_clock(void) > +noinstr unsigned long long sched_clock(void) > { > return paravirt_sched_clock(); > } > --- a/include/linux/ftrace_irq.h > +++ b/include/linux/ftrace_irq.h > @@ -7,7 +7,7 @@ extern bool trace_hwlat_callback_enabled > extern void trace_hwlat_callback(bool enter); > #endif > > -static inline void ftrace_nmi_enter(void) > +static __always_inline void ftrace_nmi_enter(void) > { > #ifdef CONFIG_HWLAT_TRACER > if (trace_hwlat_callback_enabled) > @@ -15,7 +15,7 @@ static inline void ftrace_nmi_enter(void > #endif > } > > -static inline void ftrace_nmi_exit(void) > +static __always_inline void ftrace_nmi_exit(void) > { > #ifdef CONFIG_HWLAT_TRACER > if (trace_hwlat_callback_enabled) > --- a/kernel/trace/trace_clock.c > +++ b/kernel/trace/trace_clock.c > @@ -22,6 +22,7 @@ > #include <linux/sched/clock.h> > #include <linux/ktime.h> > #include <linux/trace_clock.h> > +#include <linux/kprobes.h> > > /* > * trace_clock_local(): the simplest and least coherent tracing clock. > @@ -29,7 +30,7 @@ > * Useful for tracing that does not cross to other CPUs nor > * does it go through idle events. > */ > -u64 notrace trace_clock_local(void) > +u64 noinstr trace_clock_local(void) > { > u64 clock; > > --- a/kernel/trace/trace_hwlat.c > +++ b/kernel/trace/trace_hwlat.c > @@ -139,7 +139,7 @@ static void trace_hwlat_sample(struct hw > #define init_time(a, b) (a = b) > #define time_u64(a) a > > -void trace_hwlat_callback(bool enter) > +noinstr void trace_hwlat_callback(bool enter) > { > if (smp_processor_id() != nmi_cpu) > return; > -- Masami Hiramatsu <[email protected]>
