From: Mathieu Desnoyers <[email protected]> Introduce a "faultable" flag within the extended structure to know whether a tracepoint needs rcu tasks trace grace period before reclaim. This can be queried using tracepoint_is_faultable().
Acked-by: Andrii Nakryiko <[email protected]> Tested-by: Jordan Rife <[email protected]> Cc: Michael Jeanson <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Yonghong Song <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Andrii Nakryiko <[email protected]> Cc: [email protected] Cc: Joel Fernandes <[email protected]> Cc: Jordan Rife <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/[email protected] Signed-off-by: Mathieu Desnoyers <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]> --- include/linux/tracepoint-defs.h | 2 ++ include/linux/tracepoint.h | 24 ++++++++++++++++++++++++ include/trace/define_trace.h | 2 +- 3 files changed, 27 insertions(+), 1 deletion(-) diff --git a/include/linux/tracepoint-defs.h b/include/linux/tracepoint-defs.h index 967c08d9da84..aebf0571c736 100644 --- a/include/linux/tracepoint-defs.h +++ b/include/linux/tracepoint-defs.h @@ -32,6 +32,8 @@ struct tracepoint_func { struct tracepoint_ext { int (*regfunc)(void); void (*unregfunc)(void); + /* Flags. */ + unsigned int faultable:1; }; struct tracepoint { diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 862ab49177a4..906f3091d23d 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -104,6 +104,12 @@ void for_each_tracepoint_in_module(struct module *mod, * tracepoint_synchronize_unregister must be called between the last tracepoint * probe unregistration and the end of module exit to make sure there is no * caller executing a probe when it is freed. + * + * An alternative is to use the following for batch reclaim associated + * with a given tracepoint: + * + * - tracepoint_is_faultable() == false: call_rcu() + * - tracepoint_is_faultable() == true: call_rcu_tasks_trace() */ #ifdef CONFIG_TRACEPOINTS static inline void tracepoint_synchronize_unregister(void) @@ -111,9 +117,17 @@ static inline void tracepoint_synchronize_unregister(void) synchronize_rcu_tasks_trace(); synchronize_rcu(); } +static inline bool tracepoint_is_faultable(struct tracepoint *tp) +{ + return tp->ext && tp->ext->faultable; +} #else static inline void tracepoint_synchronize_unregister(void) { } +static inline bool tracepoint_is_faultable(struct tracepoint *tp) +{ + return false; +} #endif #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS @@ -345,6 +359,15 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) static struct tracepoint_ext __tracepoint_ext_##_name = { \ .regfunc = _reg, \ .unregfunc = _unreg, \ + .faultable = false, \ + }; \ + __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARAMS(_args)); + +#define DEFINE_TRACE_SYSCALL(_name, _reg, _unreg, _proto, _args) \ + static struct tracepoint_ext __tracepoint_ext_##_name = { \ + .regfunc = _reg, \ + .unregfunc = _unreg, \ + .faultable = true, \ }; \ __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARAMS(_args)); @@ -389,6 +412,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) #define __DECLARE_TRACE_SYSCALL __DECLARE_TRACE #define DEFINE_TRACE_FN(name, reg, unreg, proto, args) +#define DEFINE_TRACE_SYSCALL(name, reg, unreg, proto, args) #define DEFINE_TRACE(name, proto, args) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) diff --git a/include/trace/define_trace.h b/include/trace/define_trace.h index ff5fa17a6259..63fea2218afa 100644 --- a/include/trace/define_trace.h +++ b/include/trace/define_trace.h @@ -48,7 +48,7 @@ #undef TRACE_EVENT_SYSCALL #define TRACE_EVENT_SYSCALL(name, proto, args, struct, assign, print, reg, unreg) \ - DEFINE_TRACE_FN(name, reg, unreg, PARAMS(proto), PARAMS(args)) + DEFINE_TRACE_SYSCALL(name, reg, unreg, PARAMS(proto), PARAMS(args)) #undef TRACE_EVENT_NOP #define TRACE_EVENT_NOP(name, proto, args, struct, assign, print) -- 2.45.2
