diff options
Diffstat (limited to 'include/linux/tracepoint.h')
| -rw-r--r-- | include/linux/tracepoint.h | 167 |
1 files changed, 94 insertions, 73 deletions
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 1fb11daa5c53..4b33b95eb8be 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -19,6 +19,7 @@ #include <linux/cpumask.h> #include <linux/rcupdate.h> #include <linux/tracepoint-defs.h> +#include <linux/static_call.h> struct module; struct tracepoint; @@ -40,7 +41,17 @@ extern int tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, void *data, int prio); extern int +tracepoint_probe_register_prio_may_exist(struct tracepoint *tp, void *probe, void *data, + int prio); +extern int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data); +static inline int +tracepoint_probe_register_may_exist(struct tracepoint *tp, void *probe, + void *data) +{ + return tracepoint_probe_register_prio_may_exist(tp, probe, data, + TRACEPOINT_DEFAULT_PRIO); +} extern void for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv), void *priv); @@ -92,7 +103,9 @@ extern int syscall_regfunc(void); extern void syscall_unregfunc(void); #endif /* CONFIG_HAVE_SYSCALL_TRACEPOINTS */ +#ifndef PARAMS #define PARAMS(args...) args +#endif #define TRACE_DEFINE_ENUM(x) #define TRACE_DEFINE_SIZEOF(x) @@ -116,8 +129,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) #define __TRACEPOINT_ENTRY(name) \ static tracepoint_ptr_t __tracepoint_ptr_##name __used \ - __attribute__((section("__tracepoints_ptrs"))) = \ - &__tracepoint_##name + __section("__tracepoints_ptrs") = &__tracepoint_##name #endif #endif /* _LINUX_TRACEPOINT_H */ @@ -139,7 +151,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) /* * Individual subsystem my have a separate configuration to * enable their tracepoints. By default, this file will create - * the tracepoints if CONFIG_TRACEPOINT is defined. If a subsystem + * the tracepoints if CONFIG_TRACEPOINTS is defined. If a subsystem * wants to be able to disable its tracepoints from being created * it can define NOTRACE before including the tracepoint headers. */ @@ -149,21 +161,28 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) #ifdef TRACEPOINTS_ENABLED +#ifdef CONFIG_HAVE_STATIC_CALL +#define __DO_TRACE_CALL(name, args) \ + do { \ + struct tracepoint_func *it_func_ptr; \ + void *__data; \ + it_func_ptr = \ + rcu_dereference_raw((&__tracepoint_##name)->funcs); \ + if (it_func_ptr) { \ + __data = (it_func_ptr)->data; \ + static_call(tp_func_##name)(__data, args); \ + } \ + } while (0) +#else +#define __DO_TRACE_CALL(name, args) __traceiter_##name(NULL, args) +#endif /* CONFIG_HAVE_STATIC_CALL */ + /* * it_func[0] is never NULL because there is at least one element in the array * when the array itself is non NULL. - * - * Note, the proto and args passed in includes "__data" as the first parameter. - * The reason for this is to handle the "void" prototype. If a tracepoint - * has a "void" prototype, then it is invalid to declare a function - * as "(void *, void)". The DECLARE_TRACE_NOARGS() will pass in just - * "void *data", where as the DECLARE_TRACE() will pass in "void *data, proto". */ -#define __DO_TRACE(tp, proto, args, cond, rcuidle) \ +#define __DO_TRACE(name, args, cond, rcuidle) \ do { \ - struct tracepoint_func *it_func_ptr; \ - void *it_func; \ - void *__data; \ int __maybe_unused __idx = 0; \ \ if (!(cond)) \ @@ -181,21 +200,13 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) */ \ if (rcuidle) { \ __idx = srcu_read_lock_notrace(&tracepoint_srcu);\ - rcu_irq_enter_irqson(); \ + ct_irq_enter_irqson(); \ } \ \ - it_func_ptr = rcu_dereference_raw((tp)->funcs); \ - \ - if (it_func_ptr) { \ - do { \ - it_func = (it_func_ptr)->func; \ - __data = (it_func_ptr)->data; \ - ((void(*)(proto))(it_func))(args); \ - } while ((++it_func_ptr)->func); \ - } \ + __DO_TRACE_CALL(name, TP_ARGS(args)); \ \ if (rcuidle) { \ - rcu_irq_exit_irqson(); \ + ct_irq_exit_irqson(); \ srcu_read_unlock_notrace(&tracepoint_srcu, __idx);\ } \ \ @@ -203,17 +214,16 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) } while (0) #ifndef MODULE -#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) \ +#define __DECLARE_TRACE_RCU(name, proto, args, cond) \ static inline void trace_##name##_rcuidle(proto) \ { \ if (static_key_false(&__tracepoint_##name.key)) \ - __DO_TRACE(&__tracepoint_##name, \ - TP_PROTO(data_proto), \ - TP_ARGS(data_args), \ + __DO_TRACE(name, \ + TP_ARGS(args), \ TP_CONDITION(cond), 1); \ } #else -#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) +#define __DECLARE_TRACE_RCU(name, proto, args, cond) #endif /* @@ -228,14 +238,15 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) * even when this tracepoint is off. This code has no purpose other than * poking RCU a bit. */ -#define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \ +#define __DECLARE_TRACE(name, proto, args, cond, data_proto) \ + extern int __traceiter_##name(data_proto); \ + DECLARE_STATIC_CALL(tp_func_##name, __traceiter_##name); \ extern struct tracepoint __tracepoint_##name; \ static inline void trace_##name(proto) \ { \ if (static_key_false(&__tracepoint_##name.key)) \ - __DO_TRACE(&__tracepoint_##name, \ - TP_PROTO(data_proto), \ - TP_ARGS(data_args), \ + __DO_TRACE(name, \ + TP_ARGS(args), \ TP_CONDITION(cond), 0); \ if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) { \ rcu_read_lock_sched_notrace(); \ @@ -244,7 +255,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) } \ } \ __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args), \ - PARAMS(cond), PARAMS(data_proto), PARAMS(data_args)) \ + PARAMS(cond)) \ static inline int \ register_trace_##name(void (*probe)(data_proto), void *data) \ { \ @@ -279,24 +290,55 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) * structures, so we create an array of pointers that will be used for iteration * on the tracepoints. */ -#define DEFINE_TRACE_FN(name, reg, unreg) \ - static const char __tpstrtab_##name[] \ - __attribute__((section("__tracepoints_strings"))) = #name; \ - struct tracepoint __tracepoint_##name \ - __attribute__((section("__tracepoints"), used)) = \ - { __tpstrtab_##name, STATIC_KEY_INIT_FALSE, reg, unreg, NULL };\ - __TRACEPOINT_ENTRY(name); +#define DEFINE_TRACE_FN(_name, _reg, _unreg, proto, args) \ + static const char __tpstrtab_##_name[] \ + __section("__tracepoints_strings") = #_name; \ + extern struct static_call_key STATIC_CALL_KEY(tp_func_##_name); \ + int __traceiter_##_name(void *__data, proto); \ + struct tracepoint __tracepoint_##_name __used \ + __section("__tracepoints") = { \ + .name = __tpstrtab_##_name, \ + .key = STATIC_KEY_INIT_FALSE, \ + .static_call_key = &STATIC_CALL_KEY(tp_func_##_name), \ + .static_call_tramp = STATIC_CALL_TRAMP_ADDR(tp_func_##_name), \ + .iterator = &__traceiter_##_name, \ + .regfunc = _reg, \ + .unregfunc = _unreg, \ + .funcs = NULL }; \ + __TRACEPOINT_ENTRY(_name); \ + int __traceiter_##_name(void *__data, proto) \ + { \ + struct tracepoint_func *it_func_ptr; \ + void *it_func; \ + \ + it_func_ptr = \ + rcu_dereference_raw((&__tracepoint_##_name)->funcs); \ + if (it_func_ptr) { \ + do { \ + it_func = READ_ONCE((it_func_ptr)->func); \ + __data = (it_func_ptr)->data; \ + ((void(*)(void *, proto))(it_func))(__data, args); \ + } while ((++it_func_ptr)->func); \ + } \ + return 0; \ + } \ + DEFINE_STATIC_CALL(tp_func_##_name, __traceiter_##_name); -#define DEFINE_TRACE(name) \ - DEFINE_TRACE_FN(name, NULL, NULL); +#define DEFINE_TRACE(name, proto, args) \ + DEFINE_TRACE_FN(name, NULL, NULL, PARAMS(proto), PARAMS(args)); #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \ - EXPORT_SYMBOL_GPL(__tracepoint_##name) + EXPORT_SYMBOL_GPL(__tracepoint_##name); \ + EXPORT_SYMBOL_GPL(__traceiter_##name); \ + EXPORT_STATIC_CALL_GPL(tp_func_##name) #define EXPORT_TRACEPOINT_SYMBOL(name) \ - EXPORT_SYMBOL(__tracepoint_##name) + EXPORT_SYMBOL(__tracepoint_##name); \ + EXPORT_SYMBOL(__traceiter_##name); \ + EXPORT_STATIC_CALL(tp_func_##name) + #else /* !TRACEPOINTS_ENABLED */ -#define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \ +#define __DECLARE_TRACE(name, proto, args, cond, data_proto) \ static inline void trace_##name(proto) \ { } \ static inline void trace_##name##_rcuidle(proto) \ @@ -322,8 +364,8 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) return false; \ } -#define DEFINE_TRACE_FN(name, reg, unreg) -#define DEFINE_TRACE(name) +#define DEFINE_TRACE_FN(name, reg, unreg, proto, args) +#define DEFINE_TRACE(name, proto, args) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) @@ -362,7 +404,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) static const char *___tp_str __tracepoint_string = str; \ ___tp_str; \ }) -#define __tracepoint_string __attribute__((section("__tracepoint_str"))) +#define __tracepoint_string __used __section("__tracepoint_str") #else /* * tracepoint_string() is used to save the string address for userspace @@ -373,36 +415,15 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) # define __tracepoint_string #endif -/* - * The need for the DECLARE_TRACE_NOARGS() is to handle the prototype - * (void). "void" is a special value in a function prototype and can - * not be combined with other arguments. Since the DECLARE_TRACE() - * macro adds a data element at the beginning of the prototype, - * we need a way to differentiate "(void *data, proto)" from - * "(void *data, void)". The second prototype is invalid. - * - * DECLARE_TRACE_NOARGS() passes "void" as the tracepoint prototype - * and "void *__data" as the callback prototype. - * - * DECLARE_TRACE() passes "proto" as the tracepoint protoype and - * "void *__data, proto" as the callback prototype. - */ -#define DECLARE_TRACE_NOARGS(name) \ - __DECLARE_TRACE(name, void, , \ - cpu_online(raw_smp_processor_id()), \ - void *__data, __data) - #define DECLARE_TRACE(name, proto, args) \ __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \ cpu_online(raw_smp_processor_id()), \ - PARAMS(void *__data, proto), \ - PARAMS(__data, args)) + PARAMS(void *__data, proto)) #define DECLARE_TRACE_CONDITION(name, proto, args, cond) \ __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \ cpu_online(raw_smp_processor_id()) && (PARAMS(cond)), \ - PARAMS(void *__data, proto), \ - PARAMS(__data, args)) + PARAMS(void *__data, proto)) #define TRACE_EVENT_FLAGS(event, flag) @@ -454,7 +475,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) * * * * The declared 'local variable' is called '__entry' * * - * * __field(pid_t, prev_prid) is equivalent to a standard declariton: + * * __field(pid_t, prev_pid) is equivalent to a standard declaration: * * * * pid_t prev_pid; * * |