1 files changed, 56 insertions, 29 deletions

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 103d1b61aacb..d530a4460a0b 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -17,6 +17,7 @@
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/rcupdate.h>
+#include <linux/jump_label.h>
 
 struct module;
 struct tracepoint;
@@ -28,16 +29,11 @@ struct tracepoint_func {
 
 struct tracepoint {
         const char *name;               /* Tracepoint name */
-        int state;                      /* State. */
+        struct jump_label_key key;
         void (*regfunc)(void);
         void (*unregfunc)(void);
-        struct tracepoint_func *funcs;
-} __attribute__((aligned(32)));         /*
-                                         * Aligned on 32 bytes because it is
-                                         * globally visible and gcc happily
-                                         * align these on the structure size.
-                                         * Keep in sync with vmlinux.lds.h.
-                                         */
+        struct tracepoint_func __rcu *funcs;
+};
 
 /*
  * Connect a probe to a tracepoint.
@@ -60,15 +56,15 @@ extern void tracepoint_probe_update_all(void);
 
 struct tracepoint_iter {
         struct module *module;
-        struct tracepoint *tracepoint;
+        struct tracepoint * const *tracepoint;
 };
 
 extern void tracepoint_iter_start(struct tracepoint_iter *iter);
 extern void tracepoint_iter_next(struct tracepoint_iter *iter);
 extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
 extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
-extern int tracepoint_get_iter_range(struct tracepoint **tracepoint,
-        struct tracepoint *begin, struct tracepoint *end);
+extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
+        struct tracepoint * const *begin, struct tracepoint * const *end);
 
 /*
  * tracepoint_synchronize_unregister must be called between the last tracepoint
@@ -83,11 +79,13 @@ static inline void tracepoint_synchronize_unregister(void)
 #define PARAMS(args...) args
 
 #ifdef CONFIG_TRACEPOINTS
-extern void tracepoint_update_probe_range(struct tracepoint *begin,
-        struct tracepoint *end);
+extern
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+        struct tracepoint * const *end);
 #else
-static inline void tracepoint_update_probe_range(struct tracepoint *begin,
-        struct tracepoint *end)
+static inline
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+        struct tracepoint * const *end)
 { }
 #endif /* CONFIG_TRACEPOINTS */
 
@@ -105,6 +103,7 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
 
 #define TP_PROTO(args...)       args
 #define TP_ARGS(args...)        args
+#define TP_CONDITION(args...)   args
 
 #ifdef CONFIG_TRACEPOINTS
 
@@ -118,12 +117,14 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
  * 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)                                     \
+#define __DO_TRACE(tp, proto, args, cond)                               \
         do {                                                            \
                 struct tracepoint_func *it_func_ptr;                    \
                 void *it_func;                                          \
                 void *__data;                                           \
                                                                         \
+                if (!(cond))                                            \
+                        return;                                         \
                 rcu_read_lock_sched_notrace();                          \
                 it_func_ptr = rcu_dereference_sched((tp)->funcs);       \
                 if (it_func_ptr) {                                      \
@@ -141,14 +142,15 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
  * not add unwanted padding between the beginning of the section and the
  * structure. Force alignment to the same alignment as the section start.
  */
-#define __DECLARE_TRACE(name, proto, args, data_proto, data_args)       \
+#define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \
         extern struct tracepoint __tracepoint_##name;                   \
         static inline void trace_##name(proto)                          \
         {                                                               \
-                if (unlikely(__tracepoint_##name.state))                \
+                if (static_branch(&__tracepoint_##name.key))            \
                         __DO_TRACE(&__tracepoint_##name,                \
                                 TP_PROTO(data_proto),                   \
-                                TP_ARGS(data_args));                    \
+                                TP_ARGS(data_args),                     \
+                                TP_CONDITION(cond));                    \
         }                                                               \
         static inline int                                               \
         register_trace_##name(void (*probe)(data_proto), void *data)    \
@@ -167,12 +169,20 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
         {                                                               \
         }
 
-#define DEFINE_TRACE_FN(name, reg, unreg)                               \
-        static const char __tpstrtab_##name[]                           \
-        __attribute__((section("__tracepoints_strings"))) = #name;      \
-        struct tracepoint __tracepoint_##name                           \
-        __attribute__((section("__tracepoints"), aligned(32))) =        \
-                { __tpstrtab_##name, 0, reg, unreg, NULL }
+/*
+ * We have no guarantee that gcc and the linker won't up-align the tracepoint
+ * 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"))) =                      \
+                { __tpstrtab_##name, JUMP_LABEL_INIT, reg, unreg, NULL };\
+        static struct tracepoint * const __tracepoint_ptr_##name __used  \
+        __attribute__((section("__tracepoints_ptrs"))) =                 \
+                &__tracepoint_##name;
 
 #define DEFINE_TRACE(name)                                              \
         DEFINE_TRACE_FN(name, NULL, NULL);
@@ -183,7 +193,7 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
         EXPORT_SYMBOL(__tracepoint_##name)
 
 #else /* !CONFIG_TRACEPOINTS */
-#define __DECLARE_TRACE(name, proto, args, data_proto, data_args)       \
+#define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \
         static inline void trace_##name(proto)                          \
         { }                                                             \
         static inline int                                               \
@@ -224,13 +234,20 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
  * "void *__data, proto" as the callback prototype.
  */
 #define DECLARE_TRACE_NOARGS(name)                                      \
-                __DECLARE_TRACE(name, void, , void *__data, __data)
+                __DECLARE_TRACE(name, void, , 1, void *__data, __data)
 
 #define DECLARE_TRACE(name, proto, args)                                \
-                __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args),      \
+                __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1,   \
                                 PARAMS(void *__data, proto),            \
                                 PARAMS(__data, args))
 
+#define DECLARE_TRACE_CONDITION(name, proto, args, cond)                \
+        __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), PARAMS(cond), \
+                        PARAMS(void *__data, proto),                    \
+                        PARAMS(__data, args))
+
+#define TRACE_EVENT_FLAGS(event, flag)
+
 #endif /* DECLARE_TRACE */
 
 #ifndef TRACE_EVENT
@@ -312,7 +329,7 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
  *              memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN);
  *              __entry->next_pid       = next->pid;
  *              __entry->next_prio      = next->prio;
- *      )
+ *      ),
  *
  *      *
  *      * Formatted output of a trace record via TP_printk().
@@ -344,11 +361,21 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
         DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)  \
         DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
+#define DEFINE_EVENT_CONDITION(template, name, proto,           \
+                               args, cond)                      \
+        DECLARE_TRACE_CONDITION(name, PARAMS(proto),            \
+                                PARAMS(args), PARAMS(cond))
 
 #define TRACE_EVENT(name, proto, args, struct, assign, print)   \
         DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
 #define TRACE_EVENT_FN(name, proto, args, struct,               \
                 assign, print, reg, unreg)                      \
         DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
+#define TRACE_EVENT_CONDITION(name, proto, args, cond,          \
+                              struct, assign, print)            \
+        DECLARE_TRACE_CONDITION(name, PARAMS(proto),            \
+                                PARAMS(args), PARAMS(cond))
+
+#define TRACE_EVENT_FLAGS(event, flag)
 
 #endif /* ifdef TRACE_EVENT (see note above) */