Commit 0e6caab8 authored by Mathieu Desnoyers's avatar Mathieu Desnoyers Committed by Steven Rostedt (Google)
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tracing: Declare system call tracepoints with TRACE_EVENT_SYSCALL 

In preparation for allowing system call tracepoints to handle page
faults, introduce TRACE_EVENT_SYSCALL to declare the sys_enter/sys_exit
tracepoints.

Move the common code between __DECLARE_TRACE and __DECLARE_TRACE_SYSCALL
into __DECLARE_TRACE_COMMON.

This change is not meant to alter the generated code, and only prepares
the following modifications.

Cc: Michael Jeanson <mjeanson@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>
Link: https://lore.kernel.org/20241009010718.2050182-2-mathieu.desnoyers@efficios.com


Signed-off-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent e53244e2

include/linux/tracepoint.h

+40 −13
Original line number Diff line number Diff line
@@ -197,7 +197,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
 * it_func[0] is never NULL because there is at least one element in the array

 * when the array itself is non NULL.

 */

#define __DO_TRACE(name, args, cond)					\

#define __DO_TRACE(name, args, cond, syscall)				\

	do {								\

		int __maybe_unused __idx = 0;				\

									\
@@ -222,21 +222,10 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
 * site if it is not watching, as it will need to be active when the

 * tracepoint is enabled.

 */

#define __DECLARE_TRACE(name, proto, args, cond, data_proto)		\

#define __DECLARE_TRACE_COMMON(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_branch_unlikely(&__tracepoint_##name.key))	\

			__DO_TRACE(name,				\

				TP_ARGS(args),				\

				TP_CONDITION(cond));			\

		if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) {		\

			WARN_ONCE(!rcu_is_watching(),			\

				  "RCU not watching for tracepoint");	\

		}							\

	}								\

	static inline int						\

	register_trace_##name(void (*probe)(data_proto), void *data)	\

	{								\
@@ -266,6 +255,34 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
		return static_branch_unlikely(&__tracepoint_##name.key);\

	}



#define __DECLARE_TRACE(name, proto, args, cond, data_proto)		\

	__DECLARE_TRACE_COMMON(name, PARAMS(proto), PARAMS(args), cond, PARAMS(data_proto)) \

	static inline void trace_##name(proto)				\

	{								\

		if (static_branch_unlikely(&__tracepoint_##name.key))	\

			__DO_TRACE(name,				\

				TP_ARGS(args),				\

				TP_CONDITION(cond), 0);			\

		if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) {		\

			WARN_ONCE(!rcu_is_watching(),			\

				  "RCU not watching for tracepoint");	\

		}							\

	}



#define __DECLARE_TRACE_SYSCALL(name, proto, args, cond, data_proto)	\

	__DECLARE_TRACE_COMMON(name, PARAMS(proto), PARAMS(args), cond, PARAMS(data_proto)) \

	static inline void trace_##name(proto)				\

	{								\

		if (static_branch_unlikely(&__tracepoint_##name.key))	\

			__DO_TRACE(name,				\

				TP_ARGS(args),				\

				TP_CONDITION(cond), 1);			\

		if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) {		\

			WARN_ONCE(!rcu_is_watching(),			\

				  "RCU not watching for tracepoint");	\

		}							\

	}



/*

 * 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
@@ -348,6 +365,8 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
		return false;						\

	}



#define __DECLARE_TRACE_SYSCALL	__DECLARE_TRACE



#define DEFINE_TRACE_FN(name, reg, unreg, proto, args)

#define DEFINE_TRACE(name, proto, args)

#define EXPORT_TRACEPOINT_SYMBOL_GPL(name)
@@ -409,6 +428,11 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
			cpu_online(raw_smp_processor_id()) && (PARAMS(cond)), \

			PARAMS(void *__data, proto))



#define DECLARE_TRACE_SYSCALL(name, proto, args)			\

	__DECLARE_TRACE_SYSCALL(name, PARAMS(proto), PARAMS(args),	\

				cpu_online(raw_smp_processor_id()),	\

				PARAMS(void *__data, proto))



#define TRACE_EVENT_FLAGS(event, flag)



#define TRACE_EVENT_PERF_PERM(event, expr...)
@@ -546,6 +570,9 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
			      struct, assign, print)		\

	DECLARE_TRACE_CONDITION(name, PARAMS(proto),		\

				PARAMS(args), PARAMS(cond))

#define TRACE_EVENT_SYSCALL(name, proto, args, struct, assign,	\

			    print, reg, unreg)			\

	DECLARE_TRACE_SYSCALL(name, PARAMS(proto), PARAMS(args))



#define TRACE_EVENT_FLAGS(event, flag)

include/trace/bpf_probe.h

+3 −0
Original line number Diff line number Diff line
@@ -53,6 +53,9 @@ __bpf_trace_##call(void *__data, proto) \ 
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\

	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))



#undef DECLARE_EVENT_SYSCALL_CLASS

#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS



/*

 * This part is compiled out, it is only here as a build time check

 * to make sure that if the tracepoint handling changes, the

include/trace/define_trace.h

+5 −0
Original line number Diff line number Diff line
@@ -46,6 +46,10 @@ 
		assign, print, reg, unreg)			\

	DEFINE_TRACE_FN(name, reg, unreg, PARAMS(proto), PARAMS(args))



#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))



#undef TRACE_EVENT_NOP

#define TRACE_EVENT_NOP(name, proto, args, struct, assign, print)
@@ -107,6 +111,7 @@ 
#undef TRACE_EVENT

#undef TRACE_EVENT_FN

#undef TRACE_EVENT_FN_COND

#undef TRACE_EVENT_SYSCALL

#undef TRACE_EVENT_CONDITION

#undef TRACE_EVENT_NOP

#undef DEFINE_EVENT_NOP

include/trace/events/syscalls.h

+2 −2
Original line number Diff line number Diff line
@@ -15,7 +15,7 @@ 


#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS



TRACE_EVENT_FN(sys_enter,

TRACE_EVENT_SYSCALL(sys_enter,



	TP_PROTO(struct pt_regs *regs, long id),
@@ -41,7 +41,7 @@ TRACE_EVENT_FN(sys_enter, 


TRACE_EVENT_FLAGS(sys_enter, TRACE_EVENT_FL_CAP_ANY)



TRACE_EVENT_FN(sys_exit,

TRACE_EVENT_SYSCALL(sys_exit,



	TP_PROTO(struct pt_regs *regs, long ret),

include/trace/perf.h

+3 −0
Original line number Diff line number Diff line
@@ -55,6 +55,9 @@ perf_trace_##call(void *__data, proto) \ 
				  head, __task);			\

}



#undef DECLARE_EVENT_SYSCALL_CLASS

#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS



/*

 * This part is compiled out, it is only here as a build time check

 * to make sure that if the tracepoint handling changes, the