Commit 306d40aa authored Nov 23, 2024 by Mathieu Desnoyers Committed by Steven Rostedt (Google) Nov 23, 2024

tracing: Move it_func[0] comment to the relevant context

When introducing __DO_TRACE_CALL(), the iteration over it_func moved
from __DO_TRACE() to __tracepoint_iter_##_name(), but the comment
relevant for this iterator was left in its original location.

Move the comment to the relevant context.

Fixes: d25e37d8 ("tracepoint: Optimize using static_call()")
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
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>
Cc: Jordan Rife <jrife@google.com>
Link: https://lore.kernel.org/20241123153031.2884933-2-mathieu.desnoyers@efficios.com

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

parent 0172afef

include/linux/tracepoint.h

+3 −3

Original line number	Diff line number	Diff line
		@@ -210,9 +210,6 @@ static inline struct tracepoint tracepoint_ptr_deref(tracepoint_ptr_t p)
		#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.
		*
		* With @syscall=0, the tracepoint callback array dereference is
		* protected by disabling preemption.
		* With @syscall=1, the tracepoint callback array dereference is
		@@ -316,6 +313,9 @@ static inline struct tracepoint tracepoint_ptr_deref(tracepoint_ptr_t p)
		* 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.
		*
		* it_func[0] is never NULL because there is at least one element in the array
		* when the array itself is non NULL.
		*/
		#define __DEFINE_TRACE_EXT(_name, _ext, proto, args) \
		static const char __tpstrtab_##_name[] \