tracing: Fix return value of ftrace_raw_output_prep() (8e2e095c) · Commits · 戴 / test

If the trace_seq of ftrace_raw_output_prep() is full this function returns TRACE_TYPE_PARTIAL_LINE, otherwise it returns zero. The problem is that TRACE_TYPE_PARTIAL_LINE happens to be zero! The thing is, the caller of ftrace_raw_output_prep() expects a success to be zero. Change that to expect it to be TRACE_TYPE_HANDLED. Link: http://lkml.kernel.org/r/20141114112522.GA2988@dhcp128.suse.cz Reminded-by:

Petr Mladek <pmladek@suse.cz> Signed-off-by:

Steven Rostedt <rostedt@goodmis.org>

include/trace/ftrace.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -277,7 +277,7 @@ ftrace_raw_output_##call(struct trace_iterator *iter, int flags, \
		field = (typeof(field))iter->ent; \
		\
		ret = ftrace_raw_output_prep(iter, trace_event); \
		if (ret) \
		if (ret != TRACE_TYPE_HANDLED) \
		return ret; \
		\
		trace_seq_printf(s, print); \

kernel/trace/trace_output.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -196,10 +196,7 @@ int ftrace_raw_output_prep(struct trace_iterator *iter,
		trace_seq_init(p);
		trace_seq_printf(s, "%s: ", ftrace_event_name(event));

		if (trace_seq_has_overflowed(s))
		return TRACE_TYPE_PARTIAL_LINE;

		return 0;
		return trace_handle_return(s);
		}
		EXPORT_SYMBOL(ftrace_raw_output_prep);

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