Commit ee896ee8 authored Jul 27, 2020 by Vincent Whitchurch Committed by Steven Rostedt (VMware) Jul 30, 2020

tracing: Remove outdated comment in stack handling

This comment describes the behaviour before commit 2a820bf7
("tracing: Use percpu stack trace buffer more intelligently").  Since
that commit, interrupts and NMIs do use the per-cpu stacks so the
comment is no longer correct.  Remove it.

(Note that the FTRACE_STACK_SIZE mentioned in the comment has never
existed, it probably should have said FTRACE_STACK_ENTRIES.)

Link: https://lkml.kernel.org/r/20200727092840.18659-1-vincent.whitchurch@axis.com



Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

parent c5f51572

kernel/trace/trace.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -2930,12 +2930,6 @@ static void __ftrace_trace_stack(struct trace_buffer *buffer,
		skip++;
		#endif

		/*
		* Since events can happen in NMIs there's no safe way to
		* use the per cpu ftrace_stacks. We reserve it and if an interrupt
		* or NMI comes in, it will just have to use the default
		* FTRACE_STACK_SIZE.
		*/
		preempt_disable_notrace();

		stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1;

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