ftrace: Add recording of functions that caused recursion

This adds CONFIG_FTRACE_RECORD_RECURSION that will record to a file "recursed_functions" all the functions that caused recursion while a callback to the function tracer was running. Link: https://lkml.kernel.org/r/20201106023548.102375687@goodmis.org

Steven Rostedt (VMware) committed 6 years ago

Commit 773c1671 parent a25d03617 files · +306 −20Browse files

Showing the changes to kernel/livepatch/patch.c (1 of 17 files). Show all

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kernel/livepatch/patch.c+1−1

@@ -49,7 +49,7 @@ static void notrace klp_ftrace_handler(unsigned long ip, · 48 unmodified lines
49		49
50	ops = container_of(fops, struct klp_ops, fops);	50	ops = container_of(fops, struct klp_ops, fops);
51		51
52	bit = ftrace_test_recursion_trylock();	52	bit = ftrace_test_recursion_trylock(ip, parent_ip);
53	if (WARN_ON_ONCE(bit < 0))	53	if (WARN_ON_ONCE(bit < 0))
54	return;	54	return;
55	/*	55	/*