Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ftrace: Comment that ftrace_func_mapper is freed with free_ftrace_hash()
The structure ftrace_func_mapper only contains a single field and that is
a ftrace_hash. It is used to abstract it out from a normal hash to control
users of how it gets modified.
The freeing of a ftrace_func_mapper structure is:
free_ftrace_hash(&mapper->hash);
Without context, this looks like a bug. It should be commented that it is
not a bug and it is freed this way.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20250416165420.5c717420@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
+6
-1
+6
-1
kernel/trace/ftrace.c
+6
-1
kernel/trace/ftrace.c
···
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void *data;
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};
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+
/*
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* Note, ftrace_func_mapper is freed by free_ftrace_hash(&mapper->hash).
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* The hash field must be the first field.
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+
*/
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struct ftrace_func_mapper {
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-
struct ftrace_hash hash;
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+
struct ftrace_hash hash; /* Must be first! */
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};
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/**
···
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}
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}
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}
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+
/* This also frees the mapper itself */
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free_ftrace_hash(&mapper->hash);
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}
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