Re: [PATCH] tracepoint: Do not fail unregistering a probe due to memory allocation

[Steven Rostedt]

On Tue, 17 Nov 2020 16:22:23 -0500 (EST)
Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> wrote:

> If we don't call the stub, then there is no point in having the stub at
> all, and we should just compare to a constant value, e.g. 0x1UL. As far
> as I can recall, comparing with a small immediate constant is more efficient
> than comparing with a loaded value on many architectures.

Why 0x1UL, and not just set it to NULL.

		do {							\
			it_func = (it_func_ptr)->func;			\
			__data = (it_func_ptr)->data;			\
			if (likely(it_func))				\
				((void(*)(void *, proto))(it_func))(__data, args); \
		} while ((++it_func_ptr)->func);


-- Steve