tracepoint: Remove smp_read_barrier_depends() from comment (243d1a79) · Commits · 戴 / test

The comment in tracepoint_add_func() mentions smp_read_barrier_depends(), whose use should be quite restricted. This commit updates the comment to instead mention the smp_store_release() and rcu_dereference_sched() that the current code actually uses. Signed-off-by:

Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Acked-by:

Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by:

Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

kernel/tracepoint.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -212,11 +212,10 @@ static int tracepoint_add_func(struct tracepoint *tp,
		}

		/*
		* rcu_assign_pointer has a smp_wmb() which makes sure that the new
		* probe callbacks array is consistent before setting a pointer to it.
		* This array is referenced by __DO_TRACE from
		* include/linux/tracepoints.h. A matching smp_read_barrier_depends()
		* is used.
		* rcu_assign_pointer has as smp_store_release() which makes sure
		* that the new probe callbacks array is consistent before setting
		* a pointer to it. This array is referenced by __DO_TRACE from
		* include/linux/tracepoint.h using rcu_dereference_sched().
		*/
		rcu_assign_pointer(tp->funcs, tp_funcs);
		if (!static_key_enabled(&tp->key))

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