Commit 729fb748 authored Jan 17, 2025 by Paul E. McKenney Committed by Boqun Feng Feb 05, 2025

srcu: Document that srcu_{read_lock,down_read}() can share srcu_struct

This commit adds a sentence to the srcu_down_read() function's kernel-doc
header noting that it is permissible to use srcu_down_read() and
srcu_read_lock() on the same srcu_struct, even concurrently.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: <bpf@vger.kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>

parent dfe442c9

include/linux/srcu.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -359,7 +359,8 @@ srcu_read_lock_notrace(struct srcu_struct *ssp) __acquires(ssp)
		* srcu_down_read() nor srcu_up_read() may be invoked from an NMI handler.
		*
		* Calls to srcu_down_read() may be nested, similar to the manner in
		* which calls to down_read() may be nested.
		* which calls to down_read() may be nested. The same srcu_struct may be
		* used concurrently by srcu_down_read() and srcu_read_lock().
		*/
		static inline int srcu_down_read(struct srcu_struct *ssp) __acquires(ssp)
		{