Re: [PATCH v2] doc: Update recent RCU/SRCU API additions to whatisRCU.rst

[Bradley Morgan <brads@mainlining.org>]

On 19 October 2026 13:22:09 BST, Zqiang <qiang.zhang@linux.dev> wrote:
>The following commit introduces some new RCU/SRCU APIs:
>
>Commit 'd3f52f53a562 ("srcu: Create an SRCU-fast-updown API")'
>Commit 'dab06d6f9379 ("srcutree: Add an atomic Tree SRCU")'
>Commit 'cacadb630375 ("srcu: Add guards for notrace variants of SRCU-fast
>readers")'
>Commit 'fa8a2d55139f ("srcu: Add lock guard for srcu_fast_updown flavor")'
>Commit '954c0d741299 ("srcu: Add guards for SRCU-fast readers")'
>
>This commit therefore update thems and some missing RCU related APIs
>to whatisRCU.rst.
>

Since this relates to my patch, and it looks good:

Acked-by: Bradley Morgan <brads@mainlining.org>


>Signed-off-by: Zqiang <qiang.zhang@linux.dev>
>---
> Documentation/RCU/whatisRCU.rst | 24 +++++++++++++++++++++---
> 1 file changed, 21 insertions(+), 3 deletions(-)
>
>diff --git a/Documentation/RCU/whatisRCU.rst b/Documentation/RCU/whatisRCU.rst
>index e6767baff2d3..fe9dc3948690 100644
>--- a/Documentation/RCU/whatisRCU.rst
>+++ b/Documentation/RCU/whatisRCU.rst
>@@ -1084,8 +1084,9 @@ RCU::
> 	rcu_dereference			call_rcu
> 	rcu_dereference_check		call_rcu_hurry
> 	rcu_dereference_protected	kfree_rcu
>-	rcu_read_lock_held		kvfree_rcu
>-	rcu_read_lock_any_held		kfree_rcu_mightsleep
>+	rcu_dereference_all		kvfree_rcu
>+	rcu_read_lock_held		kfree_rcu_mightsleep
>+	rcu_read_lock_any_held		kvfree_rcu_mightsleep
> 	rcu_pointer_handoff		cond_synchronize_rcu
> 	unrcu_pointer			cond_synchronize_rcu_full
> 					cond_synchronize_rcu_expedited
>@@ -1209,13 +1210,23 @@ SRCU::
> 	srcu_read_lock_nmisafe		start_poll_synchronize_srcu
> 	srcu_read_unlock_nmisafe	start_poll_synchronize_srcu_expedited
> 	srcu_read_lock_notrace		poll_state_synchronize_srcu
>-	srcu_read_unlock_notrace
>+	srcu_read_unlock_notrace	synchronize_srcu_atomic
> 	srcu_down_read
> 	srcu_up_read
> 	srcu_down_read_fast
> 	srcu_up_read_fast
>+	srcu_read_lock_fast_updown
>+	srcu_read_unlock_fast_updown
>+	srcu_read_lock_atomic
>+	srcu_read_unlock_atomic
> 	guard(srcu)()
>+	guard(srcu_fast)()
>+	guard(srcu_fast_notrace)()
>+	guard(srcu_fast_updown)()
> 	scoped_guard(srcu)
>+	scoped_guard(srcu_fast)
>+	scoped_guard(srcu_fast_notrace)
>+	scoped_guard(srcu_fast_updown)
> 	srcu_read_lock_held
> 	srcu_dereference
> 	srcu_dereference_check
>@@ -1229,9 +1240,16 @@ SRCU: Initialization/cleanup/ordering::
> 	DEFINE_STATIC_SRCU
> 	DEFINE_SRCU_FAST        // for srcu_read_lock_fast() and friends
> 	DEFINE_STATIC_SRCU_FAST // for srcu_read_lock_fast() and friends
>+	DEFINE_SRCU_FAST_UPDOWN		// for srcu_read_lock_fast_updown() and friends
>+	DEFINE_STATIC_SRCU_FAST_UPDOWN	// for srcu_read_lock_fast_updown() and friends
>+	DEFINE_SRCU_ATOMIC		// for srcu_read_lock_atomic() and friends
>+	DEFINE_STATIC_SRCU_ATOMIC	// for srcu_read_lock_atomic() and friends
> 	init_srcu_struct
> 	init_srcu_struct_fast
>+	init_srcu_struct_fast_updown
>+	init_srcu_struct_atomic
> 	cleanup_srcu_struct
>+	smp_mb__after_srcu_read_lock
> 	smp_mb__after_srcu_read_unlock
> 
> All: lockdep-checked RCU utility APIs::
>

--- Thanks!
"I'm not a very positive person" - Linus torvalds