Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEADgrafted

Changes:

Make expedited grace periods expedite normal RCU callbacks

Miscellaneous fixes:
 * Improve diagnostic output with character task states.
 * Mark accesses to inform KCSAN of concurrency design.
 * Move from kmalloc() to kmalloc_obj().
 * Documentation updates.
 * Improve handling of RCU deferred quiescent states.
 * Clean up unused function arguments and structure fields.
 * Reduce show_rcu_gp_kthreads() stack space.

Tasks RCU updates:
 * Clean up after SRCU re-implementation of Tasks Trace RCU.
 * Mark accesses to inform KCSAN of concurrency design.
 * Add ->lazy_timer status to diagnostic output.
 * Remove an unnecessary memory barrier.
 * Fix a data race, courtesy of KCSAN.
 * Documentation updates.
 * Convert cond_resched_tasks_rcu_qs() from macro to static inline
   function.

SRCU updates:
 * Add Rust helpers for SRCU.
 * Avoid losing queued work at cleanup_srcu_struct() time.

Torture-test updates:
 * Preparation work for immediate RCU priority deboosting.
 * Test RCU readers from real interrupt handlers (as opposed to softirq).
 * Simplify code through use of cpumask_next_wrap().
 * Improve diagnostic output with character task states.
 * Add rcutorture.nwriters parameter to allow lightweight stall testing,
   and rcutorture.stall_only to make doing so easier.
 * Test an RCU Tasks Trace grace period implying an RCU grace period.
 * Make RCU Tasks Trace torturing track reader batches.
 * Fix a data race, courtesy of KCSAN.
 * Plug a shuffle_tmp_mask memory leak on kthread spawn failure.

1 files changed, 30 insertions, 0 deletions

diff --git a/net/dcb/dcbevent.c b/net/dcb/dcbevent.c
new file mode 100644
index 000000000..8620564c2
--- /dev/null
+++ b/net/dcb/dcbevent.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2010, Intel Corporation.
+ *
+ * Author: John Fastabend <john.r.fastabend@intel.com>
+ */
+
+#include <linux/rtnetlink.h>
+#include <linux/notifier.h>
+#include <linux/export.h>
+#include <net/dcbevent.h>
+
+static ATOMIC_NOTIFIER_HEAD(dcbevent_notif_chain);
+
+int register_dcbevent_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&dcbevent_notif_chain, nb);
+}
+EXPORT_SYMBOL(register_dcbevent_notifier);
+
+int unregister_dcbevent_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(&dcbevent_notif_chain, nb);
+}
+EXPORT_SYMBOL(unregister_dcbevent_notifier);
+
+int call_dcbevent_notifiers(unsigned long val, void *v)
+{
+	return atomic_notifier_call_chain(&dcbevent_notif_chain, val, v);
+}