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, 35 insertions, 0 deletions

diff --git a/include/net/hwbm.h b/include/net/hwbm.h
new file mode 100644
index 000000000..bdbe91c60
--- /dev/null
+++ b/include/net/hwbm.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _HWBM_H
+#define _HWBM_H
+
+#include <linux/mutex.h>
+
+struct hwbm_pool {
+	/* Capacity of the pool */
+	int size;
+	/* Size of the buffers managed */
+	int frag_size;
+	/* Number of buffers currently used by this pool */
+	int buf_num;
+	/* constructor called during allocation */
+	int (*construct)(struct hwbm_pool *bm_pool, void *buf);
+	/* protect access to the buffer counter*/
+	struct mutex buf_lock;
+	/* private data */
+	void *priv;
+};
+#ifdef CONFIG_HWBM
+void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf);
+int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp);
+int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num);
+#else
+static inline void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf) {}
+
+static inline int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp)
+{ return 0; }
+
+static inline int hwbm_pool_add(struct hwbm_pool *bm_pool,
+				unsigned int buf_num)
+{ return 0; }
+#endif /* CONFIG_HWBM */
+#endif /* _HWBM_H */