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, 156 insertions, 0 deletions

diff --git a/include/trace/events/intel-sst.h b/include/trace/events/intel-sst.h
new file mode 100644
index 000000000..0416e91f8
--- /dev/null
+++ b/include/trace/events/intel-sst.h
@@ -0,0 +1,156 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM intel-sst
+
+/*
+ * The TRACE_SYSTEM_VAR defaults to TRACE_SYSTEM, but must be a
+ * legitimate C variable. It is not exported to user space.
+ */
+#undef TRACE_SYSTEM_VAR
+#define TRACE_SYSTEM_VAR intel_sst
+
+#if !defined(_TRACE_INTEL_SST_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_INTEL_SST_H
+
+#include <linux/types.h>
+#include <linux/ktime.h>
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(sst_ipc_msg,
+
+	TP_PROTO(unsigned int val),
+
+	TP_ARGS(val),
+
+	TP_STRUCT__entry(
+		__field(	unsigned int,	val		)
+	),
+
+	TP_fast_assign(
+		__entry->val = val;
+	),
+
+	TP_printk("0x%8.8x", (unsigned int)__entry->val)
+);
+
+DEFINE_EVENT(sst_ipc_msg, sst_ipc_msg_tx,
+
+	TP_PROTO(unsigned int val),
+
+	TP_ARGS(val)
+
+);
+
+DEFINE_EVENT(sst_ipc_msg, sst_ipc_msg_rx,
+
+	TP_PROTO(unsigned int val),
+
+	TP_ARGS(val)
+
+);
+
+DECLARE_EVENT_CLASS(sst_ipc_mailbox,
+
+	TP_PROTO(unsigned int offset, unsigned int val),
+
+	TP_ARGS(offset, val),
+
+	TP_STRUCT__entry(
+		__field(	unsigned int,	offset		)
+		__field(	unsigned int,	val		)
+	),
+
+	TP_fast_assign(
+		__entry->offset = offset;
+		__entry->val = val;
+	),
+
+	TP_printk(" 0x%4.4x = 0x%8.8x",
+		(unsigned int)__entry->offset, (unsigned int)__entry->val)
+);
+
+DEFINE_EVENT(sst_ipc_mailbox, sst_ipc_inbox_rdata,
+
+	TP_PROTO(unsigned int offset, unsigned int val),
+
+	TP_ARGS(offset, val)
+
+);
+
+DEFINE_EVENT(sst_ipc_mailbox, sst_ipc_inbox_wdata,
+
+	TP_PROTO(unsigned int offset, unsigned int val),
+
+	TP_ARGS(offset, val)
+
+);
+
+DEFINE_EVENT(sst_ipc_mailbox, sst_ipc_outbox_rdata,
+
+	TP_PROTO(unsigned int offset, unsigned int val),
+
+	TP_ARGS(offset, val)
+
+);
+
+DEFINE_EVENT(sst_ipc_mailbox, sst_ipc_outbox_wdata,
+
+	TP_PROTO(unsigned int offset, unsigned int val),
+
+	TP_ARGS(offset, val)
+
+);
+
+DECLARE_EVENT_CLASS(sst_ipc_mailbox_info,
+
+	TP_PROTO(unsigned int size),
+
+	TP_ARGS(size),
+
+	TP_STRUCT__entry(
+		__field(	unsigned int,	size		)
+	),
+
+	TP_fast_assign(
+		__entry->size = size;
+	),
+
+	TP_printk("Mailbox bytes 0x%8.8x", (unsigned int)__entry->size)
+);
+
+DEFINE_EVENT(sst_ipc_mailbox_info, sst_ipc_inbox_read,
+
+	TP_PROTO(unsigned int size),
+
+	TP_ARGS(size)
+
+);
+
+DEFINE_EVENT(sst_ipc_mailbox_info, sst_ipc_inbox_write,
+
+	TP_PROTO(unsigned int size),
+
+	TP_ARGS(size)
+
+);
+
+DEFINE_EVENT(sst_ipc_mailbox_info, sst_ipc_outbox_read,
+
+	TP_PROTO(unsigned int size),
+
+	TP_ARGS(size)
+
+);
+
+DEFINE_EVENT(sst_ipc_mailbox_info, sst_ipc_outbox_write,
+
+	TP_PROTO(unsigned int size),
+
+	TP_ARGS(size)
+
+);
+
+#endif /* _TRACE_SST_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>