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, 86 insertions, 0 deletions

diff --git a/include/sound/seq_device.h b/include/sound/seq_device.h
new file mode 100644
index 000000000..3137d4c5f
--- /dev/null
+++ b/include/sound/seq_device.h
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __SOUND_SEQ_DEVICE_H
+#define __SOUND_SEQ_DEVICE_H
+
+/*
+ *  ALSA sequencer device management
+ *  Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de>
+ */
+
+/*
+ * registered device information
+ */
+
+struct snd_seq_device {
+	/* device info */
+	struct snd_card *card;	/* sound card */
+	int device;		/* device number */
+	const char *id;		/* driver id */
+	char name[80];		/* device name */
+	int argsize;		/* size of the argument */
+	void *driver_data;	/* private data for driver */
+	void *private_data;	/* private data for the caller */
+	void (*private_free)(struct snd_seq_device *device);
+	struct device dev;
+	unsigned char args[];	/* driver-specific argument */
+};
+
+#define to_seq_dev(_dev) \
+	container_of(_dev, struct snd_seq_device, dev)
+
+/* sequencer driver */
+
+/* driver operators
+ * probe:
+ *	Initialize the device with given parameters.
+ *	Typically,
+ *		1. call snd_hwdep_new
+ *		2. allocate private data and initialize it
+ *		3. call snd_hwdep_register
+ *		4. store the instance to dev->driver_data pointer.
+ *		
+ * remove:
+ *	Release the private data.
+ *	Typically, call snd_device_free(dev->card, dev->driver_data)
+ */
+struct snd_seq_driver {
+	int (*probe)(struct snd_seq_device *dev);
+	void (*remove)(struct snd_seq_device *dev);
+	struct device_driver driver;
+	char *id;
+	int argsize;
+};
+
+#define to_seq_drv(_drv) \
+	container_of(_drv, struct snd_seq_driver, driver)
+
+/*
+ * prototypes
+ */
+#ifdef CONFIG_MODULES
+void snd_seq_device_load_drivers(void);
+#else
+#define snd_seq_device_load_drivers()
+#endif
+int snd_seq_device_new(struct snd_card *card, int device, const char *id,
+		       int argsize, struct snd_seq_device **result);
+
+#define SNDRV_SEQ_DEVICE_ARGPTR(dev) ((void *)(dev)->args)
+
+int __must_check __snd_seq_driver_register(struct snd_seq_driver *drv,
+					   struct module *mod);
+#define snd_seq_driver_register(drv) \
+	__snd_seq_driver_register(drv, THIS_MODULE)
+void snd_seq_driver_unregister(struct snd_seq_driver *drv);
+
+#define module_snd_seq_driver(drv) \
+	module_driver(drv, snd_seq_driver_register, snd_seq_driver_unregister)
+
+/*
+ * id strings for generic devices
+ */
+#define SNDRV_SEQ_DEV_ID_MIDISYNTH	"seq-midi"
+#define SNDRV_SEQ_DEV_ID_OPL3		"opl3-synth"
+#define SNDRV_SEQ_DEV_ID_UMP		"seq-ump-client"
+
+#endif /* __SOUND_SEQ_DEVICE_H */