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, 43 insertions, 0 deletions

diff --git a/tools/perf/util/pmus.h b/tools/perf/util/pmus.h
new file mode 100644
index 000000000..0d55edb3f
--- /dev/null
+++ b/tools/perf/util/pmus.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __PMUS_H
+#define __PMUS_H
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct perf_event_attr;
+struct perf_pmu;
+struct print_callbacks;
+
+size_t pmu_name_len_no_suffix(const char *str);
+/* Exposed for testing only. */
+int pmu_name_cmp(const char *lhs_pmu_name, const char *rhs_pmu_name);
+
+void perf_pmus__destroy(void);
+
+struct perf_pmu *perf_pmus__find(const char *name);
+struct perf_pmu *perf_pmus__find_by_type(unsigned int type);
+struct perf_pmu *perf_pmus__find_by_attr(const struct perf_event_attr *attr);
+
+struct perf_pmu *perf_pmus__scan(struct perf_pmu *pmu);
+struct perf_pmu *perf_pmus__scan_core(struct perf_pmu *pmu);
+struct perf_pmu *perf_pmus__scan_for_event(struct perf_pmu *pmu, const char *event);
+struct perf_pmu *perf_pmus__scan_matching_wildcard(struct perf_pmu *pmu, const char *wildcard);
+struct perf_pmu *perf_pmus__scan_for_uncore_id(struct perf_pmu *pmu, const char *compat);
+
+const struct perf_pmu *perf_pmus__pmu_for_pmu_filter(const char *str);
+
+void perf_pmus__print_pmu_events(const struct print_callbacks *print_cb, void *print_state);
+void perf_pmus__print_raw_pmu_events(const struct print_callbacks *print_cb, void *print_state);
+bool perf_pmus__have_event(const char *pname, const char *name);
+int perf_pmus__num_core_pmus(void);
+bool perf_pmus__supports_extended_type(void);
+
+struct perf_pmu *perf_pmus__add_test_pmu(int test_sysfs_dirfd, const char *name);
+struct perf_pmu *perf_pmus__add_test_hwmon_pmu(const char *hwmon_dir,
+					       const char *sysfs_name,
+					       const char *name);
+struct perf_pmu *perf_pmus__fake_pmu(void);
+struct perf_pmu *perf_pmus__find_core_pmu(void);
+
+#endif /* __PMUS_H */