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.

2 files changed, 85 insertions, 0 deletions

diff --git a/tools/perf/trace/strace/groups/file b/tools/perf/trace/strace/groups/file
new file mode 100644
index 000000000..722e25d20
--- /dev/null
+++ b/tools/perf/trace/strace/groups/file
@@ -0,0 +1,20 @@
+access
+chmod
+creat
+execve
+faccessat
+getcwd
+lstat
+mkdir
+open
+openat
+quotactl
+read
+readlink
+rename
+rmdir
+stat
+statfs
+symlink
+unlink
+write
diff --git a/tools/perf/trace/strace/groups/string b/tools/perf/trace/strace/groups/string
new file mode 100644
index 000000000..c87129a3e
--- /dev/null
+++ b/tools/perf/trace/strace/groups/string
@@ -0,0 +1,65 @@
+access
+acct
+add_key
+chdir
+chmod
+chown
+chroot
+creat
+delete_module
+execve
+execveat
+faccessat
+fchmodat
+fchownat
+fgetxattr
+finit_module
+fremovexattr
+fsetxattr
+futimesat
+getxattr
+inotify_add_watch
+lchown
+lgetxattr
+link
+linkat
+listxattr
+llistxattr
+lremovexattr
+lsetxattr
+lstat
+memfd_create
+mkdir
+mkdirat
+mknod
+mknodat
+mq_open
+mq_timedsend
+mq_unlink
+name_to_handle_at
+newfstatat
+open
+openat
+pivot_root
+pwrite64
+quotactl
+readlink
+readlinkat
+removexattr
+rename
+renameat
+renameat2
+request_key
+rmdir
+setxattr
+stat
+statfs
+statx
+swapoff
+swapon
+symlink
+symlinkat
+truncate
+unlink
+unlinkat
+utimensat