linux/kernel/rcu
Linus Torvalds 83684c4e4d RCU updates:
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.
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Merge tag 'rcu.2026.08.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux

Pull RCU updates from Paul McKenney:
 "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"

* tag 'rcu.2026.08.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (59 commits)
  rcu: Add closing parenthesis in comment in rcu_read_unlock_strict()
  rcutorture: Make {,s}rcu_read_delay() better handle forward-progress testing
  rcutorture: Announce declining to forward-progress test
  torture: Don't leak shuffle_tmp_mask when shuffler kthread fails to start
  rcutorture: Use this_cpu_inc() for rcu_torture_count[] and rcu_torture_batch[]
  rcutorture: Make RCU Tasks Trace track Reader Batches
  rcutorture: Test RCU Tasks Trace GP implying RCU GP
  rcutorture: Add a stall_only module parameter
  rcutorture: Add nwriters module parameter
  rcutorture: Use task_state_to_char() for task-state reporting
  rcutorture: Use cpumask_next_wrap() in rcu_torture_preempt()
  rcutorture: Test RCU readers from hardware interrupt handlers
  rcutorture: Check for immediate deboosting at reader end
  srcu: Queue sdp->work when the delay timer is successfully deleted
  rcu-tasks: Convert cond_resched_tasks_rcu_qs() to static inline
  rcu-tasks: Fix some comments for call_rcu_tasks() and call_rcu_tasks_rude()
  rcu-tasks: Rename tasks_rcu_exit_srcu_stall_timer to tasks_rcu_exit_stall_timer
  rcu: Mark interrupts-enabled accesses to rdp->cpu_no_qs.s
  rcu: Reduce stack usage in show_rcu_gp_kthreads()
  rcu: Mark accesses to ->rcu_urgent_qs and ->rcu_need_heavy_qs
  ...
2026-08-23 18:00:22 -07:00
..
Kconfig rcu-tasks: TASKS_TRACE_RCU doesn't need IRQ_WORK 2026-07-15 15:28:41 -07:00
Kconfig.debug RCU changes for v7.1 2026-04-13 09:36:45 -07:00
Makefile rcuperf: Change rcuperf to rcuscale 2020-08-24 18:39:24 -07:00
rcu_segcblist.c rcu: Update comments for gp_seq and expedited GP tracking 2026-07-24 16:54:07 -07:00
rcu_segcblist.h rcu: Enable RCU callbacks to benefit from expedited grace periods 2026-07-24 16:52:56 -07:00
rcu.h 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 HEAD 2026-08-14 15:43:51 -07:00
rcuscale.c rcuscale: Add concurrent expedited GP threads for callback scaling tests 2026-07-24 16:57:29 -07:00
rcutorture.c 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 HEAD 2026-08-14 15:43:51 -07:00
refscale.c refscale: Ditch ref_scale_shutdown in favor of torture_shutdown_init() 2026-03-30 15:48:13 -04:00
srcutiny.c srcu: expose srcu_readers_active() 2026-07-15 15:34:25 -07:00
srcutree.c 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 HEAD 2026-08-14 15:43:51 -07:00
sync.c rcu: Eliminate lockless accesses to rcu_sync->gp_count 2024-07-04 13:48:57 -07:00
tasks.h 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 HEAD 2026-08-14 15:43:51 -07:00
tiny.c rcu: Rename struct rcu_gp_oldstate to rcu_gp_seq 2026-07-23 10:46:09 -07:00
tree_exp.h RCU updates: 2026-08-23 18:00:22 -07:00
tree_nocb.h 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 HEAD 2026-08-14 15:43:51 -07:00
tree_plugin.h 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 HEAD 2026-08-14 15:43:51 -07:00
tree_stall.h RCU updates: 2026-08-23 18:00:22 -07:00
tree.c RCU updates: 2026-08-23 18:00:22 -07:00
tree.h 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 HEAD 2026-08-14 15:43:51 -07:00
update.c rcutorture: Add a textbook-style trivial preemptible RCU 2026-03-30 15:48:13 -04:00