linux/kernel/rcu
Linus Torvalds 7d9d077c78 RCU pull request for v5.20 (or whatever)
This pull request contains the following branches:
 
 doc.2022.06.21a: Documentation updates.
 
 fixes.2022.07.19a: Miscellaneous fixes.
 
 nocb.2022.07.19a: Callback-offload updates, perhaps most notably a new
 	RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to
 	be offloaded at boot time, regardless of kernel boot parameters.
 	This is useful to battery-powered systems such as ChromeOS
 	and Android.  In addition, a new RCU_NOCB_CPU_CB_BOOST kernel
 	boot parameter prevents offloaded callbacks from interfering
 	with real-time workloads and with energy-efficiency mechanisms.
 
 poll.2022.07.21a: Polled grace-period updates, perhaps most notably
 	making these APIs account for both normal and expedited grace
 	periods.
 
 rcu-tasks.2022.06.21a: Tasks RCU updates, perhaps most notably reducing
 	the CPU overhead of RCU tasks trace grace periods by more than
 	a factor of two on a system with 15,000 tasks.	The reduction
 	is expected to increase with the number of tasks, so it seems
 	reasonable to hypothesize that a system with 150,000 tasks might
 	see a 20-fold reduction in CPU overhead.
 
 torture.2022.06.21a: Torture-test updates.
 
 ctxt.2022.07.05a: Updates that merge RCU's dyntick-idle tracking into
 	context tracking, thus reducing the overhead of transitioning to
 	kernel mode from either idle or nohz_full userspace execution
 	for kernels that track context independently of RCU.  This is
 	expected to be helpful primarily for kernels built with
 	CONFIG_NO_HZ_FULL=y.
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Merge tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull RCU updates from Paul McKenney:

 - Documentation updates

 - Miscellaneous fixes

 - Callback-offload updates, perhaps most notably a new
   RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be
   offloaded at boot time, regardless of kernel boot parameters.

   This is useful to battery-powered systems such as ChromeOS and
   Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot
   parameter prevents offloaded callbacks from interfering with
   real-time workloads and with energy-efficiency mechanisms

 - Polled grace-period updates, perhaps most notably making these APIs
   account for both normal and expedited grace periods

 - Tasks RCU updates, perhaps most notably reducing the CPU overhead of
   RCU tasks trace grace periods by more than a factor of two on a
   system with 15,000 tasks.

   The reduction is expected to increase with the number of tasks, so it
   seems reasonable to hypothesize that a system with 150,000 tasks
   might see a 20-fold reduction in CPU overhead

 - Torture-test updates

 - Updates that merge RCU's dyntick-idle tracking into context tracking,
   thus reducing the overhead of transitioning to kernel mode from
   either idle or nohz_full userspace execution for kernels that track
   context independently of RCU.

   This is expected to be helpful primarily for kernels built with
   CONFIG_NO_HZ_FULL=y

* tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits)
  rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings
  rcu: Diagnose extended sync_rcu_do_polled_gp() loops
  rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings
  rcutorture: Test polled expedited grace-period primitives
  rcu: Add polled expedited grace-period primitives
  rcutorture: Verify that polled GP API sees synchronous grace periods
  rcu: Make Tiny RCU grace periods visible to polled APIs
  rcu: Make polled grace-period API account for expedited grace periods
  rcu: Switch polled grace-period APIs to ->gp_seq_polled
  rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty
  rcu/nocb: Add option to opt rcuo kthreads out of RT priority
  rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread()
  rcu/nocb: Add an option to offload all CPUs on boot
  rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call
  rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order
  rcu/nocb: Add/del rdp to iterate from rcuog itself
  rcu/tree: Add comment to describe GP-done condition in fqs loop
  rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs()
  rcu/kvfree: Remove useless monitor_todo flag
  rcu: Cleanup RCU urgency state for offline CPU
  ...
2022-08-02 19:12:45 -07:00
..
Kconfig Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00
Kconfig.debug rcu: Forbid RCU_STRICT_GRACE_PERIOD in TINY_RCU kernels 2022-07-19 11:39:59 -07:00
Makefile rcuperf: Change rcuperf to rcuscale 2020-08-24 18:39:24 -07:00
rcu_segcblist.c rcu: Clarify fill-the-gap comment in rcu_segcblist_advance() 2022-04-11 17:28:48 -07:00
rcu_segcblist.h rcu: Mark writes to the rcu_segcblist structure's ->flags field 2022-02-14 10:36:58 -08:00
rcu.h Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00
rcuscale.c rcuscale: Fix smp_processor_id()-in-preemptible warnings 2022-06-21 15:57:04 -07:00
rcutorture.c Merge branches 'doc.2022.06.21a', 'fixes.2022.07.19a', 'nocb.2022.07.19a', 'poll.2022.07.21a', 'rcu-tasks.2022.06.21a' and 'torture.2022.06.21a' into HEAD 2022-07-21 17:43:16 -07:00
refscale.c refscale: Convert test_lock spinlock to raw_spinlock 2022-06-21 15:57:04 -07:00
srcutiny.c srcu: Prevent redundant __srcu_read_unlock() wakeup 2021-11-30 17:28:16 -08:00
srcutree.c srcu: Make expedited RCU grace periods block even less frequently 2022-07-19 11:39:59 -07:00
sync.c rcu_sync: Fix comment to properly reflect rcu_sync_exit() behavior 2022-04-20 16:51:11 -07:00
tasks.h rcu-tasks: Use delayed_work to delay rcu_tasks_verify_self_tests() 2022-06-21 15:49:38 -07:00
tiny.c Merge branches 'doc.2022.06.21a', 'fixes.2022.07.19a', 'nocb.2022.07.19a', 'poll.2022.07.21a', 'rcu-tasks.2022.06.21a' and 'torture.2022.06.21a' into HEAD 2022-07-21 17:43:16 -07:00
tree_exp.h Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00
tree_nocb.h rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty 2022-07-19 11:43:55 -07:00
tree_plugin.h Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00
tree_stall.h RCU pull request for v5.20 (or whatever) 2022-08-02 19:12:45 -07:00
tree.c Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00
tree.h Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00
update.c Merge branch 'ctxt.2022.07.05a' into HEAD 2022-07-21 17:46:18 -07:00