rcu-tasks: Always inline rcu_irq_work_resched()

Thanks to CONFIG_DEBUG_SECTION_MISMATCH, empty functions can be
generated out of line. rcu_irq_work_resched() can be called from
noinstr code, so mak

rcu-tasks: Always inline rcu_irq_work_resched()

Thanks to CONFIG_DEBUG_SECTION_MISMATCH, empty functions can be
generated out of line. rcu_irq_work_resched() can be called from
noinstr code, so make sure it's always inlined.

Fixes: 564506495ca9 ("rcu/context-tracking: Move deferred nocb resched to context tracking")
Reported-by: Randy Dunlap <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/e84f15f013c07e4c410d972e75620c53b62c1b3e.1743481539.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/[email protected]

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rcu-tasks: Move RCU Tasks self-tests to core_initcall()

The timer and hrtimer softirq processing has moved to dedicated threads
for kernels built with CONFIG_IRQ_FORCED_THREADING=y. This results in

rcu-tasks: Move RCU Tasks self-tests to core_initcall()

The timer and hrtimer softirq processing has moved to dedicated threads
for kernels built with CONFIG_IRQ_FORCED_THREADING=y. This results in
timers not expiring until later in early boot, which in turn causes the
RCU Tasks self-tests to hang in kernels built with CONFIG_PROVE_RCU=y,
which further causes the entire kernel to hang. One fix would be to
make timers work during this time, but there are no known users of RCU
Tasks grace periods during that time, so no justification for the added
complexity. Not yet, anyway.

This commit therefore moves the call to rcu_init_tasks_generic() from
kernel_init_freeable() to a core_initcall(). This works because the
timer and hrtimer kthreads are created at early_initcall() time.

Fixes: 49a17639508c3 ("softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.")
Signed-off-by: Paul E. McKenney <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: <[email protected]>
Tested-by: Sebastian Andrzej Siewior <[email protected]>
Reviewed-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Boqun Feng <[email protected]>

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rcu: handle unstable rdp in rcu_read_unlock_strict()

rcu_read_unlock_strict() can be called with preemption enabled
which can make for an unstable rdp and a racy norm value.

Fix this by dropping th

rcu: handle unstable rdp in rcu_read_unlock_strict()

rcu_read_unlock_strict() can be called with preemption enabled
which can make for an unstable rdp and a racy norm value.

Fix this by dropping the preempt-count in __rcu_read_unlock()
after the call to rcu_read_unlock_strict(), adjusting the
preempt-count check appropriately.

Suggested-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Ankur Arora <[email protected]>
Reviewed-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Boqun Feng <[email protected]>

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rcu, slab: use a regular callback function for kvfree_rcu

RCU has been special-casing callback function pointers that are integers
lower than 4096 as offsets of rcu_head for kvfree() instead. The tr

rcu, slab: use a regular callback function for kvfree_rcu

RCU has been special-casing callback function pointers that are integers
lower than 4096 as offsets of rcu_head for kvfree() instead. The tree
RCU implementation no longer does that as the batched kvfree_rcu() is
not a simple call_rcu(). The tiny RCU still does, and the plan is also
to make tree RCU use call_rcu() for SLUB_TINY configurations.

Instead of teaching tree RCU again to special case the offsets, let's
remove the special casing completely. Since there's no SLOB anymore, it
is possible to create a callback function that can take a pointer to a
middle of slab object with unknown offset and determine the object's
pointer before freeing it, so implement that as kvfree_rcu_cb().

Large kmalloc and vmalloc allocations are handled simply by aligning
down to page size. For that we retain the requirement that the offset is
smaller than 4096. But we can remove __is_kvfree_rcu_offset() completely
and instead just opencode the condition in the BUILD_BUG_ON() check.

Reviewed-by: Joel Fernandes (Google) <[email protected]>
Reviewed-by: Hyeonggon Yoo <[email protected]>
Tested-by: Paul E. McKenney <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>

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slab, rcu: move TINY_RCU variant of kvfree_rcu() to SLAB

Following the move of TREE_RCU implementation, let's move also the
TINY_RCU one for consistency and subsequent refactoring.

For simplicity,

slab, rcu: move TINY_RCU variant of kvfree_rcu() to SLAB

Following the move of TREE_RCU implementation, let's move also the
TINY_RCU one for consistency and subsequent refactoring.

For simplicity, remove the separate inline __kvfree_call_rcu() as
TINY_RCU is not meant for high-performance hardware anyway.

Declare kvfree_call_rcu() in rcupdate.h to avoid header dependency
issues.

Also move the kvfree_rcu_barrier() declaration to slab.h

Reviewed-by: Uladzislau Rezki (Sony) <[email protected]>
Reviewed-by: Joel Fernandes (Google) <[email protected]>
Reviewed-by: Hyeonggon Yoo <[email protected]>
Tested-by: Paul E. McKenney <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>

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rcu: Remove references to old grace-period-wait primitives

The rcu_barrier_sched(), synchronize_sched(), and synchronize_rcu_bh()
RCU API members have been gone for many years. This commit therefor

rcu: Remove references to old grace-period-wait primitives

The rcu_barrier_sched(), synchronize_sched(), and synchronize_rcu_bh()
RCU API members have been gone for many years. This commit therefore
removes non-historical instances of them.

Reported-by: Joe Perches <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Boqun Feng <[email protected]>

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mm/slab: Move kvfree_rcu() into SLAB

Move kvfree_rcu() functionality to the slab_common.c file.

The reason to have kvfree_rcu() functionality as part of SLAB is that
there is a clear trend and need

mm/slab: Move kvfree_rcu() into SLAB

Move kvfree_rcu() functionality to the slab_common.c file.

The reason to have kvfree_rcu() functionality as part of SLAB is that
there is a clear trend and need of closer integration. One of the recent
example is creating a barrier function for SLAB caches.

Another reason is to prevent of having several implementations of RCU
machinery for reclaiming objects after a GP. As future steps, it can be
more integrated(easier) with SLAB internals.

Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>
Acked-by: Hyeonggon Yoo <[email protected]>
Tested-by: Hyeonggon Yoo <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>

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rcu/kvfree: Initialize kvfree_rcu() separately

Introduce a separate initialization of kvfree_rcu() functionality.
For such purpose a kfree_rcu_batch_init() is renamed to a kvfree_rcu_init()
and it i

rcu/kvfree: Initialize kvfree_rcu() separately

Introduce a separate initialization of kvfree_rcu() functionality.
For such purpose a kfree_rcu_batch_init() is renamed to a kvfree_rcu_init()
and it is invoked from the main.c right after rcu_init() is done.

Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>
Acked-by: Hyeonggon Yoo <[email protected]>
Tested-by: Hyeonggon Yoo <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>

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Rename .data.unlikely to .data..unlikely

Commit 7ccaba5314ca ("consolidate WARN_...ONCE() static variables")
was intended to collect all .data.unlikely sections into one chunk.
However, this has not

Rename .data.unlikely to .data..unlikely

Commit 7ccaba5314ca ("consolidate WARN_...ONCE() static variables")
was intended to collect all .data.unlikely sections into one chunk.
However, this has not worked when CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
or CONFIG_LTO_CLANG is enabled, because .data.unlikely matches the
.data.[0-9a-zA-Z_]* pattern in the DATA_MAIN macro.

Commit cb87481ee89d ("kbuild: linker script do not match C names unless
LD_DEAD_CODE_DATA_ELIMINATION is configured") was introduced to suppress
the issue for the default CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=n case,
providing a minimal fix for stable backporting. We were aware this did
not address the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y. The
plan was to apply correct fixes and then revert cb87481ee89d. [1]

Seven years have passed since then, yet the #ifdef workaround remains in
place.

Using a ".." separator in the section name fixes the issue for
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION and CONFIG_LTO_CLANG.

[1]: https://lore.kernel.org/linux-kbuild/CAK7LNASck6BfdLnESxXUeECYL26yUDm0cwRZuM4gmaWUkxjL5g@mail.gmail.com/

Fixes: cb87481ee89d ("kbuild: linker script do not match C names unless LD_DEAD_CODE_DATA_ELIMINATION is configured")
Signed-off-by: Masahiro Yamada <[email protected]>

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rcu/tasks: Add detailed grace-period and barrier diagnostics

This commit adds rcu_tasks_torture_stats_print(),
rcu_tasks_trace_torture_stats_print(), and
rcu_tasks_rude_torture_stats_print() functio

rcu/tasks: Add detailed grace-period and barrier diagnostics

This commit adds rcu_tasks_torture_stats_print(),
rcu_tasks_trace_torture_stats_print(), and
rcu_tasks_rude_torture_stats_print() functions that provide detailed
diagnostics on grace-period, callback, and barrier state.

Signed-off-by: "Paul E. McKenney" <[email protected]>
Signed-off-by: Neeraj Upadhyay <[email protected]>

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rcu-tasks: Remove RCU Tasks Rude asynchronous APIs

The call_rcu_tasks_rude() and rcu_barrier_tasks_rude() APIs are currently
unused. This commit therefore removes their definitions and boot-time
se

rcu-tasks: Remove RCU Tasks Rude asynchronous APIs

The call_rcu_tasks_rude() and rcu_barrier_tasks_rude() APIs are currently
unused. This commit therefore removes their definitions and boot-time
self-tests.

Signed-off-by: Paul E. McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Signed-off-by: Neeraj Upadhyay <[email protected]>

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srcu: faster gp seq wrap-around

Using a higher value for the initial gp sequence counters allows for
wrapping to occur faster. It can help with surfacing any issues that may
be happening as a result

srcu: faster gp seq wrap-around

Using a higher value for the initial gp sequence counters allows for
wrapping to occur faster. It can help with surfacing any issues that may
be happening as a result of the wrap around.

Signed-off-by: JP Kobryn <[email protected]>
Tested-by: Paul E. McKenney <[email protected]>
Signed-off-by: Neeraj Upadhyay <[email protected]>

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rcu/nocb: Introduce RCU_NOCB_LOCKDEP_WARN()

Checking for races against concurrent (de-)offloading implies the
creation of !CONFIG_RCU_NOCB_CPU stubs to check if each relevant lock
is held. For now t

rcu/nocb: Introduce RCU_NOCB_LOCKDEP_WARN()

Checking for races against concurrent (de-)offloading implies the
creation of !CONFIG_RCU_NOCB_CPU stubs to check if each relevant lock
is held. For now this only implies the nocb_lock but more are to be
expected.

Create instead a NOCB specific version of RCU_LOCKDEP_WARN() to avoid
the proliferation of stubs.

Signed-off-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Signed-off-by: Neeraj Upadhyay <[email protected]>

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cpumask: cleanup core headers inclusion

Many core headers include cpumask.h for nothing. Drop it.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Yury No

cpumask: cleanup core headers inclusion

Many core headers include cpumask.h for nothing. Drop it.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Yury Norov <[email protected]>
Cc: Amit Daniel Kachhap <[email protected]>
Cc: Anna-Maria Behnsen <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Daniel Lezcano <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ulf Hansson <[email protected]>
Cc: Vincent Guittot <[email protected]>
Cc: Viresh Kumar <[email protected]>
Cc: Yury Norov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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Revert "rcu-tasks: Fix synchronize_rcu_tasks() VS zap_pid_ns_processes()"

This reverts commit 28319d6dc5e2ffefa452c2377dd0f71621b5bff0. The race
it fixed was subject to conditions that don't exist a

Revert "rcu-tasks: Fix synchronize_rcu_tasks() VS zap_pid_ns_processes()"

This reverts commit 28319d6dc5e2ffefa452c2377dd0f71621b5bff0. The race
it fixed was subject to conditions that don't exist anymore since:

1612160b9127 ("rcu-tasks: Eliminate deadlocks involving do_exit() and RCU tasks")

This latter commit removes the use of SRCU that used to cover the
RCU-tasks blind spot on exit between the tasklist's removal and the
final preemption disabling. The task is now placed instead into a
temporary list inside which voluntary sleeps are accounted as RCU-tasks
quiescent states. This would disarm the deadlock initially reported
against PID namespace exit.

Signed-off-by: Frederic Weisbecker <[email protected]>
Reviewed-by: Oleg Nesterov <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>

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rcu: Add lockdep_assert_in_rcu_read_lock() and friends

There is no direct RCU counterpart to lockdep_assert_irqs_disabled()
and friends. Although it is possible to construct them, it would
be more

rcu: Add lockdep_assert_in_rcu_read_lock() and friends

There is no direct RCU counterpart to lockdep_assert_irqs_disabled()
and friends. Although it is possible to construct them, it would
be more convenient to have the following lockdep assertions:

lockdep_assert_in_rcu_read_lock()
lockdep_assert_in_rcu_read_lock_bh()
lockdep_assert_in_rcu_read_lock_sched()
lockdep_assert_in_rcu_reader()

This commit therefore creates them.

Reported-by: Jens Axboe <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>

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rcu: Mollify sparse with RCU guard

When using "guard(rcu)();" sparse will complain, because even
though it now understands the cleanup attribute, it doesn't
evaluate the calls from it at function ex

rcu: Mollify sparse with RCU guard

When using "guard(rcu)();" sparse will complain, because even
though it now understands the cleanup attribute, it doesn't
evaluate the calls from it at function exit, and thus doesn't
count the context correctly.

Given that there's a conditional in the resulting code:

static inline void class_rcu_destructor(class_rcu_t *_T)
{
if (_T->lock) {
rcu_read_unlock();
}
}

it seems that even trying to teach sparse to evalulate the
cleanup attribute function it'd still be difficult to really
make it understand the full context here.

Suppress the sparse warning by just releasing the context in
the acquisition part of the function, after all we know it's
safe with the guard, that's the whole point of it.

Signed-off-by: Johannes Berg <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>

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rcu: Remove redundant CONFIG_PROVE_RCU #if condition

The #if condition controlling the rcu_preempt_sleep_check() definition
has a redundant check for CONFIG_PREEMPT_RCU, which is already checked
for

rcu: Remove redundant CONFIG_PROVE_RCU #if condition

The #if condition controlling the rcu_preempt_sleep_check() definition
has a redundant check for CONFIG_PREEMPT_RCU, which is already checked
for by an enclosing #ifndef. This commit therefore removes this redundant
condition from the inner #if.

Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>

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rcu: Update lockdep while in RCU read-side critical section

With Ankur's lazy-/auto-preemption patches applied and with a
lazy-preemptible kernel in combination with a non-preemptible RCU,
lockdep s

rcu: Update lockdep while in RCU read-side critical section

With Ankur's lazy-/auto-preemption patches applied and with a
lazy-preemptible kernel in combination with a non-preemptible RCU,
lockdep sometimes complains about context switches within RCU read-side
critical sections. This is a false positive due to rcu_read_unlock()
updating lockdep state too late:

__release(RCU);
__rcu_read_unlock();
// Context switch here results in lockdep false positive!!!
rcu_lock_release(&rcu_lock_map); /* Keep acq info for rls diags. */

Although this complaint could also happen with preemptible RCU
in a preemptible kernel, the odds of that happening aer quite low.
In constrast, with non-preemptible RCU, a long critical section has a
high probability of performing a context switch from the preempt_enable()
in __rcu_read_unlock().

The fix is straightforward, just move the rcu_lock_release()
within rcu_read_unlock() to obtain the reverse order from that of
rcu_read_lock():

rcu_lock_release(&rcu_lock_map); /* Keep acq info for rls diags. */
__release(RCU);
__rcu_read_unlock();

This commit makes this change.

Co-developed-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
Co-developed-by: Joel Fernandes (Google) <[email protected]>
Signed-off-by: Joel Fernandes (Google) <[email protected]>
Co-developed-by: Boqun Feng <[email protected]>
Signed-off-by: Boqun Feng <[email protected]>
Signed-off-by: Uladzislau Rezki (Sony) <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Cc: Ankur Arora <[email protected]>
Cc: Thomas Gleixner <[email protected]>

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rcu: add a helper to report consolidated flavor QS

When under heavy load, network processing can run CPU-bound for many
tens of seconds. Even in preemptible kernels (non-RT kernel), this can
block R

rcu: add a helper to report consolidated flavor QS

When under heavy load, network processing can run CPU-bound for many
tens of seconds. Even in preemptible kernels (non-RT kernel), this can
block RCU Tasks grace periods, which can cause trace-event removal to
take more than a minute, which is unacceptably long.

This commit therefore creates a new helper function that passes through
both RCU and RCU-Tasks quiescent states every 100 milliseconds. This
hard-coded value suffices for current workloads.

Suggested-by: Paul E. McKenney <[email protected]>
Reviewed-by: Jesper Dangaard Brouer <[email protected]>
Signed-off-by: Yan Zhai <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Acked-by: Jesper Dangaard Brouer <[email protected]>
Link: https://lore.kernel.org/r/90431d46ee112d2b0af04dbfe936faaca11810a5.1710877680.git.yan@cloudflare.com
Signed-off-by: Jakub Kicinski <[email protected]>

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rcu-tasks: Repair RCU Tasks Trace quiescence check

The context-switch-time check for RCU Tasks Trace quiescence expects
current->trc_reader_special.b.need_qs to be zero, and if so, updates
it to TRC

rcu-tasks: Repair RCU Tasks Trace quiescence check

The context-switch-time check for RCU Tasks Trace quiescence expects
current->trc_reader_special.b.need_qs to be zero, and if so, updates
it to TRC_NEED_QS_CHECKED. This is backwards, because if this value
is zero, there is no RCU Tasks Trace grace period in flight, an thus
no need for a quiescent state. Instead, when a grace period starts,
this field is set to TRC_NEED_QS.

This commit therefore changes the check from zero to TRC_NEED_QS.

Reported-by: Steven Rostedt <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Tested-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Boqun Feng <[email protected]>

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srcu: Use try-lock lockdep annotation for NMI-safe access.

It is claimed that srcu_read_lock_nmisafe() NMI-safe. However it
triggers a lockdep if used from NMI because lockdep expects a deadlock
sin

srcu: Use try-lock lockdep annotation for NMI-safe access.

It is claimed that srcu_read_lock_nmisafe() NMI-safe. However it
triggers a lockdep if used from NMI because lockdep expects a deadlock
since nothing disables NMIs while the lock is acquired.

This is because commit f0f44752f5f61 ("rcu: Annotate SRCU's update-side
lockdep dependencies") annotates synchronize_srcu() as a write lock
usage. This helps to detect a deadlocks such as
srcu_read_lock();
synchronize_srcu();
srcu_read_unlock();

The side effect is that the lock srcu_struct now has a USED usage in normal
contexts, so it conflicts with a USED_READ usage in NMI. But this shouldn't
cause a real deadlock because the write lock usage from synchronize_srcu()
is a fake one and only used for read/write deadlock detection.

Use a try-lock annotation for srcu_read_lock_nmisafe() to avoid lockdep
complains if used from NMI.

Fixes: f0f44752f5f6 ("rcu: Annotate SRCU's update-side lockdep dependencies")
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Boqun Feng <[email protected]>
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Neeraj Upadhyay (AMD) <[email protected]>

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rcu: Remove unused macros from rcupdate.h

ulong2long, USHORT_CMP_GE and USHORT_CMP_LT are redundant and have been
unused for quite a few releases.

Signed-off-by: Pedro Falcato <pedro.falcato@gmail.

rcu: Remove unused macros from rcupdate.h

ulong2long, USHORT_CMP_GE and USHORT_CMP_LT are redundant and have been
unused for quite a few releases.

Signed-off-by: Pedro Falcato <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Signed-off-by: Neeraj Upadhyay (AMD) <[email protected]>

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rcu: Standardize explicit CPU-hotplug calls

rcu_report_dead() and rcutree_migrate_callbacks() have their headers in
rcupdate.h while those are pure rcutree calls, like the other CPU-hotplug
function

rcu: Standardize explicit CPU-hotplug calls

rcu_report_dead() and rcutree_migrate_callbacks() have their headers in
rcupdate.h while those are pure rcutree calls, like the other CPU-hotplug
functions.

Also rcu_cpu_starting() and rcu_report_dead() have different naming
conventions while they mirror each other's effects.

Fix the headers and propose a naming that relates both functions and
aligns with the prefix of other rcutree CPU-hotplug functions.

Reviewed-by: Paul E. McKenney <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>

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rcu: Assume rcu_report_dead() is always called locally

rcu_report_dead() has to be called locally by the CPU that is going to
exit the RCU state machine. Passing a cpu argument here is error-prone
a

rcu: Assume rcu_report_dead() is always called locally

rcu_report_dead() has to be called locally by the CPU that is going to
exit the RCU state machine. Passing a cpu argument here is error-prone
and leaves the possibility for a racy remote call.

Use local access instead.

Reviewed-by: Paul E. McKenney <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>

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