This commit prepares for the removal of SRCU-Lite by removing the SRCU-L
rcutorture scenario that tests it.
Both SRCU-lite and SRCU-fast provide faster readers by dropping the
smp_mb() call from their lock and unlock primitives, but incur a pair
of added RCU grace periods during the SRCU grace period. There is a
trivial mapping from the SRCU-lite API to that of SRCU-fast, so there
should be no transition issues.
[ paulmck: Apply Christoph Hellwig feedback. ]
Signed-off-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>
Because the BUSTED scenario intentionally executes too-short
readers, this commit enables the RCU_TORTURE_TEST_CHK_RDR_STATE,
RCU_TORTURE_TEST_LOG_CPU, and RCU_TORTURE_TEST_LOG_GP Kconfig options
to test the resulting reader-segment dump.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>
Back in the day, rcutorture was about the only thing that tested off-stack
CPU masks, but now any arm64 system with more than 256 CPUs tests it
full time. In fact, it is necessary to hack the kernel to prevent such
a system from testing off-stack CPU masks. This means that there is
no longer much point in rcutorture going out of its way to test this.
And given the differences in how CPUMASK_OFFSTACK is enabled in x86 and
arm64, rcutorture would need to go out of its way.
This commit therefore removes CONFIG_CPUMASK_OFFSTACK=y (and the
CONFIG_MAXSMP=y required to enable it on x86) from TREE01.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
The TREE01.boot nr_cpus kernel boot parameter has been set to 43 for
more than seven years, but it can cause RCU CPU stall warnings on arm64,
most of the time involving the stop-machine subsystem. This should
not be too surprising, given that this causes 43 vCPUs to spin with
interrupts disabled when there are only eight physical CPUs.
The point of this CPU overcommit is to test the ability of expedited RCU
grace period initialization to handle races with incoming CPUs that have
never previously been online. But limiting to 17 CPUs instead of 43
allows time for this code to be exercised, and eliminates (or at least
greatly reduces) the incidence of RCU CPU stall warnings on arm64.
So this commit therefore sets nr_cpus=17 in TREE01.boot.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
This commit tests lazy preemption by causing the TREE07 rcutorture
scenario to build its kernel with CONFIG_PREEMPT_LAZY=y.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
This commit tests lazy preemption by causing the TREE10 rcutorture
scenario to build its kernel with CONFIG_PREEMPT_LAZY=y.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Add extra parameters for rcutorture module. One is the "nfakewriters"
which is set -1. There will be created number of test-kthreads which
correspond to number of CPUs in a test system. Those threads randomly
invoke synchronize_rcu() call.
Apart of that "rcu_normal" is set to 1, because it is specifically for
a normal synchronize_rcu() testing, also a newly added parameter which
is "rcu_normal_wake_from_gp" is set to 1 also. That prevents interaction
with other callbacks in a system.
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Link: https://lore.kernel.org/r/20250227131613.52683-2-urezki@gmail.com
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
This commit causes the rcutorture SRCU-P scenario use the
srcu_read_lock_fast() and srcu_read_unlock_fast() functions. This will
cause these two functions to be regularly tested by several developers
(myself included), for example, those who use torture.sh as an RCU
acceptance test.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
This commit adds the rcutorture.preempt_duration module parameter to
rcutorture's TREE03.boot parameter list in order to better test preemption
of RCU read-side critical sections.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
This commit adds an rcutorture scenario that tests light-weight SRCU
readers. While in the area, it adjusts the size of the TREE10 scenario.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: <bpf@vger.kernel.org>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
This commit adds a TINY scenario in order to support tests of Tiny RCU
and Tiny SRCU.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
This commit adds the rcutree.nohz_full_patience_delay=1000 kernel boot
parameter to the TREE07 scenario, on the observation that "if it ain't
tested, it don't work".
Signed-off-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Add CFcommon.arch for arch-specific Kconfig options.
In accordance with [1], [2] and [3], move the x86-specific kernel option
CONFIG_HYPERVISOR_GUEST to CFcommon.i686 and CFcommon.x86_64, and also
move the x86/PowerPC CONFIG_KVM_GUEST Kconfig option to CFcommon.i686,
CFcommon.x86_64, and CFcommon.ppc64le.
The "arch" in CFcommon.arch is taken from the "uname -m" command.
[1] https://lore.kernel.org/all/20240427005626.1365935-1-zhouzhouyi@gmail.com/
[2] https://lore.kernel.org/all/059d36ce-6453-42be-a31e-895abd35d590@paulmck-laptop/
[3] https://lore.kernel.org/all/ZnBkHosMDhsh4H8g@J2N7QTR9R3/
Tested in x86_64 and PPC VM of Open Source Lab of Oregon State University.
Fixes: a6fda6dab9 ("rcutorture: Tweak kvm options")
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
The TREE09 rcutorture scenario exhausts memory from time to time, and
this is due to a reader being preempted and blocking grace periods,
thus preventing recycling of the memory used in callback-flooding tests.
This commit therefore enables RCU priority boosting and sets the boosting
delay to 100 milliseconds after grace-period start.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
There is code in rcu_implicit_dynticks_qs() that checks for the current
grace period being halfway to the RCU CPU stall timeout, but rcutorture
currently does not test this code. This commit therefore adds a 14-second
stall to the TREE07 scenario in order to test this code given the default
RCU CPU stall warning timeout of 21 seconds.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>
This commit adds CONFIG_DEBUG_OBJECTS=y to the TRACE02 rcutorture scenario
to catch any further RCU Tasks bugs involving this Kconfig option.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
This pull request prevents some memory-exhaustion false-postitive failures
in scftorture testing.
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Merge tag 'scftorture.2023.08.15a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull smp_call_function torture-test updates from Paul McKenney:
"This prevents some memory-exhaustion false-postitive failures in
scftorture testing"
* tag 'scftorture.2023.08.15a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
scftorture: Add CONFIG_PREEMPT_DYNAMIC=n to NOPREEMPT scenario
scftorture: Pause testing after memory-allocation failure
scftorture: Forgive memory-allocation failure if KASAN
torture: Scale scftorture memory based on number of CPUs
Currently, the kernel boot parameters specified by the kvm.sh --bootargs
parameter are placed near the beginning of the -append list that is
passed to qemu. This means that in the not-uncommon case of a kernel
boot parameter where the last argument wins, the --bootargs list overrides
neither the list in the .boot file nor the additional parameters supplied
by the rcutorture scripting.
This commit therefore places the kernel boot parameters specified by
the kvm.sh --bootargs parameter at the end of qemu's -append list.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The TASKS03 scenario specifies both CONFIG_RCU_EXPERT=y and
removes #CHECK#CONFIG_RCU_EXPERT=n in order to be consistent with
CONFIG_RCU_EXPERT=y prerequisites.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that the BOOTPARAM_HOTPLUG_CPU0 Kconfig option is in the process of
being removed, it is time to remove rcutorture's use of it.
Link: https://lore.kernel.org/lkml/20230414232309.510911744@linutronix.de/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <x86@kernel.org>
It is no longer possible to build a kernel with a preemption-disabled
RCU without use of CONFIG_PREEMPT_DYNAMIC=n. This commit therefore
adds CONFIG_PREEMPT_DYNAMIC=n to the scf torture type's NOPREEMPT
scenario file.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
It is no longer possible to build a kernel with a preemption-disabled
RCU without use of CONFIG_PREEMPT_DYNAMIC=n. This commit therefore
adds CONFIG_PREEMPT_DYNAMIC=n to the rcuscale torture type's TRACE01
scenario file.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
It is no longer possible to build a kernel with a preemption-disabled
RCU without use of CONFIG_PREEMPT_DYNAMIC=n. This commit therefore
adds CONFIG_PREEMPT_DYNAMIC=n to the refscale torture type's NOPREEMPT
scenario file.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The BUSTED-BOOST and TREE03 scenarios specify a mythical tree.use_softirq
module parameter, which means a failure to get full test coverage. This
commit therefore corrects the name to rcutree.use_softirq.
Fixes: e2b949d543 ("rcutorture: Make TREE03 use real-time tree.use_softirq setting")
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
o MAINTAINERS files additions and changes.
o Fix hotplug warning in nohz code.
o Tick dependency changes by Zqiang.
o Lazy-RCU shrinker fixes by Zqiang.
o rcu-tasks stall reporting improvements by Neeraj.
o Initial changes for renaming of k[v]free_rcu() to its new k[v]free_rcu_mightsleep()
name for robustness.
o Documentation Updates:
o Significant changes to srcu_struct size.
o Deadlock detection for srcu_read_lock() vs synchronize_srcu() from Boqun.
o rcutorture and rcu-related tool, which are targeted for v6.4 from Boqun's tree.
o Other misc changes.
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Merge tag 'rcu.6.4.april5.2023.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux
Pull RCU updates from Joel Fernandes:
- Updates and additions to MAINTAINERS files, with Boqun being added to
the RCU entry and Zqiang being added as an RCU reviewer.
I have also transitioned from reviewer to maintainer; however, Paul
will be taking over sending RCU pull-requests for the next merge
window.
- Resolution of hotplug warning in nohz code, achieved by fixing
cpu_is_hotpluggable() through interaction with the nohz subsystem.
Tick dependency modifications by Zqiang, focusing on fixing usage of
the TICK_DEP_BIT_RCU_EXP bitmask.
- Avoid needless calls to the rcu-lazy shrinker for CONFIG_RCU_LAZY=n
kernels, fixed by Zqiang.
- Improvements to rcu-tasks stall reporting by Neeraj.
- Initial renaming of k[v]free_rcu() to k[v]free_rcu_mightsleep() for
increased robustness, affecting several components like mac802154,
drbd, vmw_vmci, tracing, and more.
A report by Eric Dumazet showed that the API could be unknowingly
used in an atomic context, so we'd rather make sure they know what
they're asking for by being explicit:
https://lore.kernel.org/all/20221202052847.2623997-1-edumazet@google.com/
- Documentation updates, including corrections to spelling,
clarifications in comments, and improvements to the srcu_size_state
comments.
- Better srcu_struct cache locality for readers, by adjusting the size
of srcu_struct in support of SRCU usage by Christoph Hellwig.
- Teach lockdep to detect deadlocks between srcu_read_lock() vs
synchronize_srcu() contributed by Boqun.
Previously lockdep could not detect such deadlocks, now it can.
- Integration of rcutorture and rcu-related tools, targeted for v6.4
from Boqun's tree, featuring new SRCU deadlock scenarios, test_nmis
module parameter, and more
- Miscellaneous changes, various code cleanups and comment improvements
* tag 'rcu.6.4.april5.2023.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux: (71 commits)
checkpatch: Error out if deprecated RCU API used
mac802154: Rename kfree_rcu() to kvfree_rcu_mightsleep()
rcuscale: Rename kfree_rcu() to kfree_rcu_mightsleep()
ext4/super: Rename kfree_rcu() to kfree_rcu_mightsleep()
net/mlx5: Rename kfree_rcu() to kfree_rcu_mightsleep()
net/sysctl: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
lib/test_vmalloc.c: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
tracing: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
misc: vmw_vmci: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
drbd: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
rcu: Protect rcu_print_task_exp_stall() ->exp_tasks access
rcu: Avoid stack overflow due to __rcu_irq_enter_check_tick() being kprobe-ed
rcu-tasks: Report stalls during synchronize_srcu() in rcu_tasks_postscan()
rcu: Permit start_poll_synchronize_rcu_expedited() to be invoked early
rcu: Remove never-set needwake assignment from rcu_report_qs_rdp()
rcu: Register rcu-lazy shrinker only for CONFIG_RCU_LAZY=y kernels
rcu: Fix missing TICK_DEP_MASK_RCU_EXP dependency check
rcu: Fix set/clear TICK_DEP_BIT_RCU_EXP bitmask race
rcu/trace: use strscpy() to instead of strncpy()
tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem
...
This commit enables the RCU_LAZY Kconfig option in scenario TREE04 in
order to provide some ongoing testing of this configuration.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
There is now a BOOTPARAM_HOTPLUG_CPU0 Kconfig option that allows CPU 0
to be offlined on x86 systems. This commit therefore sets this option in
the TREE01 rcutorture scenario in order to regularly test this capability.
Reported-by: "Zhang, Qiang1" <qiang1.zhang@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
There is an extraneous "scf" in the per_version_boot_params shell function
used by scftorture. No harm done in that it is just passed as an argument
to the /init program in initrd, but this commit nevertheless removes it.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that CONFIG_PREEMPT_DYNAMIC=y is the default, kernels that are
ostensibly built with CONFIG_PREEMPT_NONE=y or CONFIG_PREEMPT_VOLUNTARY=y
are now actually built with CONFIG_PREEMPT=y, but are by default booted
so as to disable preemption. Although this allows much more flexibility
from a single kernel binary, it means that the current rcutorture
scenarios won't find build errors that happen only when preemption is
fully disabled at build time.
This commit therefore adds CONFIG_PREEMPT_DYNAMIC=n to several scenarios,
and while in the area switches one from CONFIG_PREEMPT_NONE=y to
CONFIG_PREEMPT_VOLUNTARY=y to add coverage of this Kconfig option.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adjusts the scftorture PREEMPT and NOPREEMPT scenarios to
account for the TASKS_RCU Kconfig option being explicitly selected rather
than computed in isolation.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, a CONFIG_PREEMPT_NONE=y kernel substitutes normal RCU for
RCU Tasks Rude and RCU Tasks Trace. Unless that kernel builds rcuscale,
whether built-in or as a module, in which case these RCU Tasks flavors are
(unnecessarily) built in. This both increases kernel size and increases
the complexity of certain tracing operations. This commit therefore
decouples the presence of rcuscale from the presence of RCU Tasks Rude
and RCU Tasks Trace.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, a CONFIG_PREEMPT_NONE=y kernel substitutes normal RCU for
RCU Tasks. Unless that kernel builds rcuscale, whether built-in or as
a module, in which case RCU Tasks is (unnecessarily) built. This both
increases kernel size and increases the complexity of certain tracing
operations. This commit therefore decouples the presence of rcuscale
from the presence of RCU Tasks.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, a CONFIG_PREEMPT_NONE=y kernel substitutes normal RCU for
RCU Tasks Rude and RCU Tasks Trace. Unless that kernel builds refscale,
whether built-in or as a module, in which case these RCU Tasks flavors are
(unnecessarily) built in. This both increases kernel size and increases
the complexity of certain tracing operations. This commit therefore
decouples the presence of refscale from the presence of RCU Tasks Rude
and RCU Tasks Trace.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, a CONFIG_PREEMPT_NONE=y kernel substitutes normal RCU for
RCU Tasks. Unless that kernel builds refscale, whether built-in or as a
module, in which case RCU Tasks is (unnecessarily) built in. This both
increases kernel size and increases the complexity of certain tracing
operations. This commit therefore decouples the presence of refscale
from the presence of RCU Tasks.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcutorture test suite makes double use of the rcutorture.stat_interval
module parameter. As its name suggests, it controls the frequency
of statistics printing, but it also controls the rcu_torture_writer()
stall timeout. The current setting of 15 seconds works surprisingly well.
However, given that the RCU tasks stall-warning timeout is ten -minutes-,
15 seconds is too short for TASKS02, which runs a non-preemptible kernel
on a single CPU.
This commit therefore adds checks for per-scenario specification of the
rcutorture.stat_interval module parameter.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that CONFIG_PREEMPT_DYNAMIC=y is the default, TASKS02 no longer
builds a pure non-preemptible kernel that uses Tiny RCU. This commit
therefore fixes this new hole in rcutorture testing by adding
CONFIG_PREEMPT_DYNAMIC=n to the TASKS02 rcutorture scenario.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Unless a kernel builds rcutorture, whether built-in or as a module, that
kernel is also built with CONFIG_TASKS_RUDE_RCU, whether anything else
needs Tasks Rude RCU or not. This unnecessarily increases kernel size.
This commit therefore decouples the presence of rcutorture from the
presence of RCU Tasks Rude.
However, there is a need to select CONFIG_TASKS_RUDE_RCU for testing
purposes. Except that casual users must not be bothered with
questions -- for them, this needs to be fully automated. There is
thus a CONFIG_FORCE_TASKS_RUDE_RCU that selects CONFIG_TASKS_RUDE_RCU,
is user-selectable, but which depends on CONFIG_RCU_EXPERT.
[ paulmck: Apply kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, a CONFIG_PREEMPT_NONE=y kernel substitutes normal RCU for
RCU Tasks. Unless that kernel builds rcutorture, whether built-in or as
a module, in which case RCU Tasks is (unnecessarily) used. This both
increases kernel size and increases the complexity of certain tracing
operations. This commit therefore decouples the presence of rcutorture
from the presence of RCU Tasks.
However, there is a need to select CONFIG_TASKS_RCU for testing purposes.
Except that casual users must not be bothered with questions -- for them,
this needs to be fully automated. There is thus a CONFIG_FORCE_TASKS_RCU
that selects CONFIG_TASKS_RCU, is user-selectable, but which depends
on CONFIG_RCU_EXPERT.
[ paulmck: Apply kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Unless a kernel builds rcutorture, whether built-in or as a module, that
kernel is also built with CONFIG_TASKS_TRACE_RCU, whether anything else
needs Tasks Trace RCU or not. This unnecessarily increases kernel size.
This commit therefore decouples the presence of rcutorture from the
presence of RCU Tasks Trace.
However, there is a need to select CONFIG_TASKS_TRACE_RCU for
testing purposes. Except that casual users must not be bothered with
questions -- for them, this needs to be fully automated. There is thus
a CONFIG_FORCE_TASKS_TRACE_RCU that selects CONFIG_TASKS_TRACE_RCU,
is user-selectable, but which depends on CONFIG_RCU_EXPERT.
[ paulmck: Apply kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, any kernel built with CONFIG_PREEMPTION=y also gets
CONFIG_TASKS_RCU=y, which is not helpful to people trying to build
preemptible kernels of minimal size.
Because CONFIG_TASKS_RCU=y is needed only in kernels doing tracing of
one form or another, this commit moves from TASKS_RCU deciding when it
should be enabled to the tracing Kconfig options explicitly selecting it.
This allows building preemptible kernels without TASKS_RCU, if desired.
This commit also updates the SRCU-N and TREE09 rcutorture scenarios
in order to avoid Kconfig errors that would otherwise result from
CONFIG_TASKS_RCU being selected without its CONFIG_RCU_EXPERT dependency
being met.
[ paulmck: Apply BPF_SYSCALL feedback from Andrii Nakryiko. ]
Reported-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adjusts RUDE01 to 3 CPUs and TRACE01 to 5 CPUs in order to
test Tasks RCU's ability to handle non-power-of-two numbers of CPUs.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Thie commit adds kernel boot parameters to the SRCU-N and SRCU-P
rcutorture scenarios to cause SRCU-N to test contention-based resizing
and SRCU-P to test init_srcu_struct()-time resizing. Note that this
also tests never-resizing because the contention-based resizing normally
takes some minutes to make the shift.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
