[PATCH RFC v2 18/24] doc: Add hazptrtorture module parameters

Add the hazard-pointer-torture module parameters to kernel-parameters.txt.

Signed-off-by: Paul E. McKenney <[email protected]>
---
 .../admin-guide/kernel-parameters.txt         | 96 +++++++++++++++++++
 1 file changed, 96 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b5493a7f8f2281..7977ce806a2647 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1951,6 +1951,102 @@ Kernel parameters
 			for 64-bit NUMA, off otherwise.
 			Format: 0 | 1 (for off | on)
 
+	hazptrtorture.defer_modulus= [KNL]
+			Defer release of the hazard pointer on average
+			one out of the specified number of times.  Zero
+			disables.  Negative one defaults to 1,000 times
+			nr_cpu_ids, unless hazptr.kthread_do_pending_ms is
+			equal to zero, in which case it instead defaults
+			to zero (disabled).
+
+	hazptrtorture.irq_acquire= [KNL]
+			Acquire hazard pointers from an irq handler on average
+			one out of the specified number of times.  Zero
+			disables.  Negative one defaults to 1,000 times
+			nr_cpu_ids.
+
+	hazptrtorture.irq_release= [KNL]
+			Release hazard pointers from an irq handler on average
+			one out of the specified number of times.  Zero
+			disables.  Negative one defaults to 1,000 times
+			nr_cpu_ids.
+
+	hazptrtorture.kthread_do_pending_ms= [KNL]
+			Interval between cleanup of pending (deferred)
+			hazard-pointer releases in milliseconds.
+			Zero disables.	Negative one defaults to three
+			milliseconds, unless hazptr.kthread_do_pending_ms
+			is equal to zero, in which case it instead
+			defaults to zero (disabled).
+
+	hazptrtorture.nreaders= [KNL]
+			Number of hazard-pointer reader kthreads, each
+			of which repeatedly acquires and releases hazard
+			pointers.  If the value is zero, one reader
+			is spawned.  If the value is less than zero,
+			the absolute value is multiplied by the number
+			of online CPUs at initialization time.
+
+	hazptrtorture.nwriters= [KNL]
+			Controls whether or not there is a writer.
+			There is at most one writer, so this value must
+			be zero or one.
+
+	hazptrtorture.onoff_holdoff= [KNL]
+			Set time (s) after boot for CPU-hotplug testing.
+
+	hazptrtorture.onoff_interval= [KNL]
+			Set time (jiffies) between CPU-hotplug operations,
+			or zero to disable CPU-hotplug testing.
+
+	hazptrtorture.preempt_duration= [KNL]
+			Set duration (in milliseconds) of preemptions
+			by a high-priority FIFO real-time task.  Set to
+			zero (the default) to disable.	The CPUs to
+			preempt are selected randomly from the set that
+			are online at a given point in time.  Races with
+			CPUs going offline are ignored, with that attempt
+			at preemption skipped.
+
+	hazptrtorture.preempt_interval= [KNL]
+			Set interval (in milliseconds, defaulting to one
+			second) between preemptions by a high-priority
+			FIFO real-time task.  This delay is mediated
+			by an hrtimer and is further fuzzed to avoid
+			inadvertent synchronizations.
+
+	hazptrtorture.reader_sleep_us= [KNL]
+			Set occassional read-side sleep time in
+			microseconds, defaulting to zero for disabled.
+
+	hazptrtorture.shuffle_interval= [KNL]
+			Set task-shuffle interval (seconds).  Shuffling
+			tasks allows some CPUs to go into dyntick-idle
+			mode during the hazptrtorture test.
+
+	hazptrtorture.shutdown_secs= [KNL]
+			Set time (s) after boot system shutdown.  This
+			is useful for hands-off automated testing.
+
+	hazptrtorture.stat_interval= [KNL]
+			Time (s) between statistics printk()s.
+
+	hazptrtorture.stutter= [KNL]
+			Time (s) to stutter testing, for example,
+			specifying three seconds (the default) causes
+			the test to run for three seconds, wait
+			for five seconds, and so on.  This tests the
+			hazard-pointers primitives' ability to transition
+			abruptly to and from idle.  Setting this to zero
+			disables stuttering.
+
+	hazptrtorture.torture_type= [KNL]
+			Specify the hazard-pointers implementation
+			to test.
+
+	hazptrtorture.verbose= [KNL]
+			Enable additional printk() statements.
+
 	hd=		[EIDE] (E)IDE hard drive subsystem geometry
 			Format: <cyl>,<head>,<sect>
 
-- 
2.40.1