Merge branches 'doc.2019.01.26a', 'fixes.2019.01.26a', 'sil.2019.01.26a',... (e7ffb4eb) · Commits · 戴 / test

Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html

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		@@ -485,13 +485,13 @@ section that the grace period must wait on.
		noted by <tt>rcu_node_context_switch()</tt> on the left.
		On the other hand, if the CPU takes a scheduler-clock interrupt
		while executing in usermode, a quiescent state will be noted by
		<tt>rcu_check_callbacks()</tt> on the right.
		<tt>rcu_sched_clock_irq()</tt> on the right.
		Either way, the passage through a quiescent state will be noted
		in a per-CPU variable.

		<p>The next time an <tt>RCU_SOFTIRQ</tt> handler executes on
		this CPU (for example, after the next scheduler-clock
		interrupt), <tt>__rcu_process_callbacks()</tt> will invoke
		interrupt), <tt>rcu_core()</tt> will invoke
		<tt>rcu_check_quiescent_state()</tt>, which will notice the
		recorded quiescent state, and invoke
		<tt>rcu_report_qs_rdp()</tt>.
		@@ -651,7 +651,7 @@ to end.
		These callbacks are identified by <tt>rcu_advance_cbs()</tt>,
		which is usually invoked by <tt>__note_gp_changes()</tt>.
		As shown in the diagram below, this invocation can be triggered by
		the scheduling-clock interrupt (<tt>rcu_check_callbacks()</tt> on
		the scheduling-clock interrupt (<tt>rcu_sched_clock_irq()</tt> on
		the left) or by idle entry (<tt>rcu_cleanup_after_idle()</tt> on
		the right, but only for kernels build with
		<tt>CONFIG_RCU_FAST_NO_HZ=y</tt>).

Documentation/RCU/Design/Memory-Ordering/TreeRCU-callback-invocation.svg

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		font-weight="bold"
		font-size="192"
		id="text202-7-5"
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rcu_check_callbacks()</text>
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rcu_sched_clock_irq()</text>
		<rect
		x="7069.6187"
		y="5087.4678"

Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp.svg

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		font-style="normal"
		y="-4418.6582"
		x="3745.7725"
		xml:space="preserve">rcu_check_callbacks()</text>
		xml:space="preserve">rcu_sched_clock_irq()</text>
		</g>
		<g
		transform="translate(-850.30204,55463.106)"
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		font-style="normal"
		y="-4418.6582"
		x="3745.7725"
		xml:space="preserve">rcu_process_callbacks()</text>
		xml:space="preserve">rcu_core()</text>
		<text
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"
		id="text202-7-5-3-27-0"
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		font-style="normal"
		y="-4165.7954"
		x="3745.7725"
		xml:space="preserve">rcu_check_quiescent_state())</text>
		xml:space="preserve">rcu_check_quiescent_state()</text>
		<text
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"
		id="text202-7-5-3-27-0-9"
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		font-weight="bold"
		font-size="192"
		id="text202-7-5-19"
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rcu_check_callbacks()</text>
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rcu_sched_clock_irq()</text>
		<rect
		x="5314.2671"
		y="82817.688"

Documentation/RCU/Design/Memory-Ordering/TreeRCU-qs.svg

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		font-style="normal"
		y="-4418.6582"
		x="3745.7725"
		xml:space="preserve">rcu_check_callbacks()</text>
		xml:space="preserve">rcu_sched_clock_irq()</text>
		</g>
		<g
		transform="translate(399.7744,828.86448)"
		@@ -797,7 +797,7 @@
		font-style="normal"
		y="-4418.6582"
		x="3745.7725"
		xml:space="preserve">rcu_process_callbacks()</text>
		xml:space="preserve">rcu_core()</text>
		<text
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"
		id="text202-7-5-3-27-0"
		@@ -806,7 +806,7 @@
		font-style="normal"
		y="-4165.7954"
		x="3745.7725"
		xml:space="preserve">rcu_check_quiescent_state())</text>
		xml:space="preserve">rcu_check_quiescent_state()</text>
		<text
		style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"
		id="text202-7-5-3-27-0-9"

Documentation/RCU/torture.txt

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		@@ -10,173 +10,8 @@ status messages via printk(), which can be examined via the dmesg
		command (perhaps grepping for "torture"). The test is started
		when the module is loaded, and stops when the module is unloaded.


		MODULE PARAMETERS

		This module has the following parameters:

		fqs_duration Duration (in microseconds) of artificially induced bursts
		of force_quiescent_state() invocations. In RCU
		implementations having force_quiescent_state(), these
		bursts help force races between forcing a given grace
		period and that grace period ending on its own.

		fqs_holdoff Holdoff time (in microseconds) between consecutive calls
		to force_quiescent_state() within a burst.

		fqs_stutter Wait time (in seconds) between consecutive bursts
		of calls to force_quiescent_state().

		gp_normal Make the fake writers use normal synchronous grace-period
		primitives.

		gp_exp Make the fake writers use expedited synchronous grace-period
		primitives. If both gp_normal and gp_exp are set, or
		if neither gp_normal nor gp_exp are set, then randomly
		choose the primitive so that about 50% are normal and
		50% expedited. By default, neither are set, which
		gives best overall test coverage.

		irqreader Says to invoke RCU readers from irq level. This is currently
		done via timers. Defaults to "1" for variants of RCU that
		permit this. (Or, more accurately, variants of RCU that do
		-not- permit this know to ignore this variable.)

		n_barrier_cbs If this is nonzero, RCU barrier testing will be conducted,
		in which case n_barrier_cbs specifies the number of
		RCU callbacks (and corresponding kthreads) to use for
		this testing. The value cannot be negative. If you
		specify this to be non-zero when torture_type indicates a
		synchronous RCU implementation (one for which a member of
		the synchronize_rcu() rather than the call_rcu() family is
		used -- see the documentation for torture_type below), an
		error will be reported and no testing will be carried out.

		nfakewriters This is the number of RCU fake writer threads to run. Fake
		writer threads repeatedly use the synchronous "wait for
		current readers" function of the interface selected by
		torture_type, with a delay between calls to allow for various
		different numbers of writers running in parallel.
		nfakewriters defaults to 4, which provides enough parallelism
		to trigger special cases caused by multiple writers, such as
		the synchronize_srcu() early return optimization.

		nreaders This is the number of RCU reading threads supported.
		The default is twice the number of CPUs. Why twice?
		To properly exercise RCU implementations with preemptible
		read-side critical sections.

		onoff_interval
		The number of seconds between each attempt to execute a
		randomly selected CPU-hotplug operation. Defaults to
		zero, which disables CPU hotplugging. In HOTPLUG_CPU=n
		kernels, rcutorture will silently refuse to do any
		CPU-hotplug operations regardless of what value is
		specified for onoff_interval.

		onoff_holdoff The number of seconds to wait until starting CPU-hotplug
		operations. This would normally only be used when
		rcutorture was built into the kernel and started
		automatically at boot time, in which case it is useful
		in order to avoid confusing boot-time code with CPUs
		coming and going.

		shuffle_interval
		The number of seconds to keep the test threads affinitied
		to a particular subset of the CPUs, defaults to 3 seconds.
		Used in conjunction with test_no_idle_hz.

		shutdown_secs The number of seconds to run the test before terminating
		the test and powering off the system. The default is
		zero, which disables test termination and system shutdown.
		This capability is useful for automated testing.

		stall_cpu The number of seconds that a CPU should be stalled while
		within both an rcu_read_lock() and a preempt_disable().
		This stall happens only once per rcutorture run.
		If you need multiple stalls, use modprobe and rmmod to
		repeatedly run rcutorture. The default for stall_cpu
		is zero, which prevents rcutorture from stalling a CPU.

		Note that attempts to rmmod rcutorture while the stall
		is ongoing will hang, so be careful what value you
		choose for this module parameter! In addition, too-large
		values for stall_cpu might well induce failures and
		warnings in other parts of the kernel. You have been
		warned!

		stall_cpu_holdoff
		The number of seconds to wait after rcutorture starts
		before stalling a CPU. Defaults to 10 seconds.

		stat_interval The number of seconds between output of torture
		statistics (via printk()). Regardless of the interval,
		statistics are printed when the module is unloaded.
		Setting the interval to zero causes the statistics to
		be printed -only- when the module is unloaded, and this
		is the default.

		stutter The length of time to run the test before pausing for this
		same period of time. Defaults to "stutter=5", so as
		to run and pause for (roughly) five-second intervals.
		Specifying "stutter=0" causes the test to run continuously
		without pausing, which is the old default behavior.

		test_boost Whether or not to test the ability of RCU to do priority
		boosting. Defaults to "test_boost=1", which performs
		RCU priority-inversion testing only if the selected
		RCU implementation supports priority boosting. Specifying
		"test_boost=0" never performs RCU priority-inversion
		testing. Specifying "test_boost=2" performs RCU
		priority-inversion testing even if the selected RCU
		implementation does not support RCU priority boosting,
		which can be used to test rcutorture's ability to
		carry out RCU priority-inversion testing.

		test_boost_interval
		The number of seconds in an RCU priority-inversion test
		cycle. Defaults to "test_boost_interval=7". It is
		usually wise for this value to be relatively prime to
		the value selected for "stutter".

		test_boost_duration
		The number of seconds to do RCU priority-inversion testing
		within any given "test_boost_interval". Defaults to
		"test_boost_duration=4".

		test_no_idle_hz Whether or not to test the ability of RCU to operate in
		a kernel that disables the scheduling-clock interrupt to
		idle CPUs. Boolean parameter, "1" to test, "0" otherwise.
		Defaults to omitting this test.

		torture_type The type of RCU to test, with string values as follows:

		"rcu": rcu_read_lock(), rcu_read_unlock() and call_rcu(),
		along with expedited, synchronous, and polling
		variants.

		"rcu_bh": rcu_read_lock_bh(), rcu_read_unlock_bh(), and
		call_rcu_bh(), along with expedited and synchronous
		variants.

		"rcu_busted": This tests an intentionally incorrect version
		of RCU in order to help test rcutorture itself.

		"srcu": srcu_read_lock(), srcu_read_unlock() and
		call_srcu(), along with expedited and
		synchronous variants.

		"sched": preempt_disable(), preempt_enable(), and
		call_rcu_sched(), along with expedited,
		synchronous, and polling variants.

		"tasks": voluntary context switch and call_rcu_tasks(),
		along with expedited and synchronous variants.

		Defaults to "rcu".

		verbose Enable debug printk()s. Default is disabled.

		Module parameters are prefixed by "rcutorture." in
		Documentation/admin-guide/kernel-parameters.txt.

		OUTPUT

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