Commit Graph

283 Commits

Author SHA1 Message Date
Paul E. McKenney
f4e8352928 rcutorture: Test TREE03 with the threadirqs kernel boot parameter
Since commit 05f415715c ("rcu: Speed up expedited GPs when interrupting
RCU reader") in v5.0 and through v5.1, booting with the threadirqs kernel
boot parameter caused self-deadlocks, which can be reproduced using the
following command on an 8-CPU system:

tools/testing/selftests/rcutorture/bin/kvm.sh --duration 5 --configs "TREE03" --bootargs "threadirqs"

This commit therefore adds the threadirqs kernel boot parameter to
the TREE03 rcutorture scenario in order to more quickly detect future
similar bugs.

Link: http://lkml.kernel.org/r/20190626135447.y24mvfuid5fifwjc@linutronix.de
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Joel Fernandes <joel@joelfernandes.org>
2019-08-01 14:30:22 -07:00
Paul E. McKenney
2c667e5eae torture: Expand last_ts variable in kvm-test-1-run.sh
The kvm-test-1-run.sh script says 'test -z "last_ts"' which always
evaluates to true (AKA zero) regardless of the value of the last_ts shell
variable.  This commit therefore inserts the needed dollar sign ("$").

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-08-01 14:30:22 -07:00
Paul E. McKenney
8997e6311e torture: Suppress propagating trace_printk() warning
When trace_printk() is used, a message including "BUG" is printed to
the console, which fools the rcutorture scripting into believing that
the corresponding test scenario failed.  This commit therefore filters
out this particular instance of "BUG", thus avoiding the false-positive
test-failure report.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
b93c765fda torture: Add --trust-make to suppress "make clean"
The current rcutorture scripts unconditionally do "make clean", which is
a good way of getting the needed testing done despite any imperfections in
Makefile dependency tracking.  However, this can be a bit irritating when
repeatedly running a single scenario after small changes, for example,
when debugging a problem that affects only a single scenario.  This commit
therefore adds a --trust-make argument that suppresses the "make clean".

Even when using ccache, this speeds up kernel builds by up to almost an
order of magnitude on my laptop.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
7225c07772 torture: Make --cpus override idleness calculations
Currently, rcutorture will use relatively few CPUs to build the kernel
on a busy system, which is often as it should be.  However, if the user
has used the --cpus argument to dedicate a specified number of CPUs to
this torture test, it would be good if the kernel build also made use
of them.  This commit therefore changes the cpus2use.sh script to use
--cpus when specified and to do the idleness calculations otherwise.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
6dc82595ef torture: Run kernel build in source directory
For historical reasons, rcutorture places its build products in a
tools/testing/selftests/rcutorture/b1 directory using the O= kbuild
command-line argument.  However, doing this requires that the source
directory be pristine: Not just "make clean" pristine, but instead "make
mrproper" (or, equivalently, "make distclean") pristine.  Therefore,
rcutorture executes a "make mrproper" before each build.  Unfortunately,
"make mrproper" has the side effect of removing pretty much everything,
including tags files and cscope databases, which can be inconvenient
to people whose workflow centers around a single source tree.

This commit therefore makes rcutorture do the build directly in the
source directory, removing the need for "make mrproper".  This works
because all needed build products are moved to their proper place in the
"res" directory immediately after the build completes, so that multiple
rcutorture kernels can still run concurrently.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
cd6cb7c8a5 torture: Add function graph-tracing cheat sheet
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
7dedfd4335 torture: Capture qemu output
Currently qemu output appears on standard output, but is inaccessible
later on.  This commit therefore captures this output and causes
kvm-recheck.sh to output this output if QEMU gave a non-zero non-137
exit code.  (And exit code of 137 indicates that QEMU was killed, in
which case we want to know about the hang rather than the fact that
QEMU was killed.)

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Sebastian Andrzej Siewior
a6fda6dab9 rcutorture: Tweak kvm options
In one of my rcutorture tests the TSC clocksource got marked unstable
due to a large difference in the TSC value. I'm not sure if the guest
run for a long time with disabled interrupts or if the host was very
busy and didn't schedule the guest for some time.

I took a look on the qemu/KVM options and decided to update the options:

- Use kvm{32|64} as CPU. We could probably use `host' (like ARM does)
  for maximum available features but since we don't run any userland I'm
  not sure if it makes any difference.

- Drop the "noapic" option. There is no history why the APIC was disabled,
  I see no reason for it.  Once old qemu versions fade away, we can add
  "x2apic=on,tsc-deadline=on,hypervisor=on,tsc_adjust=on".

- Additional config options. It ensures that the kernel knowns that it
  runs as a kvm guest and can use virt devices like the kvm-clock as
  clocksource. The kvm-clock was the main motivation here.

- I didn't add a random HW device. It would make the random device ready
  earlier (not it doesn't complete the initialisation at all) but I
  doubt that there is any need for this.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ paulmck: The world is not quite ready for CONFIG_PARAVIRT_SPINLOCKS=y
  and x2apic, so they are omitted for the time being. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
c682db558e rcutorture: Add trivial RCU implementation
I have been showing off a trivial RCU implementation for non-preemptive
environments for some time now:

	#define rcu_read_lock()
	#define rcu_read_unlock()
	#define rcu_dereference(p) READ_ONCE(p)
	#define rcu_assign_pointer(p, v) smp_store_release(&(p), (v))
	void synchronize_rcu(void)
	{
	int cpu;
		for_each_online_cpu(cpu)
			sched_setaffinity(current->pid, cpumask_of(cpu));
	}

Trivial or not, as the old saying goes, "if it ain't tested, it don't
work!".  This commit therefore adds a "trivial" flavor to rcutorture
and a corresponding TRIVIAL test scenario.  This variant does not handle
CPU hotplug, which is unconditionally enabled on x86 for post-v5.1-rc3
kernels, which is why the TRIVIAL.boot says "rcutorture.onoff_interval=0".
This commit actually does handle CONFIG_PREEMPT=y kernels, but only
because it turns back the Linux-kernel clock in order to provide these
alternative definitions (or the moral equivalent thereof):

	#define rcu_read_lock() preempt_disable()
	#define rcu_read_unlock() preempt_enable()

In CONFIG_PREEMPT=n kernels without debugging, these are equivalent to
empty macros give or take a compiler barrier.  However, the have been
successfully tested with actual empty macros as well.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
[ paulmck: Fix symbol issue reported by kbuild test robot <lkp@intel.com>. ]
[ paulmck: Work around sched_setaffinity() issue noted by Andrea Parri. ]
[ paulmck: Add rcutorture.shuffle_interval=0 to TRIVIAL.boot to fix
  interaction with shuffler task noted by Peter Zijlstra. ]
Tested-by: Andrea Parri <andrea.parri@amarulasolutions.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
52b23be7ee rcutorture: Exempt TREE01 from forward-progress testing
Because TREE01 can end up running more vCPUs that physical CPUs,
hammering these shortchanged CPUs with tight loops containing call_rcu()
invocations seems a bit like overkill.  This commit therefore exempts
TREE01 from rcutorture's forward-progress testing.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
2456a8562b rcutorture: Provide rudimentary Makefile
This commit provides a rudimentary Makefile that runs a 10-minute
rcutorture test on scenario TREE01.  This must be run on a system capable
of spawning virtual machines and with everything installed to permit
building Linux kernels.

Reported-by: Shuah Khan <shuah@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Paul E. McKenney
63b29eaed6 torture: Make kvm-find-errors.sh and kvm-recheck.sh provide exit status
This commit causes both kvm-find-errors.sh and kvm-recheck.sh to provide
an exit status based on whether or not errors were located.  In the
case of kvm-recheck.sh, this will be the error status of the last run.
This change allows these commands to be used in scripting and Makefiles
to automatically report failed rcutorture runs.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Joel Fernandes (Google)
dd064c3599 rcutorture: Add cpu0 to the set of CPUs to add jitter
jitter.sh currently does not add CPU0 to the list of CPUs for adding of
jitter. Let us add it to this list even when it is not hot-pluggable.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Joel Fernandes (Google)
e0e2147c1a rcutorture: Select from only online CPUs
The rcutorture jitter.sh script selects a random CPU but does not check
if it is offline or online. This leads to taskset errors many times. On
my machine, hyper threading is disabled so half the cores are offline
causing taskset errors a lot of times. Let us fix this by checking from
only the online CPUs on the system.

Cc: rcu@vger.kernel.org
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:06:09 -07:00
Linus Torvalds
67a2422239 for-5.2/block-20190507
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Merge tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Nothing major in this series, just fixes and improvements all over the
  map. This contains:

   - Series of fixes for sed-opal (David, Jonas)

   - Fixes and performance tweaks for BFQ (via Paolo)

   - Set of fixes for bcache (via Coly)

   - Set of fixes for md (via Song)

   - Enabling multi-page for passthrough requests (Ming)

   - Queue release fix series (Ming)

   - Device notification improvements (Martin)

   - Propagate underlying device rotational status in loop (Holger)

   - Removal of mtip32xx trim support, which has been disabled for years
     (Christoph)

   - Improvement and cleanup of nvme command handling (Christoph)

   - Add block SPDX tags (Christoph)

   - Cleanup/hardening of bio/bvec iteration (Christoph)

   - A few NVMe pull requests (Christoph)

   - Removal of CONFIG_LBDAF (Christoph)

   - Various little fixes here and there"

* tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block: (164 commits)
  block: fix mismerge in bvec_advance
  block: don't drain in-progress dispatch in blk_cleanup_queue()
  blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release
  blk-mq: always free hctx after request queue is freed
  blk-mq: split blk_mq_alloc_and_init_hctx into two parts
  blk-mq: free hw queue's resource in hctx's release handler
  blk-mq: move cancel of requeue_work into blk_mq_release
  blk-mq: grab .q_usage_counter when queuing request from plug code path
  block: fix function name in comment
  nvmet: protect discovery change log event list iteration
  nvme: mark nvme_core_init and nvme_core_exit static
  nvme: move command size checks to the core
  nvme-fabrics: check more command sizes
  nvme-pci: check more command sizes
  nvme-pci: remove an unneeded variable initialization
  nvme-pci: unquiesce admin queue on shutdown
  nvme-pci: shutdown on timeout during deletion
  nvme-pci: fix psdt field for single segment sgls
  nvme-multipath: don't print ANA group state by default
  nvme-multipath: split bios with the ns_head bio_set before submitting
  ...
2019-05-07 18:14:36 -07:00
Christoph Hellwig
72deb455b5 block: remove CONFIG_LBDAF
Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures.  These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time.  Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.

Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-06 10:48:35 -06:00
Paul E. McKenney
164a4daaea torture: Suppress false-positive CONFIG_INITRAMFS_SOURCE complaint
The scripting must supply the CONFIG_INITRAMFS_SOURCE Kconfig option
so that kbuild can find the desired initrd, but the configcheck.sh
script gets confused by this option because it takes a string instead
of the expected y/n/m.  This causes checkconfig.sh to complain about
CONFIG_INITRAMFS_SOURCE in the torture-test output (though not in the
summary).  As more people use rcutorture, the resulting confusion is
an increasing concern.

This commit therefore suppresses this false-positive warning by filtering
CONFIG_INITRAMFS_SOURCE from within the checkconfig.sh script.

Reported-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-03-26 14:42:53 -07:00
Paul E. McKenney
fef141f619 tools/.../rcutorture: Convert to SPDX license identifier
Replace the license boiler plate with a SPDX license identifier.
While in the area, update an email address and add copyright notices.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-03-26 14:42:53 -07:00
Willy Tarreau
30ca20517a tools headers: Move the nolibc header from rcutorture to tools/include/nolibc/
As suggested by Ingo, this header file might benefit other tools than
just rcutorture. For now it's quite limited, but is easy to extend, so
exposing it into tools/include/nolibc/ will make it much easier to
adopt by other tools.

The mkinitrd.sh script in rcutorture was updated to use this new location.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:37:13 -08:00
Willy Tarreau
cc72a50994 rcutorture/nolibc: Add a bit of documentation to explain how to use nolibc
Ingo rightfully asked for a bit more documentation in the nolibc header,
so this patch adds some explanation about its purpose, how it's made, and
how to use it.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2019-01-25 15:37:13 -08:00
Willy Tarreau
85ebb12c4e rcutorture/nolibc: Fix some poor indentation and alignment
A few macros had their rightmost backslash misaligned, and the pollfd
struct definition resisted the previous code reindent. Nothing else
changed.

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com>
2019-01-25 15:37:12 -08:00
Willy Tarreau
f90a66d685 rcutorture/nolibc: Fix the clobbered registers in the MIPS syscall definition
A last-minute checkpatch cleanup caused most of list of clobbered
registers to be lost in the MIPS syscall definition. Although this code
is not yet used on MIPS, it is nevertheless better to fix it before it
does get used.

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:37:11 -08:00
Paul E. McKenney
0d8a9ea976 torture: Explain and simplify odd "for" loop in mkinitrd.sh
Why a Bourne-shell "for" loop?  And why 192 instances of "a"?  This commit
adds a shell comment to present the answer to these mysteries.  It also
uses a series of factor-of-four Bourne-shell assignments to make it
easy to see how many instances there are, replacing the earlier wall of
'a' characters.

Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
[ paulmck: Fix wrong-variable bugs noted by Andrea Parri. ]
2019-01-25 15:37:09 -08:00
Paul E. McKenney
eaaf055f27 Merge branches 'bug.2018.11.12a', 'consolidate.2018.12.01a', 'doc.2018.11.12a', 'fixes.2018.11.12a', 'initrd.2018.11.08b', 'sil.2018.11.12a' and 'srcu.2018.11.27a' into HEAD
bug.2018.11.12a:  Get rid of BUG_ON() and friends
consolidate.2018.12.01a:  Continued RCU flavor-consolidation cleanup
doc.2018.11.12a:  Documentation updates
fixes.2018.11.12a:  Miscellaneous fixes
initrd.2018.11.08b:  Automate creation of rcutorture initrd
sil.2018.11.12a:  Remove more spin_unlock_wait() calls
2018-12-01 12:43:16 -08:00
Paul E. McKenney
df56e0f960 rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu().  This commit therefore makes this change,
even though it is but a comment.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2018-12-01 12:38:52 -08:00
Willy Tarreau
b94ec36896 rcutorture: Make use of nolibc when available
This reduces the size of the init executable from ~800 kB to ~800 bytes
on x86_64. This is only implemented for x86_64, i386, arm and arm64.
Others not tested.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Willy Tarreau
66b6f755ad rcutorture: Import a copy of nolibc
This is a definition of the most common syscalls needed in minimalist
init executables, allowing to statically build them with no external
dependencies. It is sufficient in its current form to build rcutorture's
init on x86_64, i386, arm, and arm64. Others have not been ported or
tested. Updates may be found here :

     http://git.formilux.org/?p=people/willy/nolibc.git

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Willy Tarreau
825fa4cdfb rcutorture: Check initrd/init instead of initrd only
If the build fails, we can end up with an empty initrd directory which
prevents the build script from operating again. Better rely on the
resulting init executable instead.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Willy Tarreau
18d7bf8ed3 rcutorture: Always strip using the cross-compiler
Strip using -s on the compiler command line instead of calling the "strip"
utility as the latter isn't necessarily compatible with the target arch.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
70e9f50477 rcutorture: Add cross-compile capability to initrd.sh
This adds the CROSS_COMPILE environment to the initrd.sh script's
gcc command to enable cross compilation.

Reported-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
229ab0cb5b rcutorture: Make initrd/init execute in userspace
Currently, the initrd/init script and executable remain blocked almost
all the time.  However, it is necessary to test nohz_full userspace
execution, which both variants of initrd/init fail to do.  This commit
therefore causes initrd/init to spend about a millisecond per second
executing in userspace.

Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
38e630424b rcutorture: Add initrd support for systems lacking dracut
The support for creating initrd directories using dracut is a great
improvement over having to always hand-create them, it is a bit annoying
to have to install some otherwise irrelevant package just to be able to
run rcutorture.  This commit therefore adds support for creating initrd
directories on systems innocent of dracut.  You do need gcc, but then
again you need that to build the kernel (or to build llvm) in any case.

The idea is to create an initrd directory containing nothing but a
statically linked binary having a for-loop over a long-term sleep().
The result is a Linux kernel with almost no userspace: even the
time-honored /dev, /lib, /tmp, and /usr directories are gone.  In fact,
the only directory present is "/", but only because I don't know how to
get rid of it, at least short of not having an initrd in the first place.
Although statically linked binaries are much maligned, and rightly so,
their disadvantages seem to be irrelevant for this particular use case.
From https://www.akkadia.org/drepper/no_static_linking.html:

1.	Fixes are difficult to apply to hordes of widely scattered
	statically linked binaries.  But in this case, there is only one
	binary, but there would otherwise be no fewer than four libraries.

2.	Security measures like local address randomization cannot be used.
	Prudence prevents me from asserting that it is impossible to
	base a remote attack on a networking-free rcutorture instance.
	Nevertheless, bonus points to the first person who comes up with
	such an attack!

3.	More efficient use of physical memory.  Not in this case, given
	that libc is 1.8MB and the statically linked binary "only" 800K.

4.	Features such as locales, name service switch (NSS),
	internationalized domain names (IDN) tool, and so on require
	dynamic linking.  Bonus points to the first person coming up
	with a valid rcutorture use case requiring these features in
	its initrd.

5.	Accidental violations of (L)GPL.  Actually, this change actually
	helps -avoid- such violations by reducing the temptation to
	pass around tarballs of rcutorture-ready initrd directories.
	After all, the rcutorture scripts automatically create an initrd
	directory for you, so why bother with the tarballs?

6.	Tools and hacks like ltrace, LD_PRELOAD, LD_PROFILE, and LD_AUDIT
	don't work.  Again, bonus points to the first person coming up
	with a valid rcutorture use case requiring these features in
	its initrd.

Nevertheless, the script will use dracut if available, and will create the
statically linked binary only when dracut are missing.  Those preferring
the smaller initrd directory resulting from the statically linked binary
(like me) are free to hand-edit mkinitrd.sh to remove the code using
dracut.  ;-)

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Connor Shu
8f15c682ac rcutorture: Automatically create initrd directory
The rcutorture scripts currently expect the user to create the
tools/testing/selftests/rcutorture/initrd directory.  Should the user
fail to do this, the kernel build will fail with obscure and confusing
error messages.  This commit therefore adds explicit checks for the
tools/testing/selftests/rcutorture/initrd directory, and if not present,
creates one on systems on which dracut is installed.  If this directory
could not be created, a less obscure error message is emitted and the
test is aborted.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Connor Shu <Connor.Shu@ibm.com>
[ paulmck: Adapt the script to fit into the rcutorture framework and
  severely abbreviate the initrd/init script. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
b56ada1209 Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' and 'torture.2018.08.29a' into HEAD
doc.2018.08.30a: Documentation updates
dynticks.2018.08.30b: RCU flavor consolidation updates and cleanups
srcu.2018.08.30b: SRCU updates
torture.2018.08.29a: Torture-test updates
2018-08-30 16:12:53 -07:00
Paul E. McKenney
55cda2290b rcutorture: Test early boot call_srcu()
Now that SRCU permits call_srcu() to be invoked at early boot, this
commit ensures that the rcutorture scripting tests early boot call_srcu().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:10:38 -07:00
Paul E. McKenney
72ce30dd1f rcu: Stop testing RCU-bh and RCU-sched
Now that the RCU-bh and RCU-sched update-side functions are simple
wrappers around their RCU counterparts, there isn't a whole lot of
point in testing them.  This commit therefore removes the self-test
capability and removes the corresponding kernel-boot parameters.
It also updates the various rcutorture .boot files to remove the
kernel boot parameters that call for testing RCU-bh and RCU-sched.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:29 -07:00
Paul E. McKenney
a52d14addf rcutorture: Remove TREE06 and TREE08 from the default test list
Now that there is only one RCU flavor to rule them all, the TREE06
and TREE08 test scenarios are redundant.  This commit therefore removes
them.  Later changes will rebalance and renumber the tests.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-29 09:20:48 -07:00
Paul E. McKenney
31e7490741 torture: Stop overwriting Make.out file with obsolete version
The old approach placed all the build products into the b* directories,
which meant that some of these build products needed to be copied to
the proper directory in the res hierarchy.  The new approach leaves
things like .config and the .o files in the b1 directory, but directs
build output and diagnostics directly to the proper directory in the
res hierarchy.  Unfortunately, one of the copies was still carried out,
which could (and sometimes did) overwrite the build output and diagnostics
with obsolete output remaining in the b1 directory.

This commit therefore removes the offending "cp" command.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-29 09:20:48 -07:00
Paul E. McKenney
028be12b29 rcutorture: Change units of onoff_interval to jiffies
Some RCU bugs have been sensitive to the frequency of CPU-hotplug
operations, which have been gradually increased over time.  But this
frequency is now at the one-second lower limit that can be specified using
the rcutorture.onoff_interval kernel parameter.  This commit therefore
changes the units of rcutorture.onoff_interval from seconds to jiffies,
and also sets the value specified for this kernel parameter in the TREE03
rcutorture scenario to 200, which is 200 milliseconds for HZ=1000.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12 15:42:01 -07:00
Paul E. McKenney
f34f2f5852 rcu: Move grace-period pre-init delay after pre-init
The main race with the early part of grace-period initialization appears
to be with CPU hotplug.  To more fully open this race window, this commit
moves the rcu_gp_slow() from the beginning of the early initialization
loop to follow that loop, thus widening the race window, especially for
the rcu_node structures that are initialized last.  This commit also
expands rcutree.gp_preinit_delay from 3 to 12, giving the same overall
delay in the grace period, but concentrated in the spot where it will
do the most good.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12 15:39:06 -07:00
Paul E. McKenney
b4c1906f65 rcutorture: Make kvm-find-errors.sh find close calls
Although warnings about close calls are printed by kvm-recheck.sh,
kvm-find-errors.sh currently ignores them.  This could easily result
in someone failing to investigate close calls, so this commit makes
them visible to kvm-find-errors.sh.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25 11:30:10 -07:00
Paul E. McKenney
69409750b2 rcutorture: Remove obsolete TREE08-T.boot file
The TREE08-T.boot file was used to provide alternative options for
debugging, but things have changed, it has not kept up, and it has not
been used or missed.  This commit therefore removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25 11:30:10 -07:00
Paul E. McKenney
5bfd7d34fe torture: Use a single build directory for torture scenarios
The torture scripting currently builds each kernel from a set of parallel
runs in its own build directory.  This can waste quite a bit of space when
running large numbers of concurrent scenarios, and pointlessly given that
the builds are run sequentially (albeit with a largish -j number passed to
"make").  This commit therefore places all build-command output in the
results directory, then does all builds in a single "b1" build directory.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25 11:30:10 -07:00
Paul E. McKenney
da1a1e1923 torture: Make kvm-find-errors.sh find build warnings
Currently, kvm-find-errors.sh looks only for build errors ("error:"),
so this commit makes it also locate build warnings ("warning:").

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:25 -07:00
Paul E. McKenney
b4e8afbd21 rcutorture: Abbreviate kvm.sh summary lines
With the addition of the end-of-test state, it is not uncommon for the
kvm.sh summary lines to overflow 80 characters.  This commit therefore
applies abbreviations in order to make the line fit into 80 characters
with high probability.

And yes, I did make heavy use of punched cards back in the day, so 80
columns it is for my xterms!  ;-)

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:17 -07:00
Paul E. McKenney
413e5512bc rcutorture: Print end-of-test state in kvm.sh summary
This commit adds the end-of-test test, if present in the console output,
to the kvm.sh test summary that is printed by kvm-recheck.sh.  Note that
this only applies to rcutorture console output.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:13 -07:00
Paul E. McKenney
d600e06ba7 torture: Fold parse-torture.sh into parse-console.sh
The rcutorture scripting scans the console output twice, once to look
for various sorts of hangs and again to find warnings and panics.
Unfortunately, only the output of the second scan gets written to the
console.log.diags file, which can cause hangs to be overlooked.
This commit therefore folds the parse-torture.sh script (which looks
for hangs) into the parse-console.sh script (which looks for warnings
and panics).  This allows both types of failure information to be
added to console.log.diags, while still reliably removing this file
when it proves to be empty.

This also fixes a long-standing bug where rcuperf log files would
unconditionally complain about a hang.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:04 -07:00
Paul E. McKenney
95ce5f29e1 torture: Add a script to edit output from failed runs
This commit adds a script that allows viewing the build and/or
console output from failed rcutorture, locktorture, or rcuperf runs.
This replaces a time-honored but inefficient manual procedure that uses
cut and paste.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:31:52 -07:00
Paul E. McKenney
338c46403f Merge branches 'fixes.2018.02.23a', 'srcu.2018.02.20a' and 'torture.2018.02.20a' into HEAD
fixes.2018.02.23a: Miscellaneous fixes
srcu.2018.02.20a: SRCU updates
torture.2018.02.20a: Torture-test updates
2018-02-23 15:15:41 -08:00