Make it a bit easier to apply KASAN to rcutorture runs with a new --kasan
argument, again leveraging the config_override_param() bash function.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit saves a few lines of code by also using the bash
config_override_param() to set the initial list of Kconfig options from
the CFcommon file. While in the area, it makes this function capable of
update-in-place on the file containing the cumulative Kconfig options,
thus avoiding annoying changes when adding another source of options.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit applies config_override_param() to allow scenario-specific
Kconfig options to override those in CFcommon. This in turn will allow
additional Kconfig options to be placed in CFcommon, for example, an
option common to all but a few scenario can be placed in CFcommon and
then overridden in those few scenarios. Plus this change saves one
whole line of code.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, attempting to override a --kcsan default with a --kconfig
option might or might not work. However, it would be good to allow the
user to adjust the --kcsan defaults, for example, to specify a different
time for CONFIG_KCSAN_REPORT_ONCE_IN_MS. This commit therefore uses the
new config_override_param() bash function to apply the --kcsan defaults
and then apply the --kconfig options, which allows this overriding
to occur.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit introduces a config_override_param() bash function that
folds in an additional set of Kconfig options. This is initially applied
to fold in the --kconfig kvm.sh parameter, but later commits will also
apply it to the Kconfig options added by the --kcsan kvm.sh parameter.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The #CHECK# directives that can be present in CFcommon and in the
rcutorture scenario Kconfig files are both copied to ConfigFragment
and grepped out of the two directive files and added to ConfigFragment.
This commit therefore removes the redundant "grep" commands and takes
advantage of the consequent opportunity to simplify redirection.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The KCSAN tool emits a great many warnings for current kernels, for
example, a one-hour run of the full set of rcutorture scenarios results
in no fewer than 3252 such warnings, many of which are duplicates
or are otherwise closely related. This commit therefore introduces
a kcsan-collapse.sh script that maps these warnings down to a set of
function pairs (22 of them given the 3252 individual warnings), placing
the resulting list in decreasing order of frequency of occurrence into
a kcsan.sum file. If any KCSAN warnings were produced, the pathname of
this file is emitted at the end of the summary of the rcutorture runs.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Although the existing --kconfig argument can be used to run KCSAN for
an rcutorture test, it is not as straightforward as one might like:
--kconfig "CONFIG_DEBUG_INFO=y CONFIG_KCSAN=y \
CONFIG_KCSAN_ASSUME_PLAIN_WRITES_ATOMIC=n \
CONFIG_KCSAN_REPORT_VALUE_CHANGE_ONLY=n \
CONFIG_KCSAN_REPORT_ONCE_IN_MS=100000 \
CONFIG_KCSAN_VERBOSE=y CONFIG_KCSAN_INTERRUPT_WATCHER=y"
This commit therefore adds a "--kcsan" argument that emulates the above
--kconfig command. Note that if you specify a Kconfig option using
-kconfig that conflicts with one that --kcsan adds, you get whatever
the script and the build system decide to give you.
Cc: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
System hangs or killed rcutorture guest OSes can result in truncated
"Reader Pipe:" lines, which can in turn result in false-positive
reader-batch near-miss warnings. This commit therefore adjusts the
reader-batch checks to account for possible line truncation.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, kvm-find-errors.sh gives a usage prompt when given a bad
directory, but then soldiers on, giving a series of confusing error
messages. This commit therefore prints an error message and exits when
given a bad directory, hopefully reducing confusion.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
When running the default list of tests, the run summary of a successful
(that is, failed to find any errors) run fits easily on a 24-line screen.
But a run with something like "--configs '5*CFLIST'" will be 80 lines long,
and it is all too easy to miss a failure message when scrolling back.
This commit therefore prints out the number of runs with failing builds
or runtime failures, but only if there are any such failures.
For example, a run with a single build error and a single runtime error
would print two lines like this:
1 runs with build errors.
1 runs with runtime errors.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The names of the per-test results directories are of the form
2019.11.29-20:42:19. This works, but the ":" characters make
tab-based shell name completion a bit onerous because the user must
remember to include a quote character somewhere before the first ":".
This commit therefore changes the ":" characters to periods, as in
2019.12.01-20.48.01", which allows tab-based completion to work more
naturally.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The bootparam_hotplug_cpu() bash function was checking for CPU-hotplug
kernel-boot parameters from --bootargs, but that check was specific to
rcutorture ("rcutorture\.onoff_"). This commit therefore makes this
check also work for locktorture ("torture\.onoff_").
Note that rcuperf does not do CPU-hotplug operations, so it is not
necessary to make a similar change for rcuperf.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
On some kernels, concurrent calls to the lscpu command result in severe
slowdowns. For example, on v4.16, a single lscpu invocation takes about
two milliseconds, four concurrent invocations more than two seconds,
and 16 concurrent invocations more than 20 seconds. Given that the only
goal is to learn the number of CPUs, invoking lscpu but once suffices.
This commit therefore invokes lscpu early in kvm.sh execution, setting
the initial value of the TORTURE_ALLOTED_CPUS environment variable.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
On a large system, it can be convenient to tell rcutorture to run
several instances of the default scenarios. Currently, this requires
explicitly listing them, for example, "--configs '2*SRCU-N 2*SRCU-P...'".
Although this works, it is rather inconvenient.
This commit therefore allows "CFLIST" to be specified to indicate the
default list of scenarios called out in the relevant CFLIST file, for
example, for RCU, tools/testing/selftests/rcutorture/configs/rcu/CFLIST.
In addition, multipliers may be used to run multiple instances of all
the scenarios. For example, on a 256-CPU system, "--configs '3*CFLIST'"
would run three instances of each scenario concurrently with one CPU
left over. Thus "--configs '3*CFLIST TINY01'" would exactly consume all
256 CPUs, which makes rcutorture's jitter feature more effective.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds the worst-case results from any call_rcu()
forward-progress tests to the rcutorture test-summary output.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcutorture scripting uses the mpstat command to determine how much
the system is being used, and adjusts make's -j argument accordingly.
However, mpstat isn't installed by default, so it would be good if the
scripting does something useful when mpstat isn't present.
This commit therefore makes the scripts assumes that if mpstat is not
present, they are free to use all the CPUs.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, jitter.sh assumes that the underlying hypervisor will be
configured with all CPUs hotpluggable, with the possible exception
of CPU 0. However, there are installations where the hypervisor
prohibits offlining, which breaks jitter.sh. This commit therefore
lists the CPUs that cannot be offlined up front, and checks for the
case where no CPU can be offlined in the loop.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The dracut scripting does not work on all platforms, and there are no
known failures from the init binary based on the statically linked C
program. This commit therefore removes the dracut scripting so that the
statically linked C program is always used to create the init "script".
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In many environments, gawk provides systime(), but awk doesn't.
This commit therefore changes awk scripts using systime() to instead be
gawk scripts.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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. ]
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Paul E. McKenney