Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Although we expect some small discrepancies for very large counts, we
seem to be able to count up to 64 billion instructions without too much
skew, so do so.

Also switch to using decimals for the instruction counts. This just
makes it easier to visually compare the expected vs actual values, as
well as the raw result from instructions.

Before:

  instructions: result 68719476753 running/enabled 13101961654
  cycles: result 38077343785 running/enabled 13101725752
  Looped for 68719476736 instructions, overhead 17
  Expected 68719476753
  Actual   68719476753
  Delta    0, 0.000000%
  success: count_instructions

After:
  instructions: result 64000000016 running/enabled 12197599964
  cycles: result 35412471674 running/enabled 12197534110
  Looped for 64000000000 instructions, overhead 16
  Expected 64000000016
  Actual   64000000016
  Delta    0, 0.000000%
  success: count_instructions
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Have a task eat some cpu while we are counting instructions to create
some scheduler pressure. The idea being to try and unearth any bugs we
have in counting that only appear when context switching is happening.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

There is at least one bug in core_busy_loop(), we use r0, but it's
not in the clobber list. We were getting away with this it seems but
that was luck.

It's also fishy to be touching the stack, even if we do it below the
stack pointer. It seems we get away with it, but looking at the
generated code that may just be luck.

So move it into assembler, do all the stack handling by hand. We create
a stack frame to save the non-volatiles in, so we can muck around with
them.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

start and end should be unsigned long.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Currently we ignore errors from our sub Makefiles. We inherited that
from the top-level selftests Makefile which aims to build and run as
many tests as possible and damn the torpedoes.

For the powerpc tests we'd instead like any errors to fail the build, so
we can automatically catch build failures.

We can achieve the best of both worlds by using -k, which tells make to
keep building when it hits an error, but still reports the error.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This gives us standardised success/failure output and also handles
killing the test if it runs forever (2 minutes).
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The Power8 Performance Monitor Unit (PMU) has a new feature called Event
Based Branches (EBB). This commit adds tests of the kernel API for using
EBBs.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Allows us to kill the test and any children it has spawned.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Correct the DSCR SPR becoming temporarily corrupted if a task is
context switched during a transaction.

The problem occurs while suspending the task and is caused by saving
the DSCR to thread.dscr after it has already been set to the CPU's
default value:

__switch_to() calls __switch_to_tm()
	which calls tm_reclaim_task()
	which calls tm_reclaim_thread()
	which calls tm_reclaim()
		where the DSCR is set to the CPU's default
__switch_to() calls _switch()
		where thread.dscr is set to the DSCR

When the task is resumed, it's transaction will be doomed (as usual)
and the DSCR SPR will be corrupted, although the checkpointed value
will be correct. Therefore the DSCR will be immediately corrected by
the transaction aborting, unless it has been suspended. In that case
the incorrect value can be seen by the task until it resumes the
transaction.

The fix is to treat the DSCR similarly to the TAR and save it early
in __switch_to().

A program exposing the problem is added to the kernel self tests as:
tools/testing/selftests/powerpc/tm/tm-resched-dscr.
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
CC: <stable@vger.kernel.org> [v3.10+]
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This adds several behavioral tests to sysctl string and number writing
to detect unexpected cases that behaved differently when the sysctl
kernel.sysctl_writes_strict != 1.

[ original ]
    root@localhost:~# make test_num
    == Testing sysctl behavior against /proc/sys/kernel/domainname ==
    Writing test file ... ok
    Checking sysctl is not set to test value ... ok
    Writing sysctl from shell ... ok
    Resetting sysctl to original value ... ok
    Writing entire sysctl in single write ... ok
    Writing middle of sysctl after synchronized seek ... FAIL
    Writing beyond end of sysctl ... FAIL
    Writing sysctl with multiple long writes ... FAIL
    Writing entire sysctl in short writes ... FAIL
    Writing middle of sysctl after unsynchronized seek ... ok
    Checking sysctl maxlen is at least 65 ... ok
    Checking sysctl keeps original string on overflow append ... FAIL
    Checking sysctl stays NULL terminated on write ... ok
    Checking sysctl stays NULL terminated on overwrite ... ok
    make: *** [test_num] Error 1
    root@localhost:~# make test_string
    == Testing sysctl behavior against /proc/sys/vm/swappiness ==
    Writing test file ... ok
    Checking sysctl is not set to test value ... ok
    Writing sysctl from shell ... ok
    Resetting sysctl to original value ... ok
    Writing entire sysctl in single write ... ok
    Writing middle of sysctl after synchronized seek ... FAIL
    Writing beyond end of sysctl ... FAIL
    Writing sysctl with multiple long writes ... ok
    make: *** [test_string] Error 1

[ with CONFIG_PROC_SYSCTL_STRICT_WRITES ]
    root@localhost:~# make run_tests
    == Testing sysctl behavior against /proc/sys/kernel/domainname ==
    Writing test file ... ok
    Checking sysctl is not set to test value ... ok
    Writing sysctl from shell ... ok
    Resetting sysctl to original value ... ok
    Writing entire sysctl in single write ... ok
    Writing middle of sysctl after synchronized seek ... ok
    Writing beyond end of sysctl ... ok
    Writing sysctl with multiple long writes ... ok
    Writing entire sysctl in short writes ... ok
    Writing middle of sysctl after unsynchronized seek ... ok
    Checking sysctl maxlen is at least 65 ... ok
    Checking sysctl keeps original string on overflow append ... ok
    Checking sysctl stays NULL terminated on write ... ok
    Checking sysctl stays NULL terminated on overwrite ... ok
    == Testing sysctl behavior against /proc/sys/vm/swappiness ==
    Writing test file ... ok
    Checking sysctl is not set to test value ... ok
    Writing sysctl from shell ... ok
    Resetting sysctl to original value ... ok
    Writing entire sysctl in single write ... ok
    Writing middle of sysctl after synchronized seek ... ok
    Writing beyond end of sysctl ... ok
    Writing sysctl with multiple long writes ... ok
Signed-off-by: NKees Cook <keescook@chromium.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The current scripting only keeps track of the git SHA-1 of the current
HEAD.  This can cause confusion in cases where testing ran in a git
tree where changes had not yet been checked in.  This commit therefore
also records the output of "git diff HEAD" to provide the information
needed to reconstruct the source tree that was tested.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit ensures that RCU-sched primitives are tested in
TREE_PREEMPT_RCU kernels, a combination that was previously omitted.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The kvm-test-1-run.sh currently counts "sleep 1" commands to detect
hangs.  This can fail spectacularly on busy systems, where "sleep 1"
might take far longer than one second to complete.  This commit
therefore changes hang detection to use elapsed time measurements.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The reaction of kvm-recheck.sh is obscure at best, and easy to miss
completely.  This commit therefore prints "BUG: Build failed" in the
summary at the end of a run.  This commit also adds the line of dashes
in cases where performance info is not available, and also avoids
printing nonsense diagnostics in cases where some of the normal test
output is not available.  In addition, this commit saves off the .config
file even when the build fails.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

This commit adds a CONFIG_RCU_TRACE=y version of TREE02 for debugging
purposes.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Currently, the scripts hard-code arch/x86/boot/bzImage, which does not
work well for other architectures.  This commit therefore provides a
identify_boot_image function that selects the correct bzImage location
relative to the top of the Linux source tree.  This commit also adds a
--bootimage argument that allows selecting some other file, for example,
"vmlinux".

This change requires that the definition of the QEMU variable be
computed earlier in order to identify where to look for the boot image
when it comes time to copy it to the results directory.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit applies quotes to permit multi-word --qemu-args and
--bootargs arguments.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The current script does record qemu diagnostics, but the user has to
know where to look for them.  This commit therefore puts them into the
Warnings file so that kvm-recheck.sh will display them.  This change is
especially useful if you are in the habit of killing the qemu process
when you realize that you messed something up, but then later on wonder
why the process terminated early.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

In a normal torture-test run, the script inherits its environment
variables, but this does not work when producing a script that is
to run later.  Therefore, definitions and exports are prepended to
a dryrun script but not to a script that is run immediately.  This
commit reconciles this by placing definitions and exports at the
beginning of the script in both cases.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Conflicts:
	tools/testing/selftests/rcutorture/bin/kvm.sh

The scripts produced by kvm.sh's "--dryrun script" argument were intended
for debugging rather than to run, but it is easier to debug if the script
output matches exactly what is run.  This commit therefore makes this
script runnable.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The torture tests need to set specific values for their respective
Kconfig options (e.g., CONFIG_LOCK_TORTURE_TEST), and must therefore
filter any conflicting definitions from the Kconfig fragment
file.  Unfortunately, the code in kvm-build.sh was looking only for
CONFIG_RCU_TORTURE_TEST.  This commit therefore handles the general case
of CONFIG_[A-Z]*_TORTURE_TEST.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent.
It also removes a redundant export of this same shell variable.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent.
It also drops an redundant "export" statement.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent by
changing RCU_BUILDONLY to TORTURE_BUILDONLY.  It also removes an
unnecessary export command.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent by
changing RCU_KMAKE_ARG to TORTURE_KMAKE_ARG.  It also removes the
unnecessary export command.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Some environments require some variation on "make defconfig" to initialize
the .config file.  This commit therefore adds a --defconfig argument to
allow this to be specified.  The default value is of course "defconfig".
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the torture scripts a bit more RCU-independent.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

It can be a bit jarring to see a locking test complain about RCU, so
this commit renames parse-rcutorture.sh to parse-torture.sh and makes
the messages it emits more generic.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This commit makes the output of "--dryrun sched" more user-friendly,
clearly indicating the batch starts.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The --builddir and --relbuilddir options were initially intended to handle
parallel tests.  However, since commit 43e38ab3 (Enable concurrent
rcutorture runs), the script manages multiple build directories as
needed for parallel testing.  This commit therefore removes these two
obsolete options.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>