tools/memory-model: Split runlitmus.sh out of checklitmus.sh

This commit prepares for adding --hw capability to github litmus-test
scripts by splitting runlitmus.sh (which simply runs the verification)
out of checklitmus.sh (which also judges the results).

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/memory-model: Hardware checking for check{,all}litmus.sh

This commit makes checklitmus.sh and checkalllitmus.sh check to see
if a hardware verification was specified (via the --hw command-line
argument, which sets the LKMM_HW_MAP_FILE environment variable).
If so, the C-language litmus test is converted to the specified type
of assembly-language litmus test and herd is run on it. Hardware is
permitted to be stronger than LKMM requires, so "Always" and "Never"
verifications of "Sometimes" C-language litmus tests are forgiven.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/memory-model: Fix paulmck email address on pre-existing scripts

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/memory-model: Do not use "herd" to refer to "herd7"

Use "herd7" in each such reference.

Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

tools/memory-model: Add scripts to check github litmus tests

The https://github.com/paulmckrcu/litmus repository contains a large
number of C-language litmus tests that include "Result:" comments
predicting the verification result. This commit adds a number of scripts
that run tests on these litmus tests:

checkghlitmus.sh:
Runs all litmus tests in the https://github.com/paulmckrcu/litmus
archive that are C-language and that have "Result:" comment lines
documenting expected results, comparing the actual results to
those expected. Clones the repository if it has not already
been cloned into the "tools/memory-model/litmus" directory.

initlitmushist.sh
Run all litmus tests having no more than the specified number
of processes given a specified timeout, recording the results in
.litmus.out files. Clones the repository if it has not already
been cloned into the "tools/memory-model/litmus" directory.

newlitmushist.sh
For all new or updated litmus tests having no more than the
specified number of processes given a specified timeout, run
and record the results in .litmus.out files.

checklitmushist.sh
Run all litmus tests having .litmus.out files from previous
initlitmushist.sh or newlitmushist.sh runs, comparing the
herd output to that of the original runs.

The above scripts will run litmus tests concurrently, by default with
one job per available CPU. Giving any of these scripts the --help
argument will cause them to print usage information.

This commit also adds a number of helper scripts that are not intended
to be invoked from the command line:

cmplitmushist.sh: Compare the output of two different runs of the same
litmus test.

judgelitmus.sh: Compare the output of a litmus test to its "Result:"
comment line.

parseargs.sh: Parse command-line arguments.

runlitmushist.sh: Run the litmus tests whose pathnames are provided one
per line on standard input.

While in the area, this commit also makes the existing checklitmus.sh
and checkalllitmus.sh scripts use parseargs.sh in order to provide a
bit of uniformity. In addition, per-litmus-test status output is directed
to stdout, while end-of-test summary information is directed to stderr.
Finally, the error flag standardizes on "!!!" to assist those familiar
with rcutorture output.

The defaults for the parseargs.sh arguments may be overridden by using
environment variables: LKMM_DESTDIR for --destdir, LKMM_HERD_OPTIONS
for --herdoptions, LKMM_JOBS for --jobs, LKMM_PROCS for --procs, and
LKMM_TIMEOUT for --timeout.

[ paulmck: History-check summary-line changes per Alan Stern feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20181203230451.28921-2-paulmck@linux.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

tools/memory-model: Make scripts executable

This commit makes the scripts executable to avoid the need for everyone
to do so manually in their archive.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Akira Yokosawa <akiyks@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-7-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

tools/memory-model: Add scripts to test memory model

This commit adds a pair of scripts that run the memory model on litmus
tests, checking that the verification result of each litmus test matches
the result flagged in the litmus test itself. These scripts permit easier
checking of changes to the memory model against preconceived notions.

To run the scripts, go to the tools/memory-model directory and type
"scripts/checkalllitmus.sh". If all is well, the last line printed will
be "All litmus tests verified as was expected."

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Link: http://lkml.kernel.org/r/1526340837-12222-9-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>