Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:

 - Lots of tidying up changes all across the map for Linux's formal
   memory/locking-model tooling, by Alan Stern, Akira Yokosawa, Andrea
   Parri, Paul E. McKenney and SeongJae Park.

   Notable changes beyond an overall update in the tooling itself is the
   tidying up of spin_is_locked() semantics, which spills over into the
   kernel proper as well.

 - qspinlock improvements: the locking algorithm now guarantees forward
   progress whereas the previous implementation in mainline could starve
   threads indefinitely in cmpxchg() loops. Also other related cleanups
   to the qspinlock code (Will Deacon)

 - misc smaller improvements, cleanups and fixes all across the locking
   subsystem

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  locking/rwsem: Simplify the is-owner-spinnable checks
  tools/memory-model: Add reference for 'Simplifying ARM concurrency'
  tools/memory-model: Update ASPLOS information
  MAINTAINERS, tools/memory-model: Update e-mail address for Andrea Parri
  tools/memory-model: Fix coding style in 'lock.cat'
  tools/memory-model: Remove out-of-date comments and code from lock.cat
  tools/memory-model: Improve mixed-access checking in lock.cat
  tools/memory-model: Improve comments in lock.cat
  tools/memory-model: Remove duplicated code from lock.cat
  tools/memory-model: Flag "cumulativity" and "propagation" tests
  tools/memory-model: Add model support for spin_is_locked()
  tools/memory-model: Add scripts to test memory model
  tools/memory-model: Fix coding style in 'linux-kernel.def'
  tools/memory-model: Model 'smp_store_mb()'
  tools/memory-order: Update the cheat-sheet to show that smp_mb__after_atomic() orders later RMW operations
  tools/memory-order: Improve key for SELF and SV
  tools/memory-model: Fix cheat sheet typo
  tools/memory-model: Update required version of herdtools7
  tools/memory-model: Redefine rb in terms of rcu-fence
  tools/memory-model: Rename link and rcu-path to rcu-link and rb
  ...

1 files changed, 86 insertions, 0 deletions

diff --git a/tools/memory-model/scripts/checklitmus.sh b/tools/memory-model/scripts/checklitmus.sh
new file mode 100644
index 000000000000..e2e477472844
--- /dev/null
+++ b/tools/memory-model/scripts/checklitmus.sh
@@ -0,0 +1,86 @@
+#!/bin/sh
+#
+# Run a herd test and check the result against a "Result:" comment within
+# the litmus test.  If the verification result does not match that specified
+# in the litmus test, this script prints an error message prefixed with
+# "^^^" and exits with a non-zero status.  It also outputs verification
+# results to a file whose name is that of the specified litmus test, but
+# with ".out" appended.
+#
+# Usage:
+#	sh checklitmus.sh file.litmus
+#
+# The LINUX_HERD_OPTIONS environment variable may be used to specify
+# arguments to herd, which default to "-conf linux-kernel.cfg".  Thus,
+# one would normally run this in the directory containing the memory model,
+# specifying the pathname of the litmus test to check.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, you can access it online at
+# http://www.gnu.org/licenses/gpl-2.0.html.
+#
+# Copyright IBM Corporation, 2018
+#
+# Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+
+litmus=$1
+herdoptions=${LINUX_HERD_OPTIONS--conf linux-kernel.cfg}
+
+if test -f "$litmus" -a -r "$litmus"
+then
+	:
+else
+	echo ' --- ' error: \"$litmus\" is not a readable file
+	exit 255
+fi
+if grep -q '^ \* Result: ' $litmus
+then
+	outcome=`grep -m 1 '^ \* Result: ' $litmus | awk '{ print $3 }'`
+else
+	outcome=specified
+fi
+
+echo Herd options: $herdoptions > $litmus.out
+/usr/bin/time herd7 -o ~/tmp $herdoptions $litmus >> $litmus.out 2>&1
+grep "Herd options:" $litmus.out
+grep '^Observation' $litmus.out
+if grep -q '^Observation' $litmus.out
+then
+	:
+else
+	cat $litmus.out
+	echo ' ^^^ Verification error'
+	echo ' ^^^ Verification error' >> $litmus.out 2>&1
+	exit 255
+fi
+if test "$outcome" = DEADLOCK
+then
+	echo grep 3 and 4
+	if grep '^Observation' $litmus.out | grep -q 'Never 0 0$'
+	then
+		ret=0
+	else
+		echo " ^^^ Unexpected non-$outcome verification"
+		echo " ^^^ Unexpected non-$outcome verification" >> $litmus.out 2>&1
+		ret=1
+	fi
+elif grep '^Observation' $litmus.out | grep -q $outcome || test "$outcome" = Maybe
+then
+	ret=0
+else
+	echo " ^^^ Unexpected non-$outcome verification"
+	echo " ^^^ Unexpected non-$outcome verification" >> $litmus.out 2>&1
+	ret=1
+fi
+tail -2 $litmus.out | head -1
+exit $ret