kernel/git/next/linux-next.git/tools/memory-model/scripts, branch akpm

tools/memory-model: Use "-unroll 0" to keep --hw runs finite

2022-06-20T16:46:22+00:00

Litmus tests involving atomic operations produce LL/SC loops on a number of architectures, and unrolling these loops can result in excessive verification times or even stack overflows. This commit therefore uses the "-unroll 0" herd7 argument to avoid unrolling, on the grounds that additional passes through an LL/SC loop should not change the verification. Note however, that certain bugs in the mapping of the LL/SC loop to machine instructions may go undetected. On the other hand, herd7 might not be the best vehicle for finding such bugs in any case. (You do stress-test your architecture-specific code, don't you?) Suggested-by: Luc Maranget Signed-off-by: Paul E. McKenney

tools/memory-model: Make judgelitmus.sh handle scripted Result: tag

2022-06-20T16:46:22+00:00

The scripts that generate the litmus tests in the "auto" directory of the https://github.com/paulmckrcu/litmus archive place the "Result:" tag into a single-line ocaml comment, which judgelitmus.sh currently does not recognize. This commit therefore makes judgelitmus.sh recognize both the multiline comment format that it currently does and the automatically generated single-line format. Signed-off-by: Paul E. McKenney

tools/memory-model: Add data-race capabilities to judgelitmus.sh

2022-06-20T16:46:22+00:00

This commit adds functionality to judgelitmus.sh to allow it to handle both the "DATARACE" markers in the "Result:" comments in litmus tests and the "Flag data-race" markers in LKMM output. For C-language tests, if either marker is present, the other must also be as well, at least for litmus tests having a "Result:" comment. If the LKMM output indicates a data race, then failures of the Always/Sometimes/Never portion of the "Result:" prediction are forgiven. The reason for forgiving "Result:" mispredictions is that data races can result in "interesting" compiler optimizations, so that all bets are off in the data-race case. [ paulmck: Apply Akira Yokosawa feedback. ] Signed-off-by: Paul E. McKenney

tools/memory-model: Add checktheselitmus.sh to run specified litmus tests

2022-06-20T16:46:22+00:00

This commit adds a checktheselitmus.sh script that runs the litmus tests specified on the command line. This is useful for verifying fixes to specific litmus tests. Signed-off-by: Paul E. McKenney

tools/memory-model: Repair parseargs.sh header comment

2022-06-20T16:46:21+00:00

Signed-off-by: Paul E. McKenney

tools/memory-model: Add "--" to parseargs.sh for additional arguments

2022-06-20T16:46:21+00:00

Currently, parseargs.sh expects to consume all the command-line arguments, which prevents the calling script from having any of its own arguments. This commit therefore causes parseargs.sh to stop consuming arguments when it encounters a "--" argument, leaving any remaining arguments for the calling script. Signed-off-by: Paul E. McKenney

tools/memory-model: Make history-check scripts use mselect7

2022-06-20T16:46:21+00:00

The history-check scripts currently use grep to ignore non-C-language litmus tests, which is a bit fragile. This commit therefore enlists the aid of "mselect7 -arch C", given Luc Maraget's recent modifications that allow mselect7 to operate in filter mode. This change requires herdtools 7.52-32-g1da3e0e50977 or later. Signed-off-by: Paul E. McKenney

tools/memory-model: Make checkghlitmus.sh use mselect7

2022-06-20T16:46:21+00:00

The checkghlitmus.sh script currently uses grep to ignore non-C-language litmus tests, which is a bit fragile. This commit therefore enlists the aid of "mselect7 -arch C", given Luc Maraget's recent modifications that allow mselect7 to operate in filter mode. This change requires herdtools 7.52-32-g1da3e0e50977 or later. Signed-off-by: Paul E. McKenney

tools/memory-model: Fix scripting --jobs argument

2022-06-20T16:46:21+00:00

The parseargs.sh regular expression for the --jobs argument incorrectly requires that the number of jobs be at least 10, that is, have at least two digits. This commit therefore adjusts this regular expression to allow single-digit numbers of jobs to be specified. Signed-off-by: Paul E. McKenney

tools/memory-model: Implement --hw support for checkghlitmus.sh

2022-06-20T16:46:21+00:00

This commits enables the "--hw" argument for the checkghlitmus.sh script, causing it to convert any applicable C-language litmus tests to the specified flavor of assembly language, to verify these assembly-language litmus tests, and checking compatibility of the outcomes. Note that the conversion does not yet handle locking, RCU, SRCU, plain C-language memory accesses, or casts. Signed-off-by: Paul E. McKenney