From 05dc8470b3bfcad6b84bcf5953172ce26cfb2bd9 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 26 Jan 2023 15:41:00 -0800 Subject: tools/memory-model: Document LKMM test procedure This commit documents how to run the various scripts in order to test a potentially pervasive change to the memory model. Signed-off-by: Paul E. McKenney --- tools/memory-model/scripts/README | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'tools/memory-model') diff --git a/tools/memory-model/scripts/README b/tools/memory-model/scripts/README index cc2c4e5be9ec..fb39bd0fd1b9 100644 --- a/tools/memory-model/scripts/README +++ b/tools/memory-model/scripts/README @@ -76,3 +76,35 @@ runlitmushist.sh README This file + +Testing a change to LKMM might go as follows: + + # Populate expected results without that change, and + # runs for about an hour on an 8-CPU x86 system: + scripts/initlitmushist.sh --timeout 10m --procs 10 + # Incorporate the change: + git am -s -3 /path/to/patch # Or whatever it takes. + + # Test the new version of LKMM as follows... + + # Runs in seconds, good smoke test: + scripts/checkalllitmus.sh + + # Compares results to those produced by initlitmushist.sh, + # and runs for about an hour on an 8-CPU x86 system: + scripts/checklitmushist.sh --timeout 10m --procs 10 + + # Checks results against Result tags, runs in minutes: + scripts/checkghlitmus.sh --timeout 10m --procs 10 + +The checkghlitmus.sh should not report errors in cases where the +checklitmushist.sh script did not also report a change. However, +this check is nevertheless valuable because it can find errors in the +original version of LKMM. Note however, that given the above procedure, +an error in the original LKMM version that is fixed by the patch will +be reported both as a mismatch by checklitmushist.sh and as an error +by checkghlitmus.sh. One exception to this rule of thumb is when the +test fails completely on the original version of LKMM and passes on the +new version. In this case, checklitmushist.sh will report a mismatch +and checkghlitmus.sh will report success. This happens when the change +to LKMM introduces a new primitive for which litmus tests already existed. -- cgit v1.2.3