From 78ad0693233080169e5a01811bd3fcb3966f2d3f Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 17 Jan 2014 21:56:57 -0800 Subject: [PATCH] rcutorture: Add comments, especially on bin packing. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- tools/testing/selftests/rcutorture/bin/kvm.sh | 33 +++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh index 18649b87ea6c..7ef3b245c778 100644 --- a/tools/testing/selftests/rcutorture/bin/kvm.sh +++ b/tools/testing/selftests/rcutorture/bin/kvm.sh @@ -188,6 +188,7 @@ fi mkdir $resdir/$ds if test "$dryrun" = "" then + # Be noisy only if running the script. echo Results directory: $resdir/$ds echo $scriptname $args fi @@ -201,6 +202,7 @@ then git rev-parse HEAD >> $resdir/$ds/testid.txt fi +# Create a file of test-name/#cpus pairs, sorted by decreasing #cpus. touch $T/cfgcpu for CF in $configs do @@ -214,12 +216,14 @@ do done sort -k2nr $T/cfgcpu > $T/cfgcpu.sort +# Use a greedy bin-packing algorithm, sorting the list accordingly. awk < $T/cfgcpu.sort > $T/cfgcpu.pack -v ncpus=$cpus ' BEGIN { njobs = 0; } { + # Read file of tests and corresponding required numbers of CPUs. cf[njobs] = $1; cpus[njobs] = $2; njobs++; @@ -229,26 +233,40 @@ END { alldone = 0; batch = 0; nc = -1; + + # Each pass through the following loop creates on test batch + # that can be executed concurrently given ncpus. Note that a + # given test that requires more than the available CPUs will run in + # their own batch. Such tests just have to make do with what + # is available. while (nc != ncpus) { batch++; nc = ncpus; + + # Each pass through the following loop considers one + # test for inclusion in the current batch. for (i = 0; i < njobs; i++) { if (done[i]) - continue; + continue; # Already part of a batch. if (nc >= cpus[i] || nc == ncpus) { + + # This test fits into the current batch. done[i] = batch; nc -= cpus[i]; if (nc <= 0) - break; + break; # Too-big test in its own batch. } } } + + # Dump out the tests in batch order. for (b = 1; b <= batch; b++) for (i = 0; i < njobs; i++) if (done[i] == b) print cf[i], cpus[i]; }' +# Generate a script to execute the tests in appropriate batches. awk < $T/cfgcpu.pack \ -v CONFIGDIR="$CONFIGFRAG/$kversion/" \ -v KVM="$KVM" \ @@ -267,6 +285,7 @@ awk < $T/cfgcpu.pack \ i++; } +# Dump out the scripting required to run one test batch. function dump(first, pastlast) { print "echo ----start batch----" @@ -313,23 +332,31 @@ END { njobs = i; nc = ncpus; first = 0; + + # Each pass through the following loop considers one test. for (i = 0; i < njobs; i++) { if (ncpus == 0) { + # Sequential test specified, each test its own batch. dump(i, i + 1); first = i; } else if (nc < cpus[i] && i != 0) { + # Out of CPUs, dump out a batch. dump(first, i); first = i; nc = ncpus; } + # Account for the CPUs needed by the current test. nc -= cpus[i]; } + # Dump the last batch. if (ncpus != 0) dump(first, i); }' > $T/script if test "$dryrun" = script then + # Dump out the script, but define the environment variables that + # it needs to run standalone. echo CONFIGFRAG="$CONFIGFRAG; export CONFIGFRAG" echo KVM="$KVM; export KVM" echo KVPATH="$KVPATH; export KVPATH" @@ -344,10 +371,12 @@ then exit 0 elif test "$dryrun" = sched then + # Extract the test run schedule from the script. egrep 'start batch|Starting build\.' $T/script | sed -e 's/:.*$//' -e 's/^echo //' exit 0 else + # Not a dryru, so run the script. sh $T/script fi -- 2.39.5