diff --git a/Documentation/coccinelle.txt b/Documentation/coccinelle.txt index bb9632c20cfba31a91e18389777a382b3d19b44f..64daaf18874b4557ab71765f1e3d8f698c642c15 100644 --- a/Documentation/coccinelle.txt +++ b/Documentation/coccinelle.txt @@ -94,11 +94,26 @@ To enable verbose messages set the V= variable, for example: make coccicheck MODE=report V=1 + Coccinelle parallelization +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + By default, coccicheck tries to run as parallel as possible. To change the parallelism, set the J= variable. For example, to run across 4 CPUs: make coccicheck MODE=report J=4 +As of Coccinelle 1.0.2 Coccinelle uses Ocaml parmap for parallelization, +if support for this is detected you will benefit from parmap parallelization. + +When parmap is enabled coccicheck will enable dynamic load balancing by using +'--chunksize 1' argument, this ensures we keep feeding threads with work +one by one, so that we avoid the situation where most work gets done by only +a few threads. With dynamic load balancing, if a thread finishes early we keep +feeding it more work. + +When parmap is enabled, if an error occurs in Coccinelle, this error +value is propagated back, the return value of the 'make coccicheck' +captures this return value. Using Coccinelle with a single semantic patch ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/scripts/coccicheck b/scripts/coccicheck index 5319fae910b466ce83b13e8ce2068002f4870d74..4b65a0fd50a118b7ef0563a6498fa6a896eefdec 100755 --- a/scripts/coccicheck +++ b/scripts/coccicheck @@ -12,8 +12,8 @@ if [ ! -x "$SPATCH" ]; then exit 1 fi -trap kill_running SIGTERM SIGINT -declare -a SPATCH_PID +USE_JOBS="no" +$SPATCH --help | grep "\-\-jobs" > /dev/null && USE_JOBS="yes" # The verbosity may be set by the environmental parameter V= # as for example with 'make V=1 coccicheck' @@ -56,6 +56,16 @@ if [ "$KBUILD_EXTMOD" != "" ] ; then OPTIONS="--patch $srctree $OPTIONS" fi +# You can override by using SPFLAGS +if [ "$USE_JOBS" = "no" ]; then + trap kill_running SIGTERM SIGINT + declare -a SPATCH_PID +elif [ "$NPROC" != "1" ]; then + # Using 0 should work as well, refer to _SC_NPROCESSORS_ONLN use on + # https://github.com/rdicosmo/parmap/blob/master/setcore_stubs.c + OPTIONS="$OPTIONS --jobs $NPROC --chunksize 1" +fi + if [ "$MODE" = "" ] ; then if [ "$ONLINE" = "0" ] ; then echo 'You have not explicitly specified the mode to use. Using default "report" mode.' @@ -82,7 +92,18 @@ if [ "$ONLINE" = "0" ] ; then echo '' fi -run_cmd() { +run_cmd_parmap() { + if [ $VERBOSE -ne 0 ] ; then + echo "Running ($NPROC in parallel): $@" + fi + $@ 2>/dev/null + if [[ $? -ne 0 ]]; then + echo "coccicheck failed" + exit $? + fi +} + +run_cmd_old() { local i if [ $VERBOSE -ne 0 ] ; then echo "Running ($NPROC in parallel): $@" @@ -97,6 +118,14 @@ run_cmd() { wait } +run_cmd() { + if [ "$USE_JOBS" = "yes" ]; then + run_cmd_parmap $@ + else + run_cmd_old $@ + fi +} + kill_running() { for i in $(seq 0 $(( NPROC - 1 )) ); do if [ $VERBOSE -eq 2 ] ; then