2017-11-14 21:35 GMT+09:00 Julia Lawall <julia.lawall@xxxxxxx>: > > > On Tue, 14 Nov 2017, Masahiro Yamada wrote: > >> The command "make -j8 C=1 CHECK=scripts/coccicheck COCCI=..." produces >> lots of "coccicheck failed" error messages. >> >> Julia Lawall explained the Coccinelle behavior as follows: >> "The problem on the Coccinelle side is that it uses a subdirectory >> with the name of the semantic patch to store standard output and >> standard error for the different threads. I didn't want to use a >> name with the pid, so that one could easily find this information >> while Coccinelle is running. Normally the subdirectory is cleaned >> up when Coccinelle completes, so there is only one of them at a time. >> Maybe it is best to just add the pid. There is the risk that these >> subdirectories will accumulate if Coccinelle crashes in a way such >> that they don't get cleaned up, but Coccinelle could print a warning >> if it detects this case, rather than failing." >> >> When scripts/coccicheck is used as CHECK tool and -j option is given >> to Make, the whole of build process runs in parallel. So, multiple >> processes try to get access to the same subdirectory. >> >> I notice spatch creates the subdirectory only when it runs in parallel >> (i.e. --jobs <N> is given and <N> is greater than 1). >> >> Setting NPROC=1 is a reasonable solution; spatch does not create the >> subdirectory. Besides, ONLINE=1 mode takes a single file input for >> each spatch invocation, so there is no reason to parallelize it in >> the first place. >> >> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > Acked-by: Julia Lawall <Julia.Lawall@xxxxxxx> > >> --- >> >> Changes in v4: >> - Remove unnecessary comments. One line comment will be enough. >> >> Changes in v3: >> - Set NPROC=1 because this is a more sensible solution >> given that there is no reason to run coccinelle in parallel >> for ONLINE=1 mode. >> - Move J= option handling to a proper place. >> - Add more detailed explanation >> >> Changes in v2: >> - Grep '-j' instead of '--jobserver-auth'. >> '--jobserver-*' is not a stable option flag. >> Make 4.2 change '--jobserver-fds' into '--jobserver-auth' >> - Add -q option to grep >> >> scripts/coccicheck | 15 +++++++++------ >> 1 file changed, 9 insertions(+), 6 deletions(-) >> >> diff --git a/scripts/coccicheck b/scripts/coccicheck >> index 040a8b1..fefda40 100755 >> --- a/scripts/coccicheck >> +++ b/scripts/coccicheck >> @@ -30,12 +30,6 @@ else >> VERBOSE=0 >> fi >> >> -if [ -z "$J" ]; then >> - NPROC=$(getconf _NPROCESSORS_ONLN) >> -else >> - NPROC="$J" >> -fi >> - >> FLAGS="--very-quiet" >> >> # You can use SPFLAGS to append extra arguments to coccicheck or override any >> @@ -70,6 +64,9 @@ if [ "$C" = "1" -o "$C" = "2" ]; then >> # Take only the last argument, which is the C file to test >> shift $(( $# - 1 )) >> OPTIONS="$COCCIINCLUDE $1" >> + >> + # No need to parallelize Coccinelle since this mode takes one input file. >> + NPROC=1 >> else >> ONLINE=0 >> if [ "$KBUILD_EXTMOD" = "" ] ; then >> @@ -77,6 +74,12 @@ else >> else >> OPTIONS="--dir $KBUILD_EXTMOD $COCCIINCLUDE" >> fi >> + >> + if [ -z "$J" ]; then >> + NPROC=$(getconf _NPROCESSORS_ONLN) >> + else >> + NPROC="$J" >> + fi >> fi >> >> if [ "$KBUILD_EXTMOD" != "" ] ; then >> -- >> 2.7.4 >> >> Applied to linux-kbuild. -- Best Regards Masahiro Yamada -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
