Re: [Cocci] [PATCH v3] coccinelle: fix parallel build with CHECK=scripts/coccicheck

From: Julia Lawall
Date: Tue Nov 14 2017 - 11:56:02 EST




On Tue, 14 Nov 2017, Luis R. Rodriguez wrote:

> On Tue, Nov 14, 2017 at 06:04:49PM +0900, Masahiro Yamada wrote:
> > diff --git a/scripts/coccicheck b/scripts/coccicheck
> > index 040a8b1..7da82a1 100755
> > --- a/scripts/coccicheck
> > +++ b/scripts/coccicheck
> > @@ -70,6 +64,13 @@ if [ "$C" = "1" -o "$C" = "2" ]; then
> > # Take only the last argument, which is the C file to test
> > shift $(( $# - 1 ))
> > OPTIONS="$COCCIINCLUDE $1"
> > +
> > + # If -j option is given to Make, scripts/coccicheck runs in parallel.
> > + # If coccinelle also runs in parallel, it fails because multiple processes
> > + # try to get access to the same subdirectory that stores stdout/stderr.
> > + # No need to parallelize coccinelle in this case - this mode takes only
> > + # one file input.
> > + NPROC=1
>
> Shouldn't this also warn to the user, and recommend to use a proper form to
> parallelize coccinelle? Otherwise a user might get the impression they are
> parallelizing coccinelle where they really did not.

Coccinelle sees a file at a time when using C=1 or C=2. There is nothing
to parallelize at the Coccinelle level, if you want to use these options.

julia


>
> Luis
>
> > else
> > ONLINE=0
> > if [ "$KBUILD_EXTMOD" = "" ] ; then
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