The edk2 "build" utility natively supports building modules (that is, INF files) in parallel. The feature is not useful when building a single module (with the "-m" option), but it is useful for platform firmware builds (which include many modules). Add a function that determines the "-n" option argument for "build", from the MAKEFLAGS variable (i.e. based on the presence of a make job server).
Signed-off-by: Laszlo Ersek <ler...@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com> Tested-by: Philippe Mathieu-Daudé <phi...@redhat.com> Reviewed-by: Michal Privoznik <mpriv...@redhat.com> Reviewed-by: Michael S. Tsirkin <m...@redhat.com> --- Notes: v2: - pick up Phil's R-b / T-b - pick up Michal's and Michael's R-b's roms/edk2-funcs.sh | 25 ++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/roms/edk2-funcs.sh b/roms/edk2-funcs.sh index d1cb1e4a111e..a9fae7ee891b 100644 --- a/roms/edk2-funcs.sh +++ b/roms/edk2-funcs.sh @@ -226,3 +226,28 @@ qemu_edk2_set_cross_env() eval "export $cross_prefix_var=\$cross_prefix" } + + +# Determine the "-n" option argument (that is, the number of modules to build +# in parallel) for the edk2 "build" utility. Print the result to the standard +# output. +# +# Parameters: +# $1: the value of the MAKEFLAGS variable +qemu_edk2_get_thread_count() +{ + local makeflags="$1" + + if [[ "$makeflags" == *--jobserver-auth=* ]] || + [[ "$makeflags" == *--jobserver-fds=* ]]; then + # If there is a job server, allow the edk2 "build" utility to parallelize + # as many module builds as there are logical CPUs in the system. The "make" + # instances forked by "build" are supposed to limit themselves through the + # job server. The zero value below causes the edk2 "build" utility to fetch + # the logical CPU count with Python's multiprocessing.cpu_count() method. + printf '0\n' + else + # Build a single module at a time. + printf '1\n' + fi +} -- 2.19.1.3.g30247aa5d201