> On 2023-08-04 15:43:42+0800, Zhangjin Wu wrote: > > Hi, Thomas > > > > > On 2023-08-03 22:45:52+0800, Zhangjin Wu wrote: > > > > To avoid pollute the source code tree and avoid mrproper for every > > > > architecture switch, the O= argument must be supported. > > > > > > > > Both IMAGE and .config are from the building directory, let's use > > > > objtree instead of srctree for them. > > > > > > > > If no O= option specified, means building kernel in source code tree, > > > > objtree should be srctree in such case. > > > > > > > > Suggested-by: Willy Tarreau <w@xxxxxx> > > > > Link: https://lore.kernel.org/lkml/ZK0AB1OXH1s2xYsh@xxxxxx/ > > > > Signed-off-by: Zhangjin Wu <falcon@xxxxxxxxxxx> > > > > --- > > > > tools/testing/selftests/nolibc/Makefile | 7 +++++-- > > > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile > > > > index 51fef5e6a152..af590aee063a 100644 > > > > --- a/tools/testing/selftests/nolibc/Makefile > > > > +++ b/tools/testing/selftests/nolibc/Makefile > > > > @@ -9,6 +9,9 @@ ifeq ($(srctree),) > > > > srctree := $(patsubst %/tools/testing/selftests/,%,$(dir $(CURDIR))) > > > > endif > > > > > > > > +# add objtree for O= argument, required by IMAGE and .config > > > > +objtree ?= $(srctree) > > > > > > Isn't this already set by the included tools/scripts/Makefile.include? > > > > > > > Good question, but it is empty if no O= specified, checked it several > > times before ;-) > > For me it is not empty when I am in tools/testing/selftests/nolibc/. > Interesting, here is the code I added to check the value: diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile index 22f1e1d73fa8..1ae19e896e24 100644 --- a/tools/testing/selftests/nolibc/Makefile +++ b/tools/testing/selftests/nolibc/Makefile @@ -12,6 +12,8 @@ include $(srctree)/scripts/subarch.include ARCH = $(SUBARCH) endif +$(error objtree=$(objtree), srctree=$(srctree)) + Whenever I do defconfig or run, $ make help Makefile:15: *** objtree=, srctree=/labs/linux-lab/src/linux-stable. Stop. It is only not empty when we pass O explicitly: $ mkdir out $ make help O=out Makefile:15: *** objtree=out, srctree=/labs/linux-lab/src/linux-stable. Stop. $ make help O=$PWD/out Makefile:15: *** objtree=/labs/linux-lab/src/linux-stable/tools/testing/selftests/nolibc/out, srctree=/labs/linux-lab/src/linux-stable. Stop. > > > Also I'm not entirely if O= works as intended currently. > > > When using O=foo in the $LINUX/tools/testing/selftests/nolibc directory > > > > It does work, I have used it to test all of the run targets of the > > tinyconfig patches like this: > > > > $ make run O=kernel-$arch RUN_OUT=run.$arch.out ... > > > > Everything about the kernel will be built in $(O). > > It does not work for me: > > $ cd $HOME/src/linux/tools/testing/selftests/nolibc > $ make O=out kernel > ../../../scripts/Makefile.include:4: *** O=out does not exist. Stop. > $ mkdir out > $ make O=out kernel > ... Stuff happens > ... all the output is in $HOME/src/linux/out not in > tools/testing/selftests/nolibc/out where I would expect it. > The new out directory for which an error was reported before is > completely empty. > Oh, yeah, my fault, I have always used the absolute path, but pasted a relative one above, this is the one I really used for every test: $ make run O=$PWD/kernel-$arch RUN_OUT=run.$arch.out ... > > Just rechecked the O variable in top-level Makefile, selftests/nolibc Makefile > > and tools/nolibc Makefile, all of them get the right O value from command line. > > But the one from the command line is a relative path. And it seems to be > resolved from the kernel source tree instead of from where make is > executed. > That's exactly: $ make defconfig O=out Makefile:15: objtree=out, srctree=/labs/linux-lab/src/linux-stable Makefile:114: O=/labs/linux-lab/src/linux-stable/tools/testing/selftests/nolibc/out The COMMAND_O suggested by you have prefixed $(PWD) for us, it is the right way we should apply. Seems I have passed O=something to all kernel targets before, but that is a little ugly, and when the O=$PWD/out always work for me, I even forgot to check the simpler O=out again. And it also works perfectly with $PWD: $ make defconfig O=$PWD/out Makefile:15: objtree=/labs/linux-lab/src/linux-stable/tools/testing/selftests/nolibc/out, srctree=/labs/linux-lab/src/linux-stable Makefile:114: O=/labs/linux-lab/src/linux-stable/tools/testing/selftests/nolibc/out > > From my Makefile experience, an option from command line will be passed > > to every sub Makefile via $(-*-command-variables-*-), it has the highest > > priority then the others, except when we use 'override' keyword > > internally. > > > > > the build instead is happening in $LINUX/foo. But the Makefile first > > > validates that $LINUX/tools/testing/selftests/nolibc/foo exists. > > > > > > > Sorry, I didn't get your meaning above? > > > > Do you mean this line: > > > > srctree := $(patsubst %/tools/testing/selftests/,%,$(dir $(CURDIR))) > > > > by removing tools/testing/selftests/ of curdir's dir (means no nolibc itself), > > srctree above is just the top-level kernel source code tree. > > No, srctree should be fine. > > > > It seems we need to pass $(COMMAND_O) to the recursive calls to $(MAKE), > > > too? > > > > > > > So, no need to pass O or COMMAND_O. > > As above, it doesn't work for me. > > If I add COMMAND_O to all the $(MAKE) commands that are executed > explicitly, how it is also done in Makefile.include itself, things start > to work as I would expect: > All the kernel build output is in out/ in the current directory. > Ok, let's use it. Thanks very much. After align the empty objtree value with you, will renew this patch. Best regards, Zhangjin
