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@1wt.eu Link: https://lore.kernel.org/lkml/ZK0AB1OXH1s2xYsh@1wt.eu/ Signed-off-by: Zhangjin Wu falcon@tinylab.org
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