On Sun, Sep 17, 2023 at 05:21:38PM +0200 Thomas Weißschuh wrote: > When the initramfs is embedded into the kernel each rebuild of it will > trigger a full kernel relink and all the expensive postprocessing steps. > > Currently nolibc-test and therefore the initramfs are always rebuild, > even without source changes, leading to lots of slow kernel relinks. > > Instead of linking the initramfs into the kernel assemble it manually > and pass it explicitly to qemu. > This avoids all of the kernel relinks. > > Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> > --- > Currently the nolibc testsuite embeds the test executable into a kernel > image with CONFIG_INITRAMFS_SOURCE. > This forces a full kernel relink everytime the test executable is > updated. > > This relinking step dominates the test cycle. > It is slower than building and running the test in qemu together. > > With a bit of Makefile-shuffling the relinking can be avoided. > --- > Changes in v2: > - avoid need to modify top-level Makefile > - drop patch removing "rerun" target > - add kernel-standalone target > - Link to v1: https://lore.kernel.org/r/20230916-nolibc-initramfs-v1-0-4416ecedca6d@xxxxxxxxxxxxxx > --- Thanks, seems to work as described (and I am surprised how fast the 'run' target is) and patch looks good to me. Reviewed-by: Nicolas Schier <nicolas@xxxxxxxxx> > tools/testing/selftests/nolibc/Makefile | 42 ++++++++++++++++++++------------- > 1 file changed, 26 insertions(+), 16 deletions(-) > > diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile > index 689658f81a19..ee6a9ad28cfd 100644 > --- a/tools/testing/selftests/nolibc/Makefile > +++ b/tools/testing/selftests/nolibc/Makefile > @@ -131,18 +131,20 @@ REPORT ?= awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{if (!f) printf("\n"); f++ > > help: > @echo "Supported targets under selftests/nolibc:" > - @echo " all call the \"run\" target below" > - @echo " help this help" > - @echo " sysroot create the nolibc sysroot here (uses \$$ARCH)" > - @echo " nolibc-test build the executable (uses \$$CC and \$$CROSS_COMPILE)" > - @echo " libc-test build an executable using the compiler's default libc instead" > - @echo " run-user runs the executable under QEMU (uses \$$XARCH, \$$TEST)" > - @echo " initramfs prepare the initramfs with nolibc-test" > - @echo " defconfig create a fresh new default config (uses \$$XARCH)" > - @echo " kernel (re)build the kernel with the initramfs (uses \$$XARCH)" > - @echo " run runs the kernel in QEMU after building it (uses \$$XARCH, \$$TEST)" > - @echo " rerun runs a previously prebuilt kernel in QEMU (uses \$$XARCH, \$$TEST)" > - @echo " clean clean the sysroot, initramfs, build and output files" > + @echo " all call the \"run\" target below" > + @echo " help this help" > + @echo " sysroot create the nolibc sysroot here (uses \$$ARCH)" > + @echo " nolibc-test build the executable (uses \$$CC and \$$CROSS_COMPILE)" > + @echo " libc-test build an executable using the compiler's default libc instead" > + @echo " run-user runs the executable under QEMU (uses \$$XARCH, \$$TEST)" > + @echo " initramfs.cpio prepare the initramfs archive with nolibc-test" > + @echo " initramfs prepare the initramfs tree with nolibc-test" > + @echo " defconfig create a fresh new default config (uses \$$XARCH)" > + @echo " kernel (re)build the kernel (uses \$$XARCH)" > + @echo " kernel-standalone (re)build the kernel with the initramfs (uses \$$XARCH)" > + @echo " run runs the kernel in QEMU after building it (uses \$$XARCH, \$$TEST)" > + @echo " rerun runs a previously prebuilt kernel in QEMU (uses \$$XARCH, \$$TEST)" > + @echo " clean clean the sysroot, initramfs, build and output files" > @echo "" > @echo "The output file is \"run.out\". Test ranges may be passed using \$$TEST." > @echo "" > @@ -195,6 +197,9 @@ run-user: nolibc-test > $(Q)qemu-$(QEMU_ARCH) ./nolibc-test > "$(CURDIR)/run.out" || : > $(Q)$(REPORT) $(CURDIR)/run.out > > +initramfs.cpio: kernel nolibc-test > + $(QUIET_GEN)echo 'file /init nolibc-test 755 0 0' | $(srctree)/usr/gen_init_cpio - > initramfs.cpio > + > initramfs: nolibc-test > $(QUIET_MKDIR)mkdir -p initramfs > $(call QUIET_INSTALL, initramfs/init) > @@ -203,17 +208,20 @@ initramfs: nolibc-test > defconfig: > $(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) mrproper $(DEFCONFIG) prepare > > -kernel: initramfs > +kernel: > + $(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(IMAGE_NAME) > + > +kernel-standalone: initramfs > $(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(IMAGE_NAME) CONFIG_INITRAMFS_SOURCE=$(CURDIR)/initramfs > > # run the tests after building the kernel > -run: kernel > - $(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(srctree)/$(IMAGE)" -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out" > +run: kernel initramfs.cpio > + $(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(srctree)/$(IMAGE)" -initrd initramfs.cpio -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out" > $(Q)$(REPORT) $(CURDIR)/run.out > > # re-run the tests from an existing kernel > rerun: > - $(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(srctree)/$(IMAGE)" -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out" > + $(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(srctree)/$(IMAGE)" -initrd initramfs.cpio -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out" > $(Q)$(REPORT) $(CURDIR)/run.out > > # report with existing test log > @@ -227,6 +235,8 @@ clean: > $(Q)rm -f nolibc-test > $(call QUIET_CLEAN, libc-test) > $(Q)rm -f libc-test > + $(call QUIET_CLEAN, initramfs.cpio) > + $(Q)rm -rf initramfs.cpio > $(call QUIET_CLEAN, initramfs) > $(Q)rm -rf initramfs > $(call QUIET_CLEAN, run.out) > > --- > base-commit: 3f79a57865b33f49fdae6655510bd27c8e6610e0 > change-id: 20230916-nolibc-initramfs-4fd00eac3256 > > Best regards, > -- > Thomas Weißschuh <linux@xxxxxxxxxxxxxx> -- epost|xmpp: nicolas@xxxxxxxxx irc://oftc.net/nsc ↳ gpg: 18ed 52db e34f 860e e9fb c82b 7d97 0932 55a0 ce7f -- frykten for herren er opphav til kunnskap --
