Hi, Willy
This is the v4 part2 of support for rv32 (v3 [1]), it applied the suggestions from Thomas, Arnd [2] and you [3]. now, the rv32 compile support almost aligned with x86 except the extra KARCH to make kernel happy, thanks very much for your nice review!
Since the 'override' method mentioned in [4] split the whole Makefile context to two parts, it may make the code not that easy to maintain, so, this patchset goes back to the KARCH (suggested from Willy, before, I used something like _ARCH) passing method, as suggested by Willy, we also aligned the KARCH assignment with the other variables.
Changes from v3 -> v4:
* No new changes in the first two except a new Reviewed-by line from Arnd
* selftests/nolibc: riscv: customize makefile for rv32
Do it like the other architectures, especially like x86.
The difference from x86 is, the top-level kernel Makefile doesn't accept riscv32 and riscv64, it only accept riscv, to make kernel happy, a KARCH variable is added for riscv32 and riscv64, and then passed to kernel with ARCH=$(KARCH).
Since tools/include/nolibc/Makefile shares arch-riscv.h between riscv32 and riscv64 and there is a headers_standalone target who called kernel headers and headers_install, so, pass ARCH=$(KARCH) to it too.
Did compile test for aarch64, rv32 and rv64, include run-user and run.
Note, this is required with the default config from the 20230606-nolibc-rv32+stkp7a branch of [5]:
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index ce02bb09651b..72bd8fe0cad6 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1934,11 +1934,13 @@ void show_rcu_tasks_gp_kthreads(void) } #endif /* #ifndef CONFIG_TINY_RCU */
+#ifdef CONFIG_TASKS_RCU struct task_struct *get_rcu_tasks_gp_kthread(void) { return rcu_tasks.kthread_ptr; } EXPORT_SYMBOL_GPL(get_rcu_tasks_gp_kthread); +#endif
#ifdef CONFIG_PROVE_RCU struct rcu_tasks_test_desc {
Best regards, Zhangjin
---
[1]: https://lore.kernel.org/linux-riscv/cover.1685780412.git.falcon@tinylab.org/ [2]: https://lore.kernel.org/linux-riscv/d1c83340-af4c-4780-a101-b9d22b47379c@app... [3]: https://lore.kernel.org/lkml/ZIAywHvr6UB1J4of@1wt.eu/ [4]: https://lore.kernel.org/lkml/20230607063314.671429-1-falcon@tinylab.org/ [5]: https://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/nolibc.git
Zhangjin Wu (3): tools/nolibc: fix up #error compile failures with -ENOSYS tools/nolibc: fix up undeclared syscall macros with #ifdef and -ENOSYS selftests/nolibc: riscv: customize makefile for rv32
tools/include/nolibc/sys.h | 38 ++++++++++++++++--------- tools/testing/selftests/nolibc/Makefile | 20 +++++++++++-- 2 files changed, 42 insertions(+), 16 deletions(-)
Compiling nolibc for rv32 got such errors:
In file included from nolibc/sysroot/riscv/include/nolibc.h:99, from nolibc/sysroot/riscv/include/errno.h:26, from nolibc/sysroot/riscv/include/stdio.h:14, from tools/testing/selftests/nolibc/nolibc-test.c:12: nolibc/sysroot/riscv/include/sys.h:946:2: error: #error Neither __NR_ppoll nor __NR_poll defined, cannot implement sys_poll() 946 | #error Neither __NR_ppoll nor __NR_poll defined, cannot implement sys_poll() | ^~~~~ nolibc/sysroot/riscv/include/sys.h:1062:2: error: #error None of __NR_select, __NR_pselect6, nor __NR__newselect defined, cannot implement sys_select() 1062 | #error None of __NR_select, __NR_pselect6, nor __NR__newselect defined, cannot implement sys_select()
If a syscall is not supported by a target platform, 'return -ENOSYS' is better than '#error', which lets the other syscalls work as-is and allows developers to fix up the test failures reported by nolibc-test one by one later.
This converts all of the '#error' to 'return -ENOSYS', so, all of the '#error' failures are fixed.
Suggested-by: Arnd Bergmann arnd@arndb.de Link: https://lore.kernel.org/linux-riscv/5e7d2adf-e96f-41ca-a4c6-5c87a25d4c9c@app... Reviewed-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Zhangjin Wu falcon@tinylab.org --- tools/include/nolibc/sys.h | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index 856249a11890..78c86f124335 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -124,7 +124,7 @@ int sys_chmod(const char *path, mode_t mode) #elif defined(__NR_chmod) return my_syscall2(__NR_chmod, path, mode); #else -#error Neither __NR_fchmodat nor __NR_chmod defined, cannot implement sys_chmod() + return -ENOSYS; #endif }
@@ -153,7 +153,7 @@ int sys_chown(const char *path, uid_t owner, gid_t group) #elif defined(__NR_chown) return my_syscall3(__NR_chown, path, owner, group); #else -#error Neither __NR_fchownat nor __NR_chown defined, cannot implement sys_chown() + return -ENOSYS; #endif }
@@ -251,7 +251,7 @@ int sys_dup2(int old, int new) #elif defined(__NR_dup2) return my_syscall2(__NR_dup2, old, new); #else -#error Neither __NR_dup3 nor __NR_dup2 defined, cannot implement sys_dup2() + return -ENOSYS; #endif }
@@ -351,7 +351,7 @@ pid_t sys_fork(void) #elif defined(__NR_fork) return my_syscall0(__NR_fork); #else -#error Neither __NR_clone nor __NR_fork defined, cannot implement sys_fork() + return -ENOSYS; #endif } #endif @@ -648,7 +648,7 @@ int sys_link(const char *old, const char *new) #elif defined(__NR_link) return my_syscall2(__NR_link, old, new); #else -#error Neither __NR_linkat nor __NR_link defined, cannot implement sys_link() + return -ENOSYS; #endif }
@@ -700,7 +700,7 @@ int sys_mkdir(const char *path, mode_t mode) #elif defined(__NR_mkdir) return my_syscall2(__NR_mkdir, path, mode); #else -#error Neither __NR_mkdirat nor __NR_mkdir defined, cannot implement sys_mkdir() + return -ENOSYS; #endif }
@@ -729,7 +729,7 @@ long sys_mknod(const char *path, mode_t mode, dev_t dev) #elif defined(__NR_mknod) return my_syscall3(__NR_mknod, path, mode, dev); #else -#error Neither __NR_mknodat nor __NR_mknod defined, cannot implement sys_mknod() + return -ENOSYS; #endif }
@@ -848,7 +848,7 @@ int sys_open(const char *path, int flags, mode_t mode) #elif defined(__NR_open) return my_syscall3(__NR_open, path, flags, mode); #else -#error Neither __NR_openat nor __NR_open defined, cannot implement sys_open() + return -ENOSYS; #endif }
@@ -943,7 +943,7 @@ int sys_poll(struct pollfd *fds, int nfds, int timeout) #elif defined(__NR_poll) return my_syscall3(__NR_poll, fds, nfds, timeout); #else -#error Neither __NR_ppoll nor __NR_poll defined, cannot implement sys_poll() + return -ENOSYS; #endif }
@@ -1059,7 +1059,7 @@ int sys_select(int nfds, fd_set *rfds, fd_set *wfds, fd_set *efds, struct timeva #endif return my_syscall5(__NR__newselect, nfds, rfds, wfds, efds, timeout); #else -#error None of __NR_select, __NR_pselect6, nor __NR__newselect defined, cannot implement sys_select() + return -ENOSYS; #endif }
@@ -1196,7 +1196,7 @@ int sys_stat(const char *path, struct stat *buf) #elif defined(__NR_stat) ret = my_syscall2(__NR_stat, path, &stat); #else -#error Neither __NR_newfstatat nor __NR_stat defined, cannot implement sys_stat() + return -ENOSYS; #endif buf->st_dev = stat.st_dev; buf->st_ino = stat.st_ino; @@ -1243,7 +1243,7 @@ int sys_symlink(const char *old, const char *new) #elif defined(__NR_symlink) return my_syscall2(__NR_symlink, old, new); #else -#error Neither __NR_symlinkat nor __NR_symlink defined, cannot implement sys_symlink() + return -ENOSYS; #endif }
@@ -1312,7 +1312,7 @@ int sys_unlink(const char *path) #elif defined(__NR_unlink) return my_syscall1(__NR_unlink, path); #else -#error Neither __NR_unlinkat nor __NR_unlink defined, cannot implement sys_unlink() + return -ENOSYS; #endif }
Compiling nolibc for rv32 got such errors:
nolibc/sysroot/riscv/include/sys.h: In function ‘sys_gettimeofday’: nolibc/sysroot/riscv/include/sys.h:557:21: error: ‘__NR_gettimeofday’ undeclared (first use in this function); did you mean ‘sys_gettimeofday’? 557 | return my_syscall2(__NR_gettimeofday, tv, tz); | ^~~~~~~~~~~~~~~~~ nolibc/sysroot/riscv/include/sys.h: In function ‘sys_lseek’: nolibc/sysroot/riscv/include/sys.h:675:21: error: ‘__NR_lseek’ undeclared (first use in this function) 675 | return my_syscall3(__NR_lseek, fd, offset, whence); | ^~~~~~~~~~ nolibc/sysroot/riscv/include/sys.h: In function ‘sys_wait4’: nolibc/sysroot/riscv/include/sys.h:1341:21: error: ‘__NR_wait4’ undeclared (first use in this function) 1341 | return my_syscall4(__NR_wait4, pid, status, options, rusage);
If a syscall macro is not supported by a target platform, wrap it with '#ifdef' and 'return -ENOSYS' for the '#else' branch, which lets the other syscalls work as-is and allows developers to fix up the test failures reported by nolibc-test one by one later.
This wraps all of the failed syscall macros with '#ifdef' and 'return -ENOSYS' for the '#else' branch, so, all of the undeclared failures are fixed.
Suggested-by: Arnd Bergmann arnd@arndb.de Link: https://lore.kernel.org/linux-riscv/5e7d2adf-e96f-41ca-a4c6-5c87a25d4c9c@app... Reviewed-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Zhangjin Wu falcon@tinylab.org --- tools/include/nolibc/sys.h | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h index 78c86f124335..5464f93e863e 100644 --- a/tools/include/nolibc/sys.h +++ b/tools/include/nolibc/sys.h @@ -554,7 +554,11 @@ long getpagesize(void) static __attribute__((unused)) int sys_gettimeofday(struct timeval *tv, struct timezone *tz) { +#ifdef __NR_gettimeofday return my_syscall2(__NR_gettimeofday, tv, tz); +#else + return -ENOSYS; +#endif }
static __attribute__((unused)) @@ -672,7 +676,11 @@ int link(const char *old, const char *new) static __attribute__((unused)) off_t sys_lseek(int fd, off_t offset, int whence) { +#ifdef __NR_lseek return my_syscall3(__NR_lseek, fd, offset, whence); +#else + return -ENOSYS; +#endif }
static __attribute__((unused)) @@ -1338,7 +1346,11 @@ int unlink(const char *path) static __attribute__((unused)) pid_t sys_wait4(pid_t pid, int *status, int options, struct rusage *rusage) { +#ifdef __NR_wait4 return my_syscall4(__NR_wait4, pid, status, options, rusage); +#else + return -ENOSYS; +#endif }
static __attribute__((unused))
Both riscv64 and riscv32 have:
* the same arch/riscv source code tree * the same tools/include/nolibc/arch-riscv.h * the same ARCH=riscv value passed to top-level kernel Makefile
The only differences are:
* riscv64 uses defconfig, riscv32 uses rv32_defconfig * riscv64 uses qemu-system-riscv64, riscv32 uses qemu-system-riscv32 * riscv32 has different compiler options (-march= and -mabi=)
So, riscv32 can share most of the settings with riscv64, add riscv32 support like the original ARCH=riscv support.
To align with x86, the default riscv is reserved for riscv64 and a new riscv64 is also added to allow users pass ARCH=riscv64 directly.
Since top-level kernel Makefile only accept ARCH=riscv, to make it happy, let's add a KARCH, set it as riscv for riscv32 and riscv64, and set it as original ARCH for the others, at last pass it to kernel targets with ARCH=$(KARCH).
The same ARCH=$(KARCH) passed to tools/include/nolibc/Makefile, for both arch-riscv.h and the headers_standalone target require it too.
Usage:
$ make defconfig ARCH=riscv32 CROSS_COMPILE=riscv64-linux-gnu- ... $ make run ARCH=riscv32 CROSS_COMPILE=riscv64-linux-gnu- ...
Suggested-by: Thomas Weißschuh linux@weissschuh.net Link: https://lore.kernel.org/linux-riscv/4a3b1cdf-91d5-4668-925e-21f8f5c64a92@t-8... Suggested-by: Arnd Bergmann arnd@arndb.de Link: https://lore.kernel.org/linux-riscv/d1c83340-af4c-4780-a101-b9d22b47379c@app... Suggested-by: Willy Tarreau w@1wt.eu Link: https://lore.kernel.org/lkml/ZIAywHvr6UB1J4of@1wt.eu/ Signed-off-by: Zhangjin Wu falcon@tinylab.org --- tools/testing/selftests/nolibc/Makefile | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile index 4a3a105e1fdf..48fa22817d90 100644 --- a/tools/testing/selftests/nolibc/Makefile +++ b/tools/testing/selftests/nolibc/Makefile @@ -14,6 +14,11 @@ include $(srctree)/scripts/subarch.include ARCH = $(SUBARCH) endif
+# kernel supported ARCH names by architecture +KARCH_riscv32 = riscv +KARCH_riscv64 = riscv +KARCH = $(or $(KARCH_$(ARCH)),$(ARCH)) + # kernel image names by architecture IMAGE_i386 = arch/x86/boot/bzImage IMAGE_x86_64 = arch/x86/boot/bzImage @@ -21,6 +26,8 @@ IMAGE_x86 = arch/x86/boot/bzImage IMAGE_arm64 = arch/arm64/boot/Image IMAGE_arm = arch/arm/boot/zImage IMAGE_mips = vmlinuz +IMAGE_riscv32 = arch/riscv/boot/Image +IMAGE_riscv64 = arch/riscv/boot/Image IMAGE_riscv = arch/riscv/boot/Image IMAGE_s390 = arch/s390/boot/bzImage IMAGE_loongarch = arch/loongarch/boot/vmlinuz.efi @@ -34,6 +41,8 @@ DEFCONFIG_x86 = defconfig DEFCONFIG_arm64 = defconfig DEFCONFIG_arm = multi_v7_defconfig DEFCONFIG_mips = malta_defconfig +DEFCONFIG_riscv32 = rv32_defconfig +DEFCONFIG_riscv64 = defconfig DEFCONFIG_riscv = defconfig DEFCONFIG_s390 = defconfig DEFCONFIG_loongarch = defconfig @@ -49,6 +58,8 @@ QEMU_ARCH_x86 = x86_64 QEMU_ARCH_arm64 = aarch64 QEMU_ARCH_arm = arm QEMU_ARCH_mips = mipsel # works with malta_defconfig +QEMU_ARCH_riscv32 = riscv32 +QEMU_ARCH_riscv64 = riscv64 QEMU_ARCH_riscv = riscv64 QEMU_ARCH_s390 = s390x QEMU_ARCH_loongarch = loongarch64 @@ -61,6 +72,8 @@ QEMU_ARGS_x86 = -M pc -append "console=ttyS0,9600 i8042.noaux panic=-1 $( QEMU_ARGS_arm64 = -M virt -cpu cortex-a53 -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)" QEMU_ARGS_arm = -M virt -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)" QEMU_ARGS_mips = -M malta -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)" +QEMU_ARGS_riscv32 = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)" +QEMU_ARGS_riscv64 = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)" QEMU_ARGS_riscv = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)" QEMU_ARGS_s390 = -M s390-ccw-virtio -m 1G -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)" QEMU_ARGS_loongarch = -M virt -append "console=ttyS0,115200 panic=-1 $(TEST:%=NOLIBC_TEST=%)" @@ -76,6 +89,7 @@ else Q=@ endif
+CFLAGS_riscv32 = -march=rv32im -mabi=ilp32 CFLAGS_s390 = -m64 CFLAGS_STACKPROTECTOR ?= $(call cc-option,-mstack-protector-guard=global $(call cc-option,-fstack-protector-all)) CFLAGS ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \ @@ -117,7 +131,7 @@ sysroot: sysroot/$(ARCH)/include sysroot/$(ARCH)/include: $(Q)rm -rf sysroot/$(ARCH) sysroot/sysroot $(QUIET_MKDIR)mkdir -p sysroot - $(Q)$(MAKE) -C ../../../include/nolibc ARCH=$(ARCH) OUTPUT=$(CURDIR)/sysroot/ headers_standalone + $(Q)$(MAKE) -C ../../../include/nolibc ARCH=$(KARCH) OUTPUT=$(CURDIR)/sysroot/ headers_standalone $(Q)mv sysroot/sysroot sysroot/$(ARCH)
nolibc-test: nolibc-test.c sysroot/$(ARCH)/include @@ -141,10 +155,10 @@ initramfs: nolibc-test $(Q)cp nolibc-test initramfs/init
defconfig: - $(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) mrproper $(DEFCONFIG) prepare + $(Q)$(MAKE) -C $(srctree) ARCH=$(KARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) mrproper $(DEFCONFIG) prepare
kernel: initramfs - $(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(IMAGE_NAME) CONFIG_INITRAMFS_SOURCE=$(CURDIR)/initramfs + $(Q)$(MAKE) -C $(srctree) ARCH=$(KARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(IMAGE_NAME) CONFIG_INITRAMFS_SOURCE=$(CURDIR)/initramfs
# run the tests after building the kernel run: kernel
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