On 2023-06-07 19:28:58+0800, Zhangjin Wu wrote:
Willy, Thomas
This is the revision of the v2 syscall helpers [1], it is based on 20230606-nolibc-rv32+stkp7a of [2]. It doesn't conflict with the v4 of -ENOSYS patchset [3], so, it is ok to simply merge both of them.
This revision mainly applied Thomas' method, removed the __syscall() helper and replaced it with __sysret() instead, because __syscall() looks like _syscall() and syscall(), it may mixlead the developers.
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BTW, two questions for Thomas,
- This commit 659a49abc9c2 ("tools/nolibc: validate C89 compatibility") enables -std=c89, why not gnu11 used by kernel ? ;-)
Because nolibc needs to support whatever its users need. As nolibc is header-only all of it needs to work everywhere. C89 should work for everybody :-)
Get it, thanks.
The kernel on the other hand is compiled standalone and is not limited by its users.
See the discussion here:
https://lore.kernel.org/all/20230328-nolibc-c99-v2-0-c989f2289222@weissschuh... https://lore.kernel.org/all/20230328-nolibc-c99-v1-1-a8302fb19f19@weissschuh...
Thanks very much for sharing the whole history info.
And as the your commit 063b6bc5b39f ("tools/nolibc: use __inline__ syntax") explains, the 'inline' keyword has been used in many headers of include/uapi/, so, how our -std=c89 work with them? I did find the clue eventually, here maybe:
$ grep -n inline scripts/headers_install.sh 11: echo "asm/inline/volatile keywords." 37: s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
The headers_install target helped us convert all of the new keywords to the old ones, it's magic ;-)
So, it should work if people not want to try a -I/path/to/include/uapi/, I did this for musl before, even If we do this, this may help:
diff --git a/tools/include/nolibc/std.h b/tools/include/nolibc/std.h index 933bc0be7e1c..33d546cf9af0 100644 --- a/tools/include/nolibc/std.h +++ b/tools/include/nolibc/std.h @@ -7,6 +7,14 @@ #ifndef _NOLIBC_STD_H #define _NOLIBC_STD_H
+#ifndef NOLIBC_TEST +#ifndef __STDC_VERSION__ +#define inline __inline__ +#define asm __asm__ +#define volatile __volatile__ +#endif +#endif + /* Declare a few quite common macros and types that usually are in stdlib.h, * stdint.h, ctype.h, unistd.h and a few other common locations. Please place * integer type definitions and generic macros here, but avoid OS-specific and diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile index 4a3a105e1fdf..46f061a4458a 100644 --- a/tools/testing/selftests/nolibc/Makefile +++ b/tools/testing/selftests/nolibc/Makefile @@ -78,7 +78,7 @@ endif
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 \ +CFLAGS ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -DNOLIBC_TEST \ $(call cc-option,-fno-stack-protector) \ $(CFLAGS_$(ARCH)) $(CFLAGS_STACKPROTECTOR)
Is this worth a new patch? I do think it is not required.
Do we need to tune the order of the macros in unistd.h like this:
#define _syscall(N, ...) __sysret(my_syscall##N(__VA_ARGS__)) #define _syscall_n(N, ...) _syscall(N, __VA_ARGS__) #define __syscall_narg(_0, _1, _2, _3, _4, _5, _6, N, ...) N #define _sycall_narg(...) __syscall_narg(__VA_ARGS__, 6, 5, 4, 3, 2, 1, 0) #define syscall(...) _syscall_n(_sycall_narg(__VA_ARGS__), ##__VA_ARGS__)
Before, It works but seems not put in using order:
#define _syscall(N, ...) __sysret(my_syscall##N(__VA_ARGS__)) #define _sycall_narg(...) __syscall_narg(__VA_ARGS__, 6, 5, 4, 3, 2, 1, 0) #define __syscall_narg(_0, _1, _2, _3, _4, _5, _6, N, ...) N #define _syscall_n(N, ...) _syscall(N, __VA_ARGS__) #define syscall(...) _syscall_n(_sycall_narg(__VA_ARGS__), ##__VA_ARGS__)
Not sure it makes a big difference. If you want to change it, go for it.
Only switched two of them, oh, just found the '_sycall_narg' did miss a 's' character, it may be really worth a patch now, I know why I focused on the order so much, because the missing 's' made it not aligned well ;-)
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tools/include/nolibc/sys.h | 364 +++++----------------------------- tools/include/nolibc/unistd.h | 11 +- 2 files changed, 55 insertions(+), 320 deletions(-)
For the full series:
Reviewed-by: Thomas Weißschuh linux@weissschuh.net
Thanks a lot, I'm really appreciated.
Best regards, Zhangjin
Thanks, Thomas