mirror of
git://git.musl-libc.org/musl
synced 2025-01-09 16:19:50 +00:00
4486c579cb
it's been reported that the vdso clock_gettime64 function on (32-bit) arm is broken, producing erratic results that grow at a rate far greater than one reported second per actual elapsed second. the vdso function seems to have been added sometime between linux 5.4 and 5.6, so if there's ever been a working version, it was only present for a very short window. it's not clear what the eventual upstream kernel solution will be, but something needs to be done on the libc side so as not to be producing binaries that seem to work on older/existing/lts kernels (which lack the function and thus lack the bug) but will break fantastically when moving to newer kernels. hopefully vdso support will be added back soon, but with a new symbol name or version from the kernel to allow continued rejection of broken ones.
104 lines
3.0 KiB
C
104 lines
3.0 KiB
C
#define __SYSCALL_LL_E(x) \
|
|
((union { long long ll; long l[2]; }){ .ll = x }).l[0], \
|
|
((union { long long ll; long l[2]; }){ .ll = x }).l[1]
|
|
#define __SYSCALL_LL_O(x) 0, __SYSCALL_LL_E((x))
|
|
|
|
#ifdef __thumb__
|
|
|
|
/* Avoid use of r7 in asm constraints when producing thumb code,
|
|
* since it's reserved as frame pointer and might not be supported. */
|
|
#define __ASM____R7__
|
|
#define __asm_syscall(...) do { \
|
|
__asm__ __volatile__ ( "mov %1,r7 ; mov r7,%2 ; svc 0 ; mov r7,%1" \
|
|
: "=r"(r0), "=&r"((int){0}) : __VA_ARGS__ : "memory"); \
|
|
return r0; \
|
|
} while (0)
|
|
|
|
#else
|
|
|
|
#define __ASM____R7__ __asm__("r7")
|
|
#define __asm_syscall(...) do { \
|
|
__asm__ __volatile__ ( "svc 0" \
|
|
: "=r"(r0) : __VA_ARGS__ : "memory"); \
|
|
return r0; \
|
|
} while (0)
|
|
#endif
|
|
|
|
/* For thumb2, we can allow 8-bit immediate syscall numbers, saving a
|
|
* register in the above dance around r7. Does not work for thumb1 where
|
|
* only movs, not mov, supports immediates, and we can't use movs because
|
|
* it doesn't support high regs. */
|
|
#ifdef __thumb2__
|
|
#define R7_OPERAND "rI"(r7)
|
|
#else
|
|
#define R7_OPERAND "r"(r7)
|
|
#endif
|
|
|
|
static inline long __syscall0(long n)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0");
|
|
__asm_syscall(R7_OPERAND);
|
|
}
|
|
|
|
static inline long __syscall1(long n, long a)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0") = a;
|
|
__asm_syscall(R7_OPERAND, "0"(r0));
|
|
}
|
|
|
|
static inline long __syscall2(long n, long a, long b)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0") = a;
|
|
register long r1 __asm__("r1") = b;
|
|
__asm_syscall(R7_OPERAND, "0"(r0), "r"(r1));
|
|
}
|
|
|
|
static inline long __syscall3(long n, long a, long b, long c)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0") = a;
|
|
register long r1 __asm__("r1") = b;
|
|
register long r2 __asm__("r2") = c;
|
|
__asm_syscall(R7_OPERAND, "0"(r0), "r"(r1), "r"(r2));
|
|
}
|
|
|
|
static inline long __syscall4(long n, long a, long b, long c, long d)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0") = a;
|
|
register long r1 __asm__("r1") = b;
|
|
register long r2 __asm__("r2") = c;
|
|
register long r3 __asm__("r3") = d;
|
|
__asm_syscall(R7_OPERAND, "0"(r0), "r"(r1), "r"(r2), "r"(r3));
|
|
}
|
|
|
|
static inline long __syscall5(long n, long a, long b, long c, long d, long e)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0") = a;
|
|
register long r1 __asm__("r1") = b;
|
|
register long r2 __asm__("r2") = c;
|
|
register long r3 __asm__("r3") = d;
|
|
register long r4 __asm__("r4") = e;
|
|
__asm_syscall(R7_OPERAND, "0"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4));
|
|
}
|
|
|
|
static inline long __syscall6(long n, long a, long b, long c, long d, long e, long f)
|
|
{
|
|
register long r7 __ASM____R7__ = n;
|
|
register long r0 __asm__("r0") = a;
|
|
register long r1 __asm__("r1") = b;
|
|
register long r2 __asm__("r2") = c;
|
|
register long r3 __asm__("r3") = d;
|
|
register long r4 __asm__("r4") = e;
|
|
register long r5 __asm__("r5") = f;
|
|
__asm_syscall(R7_OPERAND, "0"(r0), "r"(r1), "r"(r2), "r"(r3), "r"(r4), "r"(r5));
|
|
}
|
|
|
|
#define SYSCALL_FADVISE_6_ARG
|
|
|
|
#define SYSCALL_IPC_BROKEN_MODE
|