From 986a506481d4edb3b5c50c8245e915e39d248c7d Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Mon, 3 Jun 2019 21:07:25 +0000 Subject: powerpc: Simplify vsyscall internal macros This patch simplifies the powerpc internal macros for vDSO calls by: - Removing INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK, used solely on get_timebase_freq. - Adjust INTERNAL_VSYSCALL_CALL_TYPE powerpc32 to follow powerpc64 argument ordering. - Use HAVE_*_VSYSCALL instead of explicit strings. - Make powerpc libc-vdso.h include generic implementation. No semantic change expected, checked on powerpc-linux-gnu-power4, powerpc64-linux-gnu, and powerpc64le-linux-gnu. * sysdeps/unix/sysv/linux/libc-vdso.h (VDSO_IFUNC_RET): Define if not defined. * sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c (__get_timebase_freq): Remove use of INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK. (get_timebase_freq_fallback): New symbol. * sysdeps/unix/sysv/linux/powerpc/gettimeofday.c (time): Use HAVE_GETTIMEOFDAY_VSYSCALL. * sysdeps/unix/sysv/linux/powerpc/time.c (gettimeofday): Use HAVE_TIME_VSYSCALL. * sysdeps/unix/sysv/linux/powerpc/libc-vdso.h: Include generic implementation. * sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h (INTERNAL_VSYSCALL_CALL_TYPE): Make calling convention similar to powerpc64. (INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK): Remove macro. * .../sysv/linux/powerpc/powerpc64/sysdep.h (INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK): Likewise. * sysdeps/unix/sysv/linux/powerpc/sysdep.h (HAVE_GETTIMEOFDAY_VSYSCALL): Define. --- sysdeps/unix/sysv/linux/libc-vdso.h | 7 +++++++ .../unix/sysv/linux/powerpc/get_timebase_freq.c | 24 ++++++++++++++-------- sysdeps/unix/sysv/linux/powerpc/libc-vdso.h | 24 ++++++++++++---------- sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h | 18 ++-------------- sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h | 19 +---------------- 5 files changed, 38 insertions(+), 54 deletions(-) (limited to 'sysdeps/unix') diff --git a/sysdeps/unix/sysv/linux/libc-vdso.h b/sysdeps/unix/sysv/linux/libc-vdso.h index 2e63aa1bba..792ac39d85 100644 --- a/sysdeps/unix/sysv/linux/libc-vdso.h +++ b/sysdeps/unix/sysv/linux/libc-vdso.h @@ -21,6 +21,13 @@ #define VDSO_SYMBOL(__name) __vdso_##__name +/* Adjust the return IFUNC value from a vDSO symbol accordingly required + by the ELFv1 ABI. It is used by the architecture to create an ODP + entry since the kernel vDSO does not provide it. */ +#ifndef VDSO_IFUNC_RET +# define VDSO_IFUNC_RET(__value) (__value) +#endif + #ifdef HAVE_CLOCK_GETTIME_VSYSCALL extern int (*VDSO_SYMBOL(clock_gettime)) (clockid_t, struct timespec *) attribute_hidden; diff --git a/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c b/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c index 7593720169..29b6624b9a 100644 --- a/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c +++ b/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c @@ -23,17 +23,11 @@ #include #include -uint64_t -__get_timebase_freq (void) +static uint64_t +get_timebase_freq_fallback (void) { hp_timing_t result = 0L; -#ifdef SHARED - /* The vDSO does not return an error (it clear cr0.so on returning). */ - INTERNAL_SYSCALL_DECL (err); - result = - INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK (get_tbfreq, err, uint64_t, 0); -#else /* We read the information from the /proc filesystem. /proc/cpuinfo contains at least one line like: timebase : 33333333 @@ -99,8 +93,20 @@ __get_timebase_freq (void) } } } -#endif return result; } + +uint64_t +__get_timebase_freq (void) +{ + /* The vDSO does not have a fallback mechanism (such calling a syscall). */ + __typeof (VDSO_SYMBOL (get_tbfreq)) vdsop = VDSO_SYMBOL (get_tbfreq); + PTR_DEMANGLE (vdsop); + if (vdsop == NULL) + return get_timebase_freq_fallback (); + + INTERNAL_SYSCALL_DECL (err); + return INTERNAL_VSYSCALL_CALL_TYPE (vdsop, err, uint64_t, 0); +} weak_alias (__get_timebase_freq, __ppc_get_timebase_freq) diff --git a/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h b/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h index 5c1f8de1c6..cb7da3b289 100644 --- a/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h +++ b/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h @@ -22,17 +22,9 @@ #include #include -#include_next - -extern unsigned long long (*VDSO_SYMBOL(get_tbfreq)) (void); -#if defined(__PPC64__) || defined(__powerpc64__) -extern void *VDSO_SYMBOL(sigtramp_rt64); -#else -extern void *VDSO_SYMBOL(sigtramp32); -extern void *VDSO_SYMBOL(sigtramp_rt32); -#endif #if (defined(__PPC64__) || defined(__powerpc64__)) && _CALL_ELF != 2 +# include /* The correct solution is for _dl_vdso_vsym to return the address of the OPD for the kernel VDSO function. That address would then be stored in the __vdso_* variables and returned as the result of the IFUNC resolver function. @@ -51,7 +43,7 @@ extern void *VDSO_SYMBOL(sigtramp_rt32); are processed immediately at startup the resolver functions and this code need not be thread-safe, but if the caller writes to a PLT slot it must do so in a thread-safe manner with all the required barriers. */ -#define VDSO_IFUNC_RET(value) \ +# define VDSO_IFUNC_RET(value) \ ({ \ static Elf64_FuncDesc vdso_opd = { .fd_toc = ~0x0 }; \ vdso_opd.fd_func = (Elf64_Addr)value; \ @@ -59,7 +51,17 @@ extern void *VDSO_SYMBOL(sigtramp_rt32); }) #else -#define VDSO_IFUNC_RET(value) ((void *) (value)) +# define VDSO_IFUNC_RET(value) ((void *) (value)) +#endif + +#include_next + +extern unsigned long long (*VDSO_SYMBOL(get_tbfreq)) (void); +#if defined(__PPC64__) || defined(__powerpc64__) +extern void *VDSO_SYMBOL(sigtramp_rt64); +#else +extern void *VDSO_SYMBOL(sigtramp32); +extern void *VDSO_SYMBOL(sigtramp_rt32); #endif #endif /* _LIBC_VDSO_H */ diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h index 1cbf1596d5..a3bb552254 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h @@ -41,7 +41,7 @@ function call, with the exception of LR (which is needed for the "sc; bnslr+" sequence) and CR (where only CR0.SO is clobbered to signal an error return status). */ -# define INTERNAL_VSYSCALL_CALL_TYPE(funcptr, err, nr, type, args...) \ +# define INTERNAL_VSYSCALL_CALL_TYPE(funcptr, err, type, nr, args...) \ ({ \ register void *r0 __asm__ ("r0"); \ register long int r3 __asm__ ("r3"); \ @@ -69,7 +69,7 @@ }) #define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...) \ - INTERNAL_VSYSCALL_CALL_TYPE(funcptr, err, nr, long int, args) + INTERNAL_VSYSCALL_CALL_TYPE(funcptr, err, long int, nr, args) # undef INLINE_SYSCALL # define INLINE_SYSCALL(name, nr, args...) \ @@ -131,20 +131,6 @@ # undef INTERNAL_SYSCALL_ERRNO # define INTERNAL_SYSCALL_ERRNO(val, err) (val) -# define INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK(name, err, type, nr, args...) \ - ({ \ - type sc_ret = ENOSYS; \ - \ - __typeof (__vdso_##name) vdsop = __vdso_##name; \ - PTR_DEMANGLE (vdsop); \ - if (vdsop != NULL) \ - sc_ret = \ - INTERNAL_VSYSCALL_CALL_TYPE (vdsop, err, nr, type, ##args); \ - else \ - err = 1 << 28; \ - sc_ret; \ - }) - # define LOADARGS_0(name, dummy) \ r0 = name # define LOADARGS_1(name, __arg1) \ diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h index fac7a9ac2e..207d9d5709 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h @@ -45,22 +45,6 @@ #endif /* __ASSEMBLER__ */ -/* This version is for internal uses when there is no desire - to set errno */ -#define INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK(name, err, type, nr, args...) \ - ({ \ - type sc_ret = ENOSYS; \ - \ - __typeof (__vdso_##name) vdsop = __vdso_##name; \ - PTR_DEMANGLE (vdsop); \ - if (vdsop != NULL) \ - sc_ret = \ - INTERNAL_VSYSCALL_CALL_TYPE (vdsop, err, type, nr, ##args); \ - else \ - err = 1 << 28; \ - sc_ret; \ - }) - /* Define a macro which expands inline into the wrapper code for a system call. This use is for internal calls that do not need to handle errors normally. It will never touch errno. This returns just what the kernel @@ -94,10 +78,9 @@ #define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...) \ INTERNAL_VSYSCALL_CALL_TYPE(funcptr, err, long int, nr, args) -#undef INLINE_SYSCALL - /* This version is for kernels that implement system calls that behave like function calls as far as register saving. */ +#undef INLINE_SYSCALL #define INLINE_SYSCALL(name, nr, args...) \ ({ \ INTERNAL_SYSCALL_DECL (sc_err); \ -- cgit 1.4.1