From a4d7fe35cd8f860b1cdf3521834a666447aba4c8 Mon Sep 17 00:00:00 2001 From: Stefan Liebler Date: Fri, 7 Oct 2016 09:56:47 +0200 Subject: ppc: Use libc_ifunc macro for time, gettimeofday. This patch uses the libc_ifunc_hidden macro to create already existing ifunc functions time and gettimeofday on power. This way, the libc_hidden_def macro can be used instead of inline assemblies. On ppc32, the __GI_* symbols do not target the ifunc symbol and thus the redirection construct has to be applied here. ChangeLog: * sysdeps/unix/sysv/linux/powerpc/gettimeofday.c (__gettimeofday): Use libc_ifunc_hidden and libc_hidden_def macro. Redirect ifunced function in header for using it as type for ifunc function because __GI_* symbols for ppc32 do not target the ifunc symbols. * sysdeps/unix/sysv/linux/powerpc/time.c (time): Likewise. --- ChangeLog | 8 +++ sysdeps/unix/sysv/linux/powerpc/gettimeofday.c | 60 ++++++++++++----------- sysdeps/unix/sysv/linux/powerpc/time.c | 67 +++++++++++++------------- 3 files changed, 73 insertions(+), 62 deletions(-) diff --git a/ChangeLog b/ChangeLog index 1378071b1f..4cf22340f9 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2016-10-07 Stefan Liebler + + * sysdeps/unix/sysv/linux/powerpc/gettimeofday.c (__gettimeofday): + Use libc_ifunc_hidden and libc_hidden_def macro. Redirect ifunced function + in header for using it as type for ifunc function because __GI_* symbols + for ppc32 do not target the ifunc symbols. + * sysdeps/unix/sysv/linux/powerpc/time.c (time): Likewise. + 2016-10-07 Stefan Liebler * sysdeps/unix/sysv/linux/x86/gettimeofday.c (__gettimeofday): diff --git a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c index 25a4e7caff..16c00d7aee 100644 --- a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c +++ b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c @@ -15,6 +15,11 @@ License along with the GNU C Library; if not, see . */ +#if defined SHARED && !defined __powerpc64__ +# define __gettimeofday __redirect___gettimeofday +#else +# define __redirect___gettimeofday __gettimeofday +#endif #include @@ -24,30 +29,14 @@ # include # include -void *gettimeofday_ifunc (void) __asm__ ("__gettimeofday"); - -static int -__gettimeofday_syscall (struct timeval *tv, struct timezone *tz) -{ - return INLINE_SYSCALL (gettimeofday, 2, tv, tz); -} +# ifndef __powerpc64__ +# undef __gettimeofday -void * -gettimeofday_ifunc (void) +int +__gettimeofday_vsyscall (struct timeval *tv, struct timezone *tz) { - PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565); - - /* If the vDSO is not available we fall back syscall. */ - void *vdso_gettimeofday = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615); - return (vdso_gettimeofday ? VDSO_IFUNC_RET (vdso_gettimeofday) - : (void*)__gettimeofday_syscall); + return INLINE_VSYSCALL (gettimeofday, 2, tv, tz); } -asm (".type __gettimeofday, %gnu_indirect_function"); - -/* This is doing "libc_hidden_def (__gettimeofday)" but the compiler won't - let us do it in C because it doesn't know we're defining __gettimeofday - here in this file. */ -asm (".globl __GI___gettimeofday"); /* __GI___gettimeofday is defined as hidden and for ppc32 it enables the compiler make a local call (symbol@local) for internal GLIBC usage. It @@ -55,16 +44,29 @@ asm (".globl __GI___gettimeofday"); For ppc64 a call to a function in another translation unit might use a different toc pointer thus disallowing direct branchess and making internal ifuncs calls safe. */ -#ifdef __powerpc64__ -asm ("__GI___gettimeofday = __gettimeofday"); -#else -int -__gettimeofday_vsyscall (struct timeval *tv, struct timezone *tz) +# undef libc_hidden_def +# define libc_hidden_def(name) \ + __hidden_ver1 (__gettimeofday_vsyscall, __GI___gettimeofday, \ + __gettimeofday_vsyscall); + +# endif /* !__powerpc64__ */ + +static int +__gettimeofday_syscall (struct timeval *tv, struct timezone *tz) { - return INLINE_VSYSCALL (gettimeofday, 2, tv, tz); + return INLINE_SYSCALL (gettimeofday, 2, tv, tz); } -asm ("__GI___gettimeofday = __gettimeofday_vsyscall"); -#endif + +# define INIT_ARCH() \ + PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565); \ + void *vdso_gettimeofday = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615); + +/* If the vDSO is not available we fall back syscall. */ +libc_ifunc_hidden (__redirect___gettimeofday, __gettimeofday, + vdso_gettimeofday + ? VDSO_IFUNC_RET (vdso_gettimeofday) + : (void *) __gettimeofday_syscall); +libc_hidden_def (__gettimeofday) #else diff --git a/sysdeps/unix/sysv/linux/powerpc/time.c b/sysdeps/unix/sysv/linux/powerpc/time.c index 797341944c..3da0b66dac 100644 --- a/sysdeps/unix/sysv/linux/powerpc/time.c +++ b/sysdeps/unix/sysv/linux/powerpc/time.c @@ -17,6 +17,11 @@ . */ #ifdef SHARED +# ifndef __powerpc64__ +# define time __redirect_time +# else +# define __redirect_time time +# endif # include # include @@ -24,7 +29,26 @@ # include # include -void *time_ifunc (void) asm ("time"); +# ifndef __powerpc64__ +# undef time + +time_t +__time_vsyscall (time_t *t) +{ + return INLINE_VSYSCALL (time, 1, t); +} + +/* __GI_time is defined as hidden and for ppc32 it enables the + compiler make a local call (symbol@local) for internal GLIBC usage. It + means the PLT won't be used and the ifunc resolver will be called directly. + For ppc64 a call to a function in another translation unit might use a + different toc pointer thus disallowing direct branchess and making internal + ifuncs calls safe. */ +# undef libc_hidden_def +# define libc_hidden_def(name) \ + __hidden_ver1 (__time_vsyscall, __GI_time, __time_vsyscall); + +# endif /* !__powerpc64__ */ static time_t time_syscall (time_t *t) @@ -42,42 +66,19 @@ time_syscall (time_t *t) return result; } -void * -time_ifunc (void) -{ - PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565); - - /* If the vDSO is not available we fall back to the syscall. */ +# define INIT_ARCH() \ + PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565); \ void *vdso_time = _dl_vdso_vsym ("__kernel_time", &linux2615); - return (vdso_time ? VDSO_IFUNC_RET (vdso_time) - : (void*)time_syscall); -} -asm (".type time, %gnu_indirect_function"); -/* This is doing "libc_hidden_def (time)" but the compiler won't - * let us do it in C because it doesn't know we're defining time - * here in this file. */ -asm (".globl __GI_time"); - -/* __GI_time is defined as hidden and for ppc32 it enables the - compiler make a local call (symbol@local) for internal GLIBC usage. It - means the PLT won't be used and the ifunc resolver will be called directly. - For ppc64 a call to a function in another translation unit might use a - different toc pointer thus disallowing direct branchess and making internal - ifuncs calls safe. */ -#ifdef __powerpc64__ -asm ("__GI_time = time"); -#else -time_t -__time_vsyscall (time_t *t) -{ - return INLINE_VSYSCALL (time, 1, t); -} -asm ("__GI_time = __time_vsyscall"); -#endif +/* If the vDSO is not available we fall back to the syscall. */ +libc_ifunc_hidden (__redirect_time, time, + vdso_time + ? VDSO_IFUNC_RET (vdso_time) + : (void *) time_syscall); +libc_hidden_def (time) #else #include -#endif +#endif /* !SHARED */ -- cgit 1.4.1