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Refactor vDSO initialization code

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Linux vDSO initialization code the internal function pointers require a
lot of duplicated boilerplate over different architectures.  This patch
aims to simplify not only the code but the required definition to enable
a vDSO symbol.

The changes are:

  1. Consolidate all init-first.c on only one implementation and enable
     the symbol based on HAVE_*_VSYSCALL existence.

  2. Set the HAVE_*_VSYSCALL to the architecture expected names string.

  3. Add a new internal implementation, get_vdso_mangle_symbol, which
     returns a mangled function pointer.

Currently the clock_gettime, clock_getres, gettimeofday, getcpu, and time
are handled in an arch-independent way, powerpc still uses some
arch-specific vDSO symbol handled in a specific init-first implementation.

Checked on aarch64-linux-gnu, arm-linux-gnueabihf, i386-linux-gnu,
mips64-linux-gnu, powerpc64le-linux-gnu, s390x-linux-gnu,
sparc64-linux-gnu, and x86_64-linux-gnu.

	* sysdeps/powerpc/powerpc32/backtrace.c (is_sigtramp_address,
	is_sigtramp_address_rt): Use HAVE_SIGTRAMP_{RT}32 instead of SHARED.
	* sysdeps/powerpc/powerpc64/backtrace.c (is_sigtramp_address):
	Likewise.
	* sysdeps/unix/sysv/linux/aarch64/init-first.c: Remove file.
	* sysdeps/unix/sysv/linux/aarch64/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/arm/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/sparc/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Define value based on kernel exported
	name.
	* sysdeps/unix/sysv/linux/arm/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/i386/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETCPU_VSYSCALL, HAVE_TIME_VSYSCALL, HAVE_GET_TBFREQ,
	HAVE_SIGTRAMP_RT64, HAVE_SIGTRAMP_32, HAVE_SIGTRAMP_RT32i,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/riscv/sysdep.h (HAVE_CLOCK_GETRES_VSYSCALL,
	HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/sysdep.h (HAVE_CLOCK_GETRES_VSYSCALL,
	HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/dl-vdso.h (VDSO_NAME, VDSO_HASH): Define to
	invalid names if architecture does not define them.
	(get_vdso_mangle_symbol): New symbol.
	* sysdeps/unix/sysv/linux/init-first.c: New file.
	* sysdeps/unix/sysv/linux/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/init-first.c (gettimeofday,
	clock_gettime, clock_getres, getcpu, time): Remove declaration.
	(__libc_vdso_platform_setup_arch): Likewise and use
	get_vdso_mangle_symbol to setup vDSO symbols.
	(sigtramp_rt64, sigtramp32, sigtramp_rt32, get_tbfreq): Add
	attribute_hidden.
	* sysdeps/unix/sysv/linux/powerpc/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/sysdep-vdso.h (VDSO_SYMBOL): Remove
	definition.
This commit is contained in:
Adhemerval Zanella
2019-06-03 10:22:13 -03:00
parent b8386c2859
commit b8a7c7da4e
35 changed files with 236 additions and 649 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
sysdeps/unix/sysv/linux/powerpc/init-first.c
View File

@ -19,47 +19,18 @@
#include <dl-vdso.h>
#include <libc-vdso.h>
int (*VDSO_SYMBOL(gettimeofday)) (struct timeval *, void *)
attribute_hidden;
int (*VDSO_SYMBOL(clock_gettime)) (clockid_t, struct timespec *);
int (*VDSO_SYMBOL(clock_getres)) (clockid_t, struct timespec *);
unsigned long long (*VDSO_SYMBOL(get_tbfreq)) (void);
int (*VDSO_SYMBOL(getcpu)) (unsigned *, unsigned *);
time_t (*VDSO_SYMBOL(time)) (time_t *);
unsigned long long (*VDSO_SYMBOL(get_tbfreq)) (void) attribute_hidden;
#if defined(__PPC64__) || defined(__powerpc64__)
void *VDSO_SYMBOL(sigtramp_rt64);
void *VDSO_SYMBOL(sigtramp_rt64) attribute_hidden;
#else
void *VDSO_SYMBOL(sigtramp32);
void *VDSO_SYMBOL(sigtramp_rt32);
void *VDSO_SYMBOL(sigtramp32) attribute_hidden;
void *VDSO_SYMBOL(sigtramp_rt32) attribute_hidden;
#endif
static inline void
_libc_vdso_platform_setup (void)
__libc_vdso_platform_setup_arch (void)
{
void *p = get_vdso_symbol ("__kernel_gettimeofday");
PTR_MANGLE (p);
VDSO_SYMBOL (gettimeofday) = p;
p = get_vdso_symbol ("__kernel_clock_gettime");
PTR_MANGLE (p);
VDSO_SYMBOL (clock_gettime) = p;
p = get_vdso_symbol ("__kernel_clock_getres");
PTR_MANGLE (p);
VDSO_SYMBOL (clock_getres) = p;
p = get_vdso_symbol ("__kernel_get_tbfreq");
PTR_MANGLE (p);
VDSO_SYMBOL (get_tbfreq) = p;
p = get_vdso_symbol ("__kernel_getcpu");
PTR_MANGLE (p);
VDSO_SYMBOL (getcpu) = p;
p = get_vdso_symbol ("__kernel_time");
PTR_MANGLE (p);
VDSO_SYMBOL (time) = p;
VDSO_SYMBOL (get_tbfreq) = get_vdso_mangle_symbol (HAVE_GET_TBFREQ);
/* PPC64 uses only one signal trampoline symbol, while PPC32 will use
two depending if SA_SIGINFO is used (__kernel_sigtramp_rt32) or not
@ -67,13 +38,13 @@ _libc_vdso_platform_setup (void)
There is no need to pointer mangle these symbol because they will
used only for pointer comparison. */
#if defined(__PPC64__) || defined(__powerpc64__)
VDSO_SYMBOL(sigtramp_rt64) = get_vdso_symbol ("__kernel_sigtramp_rt64");
VDSO_SYMBOL(sigtramp_rt64) = get_vdso_symbol (HAVE_SIGTRAMP_RT64);
#else
VDSO_SYMBOL(sigtramp32) = get_vdso_symbol ("__kernel_sigtramp32");
VDSO_SYMBOL(sigtramp_rt32) = get_vdso_symbol ("__kernel_sigtramp_rt32");
VDSO_SYMBOL(sigtramp32) = get_vdso_symbol (HAVE_SIGTRAMP_32);
VDSO_SYMBOL(sigtramp_rt32) = get_vdso_symbol (HAVE_SIGTRAMP_RT32);
#endif
}
#define VDSO_SETUP _libc_vdso_platform_setup
#define VDSO_SETUP_ARCH __libc_vdso_platform_setup_arch
#include <csu/init-first.c>
#include <sysdeps/unix/sysv/linux/init-first.c>