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[glibc] powerpc: Simplify vsyscall internal macros
- From: Adhemerval Zanella <azanella at sourceware dot org>
- To: glibc-cvs at sourceware dot org
- Date: 17 Sep 2019 20:15:45 -0000
- Subject: [glibc] powerpc: Simplify vsyscall internal macros
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=986a506481d4edb3b5c50c8245e915e39d248c7d
commit 986a506481d4edb3b5c50c8245e915e39d248c7d
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Mon Jun 3 21:07:25 2019 +0000
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.
Diff:
---
ChangeLog | 21 +++++++++++++++++++
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 +----------------
6 files changed, 59 insertions(+), 54 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 6f177f9..71cfb3f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,26 @@
2019-09-17 Adhemerval Zanella <adhemerval.zanella@linaro.org>
+ * 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/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):
diff --git a/sysdeps/unix/sysv/linux/libc-vdso.h b/sysdeps/unix/sysv/linux/libc-vdso.h
index 2e63aa1..792ac39 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 7593720..29b6624 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 <not-cancel.h>
#include <libc-vdso.h>
-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 5c1f8de..cb7da3b 100644
--- a/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h
+++ b/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h
@@ -22,17 +22,9 @@
#include <sysdep.h>
#include <sysdep-vdso.h>
-#include_next <libc-vdso.h>
-
-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 <dl-machine.h>
/* 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 <libc-vdso.h>
+
+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 1cbf159..a3bb552 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 fac7a9a..207d9d5 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); \