[v2,4/8] powerpc: Simplify vsyscall internal macros
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Message ID 20190905205620.4646-4-adhemerval.zanella@linaro.org
State New
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Series
  • [v2,1/8] Remove PREPARE_VERSION and PREPARE_VERSION_KNOW
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Commit Message

Adhemerval Zanella Sept. 5, 2019, 8:56 p.m. UTC
Changes from previous version:

  - Fixed the issue with the removal of the CR0.SO check on
    INTERNAL_VSYSCALL_CALL.

--

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 ++++++
 .../sysv/linux/powerpc/get_timebase_freq.c    | 24 ++++++++++++-------
 .../unix/sysv/linux/powerpc/gettimeofday.c    |  2 +-
 sysdeps/unix/sysv/linux/powerpc/libc-vdso.h   | 24 ++++++++++---------
 .../sysv/linux/powerpc/powerpc32/sysdep.h     | 18 ++------------
 .../sysv/linux/powerpc/powerpc64/sysdep.h     | 19 +--------------
 sysdeps/unix/sysv/linux/powerpc/sysdep.h      |  1 +
 sysdeps/unix/sysv/linux/powerpc/time.c        |  2 +-
 8 files changed, 41 insertions(+), 56 deletions(-)

Comments

cseo Sept. 5, 2019, 10:05 p.m. UTC | #1
On 2019-09-05 17:56, Adhemerval Zanella wrote:
> diff --git a/sysdeps/unix/sysv/linux/libc-vdso.h
> b/sysdeps/unix/sysv/linux/libc-vdso.h
> index f681868137..199ae9a033 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
> +   architecture ABI.  It is used for powerpc64 elfv1 to create a ODP
> +   entry since kernvel vDSO does not provide it.  */

'required by the', 'ELFv1'

Typo - 'kernel'

The rest LGTM.
Adhemerval Zanella Sept. 17, 2019, 2:23 p.m. UTC | #2
Ack. I will commit this shortly if no one opposes, after I tested on the affected
architectures.

On 05/09/2019 19:05, cseo wrote:
> On 2019-09-05 17:56, Adhemerval Zanella wrote:
>> diff --git a/sysdeps/unix/sysv/linux/libc-vdso.h
>> b/sysdeps/unix/sysv/linux/libc-vdso.h
>> index f681868137..199ae9a033 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
>> +   architecture ABI.  It is used for powerpc64 elfv1 to create a ODP
>> +   entry since kernvel vDSO does not provide it.  */
> 
> 'required by the', 'ELFv1'
> 
> Typo - 'kernel'
> 
> The rest LGTM.

Patch
diff mbox series

diff --git a/sysdeps/unix/sysv/linux/libc-vdso.h b/sysdeps/unix/sysv/linux/libc-vdso.h
index f681868137..199ae9a033 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
+   architecture ABI.  It is used for powerpc64 elfv1 to create a ODP
+   entry since kernvel 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 *);
 #endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c b/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
index c245e97526..61ff6e2b2a 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/gettimeofday.c b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
index c59d5ddc10..e046594d40 100644
--- a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
@@ -58,7 +58,7 @@  __gettimeofday_syscall (struct timeval *tv, struct timezone *tz)
 }
 
 # define INIT_ARCH() \
-  void *vdso_gettimeofday = get_vdso_symbol ("__kernel_gettimeofday")
+  void *vdso_gettimeofday = get_vdso_symbol (HAVE_GETTIMEOFDAY_VSYSCALL)
   
 /* If the vDSO is not available we fall back syscall.  */
 libc_ifunc_hidden (__redirect___gettimeofday, __gettimeofday,
diff --git a/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h b/sysdeps/unix/sysv/linux/powerpc/libc-vdso.h
index 47e925493b..170adcc964 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 f459543fcd..703c668a92 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 06222f52e6..e7b2fce05f 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);					\
diff --git a/sysdeps/unix/sysv/linux/powerpc/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/sysdep.h
index 20167615c8..357d1b5243 100644
--- a/sysdeps/unix/sysv/linux/powerpc/sysdep.h
+++ b/sysdeps/unix/sysv/linux/powerpc/sysdep.h
@@ -24,6 +24,7 @@ 
 #define HAVE_CLOCK_GETTIME_VSYSCALL	"__kernel_clock_gettime"
 #define HAVE_GETCPU_VSYSCALL		"__kernel_getcpu"
 #define HAVE_TIME_VSYSCALL		"__kernel_time"
+#define HAVE_GETTIMEOFDAY_VSYSCALL	"__kernel_gettimeofday"
 #define HAVE_GET_TBFREQ                 "__kernel_get_tbfreq"
 
 #if defined(__PPC64__) || defined(__powerpc64__)
diff --git a/sysdeps/unix/sysv/linux/powerpc/time.c b/sysdeps/unix/sysv/linux/powerpc/time.c
index 38477bce8b..f0537a2307 100644
--- a/sysdeps/unix/sysv/linux/powerpc/time.c
+++ b/sysdeps/unix/sysv/linux/powerpc/time.c
@@ -67,7 +67,7 @@  time_syscall (time_t *t)
 }
 
 # define INIT_ARCH() \
-  void *vdso_time = get_vdso_symbol ("__kernel_time");
+  void *vdso_time = get_vdso_symbol (HAVE_TIME_VSYSCALL);
 
 /* If the vDSO is not available we fall back to the syscall.  */
 libc_ifunc_hidden (__redirect_time, time,