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[PATCH v2 01/16] linux: Fix vDSO macros build with time64 interfaces
- From: Adhemerval Zanella <adhemerval dot zanella at linaro dot org>
- To: libc-alpha at sourceware dot org
- Date: Tue, 17 Dec 2019 18:47:13 -0300
- Subject: [PATCH v2 01/16] linux: Fix vDSO macros build with time64 interfaces
Changes from previous version:
- Reinstate syscall fallback on INLINE_VSYSCALL, it simplifies
when the macro is used multiple times (as for clock_gettime
and clock_getres).
--
As indicated on libc-help [1] the ec138c67cb commit broke 32-bit
builds when configured with --enable-kernel=5.1 or higher. The
scenario 10 from [2] might also occur in this configuration and
INLINE_VSYSCALL will try to use the vDSO symbol and
HAVE_CLOCK_GETTIME64_VSYSCALL does not set HAVE_VSYSCALL prior its
usage.
Also, there is no easy way to just enable the code to use one
vDSO sysmbo since the macro INLINE_VSYSCALL is redefined if
HAVE_VSYSCALL is set.
Instead of adding more pre-processor handling and making the code
even more convoluted, this patch removes the requirement of defining
HAVE_VSYSCALL before including sysdep-vdso.h to enable vDSO usage.
The INLINE_VSYSCALL is now expected to be issued inside a
HAVE_*_VSYSCALL check, since it will try to use the internal vDSO
pointers.
Both clock_getres and clock_gettime vDSO code for time64_t were
removed since there is no vDSO setup code for the symbol (an
architecture can not set HAVE_CLOCK_GETTIME64_VSYSCALL).
Checked on i686-linux-gnu (default and with --enable-kernel=5.1),
x86_64-linux-gnu, aarch64-linux-gnu, and powerpc64le-linux-gnu.
I also checked against a build to mips64-linux-gnu and
sparc64-linux-gnu.
[1] https://sourceware.org/ml/libc-help/2019-12/msg00014.html
---
.../unix/sysv/linux/aarch64/gettimeofday.c | 4 --
sysdeps/unix/sysv/linux/clock_getres.c | 36 +++++++++++-------
sysdeps/unix/sysv/linux/clock_gettime.c | 38 +++++++++++--------
sysdeps/unix/sysv/linux/getcpu.c | 9 +----
.../unix/sysv/linux/powerpc/gettimeofday.c | 4 --
sysdeps/unix/sysv/linux/powerpc/time.c | 4 --
sysdeps/unix/sysv/linux/sched_getcpu.c | 15 +++-----
sysdeps/unix/sysv/linux/sysdep-vdso.h | 34 +----------------
sysdeps/unix/sysv/linux/x86/gettimeofday.c | 4 --
sysdeps/unix/sysv/linux/x86/time.c | 8 ++--
10 files changed, 58 insertions(+), 98 deletions(-)
diff --git a/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c b/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c
index 7e772e05ce..143c5c1507 100644
--- a/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/aarch64/gettimeofday.c
@@ -22,10 +22,6 @@
#include <time.h>
#include <sysdep.h>
-
-#ifdef HAVE_GETTIMEOFDAY_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
/* Used as a fallback in the ifunc resolver if VDSO is not available
diff --git a/sysdeps/unix/sysv/linux/clock_getres.c b/sysdeps/unix/sysv/linux/clock_getres.c
index 9497f78787..52671fa641 100644
--- a/sysdeps/unix/sysv/linux/clock_getres.c
+++ b/sysdeps/unix/sysv/linux/clock_getres.c
@@ -20,9 +20,6 @@
#include <errno.h>
#include <time.h>
-#ifdef HAVE_CLOCK_GETRES_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
#include <shlib-compat.h>
#include <kernel-features.h>
@@ -32,23 +29,34 @@ int
__clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
{
#ifdef __ASSUME_TIME64_SYSCALLS
-# ifndef __NR_clock_getres_time64
- return INLINE_VSYSCALL (clock_getres, 2, clock_id, res);
+ /* 64 bit ABIs or Newer 32-bit ABIs that only support 64-bit time_t. */
+# ifdef __NR_clock_getres_time64
+ return INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
# else
- return INLINE_SYSCALL (clock_getres_time64, 2, clock_id, res);
+# ifdef HAVE_CLOCK_GETRES_VSYSCALL
+ return INLINE_VSYSCALL (clock_getres, 2, clock_id, res);
+# else
+ return INLINE_SYSCALL_CALL (clock_getres, clock_id, res);
+# endif
# endif
#else
+ int r;
+ /* Old 32-bit ABI with possible 64-bit time_t support. */
# ifdef __NR_clock_getres_time64
- int ret = INLINE_SYSCALL (clock_getres_time64, 2, clock_id, res);
- if (ret == 0 || errno != ENOSYS)
- return ret;
+ r = INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
+ if (r == 0 || errno != ENOSYS)
+ return r;
# endif
+ /* Fallback code that uses 32-bit support. */
struct timespec ts32;
- int retval = INLINE_VSYSCALL (clock_getres, 2, clock_id, &ts32);
- if (! retval && res)
+# ifdef HAVE_CLOCK_GETRES_VSYSCALL
+ r = INLINE_VSYSCALL (clock_getres, 2, clock_id, &ts32);
+# else
+ r = INLINE_SYSCALL_CALL (clock_getres, clock_id, &ts32);
+# endif
+ if (r == 0)
*res = valid_timespec_to_timespec64 (ts32);
-
- return retval;
+ return r;
#endif
}
@@ -60,7 +68,7 @@ __clock_getres (clockid_t clock_id, struct timespec *res)
int retval;
retval = __clock_getres64 (clock_id, &ts64);
- if (! retval && res)
+ if (retval == 0 && res != NULL)
*res = valid_timespec64_to_timespec (ts64);
return retval;
diff --git a/sysdeps/unix/sysv/linux/clock_gettime.c b/sysdeps/unix/sysv/linux/clock_gettime.c
index 875c4fe905..e895812704 100644
--- a/sysdeps/unix/sysv/linux/clock_gettime.c
+++ b/sysdeps/unix/sysv/linux/clock_gettime.c
@@ -21,10 +21,6 @@
#include <errno.h>
#include <time.h>
#include "kernel-posix-cpu-timers.h"
-
-#ifdef HAVE_CLOCK_GETTIME_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
#include <shlib-compat.h>
@@ -34,22 +30,34 @@ int
__clock_gettime64 (clockid_t clock_id, struct __timespec64 *tp)
{
#ifdef __ASSUME_TIME64_SYSCALLS
-# ifndef __NR_clock_gettime64
-# define __NR_clock_gettime64 __NR_clock_gettime
-# define __vdso_clock_gettime64 __vdso_clock_gettime
+ /* 64 bit ABIs or Newer 32-bit ABIs that only support 64-bit time_t. */
+# ifdef __NR_clock_gettime64
+ return INLINE_SYSCALL_CALL (clock_gettime64, clock_id, tp);
+# else
+# ifdef HAVE_CLOCK_GETTIME_VSYSCALL
+ return INLINE_VSYSCALL (clock_gettime, 2, clock_id, tp);
+# else
+ return INLINE_SYSCALL_CALL (clock_gettime, clock_id, tp);
+# endif
# endif
- return INLINE_VSYSCALL (clock_gettime64, 2, clock_id, tp);
#else
-# if defined HAVE_CLOCK_GETTIME64_VSYSCALL
- int ret64 = INLINE_VSYSCALL (clock_gettime64, 2, clock_id, tp);
- if (ret64 == 0 || errno != ENOSYS)
- return ret64;
+ int r;
+ /* Old 32-bit ABI with possible 64-bit time_t support. */
+# ifdef __NR_clock_gettime64
+ r = INLINE_SYSCALL_CALL (clock_gettime64, clock_id, tp);
+ if (r == 0 || errno != ENOSYS)
+ return r;
# endif
+ /* Fallback code that uses 32-bit support. */
struct timespec tp32;
- int ret = INLINE_VSYSCALL (clock_gettime, 2, clock_id, &tp32);
- if (ret == 0)
+# ifdef HAVE_CLOCK_GETTIME_VSYSCALL
+ r = INLINE_VSYSCALL (clock_gettime, 2, clock_id, &tp32);
+# else
+ r = INLINE_SYSCALL_CALL (clock_gettime, clock_id, &tp32);
+# endif
+ if (r == 0)
*tp = valid_timespec_to_timespec64 (tp32);
- return ret;
+ return r;
#endif
}
diff --git a/sysdeps/unix/sysv/linux/getcpu.c b/sysdeps/unix/sysv/linux/getcpu.c
index fdd27203af..efb4bb7627 100644
--- a/sysdeps/unix/sysv/linux/getcpu.c
+++ b/sysdeps/unix/sysv/linux/getcpu.c
@@ -18,20 +18,15 @@
#include <errno.h>
#include <sched.h>
#include <sysdep.h>
-
-#ifdef HAVE_GETCPU_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
int
__getcpu (unsigned int *cpu, unsigned int *node)
{
-#ifdef __NR_getcpu
+#ifdef HAVE_GETCPU_VSYSCALL
return INLINE_VSYSCALL (getcpu, 3, cpu, node, NULL);
#else
- __set_errno (ENOSYS);
- return -1;
+ return INLINE_SYSCALL_CALL (getcpu, cpu, node, NULL);
#endif
}
weak_alias (__getcpu, getcpu)
diff --git a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
index 18d8f7cb7a..c40793fe64 100644
--- a/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c
@@ -17,10 +17,6 @@
#include <time.h>
#include <sysdep.h>
-
-#ifdef HAVE_GETTIMEOFDAY_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
static int
diff --git a/sysdeps/unix/sysv/linux/powerpc/time.c b/sysdeps/unix/sysv/linux/powerpc/time.c
index 80a4c73416..f2b4c76be8 100644
--- a/sysdeps/unix/sysv/linux/powerpc/time.c
+++ b/sysdeps/unix/sysv/linux/powerpc/time.c
@@ -18,10 +18,6 @@
#include <time.h>
#include <sysdep.h>
-
-#ifdef HAVE_TIME_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
static time_t
diff --git a/sysdeps/unix/sysv/linux/sched_getcpu.c b/sysdeps/unix/sysv/linux/sched_getcpu.c
index 65dd9fdda7..68ba7f3734 100644
--- a/sysdeps/unix/sysv/linux/sched_getcpu.c
+++ b/sysdeps/unix/sysv/linux/sched_getcpu.c
@@ -18,22 +18,17 @@
#include <errno.h>
#include <sched.h>
#include <sysdep.h>
-
-#ifdef HAVE_GETCPU_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
int
sched_getcpu (void)
{
-#ifdef __NR_getcpu
unsigned int cpu;
- int r = INLINE_VSYSCALL (getcpu, 3, &cpu, NULL, NULL);
-
- return r == -1 ? r : cpu;
+ int r = -1;
+#ifdef HAVE_GETCPU_VSYSCALL
+ r = INLINE_VSYSCALL (getcpu, 3, &cpu, NULL, NULL);
#else
- __set_errno (ENOSYS);
- return -1;
+ r = INLINE_SYSCALL_CALL (getcpu, &cpu, NULL, NULL);
#endif
+ return r == -1 ? r : cpu;
}
diff --git a/sysdeps/unix/sysv/linux/sysdep-vdso.h b/sysdeps/unix/sysv/linux/sysdep-vdso.h
index cf614fbf8b..76a211e39b 100644
--- a/sysdeps/unix/sysv/linux/sysdep-vdso.h
+++ b/sysdeps/unix/sysv/linux/sysdep-vdso.h
@@ -20,17 +20,14 @@
# define SYSDEP_VDSO_LINUX_H
#include <dl-vdso.h>
+#include <libc-vdso.h>
#ifndef INTERNAL_VSYSCALL_CALL
# define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...) \
funcptr (args)
#endif
-#ifdef HAVE_VSYSCALL
-
-# include <libc-vdso.h>
-
-# define INLINE_VSYSCALL(name, nr, args...) \
+#define INLINE_VSYSCALL(name, nr, args...) \
({ \
__label__ out; \
__label__ iserr; \
@@ -59,31 +56,4 @@
sc_ret; \
})
-# define INTERNAL_VSYSCALL(name, err, nr, args...) \
- ({ \
- __label__ out; \
- long v_ret; \
- \
- __typeof (__vdso_##name) vdsop = __vdso_##name; \
- PTR_DEMANGLE (vdsop); \
- if (vdsop != NULL) \
- { \
- v_ret = INTERNAL_VSYSCALL_CALL (vdsop, err, nr, ##args); \
- if (!INTERNAL_SYSCALL_ERROR_P (v_ret, err) \
- || INTERNAL_SYSCALL_ERRNO (v_ret, err) != ENOSYS) \
- goto out; \
- } \
- v_ret = INTERNAL_SYSCALL (name, err, nr, ##args); \
- out: \
- v_ret; \
- })
-#else
-
-# define INLINE_VSYSCALL(name, nr, args...) \
- INLINE_SYSCALL (name, nr, ##args)
-# define INTERNAL_VSYSCALL(name, err, nr, args...) \
- INTERNAL_SYSCALL (name, err, nr, ##args)
-
-#endif /* USE_VSYSCALL && defined HAVE_VSYSCALL */
-
#endif /* SYSDEP_VDSO_LINUX_H */
diff --git a/sysdeps/unix/sysv/linux/x86/gettimeofday.c b/sysdeps/unix/sysv/linux/x86/gettimeofday.c
index 190127d31e..8015c40210 100644
--- a/sysdeps/unix/sysv/linux/x86/gettimeofday.c
+++ b/sysdeps/unix/sysv/linux/x86/gettimeofday.c
@@ -18,10 +18,6 @@
#include <time.h>
#include <sysdep.h>
-
-#ifdef HAVE_GETTIMEOFDAY_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
static int
diff --git a/sysdeps/unix/sysv/linux/x86/time.c b/sysdeps/unix/sysv/linux/x86/time.c
index 4a03c46d21..85a9fc8a08 100644
--- a/sysdeps/unix/sysv/linux/x86/time.c
+++ b/sysdeps/unix/sysv/linux/x86/time.c
@@ -18,16 +18,16 @@
#include <time.h>
#include <sysdep.h>
-
-#ifdef HAVE_TIME_VSYSCALL
-# define HAVE_VSYSCALL
-#endif
#include <sysdep-vdso.h>
static time_t
time_vsyscall (time_t *t)
{
+#ifdef HAVE_TIME_VSYSCALL
return INLINE_VSYSCALL (time, 1, t);
+#else
+ return INLINE_SYSCALL_CALL (time, t);
+#endif
}
#ifdef SHARED
--
2.17.1