[PATCH 07/18] linux: Remove supports_time64 () from clock_getres
Adhemerval Zanella
adhemerval.zanella@linaro.org
Thu Jun 17 11:50:53 GMT 2021
It breaks the usage case of live migration like CRIU or similar.
The performance drawback is it would require an extra syscall
on older kernels without 64-bit time support.
Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel
(with and without --enable-kernel=5.1) and on x86_64-linux-gnu.
---
sysdeps/unix/sysv/linux/clock_getres.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)
diff --git a/sysdeps/unix/sysv/linux/clock_getres.c b/sysdeps/unix/sysv/linux/clock_getres.c
index a9edec93e6..83f0593074 100644
--- a/sysdeps/unix/sysv/linux/clock_getres.c
+++ b/sysdeps/unix/sysv/linux/clock_getres.c
@@ -21,7 +21,6 @@
#include <time.h>
#include <sysdep-vdso.h>
-#include <time64-support.h>
#include <shlib-compat.h>
#include <kernel-features.h>
@@ -34,19 +33,14 @@ __clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
#ifndef __NR_clock_getres_time64
# define __NR_clock_getres_time64 __NR_clock_getres
#endif
- if (supports_time64 ())
- {
+
#ifdef HAVE_CLOCK_GETRES64_VSYSCALL
- r = INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
+ r = INLINE_VSYSCALL (clock_getres_time64, 2, clock_id, res);
#else
- r = INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
+ r = INLINE_SYSCALL_CALL (clock_getres_time64, clock_id, res);
#endif
-
- if (r == 0 || errno != ENOSYS)
- return r;
-
- mark_time64_unsupported ();
- }
+ if (r == 0 || errno != ENOSYS)
+ return r;
#ifndef __ASSUME_TIME64_SYSCALLS
/* Fallback code that uses 32-bit support. */
--
2.30.2
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