mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-29 10:08:53 +00:00
48 lines
1.1 KiB
C++
48 lines
1.1 KiB
C++
/*
|
|
* \brief Trace timestamp
|
|
* \author Josef Soentgen
|
|
* \date 2013-02-12
|
|
*
|
|
* Serialized reading of tsc on x86_64.
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2013-2017 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU Affero General Public License version 3.
|
|
*/
|
|
|
|
#ifndef _INCLUDE__SPEC__X86_64__TRACE__TIMESTAMP_H_
|
|
#define _INCLUDE__SPEC__X86_64__TRACE__TIMESTAMP_H_
|
|
|
|
#include <base/fixed_stdint.h>
|
|
|
|
namespace Genode { namespace Trace {
|
|
|
|
typedef uint64_t Timestamp;
|
|
|
|
inline Timestamp timestamp() __attribute((always_inline));
|
|
inline Timestamp timestamp()
|
|
{
|
|
uint32_t lo, hi;
|
|
__asm__ __volatile__ (
|
|
"xorl %%eax,%%eax\n\t" /* provide constant argument to cpuid to reduce variance */
|
|
"cpuid\n\t" /* synchronise, i.e. finish all preceeding instructions */
|
|
:
|
|
:
|
|
: "%rax", "%rbx", "%rcx", "%rdx"
|
|
);
|
|
__asm__ __volatile__ (
|
|
"rdtsc"
|
|
: "=a" (lo), "=d" (hi)
|
|
:
|
|
: "memory" /* prevent reordering of asm statements */
|
|
);
|
|
|
|
return (uint64_t)hi << 32 | lo;
|
|
}
|
|
} }
|
|
|
|
#endif /* _INCLUDE__SPEC__X86_64__TRACE__TIMESTAMP_H_ */
|