ipxe/src/arch/x86_64/include/bits/profile.h

#ifndef _BITS_PROFILE_H
#define _BITS_PROFILE_H

/** @file
 *
 * Profiling
 *
 */

FILE_LICENCE ( GPL2_OR_LATER );

#include <stdint.h>

/**
 * Get profiling timestamp
 *
 * @ret timestamp	Timestamp
 */
static inline __attribute__ (( always_inline )) uint64_t
profile_timestamp ( void ) {
	uint32_t eax;
	uint32_t edx;

	/* Read timestamp counter */
	__asm__ __volatile__ ( "rdtsc" : "=a" ( eax ), "=d" ( edx ) );
	return ( ( ( ( uint64_t ) edx ) << 32 ) | eax );
}

#endif /* _BITS_PROFILE_H */