github.com/MerlinKodo/gvisor@v0.0.0-20231110090155-957f62ecf90e/pkg/sentry/time/vdso_amd64.s (about)

     1  // Copyright 2021 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  #include "textflag.h"
    16  
    17  #define SYS_clock_gettime       228
    18  
    19  TEXT ·vdsoClockGettime(SB),NOSPLIT|NOFRAME,$0-24
    20  	MOVL clockid+0(FP), DI
    21  	MOVQ ts+8(FP), SI
    22  	MOVQ runtime·vdsoClockgettimeSym(SB), AX
    23  	CMPQ AX, $0
    24  	JEQ fallback
    25  	CALL AX
    26  	MOVQ AX, ret+16(FP)
    27  	RET
    28  fallback:
    29  	MOVQ $SYS_clock_gettime, AX
    30  	SYSCALL
    31  	MOVQ AX, ret+16(FP)
    32  	RET