mirror
/
go
mirror of https://github.com/golang/go.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

runtime: use clock_gettime to get ns resolution for time.now & runtime.nanotime 

For Linux/{386,arm}, FreeBSD/{386,amd64,arm}, NetBSD/{386,amd64}, OpenBSD/{386,amd64}.
Note: our Darwin implementation already has ns resolution.

Linux/386 (Core i7-2600 @ 3.40GHz, kernel 3.5.2-gentoo)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow          110          118   +7.27%

Linux/ARM (ARM Cortex-A8 @ 800MHz, kernel 2.6.32.28 android)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow          625          542  -13.28%

Linux/ARM (ARM Cortex-A9 @ 1GHz, Pandaboard)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow          992          909   -8.37%

FreeBSD 9-REL-p1/amd64 (Dell R610 Server with Xeon X5650 @ 2.67GHz)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow          699          695   -0.57%

FreeBSD 9-REL-p1/amd64 (Atom D525 @ 1.80GHz)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow         1553         1658   +6.76%

OpenBSD/amd64 (Dell E6410 with i5 CPU M 540 @ 2.53GHz)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow         1262         1236   -2.06%

OpenBSD/i386 (Asus eeePC 701 with Intel Celeron M 900MHz - locked to 631MHz)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow         5089         5043   -0.90%

NetBSD/i386 (VMware VM with Core i5 CPU @ 2.7GHz)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow          277          278   +0.36%

NetBSD/amd64 (VMware VM with Core i5 CPU @ 2.7Ghz)
benchmark       old ns/op    new ns/op    delta
BenchmarkNow          103          105   +1.94%

Thanks Maxim Khitrov, Joel Sing, and Dave Cheney for providing benchmark data.

R=jsing, dave, rsc
CC=golang-dev
https://golang.org/cl/6820120
This commit is contained in:
Shenghou Ma 2012-12-18 22:57:25 +08:00
parent 5b46fc417f
commit 7777bac6e4
10 changed files with 99 additions and 119 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
doc/go1.1.html
View File

@ -94,10 +94,10 @@ the <code>UnixConn</code>.
<h3 id="time">time</h3>
<p>
On Linux, previous versions of the time package returned times with
microsecond precision. The Go 1.1 implementation of time on Linux now returns times with
nanosecond precision. Code may exist that expects to be able to store
such a time in an external format with only microsecond precision,
On FreeBSD, Linux, NetBSD, OS X and OpenBSD, previous versions of the time package
returned times with microsecond precision. The Go 1.1 implementation of time on these
systems now returns times with nanosecond precision. Code may exist that expects to be
able to store such a time in an external format with only microsecond precision,
read it back, and recover exactly the same time instant.
In Go 1.1 the same time will not be recovered, since the external storage
will have discarded nanoseconds.

24
src/pkg/runtime/sys_freebsd_386.s
View File

@ -116,40 +116,38 @@ TEXT runtime·setitimer(SB), 7, $-4
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
MOVL $116, AX
MOVL $232, AX
LEAL 12(SP), BX
MOVL BX, 4(SP)
MOVL $0, 8(SP)
MOVL $0, 4(SP)
MOVL BX, 8(SP)
INT $0x80
MOVL 12(SP), AX // sec
MOVL 16(SP), BX // usec
MOVL 16(SP), BX // nsec
// sec is in AX, usec in BX
// sec is in AX, nsec in BX
MOVL AX, sec+0(FP)
MOVL $0, sec+4(FP)
IMULL $1000, BX
MOVL BX, nsec+8(FP)
RET
// int64 nanotime(void) so really
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB), 7, $32
MOVL $116, AX
MOVL $232, AX
LEAL 12(SP), BX
MOVL BX, 4(SP)
MOVL $0, 8(SP)
MOVL $0, 4(SP)
MOVL BX, 8(SP)
INT $0x80
MOVL 12(SP), AX // sec
MOVL 16(SP), BX // usec
MOVL 16(SP), BX // nsec
// sec is in AX, usec in BX
// sec is in AX, nsec in BX
// convert to DX:AX nsec
MOVL $1000000000, CX
MULL CX
IMULL $1000, BX
ADDL BX, AX
ADCL $0, DX
MOVL ret+0(FP), DI
MOVL AX, 0(DI)
MOVL DX, 4(DI)

22
src/pkg/runtime/sys_freebsd_amd64.s
View File

@ -94,31 +94,29 @@ TEXT runtime·setitimer(SB), 7, $-8
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
MOVL $116, AX
LEAQ 8(SP), DI
MOVQ $0, SI
MOVL $232, AX
MOVQ $0, DI
LEAQ 8(SP), SI
SYSCALL
MOVQ 8(SP), AX // sec
MOVL 16(SP), DX // usec
MOVQ 16(SP), DX // nsec
// sec is in AX, usec in DX
// sec is in AX, nsec in DX
MOVQ AX, sec+0(FP)
IMULQ $1000, DX
MOVL DX, nsec+8(FP)
RET
TEXT runtime·nanotime(SB), 7, $32
MOVL $116, AX
LEAQ 8(SP), DI
MOVQ $0, SI
MOVL $232, AX
MOVQ $0, DI
LEAQ 8(SP), SI
SYSCALL
MOVQ 8(SP), AX // sec
MOVL 16(SP), DX // usec
MOVQ 16(SP), DX // nsec
// sec is in AX, usec in DX
// sec is in AX, nsec in DX
// return nsec in AX
IMULQ $1000000000, AX
IMULQ $1000, DX
ADDQ DX, AX
RET

27
src/pkg/runtime/sys_freebsd_arm.s
View File

@ -86,39 +86,36 @@ TEXT runtime·setitimer(SB), 7, $-8
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
MOVW $8(R13), R0
MOVW $0, R1
SWI $116 // gettimeofday
MOVW $0, R0 // CLOCK_REALTIME
MOVW $8(R13), R1
SWI $232 // clock_gettime
MOVW 8(R13), R0 // sec.low
MOVW 16(R13), R2 // usec
MOVW 12(R13), R1 // sec.high
MOVW 16(R13), R2 // nsec
MOVW R0, 0(FP)
MOVW $0, R1
MOVW R1, 4(FP)
MOVW $1000, R3
MUL R3, R2
MOVW R2, 8(FP)
RET
// int64 nanotime(void) so really
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB), 7, $32
MOVW $8(R13), R0
MOVW $0, R1
SWI $116 // gettimeofday
MOVW $0, R0 // CLOCK_REALTIME
MOVW $8(R13), R1
SWI $232 // clock_gettime
MOVW 8(R13), R0 // sec.low
MOVW 16(R13), R2 // usec
MOVW 12(R13), R4 // sec.high
MOVW 16(R13), R2 // nsec
MOVW $1000000000, R3
MULLU R0, R3, (R1, R0)
MOVW $1000, R3
MOVW $0, R4
MUL R3, R2
MUL R3, R4
ADD.S R2, R0
ADC R4, R1
MOVW 0(FP), R3
MOVW R0, 0(R3)
MOVW R1, 4(R3)

24
src/pkg/runtime/sys_linux_386.s
View File

@ -104,40 +104,38 @@ TEXT runtime·mincore(SB),7,$0-24
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
MOVL $78, AX // syscall - gettimeofday
LEAL 8(SP), BX
MOVL $0, CX
MOVL $265, AX // syscall - clock_gettime
MOVL $0, BX
LEAL 8(SP), CX
MOVL $0, DX
CALL *runtime·_vdso(SB)
MOVL 8(SP), AX // sec
MOVL 12(SP), BX // usec
MOVL 12(SP), BX // nsec
// sec is in AX, usec in BX
// sec is in AX, nsec in BX
MOVL AX, sec+0(FP)
MOVL $0, sec+4(FP)
IMULL $1000, BX
MOVL BX, nsec+8(FP)
RET
// int64 nanotime(void) so really
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB), 7, $32
MOVL $78, AX // syscall - gettimeofday
LEAL 8(SP), BX
MOVL $0, CX
MOVL $265, AX // syscall - clock_gettime
MOVL $0, BX
LEAL 8(SP), CX
MOVL $0, DX
CALL *runtime·_vdso(SB)
MOVL 8(SP), AX // sec
MOVL 12(SP), BX // usec
MOVL 12(SP), BX // nsec
// sec is in AX, usec in BX
// sec is in AX, nsec in BX
// convert to DX:AX nsec
MOVL $1000000000, CX
MULL CX
IMULL $1000, BX
ADDL BX, AX
ADCL $0, DX
MOVL ret+0(FP), DI
MOVL AX, 0(DI)
MOVL DX, 4(DI)

23
src/pkg/runtime/sys_linux_arm.s
View File

@ -35,6 +35,7 @@
#define SYS_select (SYS_BASE + 142) // newselect
#define SYS_ugetrlimit (SYS_BASE + 191)
#define SYS_sched_getaffinity (SYS_BASE + 242)
#define SYS_clock_gettime (SYS_BASE + 263)
#define ARM_BASE (SYS_BASE + 0x0f0000)
#define SYS_ARM_cacheflush (ARM_BASE + 2)
@ -155,41 +156,37 @@ TEXT runtime·mincore(SB),7,$0
RET
TEXT time·now(SB), 7, $32
MOVW $8(R13), R0 // timeval
MOVW $0, R1 // zone
MOVW $SYS_gettimeofday, R7
MOVW $0, R0 // CLOCK_REALTIME
MOVW $8(R13), R1 // timespec
MOVW $SYS_clock_gettime, R7
SWI $0
MOVW 8(R13), R0 // sec
MOVW 12(R13), R2 // usec
MOVW 12(R13), R2 // nsec
MOVW R0, 0(FP)
MOVW $0, R1
MOVW R1, 4(FP)
MOVW $1000, R3
MUL R3, R2
MOVW R2, 8(FP)
RET
// int64 nanotime(void) so really
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB),7,$32
MOVW $8(R13), R0 // timeval
MOVW $0, R1 // zone
MOVW $SYS_gettimeofday, R7
MOVW $0, R0 // CLOCK_REALTIME
MOVW $8(R13), R1 // timespec
MOVW $SYS_clock_gettime, R7
SWI $0
MOVW 8(R13), R0 // sec
MOVW 12(R13), R2 // usec
MOVW 12(R13), R2 // nsec
MOVW $1000000000, R3
MULLU R0, R3, (R1, R0)
MOVW $1000, R3
MOVW $0, R4
MUL R3, R2
ADD.S R2, R0
ADC R4, R1
MOVW 0(FP), R3
MOVW R0, 0(R3)
MOVW R1, 4(R3)

18
src/pkg/runtime/sys_netbsd_386.s
View File

@ -98,9 +98,9 @@ TEXT runtime·setitimer(SB),7,$-4
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
LEAL 12(SP), BX
MOVL BX, 4(SP) // arg 1 - tp
MOVL $0, 8(SP) // arg 2 - tzp
MOVL $418, AX // sys_gettimeofday
MOVL $0, 4(SP) // arg 1 - clock_id
MOVL BX, 8(SP) // arg 2 - tp
MOVL $427, AX // sys_clock_gettime
INT $0x80
MOVL 12(SP), AX // sec - l32
@ -108,8 +108,7 @@ TEXT time·now(SB), 7, $32
MOVL 16(SP), AX // sec - h32
MOVL AX, sec+4(FP)
MOVL 20(SP), BX // usec - should not exceed 999999
IMULL $1000, BX
MOVL 20(SP), BX // nsec
MOVL BX, nsec+8(FP)
RET
@ -117,9 +116,9 @@ TEXT time·now(SB), 7, $32
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB),7,$32
LEAL 12(SP), BX
MOVL BX, 4(SP) // arg 1 - tp
MOVL $0, 8(SP) // arg 2 - tzp
MOVL $418, AX // sys_gettimeofday
MOVL $0, 4(SP) // arg 1 - clock_id
MOVL BX, 8(SP) // arg 2 - tp
MOVL $427, AX // sys_clock_gettime
INT $0x80
MOVL 16(SP), CX // sec - h32
@ -129,8 +128,7 @@ TEXT runtime·nanotime(SB),7,$32
MOVL $1000000000, BX
MULL BX // result in dx:ax
MOVL 20(SP), BX // usec
IMULL $1000, BX
MOVL 20(SP), BX // nsec
ADDL BX, AX
ADCL CX, DX // add high bits with carry

22
src/pkg/runtime/sys_netbsd_amd64.s
View File

@ -122,31 +122,29 @@ TEXT runtime·setitimer(SB),7,$-8
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
LEAQ 8(SP), DI // arg 1 - tp
MOVQ $0, SI // arg 2 - tzp
MOVL $418, AX // sys_gettimeofday
MOVQ $0, DI // arg 1 - clock_id
LEAQ 8(SP), SI // arg 2 - tp
MOVL $427, AX // sys_clock_gettime
SYSCALL
MOVQ 8(SP), AX // sec
MOVL 16(SP), DX // usec
MOVL 16(SP), DX // nsec
// sec is in AX, usec in DX
// sec is in AX, nsec in DX
MOVQ AX, sec+0(FP)
IMULQ $1000, DX
MOVL DX, nsec+8(FP)
RET
TEXT runtime·nanotime(SB),7,$32
LEAQ 8(SP), DI // arg 1 - tp
MOVQ $0, SI // arg 2 - tzp
MOVL $418, AX // sys_gettimeofday
MOVQ $0, DI // arg 1 - clock_id
LEAQ 8(SP), SI // arg 2 - tp
MOVL $427, AX // sys_clock_gettime
SYSCALL
MOVQ 8(SP), AX // sec
MOVL 16(SP), DX // usec
MOVL 16(SP), DX // nsec
// sec is in AX, usec in DX
// sec is in AX, nsec in DX
// return nsec in AX
IMULQ $1000000000, AX
IMULQ $1000, DX
ADDQ DX, AX
RET

24
src/pkg/runtime/sys_openbsd_386.s
View File

@ -98,40 +98,38 @@ TEXT runtime·setitimer(SB),7,$-4
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
MOVL $116, AX
MOVL $232, AX
LEAL 12(SP), BX
MOVL BX, 4(SP)
MOVL $0, 8(SP)
MOVL $0, 4(SP)
MOVL BX, 8(SP)
INT $0x80
MOVL 12(SP), AX // sec
MOVL 16(SP), BX // usec
MOVL 16(SP), BX // nsec
// sec is in AX, usec in BX
// sec is in AX, nsec in BX
MOVL AX, sec+0(FP)
MOVL $0, sec+4(FP)
IMULL $1000, BX
MOVL BX, nsec+8(FP)
RET
// int64 nanotime(void) so really
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB),7,$32
MOVL $116, AX
MOVL $232, AX
LEAL 12(SP), BX
MOVL BX, 4(SP)
MOVL $0, 8(SP)
MOVL $0, 4(SP)
MOVL BX, 8(SP)
INT $0x80
MOVL 12(SP), AX // sec
MOVL 16(SP), BX // usec
MOVL 16(SP), BX // nsec
// sec is in AX, usec in BX
// sec is in AX, nsec in BX
// convert to DX:AX nsec
MOVL $1000000000, CX
MULL CX
IMULL $1000, BX
ADDL BX, AX
ADCL $0, DX
MOVL ret+0(FP), DI
MOVL AX, 0(DI)
MOVL DX, 4(DI)

26
src/pkg/runtime/sys_openbsd_amd64.s
View File

@ -130,31 +130,29 @@ TEXT runtime·setitimer(SB),7,$-8
// func now() (sec int64, nsec int32)
TEXT time·now(SB), 7, $32
LEAQ 8(SP), DI // arg 1 - tp
MOVQ $0, SI // arg 2 - tzp
MOVL $116, AX // sys_gettimeofday
MOVQ $0, DI // arg 1 - clock_id
LEAQ 8(SP), SI // arg 2 - tp
MOVL $232, AX // sys_clock_gettime
SYSCALL
MOVQ 8(SP), AX // sec
MOVL 16(SP), DX // usec
MOVL 8(SP), AX // sec
MOVQ 16(SP), DX // nsec
// sec is in AX, usec in DX
// sec is in AX, nsec in DX
MOVQ AX, sec+0(FP)
IMULQ $1000, DX
MOVL DX, nsec+8(FP)
RET
TEXT runtime·nanotime(SB),7,$32
LEAQ 8(SP), DI // arg 1 - tp
MOVQ $0, SI // arg 2 - tzp
MOVL $116, AX // sys_gettimeofday
MOVQ $0, DI // arg 1 - clock_id
LEAQ 8(SP), SI // arg 2 - tp
MOVL $232, AX // sys_clock_gettime
SYSCALL
MOVQ 8(SP), AX // sec
MOVL 16(SP), DX // usec
MOVL 8(SP), AX // sec
MOVQ 16(SP), DX // nsec
// sec is in AX, usec in DX
// sec is in AX, nsec in DX
// return nsec in AX
IMULQ $1000000000, AX
IMULQ $1000, DX
ADDQ DX, AX
RET