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| author | Carlos Eduardo Seo <cseo@linux.vnet.ibm.com> | 2018-08-23 20:16:19 -0300 |
|---|---|---|
| committer | Lynn Boger <laboger@linux.vnet.ibm.com> | 2018-08-31 13:12:31 +0000 |
| commit | dbd8af74723d2c98cbdcc70f7e2801f69b57ac5b (patch) | |
| tree | cbd54a861f3f00ca36761be6043ec60a2ec47adf /src/runtime/sys_linux_ppc64x.s | |
| parent | 8359b5e134052db0e5f1bc2257d496b0a81aa4fb (diff) | |
| download | go-dbd8af74723d2c98cbdcc70f7e2801f69b57ac5b.tar.gz go-dbd8af74723d2c98cbdcc70f7e2801f69b57ac5b.zip | |
runtime: add support for VDSO on ppc64x for use in walltime/nanotime
This change adds support for VDSO on ppc64x, making it possible to
avoid a syscall in walltime and nanotime.
BenchmarkClockVDSOAndFallbackPaths/vDSO-192 20000000 66.0 ns/op
BenchmarkClockVDSOAndFallbackPaths/Fallback-192 1000000 1456 ns/op
Change-Id: I3373bd804b6f122961de3ae9d034e6ccf35748e6
Reviewed-on: https://go-review.googlesource.com/131135
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Diffstat (limited to 'src/runtime/sys_linux_ppc64x.s')
| -rw-r--r-- | src/runtime/sys_linux_ppc64x.s | 94 |
1 files changed, 84 insertions, 10 deletions
diff --git a/src/runtime/sys_linux_ppc64x.s b/src/runtime/sys_linux_ppc64x.s index 483cb8ef9a..075adf2368 100644 --- a/src/runtime/sys_linux_ppc64x.s +++ b/src/runtime/sys_linux_ppc64x.s @@ -154,21 +154,87 @@ TEXT runtime·mincore(SB),NOSPLIT|NOFRAME,$0-28 // func walltime() (sec int64, nsec int32) TEXT runtime·walltime(SB),NOSPLIT,$16 - MOVD $0, R3 // CLOCK_REALTIME - MOVD $0(R1), R4 - SYSCALL $SYS_clock_gettime - MOVD 0(R1), R3 // sec - MOVD 8(R1), R5 // nsec + MOVD R1, R15 // R15 is unchanged by C code + MOVD g_m(g), R21 // R21 = m + + MOVD $0, R3 // CLOCK_REALTIME + + MOVD runtime·vdsoClockgettimeSym(SB), R12 // Check for VDSO availability + CMP R12, R0 + BEQ fallback + + // Set vdsoPC and vdsoSP for SIGPROF traceback. + MOVD LR, R14 + MOVD R14, m_vdsoPC(R21) + MOVD R15, m_vdsoSP(R21) + + MOVD m_curg(R21), R6 + CMP g, R6 + BNE noswitch + + MOVD m_g0(R21), R7 + MOVD (g_sched+gobuf_sp)(R7), R1 // Set SP to g0 stack + +noswitch: + SUB $16, R1 // Space for results + RLDICR $0, R1, $59, R1 // Align for C code + MOVD R12, CTR + MOVD R1, R4 + BL (CTR) // Call from VDSO + MOVD $0, R0 // Restore R0 + MOVD R0, m_vdsoSP(R21) // Clear vdsoSP + MOVD 0(R1), R3 // sec + MOVD 8(R1), R5 // nsec + MOVD R15, R1 // Restore SP + +finish: MOVD R3, sec+0(FP) MOVW R5, nsec+8(FP) RET + // Syscall fallback +fallback: + ADD $32, R1, R4 + SYSCALL $SYS_clock_gettime + MOVD 32(R1), R3 + MOVD 40(R1), R5 + JMP finish + TEXT runtime·nanotime(SB),NOSPLIT,$16 - MOVW $1, R3 // CLOCK_MONOTONIC - MOVD $0(R1), R4 - SYSCALL $SYS_clock_gettime - MOVD 0(R1), R3 // sec - MOVD 8(R1), R5 // nsec + MOVD $1, R3 // CLOCK_MONOTONIC + + MOVD R1, R15 // R15 is unchanged by C code + MOVD g_m(g), R21 // R21 = m + + MOVD runtime·vdsoClockgettimeSym(SB), R12 // Check for VDSO availability + CMP R12, R0 + BEQ fallback + + // Set vdsoPC and vdsoSP for SIGPROF traceback. + MOVD LR, R14 // R14 is unchanged by C code + MOVD R14, m_vdsoPC(R21) + MOVD R15, m_vdsoSP(R21) + + MOVD m_curg(R21), R6 + CMP g, R6 + BNE noswitch + + MOVD m_g0(R21), R7 + MOVD (g_sched+gobuf_sp)(R7), R1 // Set SP to g0 stack + +noswitch: + SUB $16, R1 // Space for results + RLDICR $0, R1, $59, R1 // Align for C code + MOVD R12, CTR + MOVD R1, R4 + BL (CTR) // Call from VDSO + MOVD $0, R0 // Restore R0 + MOVD $0, m_vdsoSP(R21) // Clear vdsoSP + MOVD 0(R1), R3 // sec + MOVD 8(R1), R5 // nsec + MOVD R15, R1 // Restore SP + +finish: // sec is in R3, nsec in R5 // return nsec in R3 MOVD $1000000000, R4 @@ -177,6 +243,14 @@ TEXT runtime·nanotime(SB),NOSPLIT,$16 MOVD R3, ret+0(FP) RET + // Syscall fallback +fallback: + ADD $32, R1, R4 + SYSCALL $SYS_clock_gettime + MOVD 32(R1), R3 + MOVD 48(R1), R5 + JMP finish + TEXT runtime·rtsigprocmask(SB),NOSPLIT|NOFRAME,$0-28 MOVW how+0(FP), R3 MOVD new+8(FP), R4 |