diff options
| author | cui <cuiweixie@gmail.com> | 2020-08-12 17:33:41 +0000 |
|---|---|---|
| committer | Ian Lance Taylor <iant@golang.org> | 2020-08-19 00:02:38 +0000 |
| commit | 0941fc3f9ff43598d25fa6e964e7829a268102bf (patch) | |
| tree | 3404076ec3480dff5f705be5b24e7ed8fdde046b /src/runtime/sys_linux_amd64.s | |
| parent | 84a62453e5c01df3f7d0c48d9aca32832c2052c1 (diff) | |
| download | go-0941fc3f9ff43598d25fa6e964e7829a268102bf.tar.xz | |
runtime: reduce syscall when call runtime.clone
Change-Id: I3ea398fd86aae4c86557dd6fff65d90a6f756890
GitHub-Last-Rev: 4c295388f7b5e6768ffd2530337f78b4c75a9310
GitHub-Pull-Request: golang/go#40392
Reviewed-on: https://go-review.googlesource.com/c/go/+/244626
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Diffstat (limited to 'src/runtime/sys_linux_amd64.s')
| -rw-r--r-- | src/runtime/sys_linux_amd64.s | 34 |
1 files changed, 21 insertions, 13 deletions
diff --git a/src/runtime/sys_linux_amd64.s b/src/runtime/sys_linux_amd64.s index 621c01b365..8d90813589 100644 --- a/src/runtime/sys_linux_amd64.s +++ b/src/runtime/sys_linux_amd64.s @@ -592,13 +592,25 @@ TEXT runtime·clone(SB),NOSPLIT,$0 MOVQ stk+8(FP), SI MOVQ $0, DX MOVQ $0, R10 - + MOVQ $0, R8 // Copy mp, gp, fn off parent stack for use by child. // Careful: Linux system call clobbers CX and R11. - MOVQ mp+16(FP), R8 + MOVQ mp+16(FP), R13 MOVQ gp+24(FP), R9 MOVQ fn+32(FP), R12 - + CMPQ R13, $0 // m + JEQ nog1 + CMPQ R9, $0 // g + JEQ nog1 + LEAQ m_tls(R13), R8 +#ifdef GOOS_android + // Android stores the TLS offset in runtime·tls_g. + SUBQ runtime·tls_g(SB), R8 +#else + ADDQ $8, R8 // ELF wants to use -8(FS) +#endif + ORQ $0x00080000, DI //add flag CLONE_SETTLS(0x00080000) to call clone +nog1: MOVL $SYS_clone, AX SYSCALL @@ -612,27 +624,23 @@ TEXT runtime·clone(SB),NOSPLIT,$0 MOVQ SI, SP // If g or m are nil, skip Go-related setup. - CMPQ R8, $0 // m - JEQ nog + CMPQ R13, $0 // m + JEQ nog2 CMPQ R9, $0 // g - JEQ nog + JEQ nog2 // Initialize m->procid to Linux tid MOVL $SYS_gettid, AX SYSCALL - MOVQ AX, m_procid(R8) - - // Set FS to point at m->tls. - LEAQ m_tls(R8), DI - CALL runtime·settls(SB) + MOVQ AX, m_procid(R13) // In child, set up new stack get_tls(CX) - MOVQ R8, g_m(R9) + MOVQ R13, g_m(R9) MOVQ R9, g(CX) CALL runtime·stackcheck(SB) -nog: +nog2: // Call fn CALL R12 |