diff options
Diffstat (limited to 'src/runtime/asm_s390x.s')
| -rw-r--r-- | src/runtime/asm_s390x.s | 32 |
1 files changed, 28 insertions, 4 deletions
diff --git a/src/runtime/asm_s390x.s b/src/runtime/asm_s390x.s index d427c07de4..4c4a42e00a 100644 --- a/src/runtime/asm_s390x.s +++ b/src/runtime/asm_s390x.s @@ -564,13 +564,23 @@ g0: TEXT ·cgocallback(SB),NOSPLIT,$24-24 NO_LOCAL_POINTERS + // Skip cgocallbackg, just dropm when fn is nil, and frame is the saved g. + // It is used to dropm while thread is exiting. + MOVD fn+0(FP), R1 + CMPBNE R1, $0, loadg + // Restore the g from frame. + MOVD frame+8(FP), g + BR dropm + +loadg: // Load m and g from thread-local storage. MOVB runtime·iscgo(SB), R3 CMPBEQ R3, $0, nocgo BL runtime·load_g(SB) nocgo: - // If g is nil, Go did not create the current thread. + // If g is nil, Go did not create the current thread, + // or if this thread never called into Go on pthread platforms. // Call needm to obtain one for temporary use. // In this case, we're running on the thread stack, so there's // lots of space, but the linker doesn't know. Hide the call from @@ -583,7 +593,7 @@ nocgo: needm: MOVD g, savedm-8(SP) // g is zero, so is m. - MOVD $runtime·needm(SB), R3 + MOVD $runtime·needAndBindM(SB), R3 BL (R3) // Set m->sched.sp = SP, so that if a panic happens @@ -654,10 +664,24 @@ havem: MOVD savedsp-24(SP), R4 // must match frame size MOVD R4, (g_sched+gobuf_sp)(g) - // If the m on entry was nil, we called needm above to borrow an m - // for the duration of the call. Since the call is over, return it with dropm. + // If the m on entry was nil, we called needm above to borrow an m, + // 1. for the duration of the call on non-pthread platforms, + // 2. or the duration of the C thread alive on pthread platforms. + // If the m on entry wasn't nil, + // 1. the thread might be a Go thread, + // 2. or it's wasn't the first call from a C thread on pthread platforms, + // since the we skip dropm to resue the m in the first call. MOVD savedm-8(SP), R6 CMPBNE R6, $0, droppedm + + // Skip dropm to reuse it in the next call, when a pthread key has been created. + MOVD _cgo_pthread_key_created(SB), R6 + // It means cgo is disabled when _cgo_pthread_key_created is a nil pointer, need dropm. + CMPBEQ R6, $0, dropm + MOVD (R6), R6 + CMPBNE R6, $0, droppedm + +dropm: MOVD $runtime·dropm(SB), R3 BL (R3) droppedm: |