diff options
Diffstat (limited to 'src/runtime/asm_arm64.s')
| -rw-r--r-- | src/runtime/asm_arm64.s | 32 |
1 files changed, 28 insertions, 4 deletions
diff --git a/src/runtime/asm_arm64.s b/src/runtime/asm_arm64.s index 6fe04a6445..5cce33d7fe 100644 --- a/src/runtime/asm_arm64.s +++ b/src/runtime/asm_arm64.s @@ -1015,10 +1015,20 @@ nosave: 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 + CBNZ R1, loadg + // Restore the g from frame. + MOVD frame+8(FP), g + B dropm + +loadg: // Load g from thread-local storage. BL runtime·load_g(SB) - // 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 @@ -1031,7 +1041,7 @@ TEXT ·cgocallback(SB),NOSPLIT,$24-24 needm: MOVD g, savedm-8(SP) // g is zero, so is m. - MOVD $runtime·needm(SB), R0 + MOVD $runtime·needAndBindM(SB), R0 BL (R0) // Set m->g0->sched.sp = SP, so that if a panic happens @@ -1112,10 +1122,24 @@ havem: MOVD savedsp-16(SP), R4 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 CBNZ R6, 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. + CBZ R6, dropm + MOVD (R6), R6 + CBNZ R6, droppedm + +dropm: MOVD $runtime·dropm(SB), R0 BL (R0) droppedm: |