diff options
Diffstat (limited to 'src/runtime/asm_riscv64.s')
| -rw-r--r-- | src/runtime/asm_riscv64.s | 32 |
1 files changed, 28 insertions, 4 deletions
diff --git a/src/runtime/asm_riscv64.s b/src/runtime/asm_riscv64.s index 759bae24b5..0a34a591fd 100644 --- a/src/runtime/asm_riscv64.s +++ b/src/runtime/asm_riscv64.s @@ -519,13 +519,23 @@ TEXT runtime·goexit(SB),NOSPLIT|NOFRAME|TOPFRAME,$0-0 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. + MOV fn+0(FP), X7 + BNE ZERO, X7, loadg + // Restore the g from frame. + MOV frame+8(FP), g + JMP dropm + +loadg: // Load m and g from thread-local storage. MOVBU runtime·iscgo(SB), X5 BEQ ZERO, X5, nocgo CALL 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 @@ -538,7 +548,7 @@ nocgo: needm: MOV g, savedm-8(SP) // g is zero, so is m. - MOV $runtime·needm(SB), X6 + MOV $runtime·needAndBindM(SB), X6 JALR RA, X6 // Set m->sched.sp = SP, so that if a panic happens @@ -609,10 +619,24 @@ havem: MOV savedsp-24(SP), X6 // must match frame size MOV X6, (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. MOV savedm-8(SP), X5 BNE ZERO, X5, droppedm + + // Skip dropm to reuse it in the next call, when a pthread key has been created. + MOV _cgo_pthread_key_created(SB), X5 + // It means cgo is disabled when _cgo_pthread_key_created is a nil pointer, need dropm. + BEQ ZERO, X5, dropm + MOV (X5), X5 + BNE ZERO, X5, droppedm + +dropm: MOV $runtime·dropm(SB), X6 JALR RA, X6 droppedm: |