diff options
Diffstat (limited to 'src/runtime/asm_amd64.s')
| -rw-r--r-- | src/runtime/asm_amd64.s | 52 |
1 files changed, 19 insertions, 33 deletions
diff --git a/src/runtime/asm_amd64.s b/src/runtime/asm_amd64.s index 9a74a5310b..5840c32b5a 100644 --- a/src/runtime/asm_amd64.s +++ b/src/runtime/asm_amd64.s @@ -190,55 +190,41 @@ TEXT runtime·mcall(SB), NOSPLIT, $0-8 JMP AX RET -// switchtoM is a dummy routine that onM leaves at the bottom +// systemstack_switch is a dummy routine that systemstack leaves at the bottom // of the G stack. We need to distinguish the routine that // lives at the bottom of the G stack from the one that lives -// at the top of the M stack because the one at the top of -// the M stack terminates the stack walk (see topofstack()). -TEXT runtime·switchtoM(SB), NOSPLIT, $0-0 +// at the top of the system stack because the one at the top of +// the system stack terminates the stack walk (see topofstack()). +TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0 RET -// func onM_signalok(fn func()) -TEXT runtime·onM_signalok(SB), NOSPLIT, $0-8 +// func systemstack(fn func()) +TEXT runtime·systemstack(SB), NOSPLIT, $0-8 + MOVQ fn+0(FP), DI // DI = fn get_tls(CX) MOVQ g(CX), AX // AX = g MOVQ g_m(AX), BX // BX = m + MOVQ m_gsignal(BX), DX // DX = gsignal CMPQ AX, DX - JEQ ongsignal - JMP runtime·onM(SB) - -ongsignal: - MOVQ fn+0(FP), DI // DI = fn - MOVQ DI, DX - MOVQ 0(DI), DI - CALL DI - RET - -// func onM(fn func()) -TEXT runtime·onM(SB), NOSPLIT, $0-8 - MOVQ fn+0(FP), DI // DI = fn - get_tls(CX) - MOVQ g(CX), AX // AX = g - MOVQ g_m(AX), BX // BX = m + JEQ noswitch MOVQ m_g0(BX), DX // DX = g0 CMPQ AX, DX - JEQ onm + JEQ noswitch MOVQ m_curg(BX), BP CMPQ AX, BP - JEQ oncurg + JEQ switch - // Not g0, not curg. Must be gsignal, but that's not allowed. - // Hide call from linker nosplit analysis. - MOVQ $runtime·badonm(SB), AX + // Bad: g is not gsignal, not g0, not curg. What is it? + MOVQ $runtime·badsystemstack(SB), AX CALL AX -oncurg: +switch: // save our state in g->sched. Pretend to - // be switchtoM if the G stack is scanned. - MOVQ $runtime·switchtoM(SB), BP + // be systemstack_switch if the G stack is scanned. + MOVQ $runtime·systemstack_switch(SB), BP MOVQ BP, (g_sched+gobuf_pc)(AX) MOVQ SP, (g_sched+gobuf_sp)(AX) MOVQ AX, (g_sched+gobuf_g)(AX) @@ -246,7 +232,7 @@ oncurg: // switch to g0 MOVQ DX, g(CX) MOVQ (g_sched+gobuf_sp)(DX), BX - // make it look like mstart called onM on g0, to stop traceback + // make it look like mstart called systemstack on g0, to stop traceback SUBQ $8, BX MOVQ $runtime·mstart(SB), DX MOVQ DX, 0(BX) @@ -267,7 +253,7 @@ oncurg: MOVQ $0, (g_sched+gobuf_sp)(AX) RET -onm: +noswitch: // already on m stack, just call directly MOVQ DI, DX MOVQ 0(DI), DI @@ -727,7 +713,7 @@ needm: // the same SP back to m->sched.sp. That seems redundant, // but if an unrecovered panic happens, unwindm will // restore the g->sched.sp from the stack location - // and then onM will try to use it. If we don't set it here, + // and then systemstack will try to use it. If we don't set it here, // that restored SP will be uninitialized (typically 0) and // will not be usable. MOVQ m_g0(BP), SI |