diff options
| author | Tuan Ta <qtt2@cornell.edu> | 2017-09-17 12:57:21 -0400 |
|---|---|---|
| committer | Tuan Ta <qtt2@cornell.edu> | 2018-01-10 01:02:53 +0000 |
| commit | 3fb4d59a9d66d729b292bf804a8b5fdbe6e40d89 (patch) | |
| tree | bba3357dcfe7cd0020b720b48c82743f3aa8de13 /src/sim/syscall_emul.hh | |
| parent | e8236503ce70ea83f4f61716f54421b32ce009ce (diff) | |
| download | gem5-3fb4d59a9d66d729b292bf804a8b5fdbe6e40d89.tar.xz | |
arch-riscv,sim: Support clone syscall in RISC-V
(1) This patch sets a correct order of clone syscall's arguments for
RISC-V. Linux kernel 4.15 uses CLONE_BACKWARDS flag by default for
RISC-V. The flag in the Linux kernel defines the list of clone syscall's
arguments in the following order:
clone_flags (flags)
newsp (newStack)
parent_tidptr (ptidPtr)
tls (tlsPtr)
child_tidptr (ctidPtr)
Code reference:
https://github.com/riscv/riscv-linux/blob/master/kernel/fork.c
https://github.com/riscv/riscv-linux/blob/master/arch/riscv/Kconfig
(2) This patch copies a parent thread's register values to its child
thread in clone syscall.
Change-Id: I2eb1c8e80990861080ce7153503ed784fb2c7bdf
Reviewed-on: https://gem5-review.googlesource.com/6904
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>
Diffstat (limited to 'src/sim/syscall_emul.hh')
| -rw-r--r-- | src/sim/syscall_emul.hh | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/src/sim/syscall_emul.hh b/src/sim/syscall_emul.hh index 2ffd6d6ae..ef61299a0 100644 --- a/src/sim/syscall_emul.hh +++ b/src/sim/syscall_emul.hh @@ -1241,11 +1241,23 @@ SyscallReturn cloneFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) { int index = 0; + TheISA::IntReg flags = p->getSyscallArg(tc, index); TheISA::IntReg newStack = p->getSyscallArg(tc, index); Addr ptidPtr = p->getSyscallArg(tc, index); + +#if THE_ISA == RISCV_ISA + /** + * Linux kernel 4.15 sets CLONE_BACKWARDS flag for RISC-V. + * The flag defines the list of clone() arguments in the following + * order: flags -> newStack -> ptidPtr -> tlsPtr -> ctidPtr + */ + Addr tlsPtr M5_VAR_USED = p->getSyscallArg(tc, index); + Addr ctidPtr = p->getSyscallArg(tc, index); +#else Addr ctidPtr = p->getSyscallArg(tc, index); Addr tlsPtr M5_VAR_USED = p->getSyscallArg(tc, index); +#endif if (((flags & OS::TGT_CLONE_SIGHAND)&& !(flags & OS::TGT_CLONE_VM)) || ((flags & OS::TGT_CLONE_THREAD) && !(flags & OS::TGT_CLONE_SIGHAND)) || @@ -1340,7 +1352,7 @@ cloneFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) ctc->setMiscReg(TheISA::MISCREG_ASI, TheISA::ASI_PRIMARY); for (int y = 8; y < 32; y++) ctc->setIntReg(y, tc->readIntReg(y)); -#elif THE_ISA == ARM_ISA or THE_ISA == X86_ISA +#elif THE_ISA == ARM_ISA or THE_ISA == X86_ISA or THE_ISA == RISCV_ISA TheISA::copyRegs(tc, ctc); #endif |